Model Engine Maker

Supporting => Engine Ancillaries => Topic started by: Jo on October 16, 2012, 07:47:20 AM

Title: governors
Post by: Jo on October 16, 2012, 07:47:20 AM
One of those parts of a model engine that used to cause me consternation was the governor :ShakeHead:. The second engine I nearly completed (the first was a Stuart 10V which was completed) was my Mary, I say nearly because whilst I finished the engine and got it running, oh dear nearly 20 years ago, the part that eluded me was the governor :disappointed::

(http://i214.photobucket.com/albums/cc12/jothoms/Mary/Untitled.jpg)

The governor on the Mary is a simple Watt governor, a design that is found on so many engines, including steam and Gas engines:

(http://i214.photobucket.com/albums/cc12/jothoms/Mary/IMG_1307.jpg)

I suppose the parts that I found so fearful were those spindly links with minute forked ends, the top hat and the lower sliding sleeve:

(http://i214.photobucket.com/albums/cc12/jothoms/Mary/IMG_1304.jpg)

The links, whilst fiddle, can be easily overcome with a slitting saw and then either side milled. I have found it easier to break the top hat and lower sleeve down into easy to make components and silver solder them.

Another challenge with governors are those pivots that hold the arms together. I have gone away from using nuts and bolts to using a male and female pin through the pivot points, which you can see an example of these in this picture:

(http://i214.photobucket.com/albums/cc12/jothoms/Mary/IMG_1306.jpg)

The final scary part is those thin links with big ends. Again a bit of thinking and they to become easy, from cutting the end from a piece of plate:

(http://i214.photobucket.com/albums/cc12/jothoms/Mary/IMG_1301.jpg)

Silver soldering it to a long thin shaft:

(http://i214.photobucket.com/albums/cc12/jothoms/Mary/IMG_1302.jpg)
(http://i214.photobucket.com/albums/cc12/jothoms/Mary/IMG_1303.jpg)

And then filing to shape:

(http://i214.photobucket.com/albums/cc12/jothoms/Mary/IMG_1305.jpg)

Of course then there is those bevel gears :hellno: ... but thankfully they are relatively cheap to buy, so if you don't want to cut them you don't have to.

--------

But to really explain how to make a governor I really should go back to the beginning. So please stay with me I first have to draw up the one for my Stothert and Pitt(s) and then over the comming week(s) I will make them  ;).

Jo
Title: Re: governors
Post by: Pete49 on October 16, 2012, 11:22:46 AM
Chairs set up the chips & fizzy drink getting cold ...ready when you are  :Lol:
Pete
Title: Re: governors
Post by: zeeprogrammer on October 16, 2012, 11:34:00 AM
I'm watching too.
Thanks for taking the time Jo.

I noticed the 'male and female pins'. I can't tell in the picture...are they threaded? I'm using several of those (threaded) on my current project and am glad to have a name for them.

What material was used to make the thin link you silver soldered?
Title: Re: governors
Post by: Jo on October 16, 2012, 11:48:07 AM
I noticed the 'male and female pins'. I can't tell in the picture...are they threaded?

What material was used to make the thin link you silver soldered?

No they are not threaded, the good ones are a press fit, the bad ones are kept together with superglue or something stronger ;) .

The links are just boring old mild steel. I keep thinking of moving over to 303 stainless but that can be tricky to get the silver solder to stick and it has a habit of bending :ShakeHead:

Jo
Title: Re: governors
Post by: steamer on October 16, 2012, 12:03:18 PM
Oh well and truly strapped in for this ride.....note book out....lots of sharp pencils......... :cheers:
Title: Re: governors
Post by: mzt on October 16, 2012, 12:20:23 PM
I've already written down the first note, about those press fitted pins.

Marcello
Title: Re: governors
Post by: gbritnell on October 16, 2012, 12:27:36 PM
Hi Jo,
Here's a shot of my Mary governor if it helps.
gbritnell
Title: Re: governors
Post by: smfr on October 16, 2012, 04:59:58 PM
Pulling up a chair!

Jo, you mentioned using 303 stainless, but I seem to recall reading somewhere that it was to be avoided on "authentic" scale models because the color is wrong. Material snobbishness, or genuine concern?

Simon
Title: Re: governors
Post by: Jo on October 16, 2012, 05:12:43 PM
Sorry Simon  :old: my eye sight is not good enough to notice the difference, especially in these small sizes. I suspect that the commercially brought small nuts and bolts are not high tensile either.

Jo
Title: Re: governors
Post by: Don1966 on October 16, 2012, 05:26:18 PM
I am diffinally in on this thread. Pulling up my chair as well.  :DrinkPint: I will be watching the commericals till the next reply. This should be very interesting and educational as well.

Don
Title: Re: governors
Post by: Jo on October 16, 2012, 07:28:04 PM
Here is an example of a lost wax governor, that came as part of a casting set:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/lostwaxcasting.jpg)

It is a very nice casting, whilst it will twirl it won't go "balls out" :ShakeHead:.

This is the governor I have chosen to build for this thread:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/crosssection.jpg)

Ok this is a very simple drawing, so lets look at the governor in detail:

From the bottom, it is mounted on the engine plinth using this simple casting:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/base.jpg)

There is a pair of 16 tooth bevel gears ( I must calculate the DP of these). Then we come to the governor sleeve:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_0101.jpg)

On most engines it is this sleeve that has a collar onto which the linkage that goes off to the throttle valve mounts but this engine was originally built for an exhibition so they didn't bother adding the collar. Either side you will see a pair of links, we will be doing these "en-block" 8).

Now to the arms, as normal the balls attach with a little collar, the lower half of the drop links are barrelled with the mount of the links in the middle and the top has a very nice u section.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_0104.jpg)

These arms end on the governor fixed sleeve that has a pretty curve to it:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_0114.jpg)

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/09190015.jpg)

The governor shaft ends in a bush mounted in an arm that goes across the entablature and ends on a pretty nut (that you will have to wait for the drawings to see ;))

I have started the drawings.....it will keep me busy for a couple of lunchtimes ;D.

Jo
Title: Re: governors
Post by: jonesie on October 16, 2012, 11:27:12 PM
thanks jo i will be watching also just what i need one more thing to build. jonesie
Title: Re: governors
Post by: Captain Jerry on October 16, 2012, 11:27:32 PM
Jo

This could not have come at a better time.  My "Notacorliss" is going to need one soon so in anticipation, I knocked off a pedestal for the mounting.  Six flutes on a tapered column. 

(http://i468.photobucket.com/albums/rr41/CaptainJerry_Albumlbum/Corliss/ItRUNS002.jpg)

(http://i468.photobucket.com/albums/rr41/CaptainJerry_Albumlbum/Corliss/ItRUNS001.jpg)

I'm sure to learn some useful stuff here,

Jerry
Title: Re: governors
Post by: steamer on October 17, 2012, 12:01:59 AM
Man this is an awesome thread!.....

Dave
Title: Re: governors
Post by: Jo on October 17, 2012, 10:07:42 PM
Jerry, I fear you are much faster than me at this (or do you get more time?)

I am half way through the drawings 8). The bevels are keeping me awake, the large pair are 16 teeth, 16.5mm O/D... that is about module 1 (and all my cutters are DP :Doh:,), the smaller pair are 8mm o/d, that is 48DP. My smallest gear cutters are 32DP but the observant amongst you will have noticed that I already have the bevels for the smaller governor. :whoohoo: so only one pair to cut and that will be in phosphor bronze or brass. Must do the calculations for those bigger gears....

Jo
Title: Re: governors
Post by: Dan Rowe on October 17, 2012, 11:50:44 PM
Jo,
If you use the 32 DP cutters you could add 2 teeth to make 18 teeth then the OD is 5/8".

 :DrinkPint:
Dan
Title: Re: governors
Post by: Captain Jerry on October 18, 2012, 01:29:53 AM
Jerry, I fear you are much faster than me at this (or do you get more time?)

Jo

Jo, I am retired so I may get more time.  I am also older and getting older fast so I have to work fast while I am still able to.  I am also not ashamed of working quick and dirty if I can get away with it.  The pedestal is literally only a fifteen minute job.  If you start with aluminum hex bar, you don't even have to set up a dividing head or spindexer for the flutes.  You can then index the blank in the mill vise.  I made a second one a bit faster because I decided I wanted to flare the top.

(http://i468.photobucket.com/albums/rr41/CaptainJerry_Albumlbum/Corliss/ItRUNS004.jpg)

I appreciate the attention to detail that you bring to your projects.  That is something that I really need to work on.

Jerry



Title: Re: governors
Post by: jonesie on October 18, 2012, 03:07:22 PM
 i like the gear driven gov.just received my copy of gears and gear cutting by ivan law, and with a quick look thru this looks like a real good buy.will be watching .  jonesie
Title: Re: governors
Post by: Jo on October 19, 2012, 08:41:37 AM
I have produced a rough set of drawings :D:

(http://i214.photobucket.com/albums/cc12/jothoms/Stothert%20and%20Pitt/StothertGovernordrawing1V0a.jpg)

(http://i214.photobucket.com/albums/cc12/jothoms/Stothert%20and%20Pitt/StothertGovernordrawing2V0a.jpg)

The plan is to knock this up in between continuing work on my Double Tandem Compound over the next week.

Jo
Title: Re: governors
Post by: Jo on October 19, 2012, 03:45:43 PM
I always start a governor with the spindle. It is one of the simplest parts and everything else hangs off it. At the bottom of the spindle this engine has a nice bronze bearing that I have chosen to make out of this recycled gunmetal sprue. (The smaller one is made from a 1/2" brass noggin from the come in handy box).

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1913.jpg)

The machining of the base for the larger one was conducted on the Prazimat using initially a 3 jaw SC chuck to machine the top and the bore.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1914.jpg)

And then mounted in a 5C collet for the underside to be machined.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1916.jpg)

This still needs the three mounting holes drilled but it was getting cooler and hasn't stopped raining all day so I wimped indoors. Before we go we need to scale the drawing for the second engine:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1917.jpg)

As you can see not everything has been halved, the scale size just would not have the strength needed.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1918.jpg)
It took a little longer to making this base mounting than the first due to the power of the Cowells. Then came those all important acorns at the top of the spindle:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1921.jpg)

So I now have two spindles, with base:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1923.jpg)

And the acorn sticks through to the middle of the entablature, where in good time there will be the top bearing mounted in a strut:
(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1926.jpg)

The next job is the sleeves, these are one of those interesting bits I enjoy :LittleDevil:.

Jo
Title: Re: governors
Post by: NickG on October 19, 2012, 04:20:31 PM
Hi Jo, are these the Cotswold Heritage castings or is yours a larger scale than that?

Interesting thread this one, thanks.

Nick

Title: Re: governors
Post by: Jo on October 19, 2012, 04:35:02 PM
The smaller engine is based around a set of Cotswold Heritage castings. But I will only be using the bevel gears from the set for the smaller governor. Both are being built around my measurements of our (University of Bath's) original engine :Love:.

The build thread for these engines is here: http://www.modelenginemaker.com/index.php/topic,809.0.html

Jo
Title: Re: governors
Post by: Don1966 on October 19, 2012, 07:43:31 PM
Jo, I am thoroughly enjoying this thread and learning as you progress. All of this is new to me as I am an electrician/technician by trade, so I am game to all you are presenting here. Thanks for taking the time to show us less skilled machinist.

Don
Title: Re: governors
Post by: NickG on October 19, 2012, 08:02:03 PM
Thanks Jo, the quality of those castings looks pretty good. I was shocked when I realised the original size ..

Wonderful job on the large scale so far, can't wait until it's picked back up!
Title: Re: governors
Post by: Jo on October 20, 2012, 04:52:58 PM
Today we are making the fixed sleeves for both the 1/6th and 1/12th scale engines. The starting point it to create a constructional drawing, showing the parts from which they are going to be made. On the drawing the black are the measurements for the 1/6th scale engine :D, the red are for the 1/12th scale ;D, you will note that not all the measurements are halved:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1935.jpg)

Starting with the body, turn to profile:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1927.jpg)

Bore to suit the spindle diameter:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1928.jpg)

Now we slit the end to take the arm hanger. You can use a slot drill if you want but I prefer a slitting saw and to take multiple cuts:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1929.jpg)

Which gives us this:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1930.jpg)

That?s it for the body, now for the arm hanger. This took a while as I first had to hack some suitable material out of an off cut. Once to overall size these have been coordinate drilled. Note the holes in the top these are smaller than the spindle diameter (the arms are the width of the spindle diameter so this assembly hole must be smaller).

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1931.jpg)

We now need to profile the arms, yes you can use a mill and a rotary table but these were hand filed using my collection of various buttons superglued to the blocks as shown:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1933.jpg)

Next we check the fit of the arms in the slots:
(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1934.jpg)

Now we need to make our assembly piece it is simply a brass sleeve part the diameter to suite the spindle diameter, part the reduced size in the arms:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1939.jpg)

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1936.jpg)
Now we use the assembly tubes  to keep the two parts aligned whilst we silver solder them together.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1938.jpg)

You want as little silver solder as possible and flux only where you want silver solder. This is what they looked like after:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1940.jpg)

Remember if you put too much silver solder on you will only have to remove it later. These are now cleaned up whilst they are still on the parent metal. It gives you something to hold in the vice. Now its is off to the lathe, drill and ream for the spindle diameter.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1945.jpg)

You should find that the assembly piece will come out with the drill meaning there is little to ream. Once the bore is to size each can be parted off, leaving us with two sleeves.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1948.jpg)

The second sleeve tomorrow. (I should be working on the DTC :ShakeHead:).

I have been thinking about balls and sadly I have not got the right sized ones so cannot cheat for the larger engine, so it looks like I will have to make them.

Jo
Title: Re: governors
Post by: zeeprogrammer on October 20, 2012, 05:20:48 PM
Very nice and highly interesting.

I was glad to see your box of buttons. I haven't seen many buttons, and I'm just starting my collection, so it helped to see what others have.

How did you do the cleaning up of the silver solder. Just filing? A bit of turning? Will you be pickling it?

Title: Re: governors
Post by: Jo on October 20, 2012, 05:26:18 PM
I knock up buttons as and when I need them with the smaller diameter designed to fit half way through the target metal to be reduced. They are left unhardened and then thrown when they get too damaged.

They were pickled in sulphuric acid but that only takes off the flux residue. The cleaning up was done with needle files.

Jo
Title: Re: governors
Post by: smfr on October 20, 2012, 07:09:43 PM
 :pinkelephant: Very excited to see some build progress here. This small stuff is so neat to see being made.

Simon
Title: Re: governors
Post by: Jo on October 21, 2012, 04:20:47 PM
The sliding sleeve is very much like the fixed sleeve except that we need an additional collar to fit under the arm section:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1952.jpg)

This is the set of parts made:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1954.jpg)

You will notice I chose to part the larger one from the parent metal. I did this thinking I was going to mount it in the dividing head but as it was I mounted it in the vice to do the slitting. These are the parts silver soldered together:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1956.jpg)

I then used some soft solder to help hide some of the gaps. Having cleaned them up here is our second sleeves:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1957.jpg)

They might need a bit more cleaning up :disappointed:

Jo
Title: Re: governors
Post by: Don1966 on October 21, 2012, 04:34:43 PM
Awesome Jo, I like the way all the small parts end up fitting together. This gives me more insite on how to go about things. I never really realized that making parts had so many options. This is a great thread keep up to great work.

Don
Title: Re: governors
Post by: Jo on October 22, 2012, 03:33:23 PM
The task for today is to machine the weights ;). I have two spherical  turning attachments, today I am looking to use my up and over one. To use this I need to first machine the following profile:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1972.jpg)

It is worth keeping the diameter of the rod for the weight slightly over sized at this point because these spherical turning attachments need to be set up otherwise it results in odd shaped turnings :mischief:. So here is the blank for machining:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1959.jpg)

So I have now set up ( :noidea:) the spherical turning tool and start by making a first cut to confirm that it is central:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1960.jpg)

As it shapes up if the tool is incorrectly set you will find that the outcome is a weight that is either squat or oval :naughty:. So this is what we end up with:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1968.jpg)

It is a good point now to get your emery out and give it a polish. We now machine the collar at the top of the weight.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1970.jpg)

Use a small safety file to merge any turning lines around the collar and then part off.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1971.jpg)

The smaller weights were also done the same way: So at the end of the day four weights :LittleDevil:. There is little point in polishing them further as they are due to be painted.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1974.jpg)

Jo
Title: Re: governors
Post by: smfr on October 22, 2012, 04:37:46 PM
Nice, Jo! Could you give us a shot of the "up and over" ball-turning tool?

Simon
Title: Re: governors
Post by: steamer on October 22, 2012, 04:50:44 PM
Nice, Jo! Could you give us a shot of the "up and over" ball-turning tool?

Simon

Simon beat me to it! :ThumbsUp:
Dave
Title: Re: governors
Post by: Jo on October 23, 2012, 11:47:29 AM
This is my spherical turning tool I used for this job:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1986.jpg)
(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1984.jpg)

I built it using the Hemming way drawings. It is fairly simple just a tapered boss running in a head that is on a rotating mount.  The only important measurement is that the tool holder holds the piece of tool steel at 7 degrees.  Looking at the drawings I also need to make the internal tool holder.

Jo
Title: Re: governors
Post by: Bogstandard on October 23, 2012, 01:18:52 PM
Just as an aside, if you don't have a ball turning tool, and even though I have an up and over one that uses my boring head off the mill for the end part, I find it easier to just hot up a couple of the correct sized ball bearings to soften them, then drill and tap to the size I want.

One of the main problems with me though is that I have a ball bearing fetish, and use them whenever I can, having almost every size from real tiny ones up to 1" diameter.


John
Title: Re: governors
Post by: Jo on October 23, 2012, 04:16:33 PM
I find it easier to just hot up a couple of the correct sized ball bearings to soften them, then drill and tap to the size I want.

That had been my original plan but I did not have any 16mm balls, hence being forced to turn them.

---------------------
Today I started on the drop links, this is the design:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1979.jpg)

These are both going to be machined out of square, so the starting point was to  mount the four jaw SC chuck and face the ends. Over to the mill and the pivot holes were coordinate drilled. That gave us these two bars as starting points:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1987.jpg)

You can see that I have marked up the material with permanent markers, I have also coated the end of the stock that these came off with the same marker pen. It gives a slight protection from the rust bug.

Off to the mill, I chose to do the smaller one first, so first job square everything up. As there will only be 0.5mm on either side of the slot on the smaller arm I chose to check the set up with a bit of scrap 3.2mm before starting on the main arm:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1989.jpg)

There is no rush, I took 16 cuts to cut these slots using a 2mm slot drill running at 3000rpm, if you rush all that happens is you break a very expensive slot drill.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1991.jpg)

So I have slotted for the first arm :whoohoo:, I will do the other tomorrow.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1992.jpg)

Jo

Title: Re: governors
Post by: smfr on October 23, 2012, 04:48:51 PM
Good progress, Jo. I like the toolpost-mounted ball turner. I have a carriage-mounted one and it doesn't get close enough to the chuck for most things.

Simon
Title: Re: governors
Post by: sco on October 23, 2012, 09:37:07 PM
This is my spherical turning tool I used for this job:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1986.jpg)
(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1984.jpg)

I built it using the Hemming way drawings. It is fairly simple just a tapered boss running in a head that is on a rotating mount.  The only important measurement is that the tool holder holds the piece of tool steel at 7 degrees.  Looking at the drawings I also need to make the internal tool holder.

Jo

Snap!  Here's mine in action;

https://www.youtube.com/watch?v=UVc0ZbVQVoE
Title: Re: governors
Post by: Jo on October 23, 2012, 10:09:12 PM
Thanks Simon, A video explains how these spherical turning tools work so much easier than trying to describe it in words :ThumbsUp:

Jo
Title: Re: governors
Post by: NickG on October 24, 2012, 05:19:14 AM
are there any advantages of doing it that way?
Title: Re: governors
Post by: Jo on October 24, 2012, 07:17:57 AM
Other means of making spheres include form tools, which I use for making the smaller ones the 8mm was the limit to what I would look to use this tool for. Softening ball bearings to use can be hit and miss, I find I have to try to soften 4 to hope to get two that my drills can touch.

You can also get spherical turners that mount on the cross slide and go around the work rather than over. To use these you have to take the top slide off. But where the up and over tool only needs about an 1 1/2" clearance to the chuck, these need a lot more.

Jo
Title: Re: governors
Post by: AussieJimG on October 24, 2012, 07:45:43 AM
This is a great thread  Jo, I am enjoying it immensely and learning heaps. Thank you for posting the detail and the sage advice.

Jim
Title: Re: governors
Post by: Jasonb on October 24, 2012, 07:58:26 AM
Jo if you are buying the balls then get stainless steel ones they are not as hard as steel so you can drill them with care and no need to polish them back up afterwards.

J
Title: Re: governors
Post by: sco on October 24, 2012, 09:04:10 AM
Other means of making spheres include form tools, which I use for making the smaller ones the 8mm was the limit to what I would look to use this tool for. Softening ball bearings to use can be hit and miss, I find I have to try to soften 4 to hope to get two that my drills can touch.

You can also get spherical turners that mount on the cross slide and go around the work rather than over. To use these you have to take the top slide off. But where the up and over tool only needs about an 1 1/2" clearance to the chuck, these need a lot more.

Jo

For really small stuff I use my collet chuck to hold the workpiece - then the head of the spherical turning tool doesn't clash with the chuck so no clearance problem at all!
Title: Re: governors
Post by: jonesie on October 24, 2012, 04:23:13 PM
 :ThumbsUp:  jo i like up and over radius turner. do you have plans to build this or are they a copy right. if so do you have a site to buy the plans, been holding off building one , but i like this one and would like to build. thanks jonesie
Title: Re: governors
Post by: Jo on October 24, 2012, 04:52:00 PM
My drawings are copyright Hemingway 1993 but I believe that almost identical drawings are available from all over.

---------------

Last night I realised I had made a mistake :cussing: the two holes on each link need to be on the same side so first thing this morning I set about correcting them. First I turned four steel plugs the size of the offending holes:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1993.jpg)
I then silver soldered them in:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1994.jpg)

They clean up quiet well:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1995.jpg)

I then proceeded to mill the slots in the larger link. Before taking it to my Hobbymat lathe and milling parallel sections where the tapers will be on both links:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1997.jpg)

One of my complaints about the hobbymat is that the tool post and cross slide gets in the way when I want to support anything from the tailstock. So I proceeded inside to use the Cowell?s to turn the tapers on the smaller link:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_1999.jpg)

The taper has been hand formed I simply cut the two end diameters, then manually made a number of steps and merged them using a needle file.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2001.jpg)

I then returned to the hobbymat and set over the top slide and turned the tapers on the larger pair of links:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2002.jpg)

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2003.jpg)

Next job turn the centres of the two links the correct diameter to fit in the weights:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2004.jpg)

Now for a bit of filing. I thought you might find my ?fiddly bit vice? interesting. I made this up out of a locking ball join clamp with a toolmakers vice mounted in the socket. The result is a vice that can hold small bits in any orientation you may ever need.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2006.jpg)

The links are very fragile once the ends are broken so it is important to put a packing piece between the arms when you file or nasty things will happen:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2007.jpg)

Before filing the larger link it was necessary to bring the 6.35mm square down to a 4.7mm by 6.35 section on the end balls, 4.0 by 6.35 on the arms and 4.7 by 4.7 where the central pivots are:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2008.jpg)

So tonight two links still together:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2009.jpg)

And just to check they fit.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2010.jpg)

I still need to make the pivots, drill the weights and make the last two pairs of links.

-------------

That is it for today, this evening I am off to my Model Engineering Society to see if they are going to run a Rally next year.

Jo
Title: Re: governors
Post by: mklotz on October 24, 2012, 05:02:50 PM
If you're in the USA it may be simpler to just buy carbon steel balls from Enco.

http://www.use-enco.com/CGI/INPDFF?PMPAGE=804&PMITEM=240-2435

Sizes from 1/8 to one inch.  As you can see, they have them in stainless as well.
Title: Re: governors
Post by: Jo on October 25, 2012, 05:11:22 PM
 :disappointed: Not much to report today??I had to go  :paranoia: shopping.

I did manage a few minutes so I mounted the weights to the end of the drop links. The drilling was achieved by means of making a drilling guide that fitted over the weight?s collar. This was then used to align the weight for drilling by sticking the drill in the guide and making sure it was vertical. The weights were protected from damage by the vice using some off cuts of a soft drink can ;).

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2011.jpg)

The links were then split and the tangs shortened as required. Finally the balls have been attached with some very strong loctite.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2013.jpg)

Jo
Title: Re: governors
Post by: Don1966 on October 25, 2012, 06:22:32 PM
Awesome Jo, I like the way you make it all look so easy. I guess once you have done it some, it becomes second nature. I have an IC project that will require governor control and this is my class room till I get around to build it.  :praise2:

Don
Title: Re: governors
Post by: Jo on October 25, 2012, 06:56:51 PM
Thanks Don: I am pleased someone is still following along and finding it useful.

Next job is those thin links. I have been having a little rethink and am going to try a different way than normal ;)

Jo
Title: Re: governors
Post by: fcheslop on October 25, 2012, 07:03:38 PM
Sorry for not speaking up I'm kinda shy Definitely watching and learning :ThumbsUp:
Title: Re: governors
Post by: Captain Jerry on October 25, 2012, 11:18:27 PM
Thanks Don: I am pleased someone is still following along and finding it useful.

Jo

You are doing good work, Jo.  Lots of people watching.  I was watching to see how you were going to get the barrel shaped pivot at the mid point on those arms. Oh, like that! Note taken. 

Jerry
Title: Re: governors
Post by: steamer on October 26, 2012, 02:20:25 AM
Oh I'm writing it down as it comes Jo.....

Dave
Title: Re: governors
Post by: zeeprogrammer on October 26, 2012, 03:13:25 AM
I'm another someone!
I've been reading every post.
Title: Re: governors
Post by: Pete49 on October 26, 2012, 03:36:28 AM
and me too  :D Learning quite a lot from this.
Pete
Title: Re: governors
Post by: smfr on October 26, 2012, 06:16:46 AM
Yep, I'm reading every one! Keep going, Jo!

Simon
Title: Re: governors
Post by: Maryak on October 26, 2012, 07:39:15 AM
You've got my attention  :ThumbsUp: ................(difficult to write when your reading :Jester: )

Best Regards
Bob
Title: Re: governors
Post by: ProdEng on October 26, 2012, 10:48:23 AM
I am watching and learning :)  Looking at the end product I would have tried an improbable method but now know better :ThumbsUp:
Title: Re: governors
Post by: Jo on October 26, 2012, 03:23:28 PM
The spindly links ;D, I started off this thread by mentioning that we were going to do them enblock, this is how. These are our links:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2027.jpg)

We start with two blocks their top surface must be larger than the size of the link and we co-coordinate drill for the link holes:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2017.jpg)

We now mill the two flats on either side of our block for the shaft of the link:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2020.jpg)

Which gives us these:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2023.jpg)

Now using a slitting saw we cut slices the thickness of our link ;):

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2024.jpg)

Giving us lots of links, these are then rubbed on emery to get rid of the cutting marks.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2025.jpg)

We now knock up some filing buttons. For the larger links I files the ends in pairs, for the thin ones I did all four at once:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2032.jpg)

This gives us these ;D:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2033.jpg)

Next job is the pivots, then I will show you what they look like once they are put together. Then the job takes a turn for the worse.. painting :paranoia:

Jo

Title: Re: governors
Post by: ScroungerLee on October 26, 2012, 03:59:17 PM
I too am following along.  Originally I pulled up a chair, but had to get up for a minute.  When I got back Zee was sitting there.  I will just sit on the floor taking notes :)

Lee
Title: Re: governors
Post by: Dan Rowe on October 26, 2012, 04:33:41 PM
Nice way to make the links Jo. :ThumbsUp:

I see that you made enough stock to make extras.

Dan
Title: Re: governors
Post by: Jo on October 26, 2012, 04:55:53 PM
Thanks Dan,

I try to make extras of these little pieces as they are so easy to drop on the floor. Once there often the workshop gnome gets there first and hides them  from me :-\.

Jo
Title: Re: governors
Post by: Don1966 on October 26, 2012, 05:09:47 PM
Jo, I just never though of cutting the links out of solid stock like you did.   :slap: I would of found thin metal and cut them from that. Your way is better in that if you mess up just slice another one all shaped up and holes drilled. Great stuff to follow here. By the way this might be second nature to most of you, but hey when you don't know you don't know.  :happyreader:
Title: Re: governors
Post by: Jo on October 26, 2012, 05:21:48 PM
I would of found thin metal and cut them from that.

That is the way I have always seen it done before but when it came to my Lady S I knew that if I was going to stay  sane keep my patience I needed to find a different way ;) and it worked ;D.

By the way this might be second nature to most of you, but hey when you don't know you don't know.  :happyreader:

Hey I have no formal training (I do not count 2 days lathe & milling training during my apprenticeship), I make it up as I go along using the tools to hand. Not knowing how you should do something means that the possibilities, for success  :D as well as failure >:(, are endless.

Thanks for staying with us.

Jo
Title: Re: governors
Post by: arnoldb on October 26, 2012, 05:45:20 PM
 :ThumbsUp: Very instructive Jo - I've also been sitting glued to the seat following along.

A quick question - do you also use the slitting saw to slit off the pieces to _just_ before they are fully separated from the parent stock and then just break them off at the burr ?

Paint...  I knew there was something I forgot to get from the shops today  :facepalm2:

Kind regards, Arnold
Title: Re: governors
Post by: Jo on October 26, 2012, 06:17:38 PM
A quick question - do you also use the slitting saw to slit off the pieces to _just_ before they are fully separated from the parent stock and then just break them off at the burr ?

The slitting saw's action is fairly slow so you can wait for the piece to gently rise from the parent metal and know when it is about to part. At which point I stop, lift of the piece and and give the burr, which you will get either way, it a little rub with a needle file.

Jo
Title: Re: governors
Post by: NickG on October 26, 2012, 07:44:37 PM
Great stuff Jo, and thanks for the info on the ball turners - seems more versatile than the other sort I'd seen then.

Title: Re: governors
Post by: Captain Jerry on October 28, 2012, 05:25:43 AM
Jason had said that he would post a picture of his butterfly valve here but it hasn't showed up yet so I hope this is a gentle reminder.  I think that a butterfly valve is a good choice for a throttle valve controlled by a governor because it is balanced in the air stream and has much less friction than the barrel type and this is very important if you hope to get any real control with a small scale governor.  I have heard people avoid them because most designs require you to fit the plate to the shaft while it is inside the valve body and the difficulty of access and the insecurity of the resulting assembly is a concern.  I have been thinking about the problem and it seems to me that an easy way to build a butterfly valve is to make the valve body a two piece assembly, split at the shaft location.  The shaft and plate can be assembled in the light of day, with good access for adhesive or solder and the installed between the body halves which can the be bolted together.

Here is a sketch of my idea that should be easier to understand than my description.  It is only a concept sketch and the style can be altered in lots of different ways to suit your design.  Is this original or have I just forgotten where it came from?

The attachment is a 3D PDF which you can rotate.  You have to click on the "Activate" button in the upper right to do this.

Jerry
Title: Re: governors
Post by: Jasonb on October 28, 2012, 08:04:55 AM
OK, I can take the hint ;)

Its been a few years since this part saw the light of day and the duster for that matter.

This is a general view of the regulator casting that bolts onto the valve chest and the steam entry flange.

(http://img.photobucket.com/albums/v156/jasonballamy/Engineering/IMAG0987.jpg)

As Jerry's drawing shows the has a slot down its length, the angled slice off the rod fits into the slot and is held in place with a 1/32" rivit in this case though a small screw may also work.

Closed
(http://img.photobucket.com/albums/v156/jasonballamy/Engineering/IMAG0988.jpg)

Open
(http://img.photobucket.com/albums/v156/jasonballamy/Engineering/IMAG0993.jpg)

Sorry I can't take the butterfly out as its rivited but Jerrys sketch shows whats going on.

J
Title: Re: governors
Post by: smfr on October 28, 2012, 03:28:54 PM
Thanks for posting, Jason! It's useful to finally see inside of of these. I have a feeling we might need a new thread on valves soon.

Simon
Title: Re: governors
Post by: Jo on October 28, 2012, 04:06:42 PM
Last part for the governors: the pivots. These are simple male and female pins which press together. For the larger engine the females have a 2.4mm shank, with a 1.6mm hole drilled part way through it, the smaller engine has 1.6mm shanks with 1.0mm hole drilled part way through it. Normal rules apply drill the hole then turn the shank to avoid the shank becoming over sized when you drill it. Be careful when you finish the heads because the smaller pins only have 0.2mm thick walls and can be easily crushed. 

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2037.jpg)

The pins should be a press fit but there is nothing wrong with some insurance some superglue or loctite just be careful where it goes. So finally assembled we have two governors:

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2040.jpg)

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2043.jpg)

Mounting on the larger engine?s base it I would say the governor looks ok.

(http://i214.photobucket.com/albums/cc12/jothoms/Governors/IMG_2044.jpg)

For information:I will be doing one of the longer links that goes to the throttle valve on my Double Tandem Compound thread  8) so I did not intend on repeating it here.

Hope there was something of use in this thread. ;)

Jo
Title: Re: governors
Post by: chuck foster on October 28, 2012, 05:24:02 PM
Quote
Hope there was something of use in this thread. ;)

Jo

jo you are one person who NEVER has to hope about their thread being of use !!!! every thing i have read from you is always a great read and to that i say THANK YOU  :cheers:

chuck
Title: Re: governors
Post by: Jasonb on October 28, 2012, 05:55:19 PM
Very nice thread Jo. Now if you could just add the Bevel Gear cutting your job here will be complete ;)

J
Title: Re: governors
Post by: Jo on October 28, 2012, 05:58:59 PM
Sadly I have to go back to work tomorrow :ShakeHead: . So it may be a while :-\

Jo
Title: Re: governors
Post by: Maryak on October 28, 2012, 09:38:45 PM
Thank you Jo  :praise2:

Best Regards
Bob
Title: Re: governors
Post by: Don1966 on October 29, 2012, 01:40:45 AM
Jo, I had posted earlier on this thread, but it seemed to have disappeared. I wanted to thank you for your very informative thread. I enjoyed you class room and have learned plenty. You thread is always here for us to reference to. I do hope as Jason has said, whenever you have time to show us how to build the bevel gears associated with the governors.

Don
Title: Re: governors
Post by: Jo on October 29, 2012, 02:26:17 PM
Cutting bevel gears is "easy" ;), making the right shaped cutter to do the cutting is where the challenge is.

Jo
Title: Re: governors
Post by: Jo on October 30, 2012, 01:37:18 PM
 :pinkelephant: :pinkelephant: :pinkelephant:

I have just rescaled from my photo's the bevel dimensions and the gear for the 1/6th scale engine needs to be slightly larger than I thought, the one I need has a 17.5mm OPD so I can get way with a No 4 32 DP cutter.

Whilst I have it set up I may as well cut the ones for the Armstrong as they are the same size ;D. I think I already have the required cutter in my collection :whoohoo:

Jo
Title: Re: governors
Post by: Dan Rowe on October 30, 2012, 08:47:27 PM
It is always good when you already have the correct tool.

I am looking forward to the bevel gear cutting write up. :ThumbsUp:

 :cheers:
Dan
Title: Re: governors
Post by: Don1966 on October 30, 2012, 11:36:17 PM
I am glued here to Jo. I find it very interesting.

Don
Title: Re: governors
Post by: Pete49 on October 31, 2012, 01:25:55 AM
As do I Jo. Let it rip we have popcorn and seats
Pete
Title: Re: governors
Post by: Jo on November 09, 2012, 04:34:49 PM
Bevels. The only difficult thing about bevels is the maths :ShakeHead:  in the end I found what I needed to cut the bevels for the 1/6th S&T. (I suggest you put the equations in a spreadsheet and let that do the calculations for you. :naughty:) These are 45 degree straight cut bevels, also known as mitre bevels which simplifies the maths for us. I need 16 tooth bevels, of 32 DP.

Face angle = pitch angle = cutting angle = 45 deg.

Inner pitch diameter  = no teeth / DP of the cutter = 12.7
Outer pitch diameter = 1.4* inner pitch diameter = 17.8
Inner cone length = Inner PD * (2 * Sin Pitch angle) = 8.9
Face length = 0.35 * inner cone length = 3.144
Blank diameter = Outer PD + (2 cos pitch angle / DP of cutter)

Cutter number for pinion = (no teeth in pinion * 1.25) / COS pitch angle = 28 teeth

Did you notice the number of teeth we have calculated is different than the number of teeth we will have in the gear! 28 teeth means a number 4 cutter profile, which I have.

Cutter offset = 3.142 / (4 * DP of cutter) = 0.623

Next job we need to think about the dividing head we are going to use, the one I used for this has a 40:1 ratio worm. What I need is to be able to divide by 16 teeth * 4 = 64, so looking through the dividing plates I found one with 16 holes that will give me a division of 640. So divide by 64 = 10 holes, divide by 16 = 40 holes. The sector arms were set for 10 holes.

We are ready, so first job cut two lengths of bar that will fit in the dividing head and cut the profile

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2047.jpg)

Ok off to the mill, I have set the dividing head up at 45 degrees, lined up the centre of the correct cutter with the blank and we are ready to take our first cut:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2156.jpg)

First job setting the tooth depth, this is easy take the cutter up to the blank until it just touches, zero the DRO and wind in the depth of the tooth. It is now a simple job of winding the y axis in and out, moving the dividing head around 40 holes and making the next cut? What you end up with is this:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2160.jpg)

Now comes the important bit, we are now going to move the dividing head back 10 holes which is a quarter of a tooth width and we are going to change the height of the cutting head by our calculated cutter offset 8).

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2163.jpg)

The offset must be applied in the same direction that the bevel has just rotated. And we take a second cut all around.

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2164.jpg)

We then reverse the offset so that we are taking a third series of cuts but on the other face of the tooth to that which we just did. For this I rotated the dividing head by 20 teeth and offset the head the 0.63mm in the other direction. To avoid getting confused with my counting I have taken to marking up the holes that the pin should end up on on the dividing head with marker:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2165.jpg)

An aching arm later and I have cut the first pair of bevels:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2166.jpg)

So now back to the lathe to cut the rear 45 degrees and to part off:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2167.jpg)

So two bevels, you may note I have a third cut, this shows the problem with straight cut bevels you are limited to how much you can cut towards the centre before you start cutting into the adjacent tooth:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2168.jpg)

So a pair of Bevels as promised:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2169.jpg)

My arm is telling me no more today ;).

Jo
Title: Re: governors
Post by: Dan Rowe on November 09, 2012, 05:17:01 PM
Jo,
Very nice write up on the bevel gears. :praise2: :praise2: :praise2:

The only thing I would like to add is the method that was used is known as the parallel depth method also sometimes known as the uniform height tooth method.

Dan
Title: Re: governors
Post by: Don1966 on November 09, 2012, 05:18:48 PM
Jo! Thanks for the gear class,  :NotWorthy: but I think I am still confused.  :headscratch: I will have to reread Ivan Laws book on Bevel gears. :happyreader:  Last week I ordered the book Gear Design Simplified just to cover all my bases. I would say that the cutting angle is what I just can"t get a hold of. If you cut the Bevel at 45 degress and aligned your cutter for 45 degrees would not the slot in the gear be the same depth along its length, looking at your gear they don't seem to be? Mybe its the photo angle. :headscratch:

Don
Title: Re: governors
Post by: Jo on November 09, 2012, 05:23:55 PM
You are right Don these are parallel cut bevels so they are the same depth for their entire length ;).

I had been working from Ivan's book but got confused trying to find the tooth depth and the offset distance. So ended up finding an article in ME that gave these measurements.

Jo
Title: Re: governors
Post by: Dan Rowe on November 09, 2012, 05:27:29 PM
Don,
It is an optical illusion. The photo of the gear in the lathe is cutting the back cone which is usually 900 to the face of the gear.

The small end of the gear is not cut 900 to the face of the gear so that throws off the eye.

Dan
Title: Re: governors
Post by: Don1966 on November 10, 2012, 04:15:15 PM
Thanks for the reply Jo, and thanks Dan I had thought it might have been. I am still trying to grasp this. I read read Ivan Laws book on Bevel gears but that part is a little vague and does not cover very much formula wish. Just angles and layout. I need formulas to do a spread sheet with.

Don
Title: Re: governors
Post by: Jo on November 10, 2012, 04:17:58 PM
If someone can explain how to attach an excel spread sheet to the forum I would happily make my noddy one available ;).

Jo
Title: Re: governors
Post by: Jasonb on November 10, 2012, 04:34:28 PM
If you cut the Bevel at 45 degress and aligned your cutter for 45 degrees would not the slot in the gear be the same depth along its length, looking at your gear they don't seem to be? Mybe its the photo angle. :headscratch:

Don

Don the slot cut by the cutter will indeed be the same depth and width along the whole face of the gear BUT the bit left between the cuts will get wider the further it is from the centre so won't fit in the matching slot in the other gear that is why the slot needs to be made wider the further it is fron ctr. If taht doe snot make sense I'll sketch it out.

J
Title: Re: governors
Post by: Don1966 on November 10, 2012, 04:54:19 PM
Jason I understand that the tooth width gets bigger from center. Is the slot cut bigger from the center or is it the same width as the spur gear cut?
Jo, you should be able to attached by the attachment be low the reply.

Don
Title: Re: governors
Post by: Jo on November 10, 2012, 05:02:52 PM
Don, The problem is that I can't get photobucket to accept an excel spreadsheet :hammerbash:.

I cut the slot from the wide end of the tooth to the narrow. The tooth width in the center is the same as a standard spur gear, but equivalent to a 28 tooth spur rather than 16 tooth.

Jo
Title: Re: governors
Post by: Don1966 on November 10, 2012, 05:20:47 PM
Jo, the attachment and other sheets below your reply gets it from your computer. Just insert it there.

Don
Title: Re: governors
Post by: Jo on November 10, 2012, 05:28:17 PM
Second attempt...

Jo
Title: Re: governors
Post by: Don1966 on November 10, 2012, 05:38:19 PM
Thanks Jo I got it. I seem to be getting a error in cell E 18 blank width.

Don
Title: Re: governors
Post by: Jo on November 10, 2012, 05:44:10 PM
Mine is ok :noidea: column E is just a repeat of column D. I added it so that I could use the sheet for bevels other than mitres. But have not done the maths yet.

Jo
Title: Re: governors
Post by: Don1966 on November 10, 2012, 06:29:49 PM
Jo, you formula references to cell D9 but the D9 column has .707 in it and E9 column has nothing. I think it it suppose to be in D and E10 pitch angle of wheel. Can you verify this for me. I found the problem with E18 there was a F6 attached to it. This may be some kind of conversion problem on my part. I am using my IPAD and a office suit other then Microsoft.

Don
Title: Re: governors
Post by: ScroungerLee on November 10, 2012, 06:34:56 PM
Thanks for the write-up Jo.  This is one of those cases where my getting a little knowledge shows me how much i don't know :). Good thing I enjoy learning new things.

Lee
Title: Re: governors
Post by: Jo on November 10, 2012, 06:47:12 PM
Jo, you formula references to cell D9 but the D9 column has .707 in it and E9 column has nothing. I think it it suppose to be in D and E10 pitch angle of wheel. Can you verify this for me. I found the problem with E18 there was a F6 attached to it. This may be some kind of conversion problem on my part. I am using my IPAD and a office suit other then Microsoft.

Don

0.707 is me being lazy it is the sin and cos of 45 degrees. I directed column e to d because I need to add the appropriate maths for pairs of unequal bevels but have not done it yet. Ignore the f6.

Jo
Title: Re: governors
Post by: Don1966 on November 10, 2012, 06:52:29 PM
Thanks Jo, could you repost it once you complete the Unequal Bevel formulas?

Don
Title: Re: governors
Post by: zeeprogrammer on November 10, 2012, 10:25:31 PM
Nice thread on making bevel gears. Thanks.
Title: Re: governors
Post by: Jo on December 16, 2012, 03:41:45 PM
I must apologise when I first discussed making governors I very briefly mentioned making long links out of two pieces without explaining the technique for making them, what I am going to describe is making the governor to regulator link for my Double Tandem Compound engine:

This is my drawing for this link:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2321.jpg)

We will start on the fork, for this I took a piece of 3.2mm scrap and cut from it a piece 8mm wide and 16mm long.

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2295.jpg)

The first cut is to make the slot for the main arm, this was done using a slitting saw:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2296.jpg)

The width of the cut was checked with the shank of a drill. Then off to the other mill to have two holes drilled:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2297.jpg)

You can see that the hole we want is very close to the slot that was cut, the other is to give us something to drop this milling cutter into:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2298.jpg)

So using a slot drill the two holes are joined together. Now we use filing buttons to shape the back of the fork, we don?t want to touch the other end because we need the waste material to hold it together:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2299.jpg)

This is what she looks like once she has had a little fettling with some files:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2302.jpg)

Whilst she is in the vice I filed the top and bottom tapers on either side and the first half of the end rounding, then as much of the second half before I had to finally part it from the waste. So one fork end that fits the material I am going to use for the main arm:
 

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2303.jpg)

The main arm is first drilled for the pivot and end attachment. Then it is shaped up using filing buttons inserted in these two holes:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2304.jpg)

After a bit of character building this is the two parts:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2305.jpg)

We are now going to silver solder the fork to the arm. This is done by making sure some damp flux fills the slot in the fork end, adding flux to the end of the arm and balancing a small piece of silver solder above the joint:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2306.jpg)

Apply some heat:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2308.jpg)

And the joint is made. It is then back to filing to join the two profiles and some polishing:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2309.jpg)

The link is put on to the governor, with a washer and a home made R clip:

(http://i214.photobucket.com/albums/cc12/jothoms/Double%20Tandem%20Compound/IMG_2320.jpg)

I would have normally used a single ring from a spring but I had already drilled the governor pivot for an R clip.

You can see what she looks like on my Double Tandem Compound thread.

Jo
Title: Re: governors
Post by: Bearcar1 on December 16, 2012, 04:09:45 PM
Nicely executed Jo, well done indeed.  :ThumbsUp:


BC1
Jim
Title: Re: governors
Post by: sierrasmith71 on February 04, 2018, 11:13:50 PM
Any hope of getting the Photobucket links fixed so we can see the photos?

Thanks in advance
D. Garrison
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