Eastern and Anderson Grasshopper Beam Engine

[Jo]

This last weekend I have just finished off my Eastern and Anderson Grasshopper Beam Engine, which had for many years sat on my book shelves looking rather sad:



In the main the castings were no problem to machine, what stopped the original build was the need to make a number of long thin spindly items which having attempted a number of times I made the decision that I was not ready for. Time moved on and now the parts have been completed. The tricky spindly bits included such joys as a connecting link 2 ?? long and only 2.4mm diameter:



These were actually cut on my Cowells Lathe between centres, the bearings and end caps being made as turned disc which were super glued to the main link before putting in a machine vice and the faces machined flat and holes drilled/reamed using the DRO to get the lengths correct. 

Another tricky bit was some 1/16? dia valve links. In the end these proved fairly straight forward and all followed a similar process, so to give you an idea this is how I did these links:



Starting on my milling machine I used the DRO to accurately position the centres of the two holes before moving on to my BCA to mill the flats to width:



My Cowells Lathe made cutting the 1/16? shaft a breeze:





Next job was to turn shoulders on each of the faces:





Before a bit of hand filing using filing buttons, super glued in place during the filing operations. These are the resulting links (the photo was taken before polishing ).



I?ve got a few more photo?s of making some of the other tricky bits if anyone is interested.

Jo

[Bogstandard]

It is so nice to see you posting here Jo, I was looking forwards to seeing this engine finished off and running.

Like yourself, I find fiddly bits like this rather challenging, but it looks like your efforts really paid off this time.

John

[Dan Rowe]

Hi Jo,
The small tricky bits are often the most interesting parts to see how to make. I would love to see the rest of the build photos.

Dan

[Jo]

The governor was an interesting build:



Most of it is simple turning, for instance the main body is made simply from brass stock and consists of three parts silver soldered together, this cross section explains a lot of the make up:



However the Governor top was a tricky bit:



Originally I thought that I had lost the casting but on further investigation I found that it needed to be made from bar stock. The important thing to note is that this part requires to be threaded squarely with the governor body so it is necessary to first make the body, then taking a piece of ?? brass bar turn and thread it fit the governor body. Once screwed together both embryo cap and body are taken over to the mill and the cavity milled and the drive shaft spindle hole drilled.



The cap now goes back to the lathe and the cap is shaped up,


and the top taper was turned.



I now realised that I had missed a trick and took the cap back to the mill and squared up the cavity and a bit of careful filing to get the various curves looking better?.and then parted it off.  The cap was then turned around and the top drilled to take the cap and balls. The bearing for the drive shaft spindle was a simple brass turning silver soldered to the side of the cap.  This is the final cap in position on the governor body.  (Oops I forgot to take a photo after the drive shaft bearing had been solder on the side, sorry)





The weight arms were a bit of a cheat, I took three 3/16? ball bearings heated them up to soften them, made a simple arm similar to have the link I described earlier and then silver soldered them together.

The bevels were very simple as on this engine it is only a case of, as they say, making to balls go round, rather than controlling the engine. They were  made by first profiling 4 ends  (2 + 2 spare) of a bit of 8mm stainless to match the gear shape, then these were taken to the mill the dividing head set to the gear angle and then each tooth was cut using a piece of broken centre drill ground to a taper, the curves formed by hand so that the gears ran smoothly. Back to the lathe one gear was tapped 10Ba for the drive shaft and the second was drilled 2.4mm for the vertical column:



The parting off of the gears was done on the Cowells using its Sherline 4 jaw self centring chuck.

Jo

 

[Bogstandard]

Jo,

I am glad to see you make gears how I do.

Only sometimes do they need to be perfect, in which case, they would be purchased, most other times, as long as they run smoothly together, then they will do the job admirably.

I think that when beginners see gears in a build, it puts them off a bit, as they can sometimes be very expensive to buy, but with a little knowledge and patience, they can in fact fairly easily make their own, as Arnold is showing in his superb post.

http://www.modelenginemaker.com/index.php/topic,195.0.html

John

[dsquire]

Jo

Very interesting  how you made some of the smaller items. Lot's of patience required. Thanks for showing them to us.

Cheers 

Don

[ironman123]

What Don said.

Ray

[Jo]

The governor also required a small hand wheel. I have tried various ways over the years and as the size gets smaller they get harder to make something that I am happy with. I have now found a way that works (for me), so this is how I made the hand wheel for the governor shut off valve:

The requirement was for a hand wheel 9/16? in diameter, so the starting point is to chuck a piece of 9/16? in the collet chuck and using a rose bit to turn a ?groove?. The rose bit is just the right outside diameter to leave an appropriate rim width and a 1/8? centre. What is important here is that you must make the groove deeper than the hand wheel, the extra depth provides somewhere for the excess silver solder to run into and space to part off:



Now over to the mill and using a dividing head drilling first with a centre drill and then using a (0.8mm) drill the centre hub. Warning! Do not attempt to go all the way across these small drills wander all over the place.





Many years ago I picked up a container of various different very small diameters of brass rod from this three length was cut the first passing right across the hand wheel the other two joining at the centre:



These spokes are then silver soldered into place, and because there is sufficient space under the spokes the excess silver solder flows away. (The mess is only the remains of the soldering flux.)



Having filed off the protruding ends of the spokes it is now back to the collet chuck, first re-drilling out the centre hole before parting off. It is important that your parting off tool parts off first immediately at the back of the hand wheel otherwise you will get bent spokes as they are not man enough to take any strain.



Last stage is to broach the centre square. To do this I use a piece of case hardened 1/16? sq BMS, lightly pressed through.





It fits a treat onto the 1/16th square shaft and is secured with a 12BA washer and nut.
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If anyone has any good idea about how to make Small washers I am all ears! I am having no end of problem finding a supplier who will provide the very small size (10BA/12BA) Steel washers. I have been thinking about using fizzy drink cans as my material, OK it is not steel but should be easy to cut and if it can survive Coke it will survive anything.

Jo

[Bogstandard]

Jo,

They only resist the coke because they are plastic coated on the inside.

So not only are you drinking the foul brew, but also all the plastic chemical residue as well, no wonder it tastes weird.

Great work you are showing here BTW.

I have great success making tiny washers and spacers by parting off. I grind up my own parting tools on the surface grinder that are about 0.010" thick, and they seem to last much longer than normal parting tools.

John

[b.lindsey]

Beautiful work all around Jo...am looking forward to seeing the finished pictures of this fine engine!!

Bill

[NickG]

Yes nice work Jo, an interesting project.

I've been looking at beam and half beam engines over the last couple of months considering buying a casting set. I'm sure I came across the castings for your engine but can't remember where!

Nick

[Jasonb]

Bruce Engineering in the UK sell the castings and drawings. for the build article it's best to buy Anthony Mounts book Vol II as this is basically a reprint of the magazine series.

I've made a start on this engine but am making it from scratch but at double the size.

J

[zeeprogrammer]

Very much enjoying this thread.
Interesting and a source of learning for me.

[NickG]

Ah that was it Jason, thanks will have to have another look.

There is a large set of castings at Brunell that caught my eye too, seem quite a bargain for the size and look like a nice engine.

Nick

[Jasonb]

There are a lot of bad reports about Brunell but also some good ones best to order in person not via the website.

J