Author Topic: Clarkson Twin Horizontal Steam Engine  (Read 2176 times)

Offline Jasonb

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #30 on: October 05, 2018, 01:23:48 PM »
The idea started on ME where 4 bearings was being questioned so the "argument" was about that, I just said it would not take much for anyone with a set to convert to 2 bearings. What is in those couple of photos is the minimum amount of work that even a relative beginner could carry out.But as you say if you are going to pay 250 for the set and then throw some away it will be cheaper to start from scratch which you could probably do for 100-125.

Phil, a new base would allow the length to be stretched a bit so the conrod did not reach such a steep angle, turned rather than flat would also gain a bit of clearance and so the list goes on and before you know it you will have a mini Agnes sitting infront of you :LittleDevil:

Anyway must go now as someone sent me some more equipment to try out and I get to keep it :pinkelephant:

Offline Jo

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #31 on: October 05, 2018, 01:34:30 PM »
The idea started on ME where 4 bearings was being questioned so the "argument" was about that, I just said it would not take much for anyone with a set to convert to 2 bearings. What is in those couple of photos is the minimum amount of work that even a relative beginner could carry out.But as you say if you are going to pay 250 for the set and then throw some away it will be cheaper to start from scratch which you could probably do for 100-125.

Anyway must go now as someone sent me some more equipment to try out and I get to keep it :pinkelephant:

Mike didn't pay anything like that for his castings  :lolb:

I hope it is a CNC Milling machine  :ThumbsUp: I seem to recall Ketan had a spare one of those kicking around... I have lots of space so I would happily have given it a home instead I will have to settle for my new toy when it turns up next week  :naughty:

Jo
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Offline Jasonb

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #32 on: October 05, 2018, 03:11:53 PM »
I was going by the current price list, expect the missing ones he paid pro rate the current price for.

Not a CNC I turned that down when it was offered to me a couple of years ago though could be tempted now. He seems to be spending all his time playing with tehnew SX3.5 DZP if the number of videos he keeps sending are anything to go by, has quite an impressive cut and certainly shifts metal when run at 5000rpm. Hoping he may offer me that as it has got bright red handwheels :P

This came from japan via another supplier :-X

Offline Jasonb

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #33 on: October 06, 2018, 08:10:07 AM »
For those that don't like the afterthought slot in the trunk guides a simple turned and tapered conrod going from 1/4" diameter at the big end to 3/16" at the other will clear the guide.

I have not drawn the big end but if making it would press/loctite in a bronze bearing as a minimum, maybe even do a full marine big end

Offline Mike Bondarczuk

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #34 on: October 06, 2018, 01:27:48 PM »
Hi Jason,

You are providing lots of food for thought with the redesigns, some of which are significant and in keeping with the concept of the castings and some which are a bit more dramatic, such as going with a two pedestal bearing support system rather than the four, which I shall stay away from.

For the conrod bearings I have stayed with the design but added an oil cup at the top of each con-rod and this will keep things nice and smooth and I shall not be running the engine for any significant length of time and only on compressed air, so don't think that will be an issue.

I do like the suggestion of increasing the tapers from the original 5/16" thick end down to 3/16" at the thin end to 1/4" thick to 3/16" thin and may well do so as having made the con-rods already it is not a difficult task to set them up again and do some more milling on the profiles.

I shall make a final decision once I have received the trunk guides, and hopefully machined them to the correct sizes and then check whether I have a striking conflict at the thin end and agree that the slots are an afterthought and do not look quite right.

I am currently working on the con-rod, valve rod and slide valve family and will post pics once completed, which should be in the next day or so, depending on the weather.

Mike
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Offline Jasonb

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #35 on: October 06, 2018, 04:17:42 PM »
Yes it should not be too hard to add the taper to yours, should come out something like this though I have shown the big end hole 1/16" larger for a bearing.

One thing that would be worth thinking of on your trunk guides is taking a small cut where the nuts will bear on so that they are all sitting on a flat surface. It looks like the flange is thick enough so you could take 1/32" off and still keep to the drawings 1/8" flange thickness. The length of the trunk guide is missing off the drawing though the dimension line is there, if you make this 2.406" that should clear the conrod.

If you also fancied plunging into the top of the trunk guide just enough to form a 1/4" dia recess then a small disc could be JBWelded in and when set use a BS0 ctr drill to form an oil point. You could even make the disc a bit thicker and thread it for a small brass oil cup but just depends on how far you want to go.

Finally coat in bright red paint and you should have a much more attractive trunk guide than the original but still making use of the casting.

Offline Mike Bondarczuk

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #36 on: October 06, 2018, 04:44:25 PM »
Jason,

Once again many thanks for your input and the length dimension for the trunk guide is indeed missing from the drawings so I am most grateful for the information.

For lubrication I had already decided to spot face the trunk guides about mid point and tap and fit an oil cup, and I prefer oil cups rather than oil points, but that is just my personal preference.

My con-rods are rectangular rather than circular, but that was just my interpretation from the drawings, though having said that it would have been easier to turn them rather than mill and file them.

Mike
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Offline paulrayner

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #37 on: October 10, 2018, 08:27:06 PM »
Hello all
been a lurker for a bit and now I may be able to help
I have the drawings for the single cylinder mill engine which I think is one half of this one.
 I acquired the drawings from blackgates about 12 months ago and they are photocopys of the clarksons ones.
the trunk guide has a dimension of 2 7/16".
hope this helps
regards
Paul

Offline Mike Bondarczuk

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #38 on: October 11, 2018, 08:18:40 AM »
Hi Paul,

Interesting information as my original drawings do not show any dimension for the length of the trunk guide and Jason has suggested a length of 2 13/32" and now your numbers are throwing up 2 7/16", which is only 1/32" out so within operational limits I think.

More progress updates will follow later today.

Mike
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Offline Mike Bondarczuk

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #39 on: October 19, 2018, 05:40:42 PM »
Hello all,

Safely back from the Midlands Model Engineering show and am now in a position to start organising the work plan for the machining of the castings and build the Clarkson engine, and am attaching a couple of pictures of the new castings from Blackgates and the now complete collection.

Mike
"Everything I can't find is in a totally secure place"

Offline Jasonb

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #40 on: November 26, 2018, 02:14:18 PM »
Hi Mike, having had cause to look at my Clarkson drawing today got me wondering about your progress, is there anything to report?

J

Offline Mike Bondarczuk

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #41 on: November 28, 2018, 03:41:27 PM »
Hi Jason,

I have indeed been quiet of late, but have also been rather busy with my new vertical mill and generally cleaning up and re-organising my workshop, but have found plenty of time to generate swarf from the castings received from Blackgates, complete with hard spots.

This first post will show the progress on the steam chest and covers and the chest castings were undersize so I had to make some accommodation for the shortfall in their height as well as some changes to the inner dimensions of the chests as well.

I am not sure that my process flow or holding was the best but all seemed to go OK though I still have to drill and tap for the exhaust systems as well as the inlets, which will be of the quick release plastic push fit tubing type with flow controllers built in.

The next posts will contain updates regarding the next steps in the build process.

Mike
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Offline Mike Bondarczuk

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #42 on: November 28, 2018, 03:49:41 PM »
Jason,

In continuation the next parts for manufacturing were the cylinders and the crank assembly for the valve drive system and the castings for the cylinders had a few hard spots but also had a generous overage in all dimensions, which proved to be very handy.

Trying to work out the correct flow for machining took quite a long time and also workpiece holding was an issue when turning so I had to resort to packing pieces to ensure a good spread of tension as well as security.

I didn't wait for the cast iron to vie delivered from Blackgates so used some cold rolled steel bar I had to turn down to size for the crank discs and rods and associated pins, and I do try to use collects as much as possible by turning down to the largest 5C colletI have, which is just over 1 1/8" mange to do all the turning quite easily by holding the turned spigot.

Mike
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Offline Mike Bondarczuk

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #43 on: November 28, 2018, 03:58:38 PM »
Jason,

The next steps were to turn to size the end covers and gland nuts for the rear covers.

The castings were rather rough so I had to generate a reference dimension, turn down to a size and then based on that spigot do the rest of the turning and drilling. I suspect that this may not be the best way to operate but for me it seemed to work out OK.

The only deviation from the plans was that the bore is listed at being 1" which leaves no clearance for eh air borings so I reduced to bore down to 15/16" and made the locating spigots on all four covers to match.

The pistons are not turned yet so I will have to make sure that I get a nice sliding fit when those are being processed.

To ensure concentricity between the covers and the threaded holes in the cylinder I used a rotary table for the covers and then used the co-ordinate method for the cylinder and took turns at one hole at a  time for drilling and tapping, and can confirm that all went rather well and seems to fit very well.

Mike


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Offline Mike Bondarczuk

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Re: Clarkson Twin Horizontal Steam Engine
« Reply #44 on: November 28, 2018, 04:02:43 PM »
Jason,

One last picture of the front end covers bolted to the cylinder and also am attaching a couple of pictures of the base plates, the condition of which may mean that I just make a common baseplate and manufacture different bearing pedestals which should overcome the height issue already discussed with you.

The next post will be related to the trunk guide and I shall be asking for assistance in how to proceed.

Mike
"Everything I can't find is in a totally secure place"