An Upshur Farm Engine (first I.C.)

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Mike,
Thanks for that. I had heard that magnet trick before, and for some reason, had been skeptical. When you explain that the point at which the metal becomes non-magnetic and the transformation temperature are not exactly the same, and in fact differ significantly for some alloys, that makes it much
clearer (and much more believable intuitively). I will definitely try it the next time.

--Tim
 
Still more work on the head. The plans show the upper edge rounded over, and
though it seemed a little late in the game, I decided to go ahead and do it.
In my 4-jaw Taig chuck on the rotary table, I centered things up and used a
corner-rounding bit on it. Uneventful. Job done.

130.jpg


To lap the mating surface with the cylinder, I laid wet-or-dry paper on my
little granite block and scrubbed in a figure-8 pattern (where did I read that
thing about the figure-8 pattern?). I worked down through 150, 320, 400, and
600 grit to get to the point you see in the first picture. 600 is the finest
I had. I laid a sheet of paper down on the granite and then squirted out a
blob of toothpaste, then lapped some more. The second picture shows the
result. The camera really brings out scratch marks, and I'm hard pressed to
pick out any in that second picture.

135.jpg

140.jpg


Before I proceed, I wanted to make up a little pressure testing fixture to
test the valves. I used the squaring fixture I'd made for drilling side holes
in the head. I milled out a chamber for the valves to operate in and drilled
and tapped for a small pipe into the chamber. I have pipe, taps and dies at
3/16-40, which is the thread PM Research use for small steam engines.
I lapped the mating surface of the plate like I did the head.

145.jpg


I hope this helps me nip any sealing problems in the bud early on. This shot
also shows that I made and installed a plug for sealing up the outer end of
the cross hole made for creating the right-angle bend in the sparking hole.
That leaves only the rocker arm post hole to fill.

150.jpg


Thanks for your vigilance,
--Tim
 
If it helps, Joe Tochtrop has (or at least had) a nice 1/4"-40 miniature Champion spark plug. They seemed to be less prone to fouling than homemade surface gap plugs, and weren't all that expensive.
 
The test fixture is a good idea, you can use soapy water as a "leak detector". Also makes it possible to test the piston/cylinder seal. Another idea for my notebook :)

Jan
 
For the rocker arm post - even though I (think) I had followed the plans exactly, the post seemed to stick out just a little too far. Before you Locktite it in, you may want to check how the rocker and post assembly will interface with the valve stem. Mine still works ok but I would have expected the rocker arm to be parallel with the head but it was slightly off.
 
Tim

I like the idea of the pressure testing fixture (KP for that). Have you used it yet?

Vince
 
Dennis, thanks for the heads-up on the rocker arm post length. I just checked, and indeed the numbers don't seem to add up right.
Does your post seem to be about .063 short?

Vince, I've not yet used the pressure testing fixture. I still have to cut the seats and install the rocker arm post. And I'm awaiting the delivery of some springs.
When I use it, you all will be the first to know!

--Tim
 
tvoght said:
Dennis, thanks for the heads-up on the rocker arm post length. I just checked, and indeed the numbers don't seem to add up right.
Does your post seem to be about .063 short?
--Tim

Actually, mine came out a little long. :) Headset problems, no doubt.

I looked for a picture that shows the angle I was dealing with but this is the best I could do. Kinda hard to see. There was about a 15 degree angle relative to the head so I punched out the post and put in a new one.

020.jpg
 
I know this thread has long ago closed, but can someone point me to the source of the plans for the Upshur engine? Are they from "Strickly I.C."?

Thanks,

Alan
 
I know this thread has long ago closed, but can someone point me to the source of the plans for the Upshur engine? Are they from "Strickly I.C."?

Thanks,

Alan

And I should have mentioned that they are extremely good value. The farm engine plan set, for only $10, allows you to build 4 variants, either air cooled or water cooled and horizontal or vertical. All variants can be hit and miss or throttled. This was my first I.C. engine and I managed to get it running even without any skills at all at the time. One of these days I'll have another go and make one which does the design justice.
 
Ordered on PayPal, the acknowledgement had a link for the download. but it took me a week to notice it.

Thanks.


And I should have mentioned that they are extremely good value. The farm engine plan set, for only $10, allows you to build 4 variants, either air cooled or water cooled and horizontal or vertical. All variants can be hit and miss or throttled. This was my first I.C. engine and I managed to get it running even without any skills at all at the time. One of these days I'll have another go and make one which does the design justice.
 
I have also purchased the plans, just make sure you actually save them to your computer. They send you a link to open the plans and then after so long the link will go dead, well mine did anyway. Saying that though they were more than happy to resend me the link again.
I've been looking at building the aircooled version and got excited to see this thread as i havn't seen anyone building one yet. Then i realised this thread was back in 2012! Oops.
 
Yeah, I was so happy to find the thread, that I took a chance and posted. My old prints from buying the metal kit weren't that readable (and limited).
I need to get building!
So many projects, so little time.

I have also purchased the plans, just make sure you actually save them to your computer. They send you a link to open the plans and then after so long the link will go dead, well mine did anyway. Saying that though they were more than happy to resend me the link again.
I've been looking at building the aircooled version and got excited to see this thread as i havn't seen anyone building one yet. Then i realised this thread was back in 2012! Oops.
 

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