Charles, you have demonstrated that "you are not a robot" - no damage anyway.
K2
K2
Building a twin cylinder inline i.c. engine.
- Thread starter Brian Rupnow
- Start date
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danallen
Well-Known Member
I agree that making the crankcase from a single solid block is the best way to go.
Probably drill and bore one of the big holes first, then move over to do the second big hole, then do the four corners on the milling machine.
oldengineguy
Well-Known Member
Brian: FWIW I made a crankcase for Doug Kelleys Nash 25 engine from 12 pieces of 3/16 cold rolled 1018 steel bolted together then J B Weld caulked the seams from the inside to seal it up. It's not a finished engine yet but the 'case has held up perfectly through numerous drill/ tap and bore operations. Cheaper than a big block of steel or aluminum.
Colin
Colin
And so, it begins. Today I bought a piece of aluminum 3" x 3" x 4 1/4", brought it home, and machined it to finished size. Tomorrow I will set it up in the four jaw chuck and start to hollow out the cavity in it. In the background you can see the engine I built ten or twelve years ago, which was based on the Jaguar engine by Malcolm Stride. Basically, it is half of the Bobcat which I am building now.
Tomorrow will be an exciting day---
Brian, I think it will be a bit boring
Cheers
Andrew
Cheers
Andrew
It is 1:30 o'clock here and I just finished the cavity in the crankcase for my inline engine. I started at 7:00 this morning and took half an hour out for breakfast when wife got up. Looks like a total of 6 hours to machine that cavity. I doubt very much that it would have been quicker if it was made out of five plates bolted together. The cavity was machined in the same sequence that I showed in an earlier post.--One big hole, not interrupted cut, one other big hole, very interrupted cut, four corner holes--interrupted cuts, then a pass around the inside of the cavity to clean things up.
I just talked to my cast iron suppliers, and they want $40 for a piece of round cast iron 2" diameter x 4 1/2"long. That would be enough to make my two cylinders, but man, that price just kills me. Aluminum cylinders don't work well, they constantly shed a sludge made up of lubricant and the inside of the aluminum cylinder wearing away. I normally make my cylinders from cast iron, but with the price of cast iron, I'm looking for a cheaper alternative. I've been wondering about a cold rolled steel cylinder running with a cast iron piston and Viton o-ring. Any advice would be a good thing, but don't tell me unless you've done it yourself please.
A different supplier just gave me a price of $44 for the same thing.
Brian,
That is expensive, just checked my supplier, a meter(39") of 55mm(2.16") dia is AU$96. They know how to get at you.
Cheers
Andrew
That is expensive, just checked my supplier, a meter(39") of 55mm(2.16") dia is AU$96. They know how to get at you.
Cheers
Andrew
Alloy fins and piston with cast iron liner as per original, viton ring. Or steel fins with iron liner, alloy piston and Viton ring
radial1951
Well-Known Member
Hi Brian, would you mind saying where you got that quote? Is it continuous cast rod? That is quite cheap compared to the quote Brian R received. Only AU$96 (CAD87) and it's 9 times as long at 1m (39.37") and 4mm bigger in dia. I guess that's the advantage of buying 39" vs 4.5". I'm in NSW too, so would be handy to know where to get C.I. rod.
Thanks, Ross.
Ross,
Get it from Edcon Steel, in Sydney, They cut to length. https://www.edconsteel.com.au/
Cheers
Andrew
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Wow. I though materials here were expensive. I recently bought maleable cast bar @ 3.3CAD per Kg
Have you considered large vehicle (truck) drum-brake cylinders from a scrapyard? - They are cheap and high quality cast iron. (My Dad used them to make steam engine cylinders). Small ones are getting rare as Disc Brakes are cheaper for cars so fewer drum brakes around.
K2
K2
250mm of 50mm dia EN8B round bar £32 in UK. (includes "Free" delivery).
K2
K2
danallen
Well-Known Member
So about $40 US for 10" of 2" diameter delivered. Sounds about the same as our cost.
Bits and pieces, pieces and bits. I just finished the cylinders, except for about a million holes yet to be drilled. About the cylinders--I called Barrie Welding and was quoted $40 over the phone for 4 1/2" of 2" diameter cast iron. I went down to pick it up, and they wanted $50. Of course I said that I was quoted $40 over the phone. --And the guy said---"Oh yeah, but there is a $10 cutting charge". I paid, but I don't think I will be buying any more material from them.
A wise old fish once told me "the more fins the better!!!", so I added fins to the very plain looking cylinder heads. I like it!!
