Super Newbie - Elbow Engine UHMW, HDPE.

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Looks like they tunred out well Ian. Still following along.

Bill
 
Interesting build you have going here, keep the pics coming.
Brock
 
Found another plastic store with better pricing; 2" for $9.30/foot. THey dont have 2 1/2", so the next size up is 3" and that's $24.90/foot <--- *bang*

Here's what it will look like with only using 2" rod; should work fine enough.

2 1/2" Rod 2" Rod
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Used chop saw to cut out the valve blocks and cylinder blocks:

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I got to excited that i can finally cutting the 2" bar, that i forgot that i wanted to wait to separate the cylinder bar into two, but i know of a way to keep them lined up.
 
Peck drilled out some of the valve, then used a box cutter (xacto knife) to cut out the rest of the shape. Counter sunk the bolts mounting the valve block to the base.

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Penny for scale.

What it'll look like with the cylinder blocks:

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As you can see, i have not drilled them out...yet.
 
Drilled out Cylinder blocks at 25/64". The pistons are 3/8" (24/64") so that gives me 1/64" of forgiveness.

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PISTONS FIT AND SLIDE NICELY!!!!!

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I'll have to shorten some of the pistons since they hit the valve block. Check previous screenshots.

Almost finished!!!
 
:'( It's a sad, sad day. The pistons worked when they weren't bound to the axles, but when i mount the cylinders to the base, the whole thing jams up. :'( Too many inaccuracies, since i dont have a lathe yet. I sprayed some WD-40 but it didnt help much. I'll see what i can do to find out what the worst part is and do what i can to fix that.
 
Well, the fact that it doesn't run right away is nothing new to the members of this forum,,,we've all been there..

Don't give up yet....keep at it.

What's binding specifically? Can you isolate it?

Dave
 
Okay so i remeasured the pistons lengths and it turns out they're around 1/8" too long. It's because the elbows must have not been pushed far enough into the pistons. I just cut them down to the proper length, will be testing some more.

EDIT: Okay, it improved, but it is still pretty stiff, will check square-ness of elbows/pistons. A bit of sanding to square up the bottom of one of the cylinder blocks, and it should rotate better.
 
Ah NOW

If your going to sand, put the paper on a flat steel block. You'll get flatter surfaces that way.
BE PATIENT! you want to take small amounts of materail off and maintain a good surface finish while you do it

Dave
 
Hi all. My second post here in HMEM. Nice build. Did the OP ever finish this build?
 
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