SpudFiles

Your machinist should be familiar with it. It's basically a pipe without a seam. Some varietys are used to make things like hydraulic cylinders...these tubes have a precision bore.

Can be heavy, but you're not building a "light weight" anyway.

Oh lord... we've been over this SOOOO many times before. Don't worry about a lighter piston versus a heavier piston's bumper requirements. Just remember that a lighter piston opens faster and therefore offers better performance.

I went today to machine shop and had him make it to same specs as JSR had in his pic. Hoping they get it done today so I can put it together this weekend. Will keep you guys up to date.

Its your baby now JSR. You bought it!

I feel somehow responsible for this launchers' success now did you give them the chamber pipe so they can get as close a tolerance as possible?

You should JSR , you have helped me a lot design this thing. I did take chamber pipe to shop yesterday and they did a great job. I just got done cutting 1/2" neoprene for piston and also for the bumper. Just JB welded them into place and put clamps on. Gonna let em sit until Sunday, then take em to shop on Monday to have it welded together. Gettin' there. Will take some pics of piston once I can unclamp it.

Jb welded rubber sealing face to the piston?? Bad idea... Why didn't you bolt it?

I did both, bolted it into piston which I had tapped and also put a 1.5" washer on it. Figured both would give a great fit.

Well then.

I beg your pardon :tongue3:

All good man, my bad, I should have mentioned that.

Can't wait to see this thing done!!

Any suggestions on type of valve I should use to fill the chamber? I have a 3/4" elbow. Is a schrader(sp?) the best? Will need to to be able toehold 400 psi.

I would just put a tee behind the piston with a schrader on one port and the pilot on the other. That way the pilot volume is kept to a minimum.

Looking forward to seeing it

In my experience an ordinary schrader valve is good for at least 850 psi.