Machinist in America?

Lockednloaded · Sun Jul 31, 2011 12:44 pm

Is there a machinist (not necessarily a pro) who can machine a 3/4" o-ringed piston to be used in a piston hybrid? I can pay cash, possibly send the 3/4" stock, and I can send measurements down to a hundredth of a mm. I'm out of options machining a good one myself, for I don't have a drill press or a lathe

Gun Freak · Sun Jul 31, 2011 12:48 pm

Seeing all the things you build... you should buy a lathe

I'm looking for a cheap wood lathe that I can mess around with.

Lockednloaded · Sun Jul 31, 2011 12:52 pm

Gun Freak wrote:Seeing all the things you build... you should buy a lathe
I'm looking for a cheap wood lathe that I can mess around with.

All my funds have been abruptly diverted to a car, so a lathe is out of my reach for the time being

I also don't think I could use a lathe enough to "make it pay for itself"

Technician1002 · Sun Jul 31, 2011 1:19 pm

A small drill press can be had for less than the price of a couple tanks of gas. I got mine new for less than $50 when I needed to make a piston. I had an assigned budget for the project to make the contest fair. I was well within the budget.

Edit, just checked their website.. They are sadly no longer under $50.

Sadly over $30 more then when I bought mine. Sale: $69.99

Lockednloaded · Sun Jul 31, 2011 1:25 pm

I have a "dremel press" that I've tried to do it on, but its far too small. It's not only a money issue, but also a space issue, and an issue that my parents don't want me to spend anymore money on guns for a while, and it would be hard to cover up the purchase of a drillpress with "of that old thing, we've had it for months"

Willdebeers · Sun Jul 31, 2011 1:34 pm

I have a lathe, but live in the UK. :/

I could do it but it would depend how big it is.

Lockednloaded · Sun Jul 31, 2011 1:38 pm

Also will, I would like to pay in cash and I only have American dollars. It would be about 3/4" x 2-1/2"

Willdebeers · Sun Jul 31, 2011 1:41 pm

Lockednloaded wrote:Also will, I would like to pay in cash and I only have American dollars. It would be about 3/4" x 2-1/2"

Thats fine.

If I do this, I must insist having the pipe/fitting that it would slide in. We do metric here, so I would be unable to get it myself.

And Cash? Why would I want to be paid for something I love doing?

Lockednloaded · Sun Jul 31, 2011 1:44 pm

Of course, I also have a digital metric caliper, and I would also send you the orings that I have

EDIT: just saw your small text, the cash would be to cover shipping, why pay todo something you love

cannon monkey · Sun Jul 31, 2011 1:45 pm

im here in FL and thinking bout buying a cheaper metal lathe coming here in the next following months for only 350-400 i dont see why not buy and try it

Willdebeers · Sun Jul 31, 2011 1:47 pm

Lockednloaded wrote:Of course, I also have a digital metric caliper, and I would also send you the orings that I have

Would you want them floating?

I have a big box of O-Rings but could not necessarily guarantee that I have one that fits. You're right, it would probably be better if you sent them.

I also have a choice of materials to work with, from Nylon to Steel.

Lockednloaded · Sun Jul 31, 2011 1:52 pm

Willdebeers wrote:
Lockednloaded wrote:Of course, I also have a digital metric caliper, and I would also send you the orings that I have

Would you want them floating?

I have a big box of O-Rings but could not necessarily guarantee that I have one that fits. You're right, it would probably be better if you sent them.

I also have a choice of materials to work with, from Nylon to Steel.

Well friction is not much of an issue because this isn't a QDV, but if floating is the better option, then that's what I would like. I may have some hybrid builders chime in about the ideal piston material, so I'll have to figure that out. It would have to be impact and heat resistant and mildly light-wieght so that it can survive

ramses · Sun Jul 31, 2011 1:53 pm

I could do it. I would also suggest you ship them the pipe it will slide in so they can bore it out and make it nice and smooth.

You may also need to lap the piston seat (barrel part) to the piston in case the tee threads are not exactly straight.

Willdebeers · Sun Jul 31, 2011 1:58 pm

Lockednloaded wrote:
Willdebeers wrote:
Lockednloaded wrote:Of course, I also have a digital metric caliper, and I would also send you the orings that I have

Would you want them floating?

I have a big box of O-Rings but could not necessarily guarantee that I have one that fits. You're right, it would probably be better if you sent them.

I also have a choice of materials to work with, from Nylon to Steel.
Well friction is not much of an issue because this isn't a QDV, but if floating is the better option, then that's what I would like. I may have some hybrid builders chime in about the ideal piston material, so I'll have to figure that out. It would have to be impact and heat resistant and mildly light-wieght so that it can survive

What mix # would you plan going up to?

If you want lightweight but heat resistant, then aluminium is probably best for you. But i'm no expert, so take my advice with a pinch of salt.

Lockednloaded · Sun Jul 31, 2011 2:03 pm

I doubt I'll ever go over ~ 10x, but all the parts on my gun can handle 20x so I'd likethe piston to handle that as well. I don't know if you've seen my valve, but there will always be an air cushion and a thick rubber washer to cushion the piston force