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Unread postPosted: Tue Aug 01, 2006 5:34 pm
Author: Mihlrad
right.... which makes your piston... like...2 dollars or less....

Unread postPosted: Tue Aug 01, 2006 8:00 pm
Author: Velocity
PVC type II rod is possibly the best piston material. It offers high impact strength and tensile strength (which are important), and is sold at a little under a dollar per inch (about $11 for 2" PVC type II rod)

noname, what do you mean when you say the piston can hold over 300 PSI? Why would it need to?

EDIT: when can we expect pictures? I know your building it now, but I just need a rough estimate

Unread postPosted: Wed Aug 02, 2006 7:12 am
Author: mark.f
I'd feel more comfortable buying a piston from rmich732 than noname. He's actually made a few nice pistons already.

Unread postPosted: Wed Aug 02, 2006 8:16 am
Author: Mihlrad
I still dont understand how it costs 20 dollars in parts to make a valve.

Unread postPosted: Wed Aug 02, 2006 9:52 am
Author: noname
2" rod is probably good, but I don't have a lathe. It makes things considerably harder to do. And making o-ring grooves in solid Delrin is very hard and I've only cut one so far, which is too deep. Expect pics by next week at the latest. I could put it together without glue or screws first though.

Unread postPosted: Wed Aug 02, 2006 10:12 am
Author: beebs111
since i dont have a lathe, i am looking for someone to machine me a pretty nice 3" piston for a coaxial, with a 1.5" sealing face. pm me with pricing and details and such. i have tried a few different pistons and they are not working very well. thanks alot :D !

Unread postPosted: Wed Aug 02, 2006 11:15 am
Author: Velocity
noname: put up a picture before it is all glued together. Its been weeks since you posted this thread, and everyone cannot answer your question (Would people buy valves) without seeing them first!

Markfh11q: Thanks man :P

Unread postPosted: Wed Aug 02, 2006 4:18 pm
Author: Mihlrad

How can you make O-ring grooves and shape delrin without a lathe? It wont be made to perfection?

Unread postPosted: Wed Aug 02, 2006 4:19 pm
Author: Shrimphead
O-rings aren't nessecary on all valves.

Unread postPosted: Wed Aug 02, 2006 5:49 pm
Author: Velocity
he said that this was a chamber sealing valve... so I am pretty sure that orings ARE necessary... could be wrong though

Unread postPosted: Wed Aug 02, 2006 5:58 pm
Author: Mihlrad is he shaping delrin and cutting perfect grooves without a lathe....

Unread postPosted: Wed Aug 02, 2006 6:21 pm
Author: M3NT4L
Its possible with a dremel. Milhrad do you know what a dremel is, if you dont please google it. :roll:

Unread postPosted: Wed Aug 02, 2006 6:32 pm
Author: huse_spud
if we are on the topic of valves here's my question.

on a coaxial barrel sealing type gun how far away does the piston need to come back from the barrel to get as much air flow as possible?

Unread postPosted: Wed Aug 02, 2006 6:38 pm
Author: beebs111
i gave my mini 1 1/2" chamber 1/2" barrel 2" to fly back. unfortunatley i didnt use a spring and the piston flew through the back of my threaded cap

Unread postPosted: Wed Aug 02, 2006 6:51 pm
Author: CS
I belive he knows what one is. Its the fact that he is using such a innacurate tool for something that requires you to be presice. Its like cutting butter with a chainsaw down to .001", it is simply not going to be as nice as if you were to use a tool designed for the job. If I recall right BLB stated that 5-10% squeeze is ideal for a sliding seal for a oring. Lets say your using a .125" thick oring. If I figured this right that means that each percentage of squeeze is tolerant to .00125". The cross-feed on a 8x12 HF lathe is only accurate down to .002"!!! With a dremel I couldnt see anyone even touching .01". Even at that your allowing your squeeze to deviate around 8% while being that precise.

Morale of the story being that a dremel is WAY to inaccurate for the job. Either your going to end up with leaks, or compensating with a higher squeeze lessing performance and most likely still having leaks. Do I need to further discuss this?!