SpudFiles

It's not so much that I'm worried they will know what it's for. How much would you guys expect an aluminium piston with o-ring grooves with decent tolerances, M10 female threads at either end and some design modifications to reduce weight would cost?

Well the advantage of having it how it is now is that it finally holds in place under pressure as it should. For an unknown reason (I think Fnord offered an explanation about the sealing face), the valve would open prematurely if I put something like 100PSI in the pilot and 100PSI in the chamber when it probably shouldn't open until the chamber reached ~120PSI.

MrCrowley wrote:It's not so much that I'm worried they will know what it's for. How much would you guys expect an aluminium piston with o-ring grooves with decent tolerances, M10 female threads at either end and some design modifications to reduce weight would cost?

Mods move this to the Machinist thread please?



What diameter?

Let's not get ahead of ourselves here

Diameter is ~50mm. I assume aluminium would be the most suitable material in terms of weight, strength and cost. I assume I would also have to get an idea of what type of aluminium stock I should ask for.

MrCrowley wrote:Let's not get ahead of ourselves here

Doesn't cost you much to post a quick drawing and see what the forum machinists will do it for. I'll have to pass a priori, too big for my little machine to make comfortably.

Don't think I would outsource to forum members mainly because the postage will set me back more than I can probably get it done locally.

http://www.cams.net.nz/



They will chuckle at you.

Yeah, looks like they would be expensive. I was thinking the first place I would try is where I get my welding done as they're reasonably priced but I'm not sure if they would bother with something like this as it's probably a hassle for them to do (changing the lathe setups?).

Anyway, I just need a guesstimate price quote because I don't want to spend much money when I have a working piston as it is and pneumatic cylinders can be had for cheap.

250-500 gram package from Melbourn would be $15, make a diagram and i might be able to do it on a weekend at work.

Does anyone know if 1/2" cpvc fits snugly in 3/4" cpvc? I'd like to use it as a bolt, but I'm not sure if it'd be a tight enough fit

Crna Legija wrote:250-500 gram package from Melbourn would be $15, make a diagram and i might be able to do it on a weekend at work.

Thanks for the offer. How much would the cost be for materials and time?

I'll see if I can get a diagram up today but I'm bogged down with stuff so we'll have to see.

Lockednloaded wrote:Does anyone know if 1/2" cpvc fits snugly in 3/4" cpvc? I'd like to use it as a bolt, but I'm not sure if it'd be a tight enough fit

1/2 cpvc o.d = .840

3/4 cpvc i.d = .804 (sch 40)
3/4 cpvc i.d = .722 (sch 80)

I've found thisand it has different numbers, weird..

Here's my link:
http://www.harvel.com/technical-support ... /cpvc-pipe

those numbers seem to be a little off by my experience. I've been able to fit 3/4" CPVC into 1" CPVC in the past. A side note on that, has anyone who has bought CPVC lately noticed the 1" pipe isn't very round on the inside anymore?

MrCrowley wrote:

Crna Legija wrote:250-500 gram package from Melbourn would be $15, make a diagram and i might be able to do it on a weekend at work.

Thanks for the offer. How much would the cost be for materials and time?

I'll see if I can get a diagram up today but I'm bogged down with stuff so we'll have to see.

Depend if were lucky and I find a peace i could use at work free, if not under $50 for sure. Free for the time since ill be at work anyway lol , since it alu wont take long to machine on a big lathe.