A dumb question about that Star pneumatic thing-a-ma-bob??

[Russel Nash]

Howdy all,

Yeah, I have yet to really cast boolits and then to size them and lube them.

I read up on this forum on what stuff to buy first, and went with you all's recommendation on the Star.

In one thread I started I specifically asked about what doo-dads to get with it.

So I got the shovel handle and the pneumatic whatch-ya-ma-call-it.

I also got the heater.

Sorry, I don't mean to get too technical here with my jargon. :wink:

So anyway, I was kinda fiddling around with the Star tonight, kinda half way putting things together (thinking to myself that for what it is and its size, they sure do want a purdy penny for it... Hmmn.... I wonder if I could make one of my own? Hmmn...).

So I started thinking... yeah, dangerous, I know... if I am going to concoct some sort of lube and most likely gonna be using the heater to turn it back into some liquid-ey like state, why the heck do I need the pneumatic ram???

Could I just buy a quick disconnect air hose fitting, see if it fits that cap, and just pressurize the whole reservoir?

I'm sure I can't be the first one to ever suggest this, right?

Heck, just kicking around some ideas now, a person could theoretically outfit the thing with a valve stem like what's used on a car's tire and take a hand pump like for bike tires and basketballs to pressurize it.

All this talk about lube reminds me I got another question... I guess I will poke around the whole forum for a bit to see if I can find a thread on it already.

If I can't find it, I'll be back starting another thread....

Thanks in advance....

[xr650]

The problems I can think of:

The threads in the cap are straight. The threads on air fittings are tapered and different pitch.

The cap has no seal to tube.

Then there is that pesky weep hole in the tube.

[Russel Nash]

Yeah, I noticed the weep hole in the side, too.

Hmmn..???


Ya know if there is enough meat there on a coupler, I could always chuck that in a lathe, take some metal off and recut some standard size threads, like 3/8" X 16.

I don't have one of my nail guns handy so I can't necessarily refresh my memory on what threads those things do have.

And as far as the seal, I think I could probably find either a rubber O-ring big enough to fit the underside of the cap, or I could just wrap the threads in plumber's teflon tape.

The weep hole?? Isn't that what they make wire welders for....??;)

If that's too permanent for ya, I guess a teeney-tiny little set screw might seal that off.

I'm just a newbie, so what do I know.... I'm just looking at things with a fresh set of eyes, not necessarily encumbered by paradigms.

And I'm not afraid to try to think outside of the box and ask questions either.

[WildmanJack]

Russ,
Unles yo are going to attach an air reservoir to the pneumatic tube, you'll be refilling it pretty regularly. The tube isn't big enough to hold a large amount of air so you need to keep it connected to some type of reservoir. I've cast 400-500 rounds and never had my compressor kick on, and I have a little bitty tank on the compressor, probably like 2 1/2 gallons. But I'll tell u this. I doubt I'll ever go back to manually pressurizing that thing again. With the pneumatic tube that's one less thing I have to worry about . I just keep on sizin'...
All the best,
Jack

[runfiverun]

the lube reservoir is for lube.
the air cylinder puts nonstop pressure on the lube that you would have to do by hand otherwise.
probably okay untill you use the boolit feeder.

[xr650]

Russel,
Seeings as how you have access to machine tools.

Make a new top cap with an o-ring fit in the cap and drill and tap for 1/4" NPT (This is what your nail gun has). You may want to make the OD of the cap larger, the air pressure is going to push on them fine threads. You don't want the cap swelling and letting loose.

If I remember correctly the lube piston is drilled thru, so you may need to make a new piston. I would put two o-ring grooves to seal better against the air pressure.

Simple fix for the weep hole would be to drill and tap 1/16" NPT if the wall is thick enough (I don't think it is). When you weld it remember all it takes is one pin hole to let a lot of air out. [smilie=1:

You notice how all the threads are tapered to seal pressure. Straight threads won't hold pressure with out an additional seal.

Or you could use the air cylinder that you bought and forget about this post. :mrgreen: