LPR questions. MAchine work guys help!

[Chris TS-1438]

alright. I need to know if I am out of line with one of my projects. I wont post the pictures yet...but I will ask a few questions that may provide a fair allusion to what I am doing...

1. What are the tolerances on most LPRs? What I am asking is, could a person take the guts out of (just for examples sake, a palmers lpr) an LPR, could the put it in a solid block of aluminum and expect the same function?

2. what material are most LPRs made of...think higher end...palmers, AKA, anything like that.?


3.Could the outside of an LPR be tapped with a threading die in order to be screwed into an aluminum block?


all you Airsmiths, help a brother out. If I get enough response I will post my idea/design sketch(s).

[knownothingmags]

trying to make an lpr forgrip or a version of that?

alot of what you are askinging is duable.

ask luke, he is my go to right now, if not him XMT

hope it helps,

[Chris TS-1438]

yeah. something like that. Oh BTW knownothing, I figure my battery and emag issues out.

power adapter was 9v instead of 12v. and emag was missing quad oring. Thanks for your help!

[renie]

the one i sketched up for hill would work but i just havent had the time to machine one

[Spider-TW]

The two critical parts are maintaining the wall thickness for the pressures you're using and getting the bore smooth and within a few thousandths of your o-ring size for the piston. You can modify the piston a little to make up for ano or bore polishing. A reamer for your bore size is a good start.

As long as you keep the seat seal separate, the tolerances on it and the pin aren't too bad.

I would start with the dimensions on a micro-rock and add threads where needed and adjust for the available tooling. Or, take a rock/micro and make adapters for it.

[Chris TS-1438]

i would like to find out the wall thickness of a micro rock and the tap a hole to put it in and use a die to thread the outside of the micro-rock. so it could be screwed in and out, I guess it could be a slide in type setup without much consequence.

[Chris TS-1438]

here is a rough example of what i have been toying with.

no time at the end of the semester to do legit renders...may be in may i will get to it...





they are pretty rough. but the general idea is there.

[Spider-TW]

here is a rough example of what i have been toying with.

no time at the end of the semester to do legit renders...may be in may i will get to it...





they are pretty rough. but the general idea is there.

I think that was very close to renie's setup. The real meat to the whole thing imo, is the porting and the HPR 'bypass'. There's some drilling and plugging to do there. Typical pneumag problem - mounting and routing the LPR. A concentric arrangement probably wouldn't help either.

[hill160881]

I would love to see someone make one of these. I will be trying to do one myself if I ever finish my car build.

Here is the one renie came up with in our thread discussing this very topic. mayb this will help spark an idea.



Pic

[Spider-TW]

^^^ just looking at the scale there, Hill, I would think that piston diameter is a bit small. I think what makes the rocks better at higher input pressures is their larger piston to port diameter ratio. Schrader valves are pretty small, so it might be fine, but you might want to look at that before you start cutting.

[hill160881]

You don't think the larger piston diameter is only important for lower input pressure applications? That's what I was thinking.

[renie]

Did u ever hook up that tiny prototype lpr I sent u hill?

[hill160881]

Yes but I have not had time to really punish it yet. Only a function test. I will put some time into this soon. My car is on the home stretch. Just some things to finish up and the interior to redo.

[Spider-TW]

You don't think the larger piston diameter is only important for lower input pressure applications? That's what I was thinking.

The piston is on the output side, so that area goes to the output pressure versus the force from the seat and the input pressure. At least that's what I'm thinking atm.

[hill160881]

Very true but we only need 100 psi output from the LPR. The micro rock needs 300+ with only 400 input. Basically the range of input vs output was larger for the micro rock. This was my reasoning but I have yet to sit down and do some math.

For the mag the 800+ psi input is so far over the 100 psi output needed that I thought we could get away with a smaller ram. Or I may have it backwards..... Probally.