LP10 piston assy assembly help

[seamaster]

My LP10 shooting pressure is very low.

Air cylinder is holding pressure well.

Pallet can't make it out of the barrel.

http://www.steyr-sport.com/images/flipb ... 0_c_en.pdf

Problem is the piston assy section 29 and valve assy section 18 on the diagram

Need help to put this humpty dumpty together after cleaning it.

Specific technical question:

I was very careful when I dissemble section 29. I did not see 29.13 and 29.7 in there.

Are those two parts essential?

What is the tightening pressure relationship between 29.5 and 29.4?

Too tight, no air goes in. Too loose, pressure destroys 29.9 seal.

Much obliged for your insight into the problem.

[seamaster]

I took the regulator apart.

I can understand the basic function, the flow, how air pressure is progressively reduced by resistance.

But there is one part I don't understand. There are 8 washers stacked together on the outside of air flow tunnel.

What are those washers for? They don't seem to be in the direct way of air flow, so how are they involved in reducing pressure?

[j-team]

I took the regulator apart.

But there is one part I don't understand. There are 8 washers stacked together on the outside of air flow tunnel.

What are those washers for? They don't seem to be in the direct way of air flow, so how are they involved in reducing pressure?

Those are Bellevue washers which are not flat and they are stacked in an alternating sequence and are in fact a spring. The strength of this spring along with the size difference of the high and low pressure pistons (each end of 29.1) is what determines the pressure reduction.

No offence, but if you don't understand this or how a regulator works, you should take it to someone that does so it can be reassembled properly.

[seamaster]

You are correct. I have no business taking the regulator apart not knowing the intricacy of those tiny things.

Your explanation of "Belleville washers" is excellent. I have looked at multiple diagrams of PCP air gun drawing. Those washers are drawn as a spring. I could not understand why washers would be drawn as a spring. Now I understand those are no ordinary flat washers that stack together. Why they are very slightly curved.

Someone must have explain those things to you as you took your first regulator apart.


https://www.youtube.com/watch?v=0isHchgWT8U Good explanation on those washers. Now I understand why those washers are used; to keep chamber volume identical as air cylinder bottle is screw on the regulator.

[SamEEE]

https://www.youtube.com/watch?v=0isHchgWT8U Good explanation on those washers. Now I understand why those washers are used; to keep chamber volume identical as air cylinder bottle is screw on the regulator.

Thanks for the link; nicely explained video. Mad for taking the regulator to bits, but I suppose this is how we learn!

[scausi]

You should not have disassembled 29 , all you had to do to remove that intact ,was leave the screws with the red paint alone .
And only unscrew the others, This would have allowed you to remove in one piece and get access to remove plunger 18 and replace .
Me, thinks you may need to send to Pilks to be put back together, the bevel washers need to go in a certain order.

[dronning]

The washers go together like this ()()()()()(), so they compress together.

- Dave

[seamaster]

Is it )()()()( or ()()()() ?

wide base or narrow base end ? Common sense says wide base.

[dronning]

Is it )()()()( or ()()()() ?

wide base or narrow base end ? Common sense says wide base.

It really wouldn't matter the tension would be the same. The large end out doesn't give any more stability. I would look for wear marks and put it back the same way.

- Dave

[seamaster]

http://www.steyr-sport.com/images/flipb ... 0_c_en.pdf

That Steyr diagram is excellent. Those washer drawings are not for show. Look at the edge width, they are alternating. Once you blow up the drawing to max. It actually showed the orientation of the washers. ()()()()

Those darn engineers. They are good.