McMaster Carr Belleville washer problems?

[RMM]

Has anyone had any problems with McMaster Carr Belleville washers galling their Ninja regulator piston?McMaster Carr calls for a min washer I.D. of .317 and a max .625 http://www.mcmaster.com/#9713k66/=tcktmx so I believe my problem lies in my washers O.D. @ .609 and the I.D. @ .330 with the piston @ .309 and the regulator washer cavity @ .636,  Not knowing how to figure the O.D. of the washer when squished what I see is I have more room for the washer O.D. to move in the regulator washer cavity than the washer I.D. around the piston which means the washer I.D. has a few thousandths to contact the piston.  Before I open up the washer I.D., knowing that will change the dynamics of the spring action, I thought I'd petition the forum. 

While I'm at it I should ask if my Ninja regulator piston is ruined with the galling?

Thanks in advance

[rsterne]

Did you use some Silicone grease to lightly lubricate the washers and the piston before installing?.... Metal to metal dry contact is never a good idea.... If the galling is minimal it probably won't make any difference, bad enough it may cause a consistency problem in the output pressure.... I wouldn't modify the Bellevilles....

Bob

[RMM]

Did you use some Silicone grease to lightly lubricate the washers and the piston before installing?.... Metal to metal dry contact is never a good idea.... If the galling is minimal it probably won't make any difference, bad enough it may cause a consistency problem in the output pressure.... I wouldn't modify the Bellevilles....

Bob

No I did not apply silicone grease to the washers and piston, do you think this may be the problem.     Thanks for that important tidbit Bob.   And yes the galling is minimal and cleanup would not be a problem other than removing the anodize coating.  By the way this regulator is  my 1.5K FDPCP fill bottle, I found it empty and tried to refill but heard air from the 1.8K burst disc thus the tear down and inspection.   

[Motorhead]

Doing a quick pass with a small stone down the I.D. bore of bevels to take out any stamping flash don't see hurting a thing.

[rsterne]

I agree.... Some guys polish both edges with 600 grit paper as well....

Bob

[RMM]

Thanks gents and I did polish the I.D. of the the Bellevilles and polished out the dings (galling) on the piston stem, greased the washers stem and o-rings and she blew a 1.8k burst disc @ roughly 1.4K and there's new dings in the piston stem.  I'm still thinking I've got a bad batch of Bellevilles so if you gentlemen have some McMC Bellevilles sitting around could you dimension them for me please.  As a matter of fact if you have any Ninja Bellevilles would you dimension them for comparison also? 

Thanks for the help you've already given.

[Motorhead]

Sadly .. NINJA will not !!! sell There OEM Bevel washers as replacement parts.

[Rescue912]

I've had the 1.8K discs blow at under 1500PSI before so may not be the regulator.

[RMM]

It's the gouges (I think this is the right word) to the piston stem that is the give away to interference from the I.D. of the Bellevilles.  Do I have a bad batch of non OEM 1.8K burst discs also, very well could be but the first burst disc to blow was a Ninja so this is got me going hmmmmmm. I ordered some Ninja 1.8K burst discs last night.  Still pondering a solution here in Illinois as I'm going to figure this out, with your help of course, and get my FDPCP fill bottle back up and running. 

[RMM]

Well I've found out that the Ninja Belleville's are .625 O.D. with .318 I.D. which tells me my McMC washers are not within spec for my Ninja regulator.  Using the dimensions of the McMC washers I have .0135 lateral movement with the O.D. and only .0105 lateral movement with the I.D. which means I should have more I.D. lateral movement than the O.D., e.g. Contact. 

Other than McMC does anyone have a source for correct dimension Bellville's? 

[Motorhead]

Well I've found out that the Ninja Belleville's are .625 O.D. with .318 I.D. which tells me my McMC washers are not within spec for my Ninja regulator.  Using the dimensions of the McMC washers I have .0135 lateral movement with the O.D. and only .0105 lateral movement with the I.D. which means I should have more I.D. lateral movement than the O.D., e.g. Contact. 

Other than McMC does anyone have a source for correct dimension Bellville's? 

SEND IN your Regulator to NINJA ... pay them for the service and correct parts would be my suggestion at this juncture   

[RMM]

Here's what I've come up with.  My McMC washers are way out of spec not only in their I.D. and O.D, they're .030 thick and anywhere from .051 to.056. So I did a Google search for a higher quality Belleville spring disc source and found one with a possibility based upon their overall great service and high quality products so I ordered Zoro  http://www.zoro.com/i/G0908275/?category=7612 . They came as .609 O.D., .327 I.D., .048 H, and .032 thick, radiused corners and in general a higher quality spring. Delighted with these disc springs and having removed the chatter marks from the reg piston, included a thorough reg etal,  I installed 12 Zoro spring discs ))()()()()(( then filled to 1.8K and achieved aprox 1.3K reg pressure with no burst disc failure.  For the shim change I rapidly released the bottled air, disassembled reg, added .010 shim, refilled to approx 1.4K(?) then BANG!! The Ninja 1.8K burst disc blew!

WHAT??!!
 
I disassembled the reg to find fresh chatter marks on the piston then I had a Eureka moment!!!  I might be letting the air out of the bottle to fast and the disc springs were chattering thus moving out of alignment and the disc center rims were leaving chatter marks on the piston stem which were impinging proper piston movement. HMMMMM???   I cleaned the piston, installed the spring discs with a .010 shim, added a new Ninja 1.8K burst disc, refilled to 2K and in return I achieved 1.4K reg pressure and no burst disc failure.  I slowly let the air out of the bottle, disassembled the reg, saw the stem wasn’t damaged, installed an additional .010, and refilled bottle to 2K, reg pressure at 1.550K and no burst disc failure.  I slowly let the air out again, refilled to 2K, reg pressure at 1.550K with no burst disc failure so I did the empty and refill process again and again with no burst disc failure.  [b}By jove I think I‘ve got it!!!!![/b]

Two things learned is;
(a) I found high quality Belleville spring discs at a better price through Zoro   
(b) Don’t let your air out to fast. 

[rsterne]

I am wondering if your gauge is reading low.... I have had one 1.8K disc fail at 1500 psi and a few at 1600, most seem to hold 1600 in field conditions without issue.... However, it is not common for relatively good gauges to vary 100 psi, and the small gauges that come on a regulator are junk.... and hard to read to boot.... I use a gauge with 100 psi graduations (easy to read to 50 psi) for setting up regs, one that I have checked against a couple of others....

Bob

[RMM]

I'm actually using 3 - McMC liquid filled gauges http://www.mcmaster.com/#3845k1/=tgswxw  with a mid range accuracy within +- 1% that I have checked against each other.  BUT! I have a McMC gauge on the Benji pump and the Benji pump gauge on my reg checker bedcause the Benji gauge is right on the money @ 1.5K with the McMC. 

All I can do now is chalk this one up to experience and I don't want to experience it again.  Lessons learned.   

[nervoustrigger]

For what it's worth, over the last few weeks I've had two 1.8k burst disks rupture on me using a regulator setpoint of 1.5k.  One Ninja burst disk and another generic one.  In both cases, it happened at room temperature...meaning the volume of air had not been warmed up by taking the rifle outside in the sun such that the plenum pressure would have climbed significantly above the reg setpoint.

Like you, I am using a liquid-filled gauge rated for 1% mid-range.

Not real happy with 1.8k burst disks right now.