Powermax 45 Retaining cap problem

[SeanP]

Seem to be getting through a few retaining caps (genuine hypertherm), on my third now and only the second shield.
Would it be water splashing back up and sitting in the gap between the cap/shield that causes them to break down?

I even got a bit of a shock the other day when I touched the shield tapping away a slag pile, I ran the multimeter from the plate to the shield and it read 68volts, I wonder if this can effect cut quality?

[jimcolt]

Can you show a picture of the way your torch is mounted on your machine? It looks like your are either clamping by the retaining cap......or clamping on the sleeve, very close to the retaining cap. There is no reason to read any voltage on the shield...the shield is electrically isolated, mounted on the composite threads on the retaining cap. If you have a damaged cap...and for some reason the shield and nozzle were shorted together....then it could be possible to read some stray voltage on the shield I suppose.



Jim Colt Hypertherm

[SeanP]

Wow that was quick Jim, thanks.

I seemed to notice the break down on the cap after cutting a good bit of 12mm steel, not sure if the water hanging around the gap isn't making it happen.

I did try a modification on a shield to see if it would help but it's not much better, wondering what else I might try.

[SeanP]

Sorry I messed up with the multimeter I was on DC Volts! not sure if that's enough to get a belt of it though.
Anyway better get another cap ordered up.

[tm america]

I have had several of the powermax 65 retainers with the threaded section that falls off while cutting seems the expansion and contraction cause the plastic part to separate from the brass part.. mine would be fine when it cooled down but when they are hot the threaded section slides down.. i have floating heads on my machines so they never see any real down pressure also magnetic torch mount so no side loading either ..The last one the threaded section fell completely off when the torch picked up to rapid to the next cut.. This is when i noticed there is a design flaw as the part is just a press fit no ridge or anything to keep it from moving ..I also had a few 45 retainers crack and separate like that same thing happening as far as i can tell .Looking to get some of the chinese knock off to see how they do.. have not had any luck with the hypertherm made ones