Hypertherm 1650 torch not firing some times

[yogi]

i have a hypertherm 1650 g3 series plasma cutter. the problem is when Im cutting with a 60 amp process my torch will not always fire. it will make a few pierces then wont fire untill i tap on the ohmic. once you do that it will fire for a few cuts and then do it again...... ive only noticed it on a 60 amp process tho.

[illusivedf]

Make sure your consumables are just finger snug. I used to have similar problems until somebody told me not to tighten the consumables very tight. So I always just used my thumb and one finger rather than a full fist grip so to speak.

[KIDTech]

Not sure if this will help you but it did me, in my case it was the consumables sticking with my PM65. I got cleaner air and it helped a lot.

[yogi]

Thanks , I do always only finger tighten my consumables but , I have tried leaving them looser and over tightening them to see if it makes a difference and I have a pre filter, air cooler and a post filter before my torch so my air is cool, clean and dry. I should have also mentioned all parts are hypertherm, so not sure why this keeps happening.

[jimcolt]

Two components that often do not get changed....the swirl ring and the retaining cap are often the cause of misfiring. The swirl ring has 3 major functions, one of which is as a slide bearing for the moving electrode in the torch. Over time the swirl ring wears to a point that is will inhibit the movement of the electrode. It the electrode sticks...the torch will not fire. Tapping the torch may loosen it enough to work again. Have you changed the swirl ring recently?

Retaining caps provide the routing for shield air flow, as well as for holding the consumable parts in a concentric manner. As the cap wears, the air passages can clog and the concentricity of the consumable can be off. If you see varying cut angularity or experience misfiring, change the retaining cap.

The electrode in the G3 style torch seats and gets its electrical contact on a silver plated plunger inside the torch. If the inside of the torch is not perfectly clean (should be wiped out periodically with a cotton cloth) the silver plunder can get dirty or pitted, this will cause misfiring as well. Clean the plunger....if it is badly pitted it is due for replacement. Replacement of the plunger is covered in the service manual that you can download off the Hypertherm website.

Best regards, Jim Colt Hypertherm

[yogi]

Thanks Jim, we have tried an all new set-up before and it seems to work fine for a little while then goes back to not firing. I have not tried cleaning the torch, I've only used compressed air to blow it out, I am going to try that. I will let you know the results. I also forgot to mention that i have the duramax torch, if this makes a difference.

[jimcolt]

The Duramax does not have an internal plunger...rather it uses the spring electrode. Usually misfiring with the Duramax is because your cut air pressure is too high.....

Jim Colt Hypertherm

[yogi]

I did clean the torch with a q-tip and put a new set of consumables ( exept the ohmic it was replaced a few weeks ago ) and it did seem to work better, it did not misfire yesterday with over 2 hours of cutting and 700 pierces, this morning however it has happend a few times already. Our air to the hypertherm is anywhere from 105 to 155 psi and the only regulator is the built in one on the hypertherm. Whats your recommendation for a good compressed air regulator ? Thanks.

[yogi]

After doing a little more research figured out with the duramax torch air is supposed to be at 70 psi not the 80 i was running it at, so we set the hypertherm at 70 psi and we did get a new air regulator before the hypertherm and have that set to 80 to reduce any surges or pulsing in the line. This past week it has only not fired twice, compared to probably hundreds of times ! Thanks for the help.