melting nozzle?

[wagin]

I recently bought a MM252 and running it hot, melted the black plastic ring that tops the nozzle. Is this ring important? What should I do?

[aametalmaster]

You can buy a new shock washer. Mine has been fried for about 3 years and the gun still works fine...Bob

[walker]

I have run my gun hot before, but yours looks like it got real hot due to the color of the contact tip, as well and the melted washer. You might want to time your welds a bit to make sure your are in the ballpark of your duty cycle, so that you don't cause undue harm to your machine.

[ace4059]

That black part is called the insulator. Yep, they can melt. Dont burn up your gun.Were you running short arc, glob, or spray? I would switch to a bigger gun if you are going to run it in spray arc.

[Frank Motoweld]

If you want to do yourself a favor,get a Bernard Centerfire conversion kit for your gun.It'll take a lot more than that OEM stuff

[travlinbumm]

If you are running within the duty cycle of the gun, then check your connections. Loose ground clamp, cable to clamp connection, ground cable to machine connection. Check the work cable connections too. Loose connections in the gun can also cause excess heat.

[wagin]

thanks for all the info. I am spray arcing running 98/2. I have not heard of a Benard center fire kit?

[down19992000]

I hear everyone on a lot of forums rave about the bernard centerfire gun and to be honest I don't like it. My favorite had been the tweco eliminator series gun, maybe because I used that kind at my former employer's for 10 years. Where I work now we have the bernards and I just don't like them....Just my two cents.

[griff01]

That black part is called the insulator. Yep, they can melt. Dont burn up your gun.Were you running short arc, glob, or spray? I would switch to a bigger gun if you are going to run it in spray arc.

See AAmetalmaster's post also. That black part is called the shock washer.
The insulator (on a Miller gun) is located inside the nozzle. The insulator may get damaged but it will not melt.

Griff

[Frank Motoweld]

Centerfire for M-25

http://www.millerwelds.com/resources...ad.php?t=16832

thanks for all the info. I am spray arcing running 98/2. I have not heard of a Benard center fire kit?

[ace4059]

See AAmetalmaster's post also. That black part is called the shock washer.
The insulator (on a Miller gun) is located inside the nozzle. The insulator may get damaged but it will not melt.

Griff

Ok, good to know.
I don't run the miller guns, but the black rubber part on the bernard gun is called the insulator.
I've never heard it called a shock washer