Miller Dialarc

[Jorville]

I bought a Miller Dialarc HFP new back in 1980. the cooling fan started to make noise after 30 minutes of run time, I called Miller and they said the warranty had expired. The machine had sat on it's shipping skids for a year before I got it wired up so I was SOL. After the fan noise it has sat on it's shipping skids for 35 years or so. Couple of weeks ago I wired it up and the motor still makes noise after a bearing house told me the bearings were good. Turns out the motor housing was machined .006 thousands too much. I fixed that with shim stock.

The machine seems to arc weld fine, I did not do much, I want the TIG capability. I feel there is something wrong with the high frequency. With both switches in the correct position, gas turned on and gas at the torch, the foot pedal pressed down, there is no high frequency start. I have to scratch start the arc. and when I do the tungsten burns back, and if I press the pedal down further the tungsten burns back faster.. I am tempted to have a service tech come out and take a look at it. You guys have any thoughts or ideas on what might be the problem. This machine has sat in a un-heated building for the last 35 years, would the cold wreck electrical parts of the machine?

 

[Mysfyt]

I would start by cleaning my points and then setting the gap. The image shows what they look like. I think they are on the R side of the welder as you are looking at it, but I'm not sure. Clean with some fine emery cloth and set the gap to .015".

The image shows the lower left point missing, BTW.

 

[Oldtink]

Here is the op manual if needed. Tungsten burning off? Sure you have sufficient gas flow at the torch and no leaks?
https://www.millerwelds.com/files/owners-manuals/O315_MIL.pdf

 

[Mysfyt]

I stand corrected. After reading through the manual, the points are under the front panel and the recommended gap is .008"

 

[Jorville]

Thanks Mystyt, I will look at that. I don't know what makes these thing work. When they are new it is magic. I can see where there could be some corrosion.

 

[Jorville]

Oldtink, I thought of that also. I have turned the machine at work on and started the arc and burned off some tungsten and said woops, no gas. This thing won,t even start the arc on the start position. The gas flow is at 25 and inside a building. After pre flow there should be Argon.

 

[Jorville]

Mysfyt, You were right on. The machine sat for so long the points were all corroded up. I took the point holder off the machine and cleaned out the bores the points are in and cleaned up the points. I have high frequency now. I still have a problem with the tungsten burning back though. I might have a bad flow meter I see when I push the pedal down the flow is 20 (a little high I think) then the flow drops to nothing or a little of nothing,

 

[CalG]

polarity correct?

dc Rev will ball up an electrode in a big hurry.

 

[Jorville]

polarity correct?

dc Rev will ball up an electrode in a big hurry.

I have it set for DC straight and the tungsten just burns back. Now I am seeing the gas flow go down to zero or very low. I have to find out why.

 

[CalG]

shove the torch on a plastic pail of water, and watch the gas flow as bubbles.
Be careful of what might be touching, There is welding current there too. ;-)
Stuck diaphragm in the regulator? Is the gas rig 35 years old and never been used? NOT GOOD!

Just a point.

As far as diagnostics over the internet goes. There is a HUGE difference between a tungsten that "burns back", and one that "burns black".

 

[Mysfyt]

Mysfyt, You were right on. The machine sat for so long the points were all corroded up. I took the point holder off the machine and cleaned out the bores the points are in and cleaned up the points. I have high frequency now. I still have a problem with the tungsten burning back though. I might have a bad flow meter I see when I push the pedal down the flow is 20 (a little high I think) then the flow drops to nothing or a little of nothing,

Glad to hear you're making progress!

Sounds like a regulator issue as far as the gas flow issue. Got another one to try?

 

[Jorville]

Mysfyt, CalG, Everything seems to be working fine. Part of the problem, or maybe most of the problem was my memory. I had no gas flow because at the torch is a gas on and off knob that I would forget to turn on every once in a while. That was why the flow meter would go to zero.
That torch used to be used out of the shop on a DC machine and a scratch start. I don't think I will forget to turn that valve on anymore.
I went to the book and checked on tungsten size and amperage and ceramic cup size. Once that was right and gas valve was on at the torch everything was OK for the short time I tried it. Now I just need to warm up some.

At work I used a 350 scyrowave and they seem to be different than the old machines. I found out the scyrowave does not need the pure tungsten for aluminum like the older machines.

 

[Mysfyt]

Happy to hear you're up and going. Enjoy!

 

[Arc weld]

Mysfyt, CalG, Everything seems to be working fine. Part of the problem, or maybe most of the problem was my memory. I had no gas flow because at the torch is a gas on and off knob that I would forget to turn on every once in a while. That was why the flow meter would go to zero.
That torch used to be used out of the shop on a DC machine and a scratch start. I don't think I will forget to turn that valve on anymore.
I went to the book and checked on tungsten size and amperage and ceramic cup size. Once that was right and gas valve was on at the torch everything was OK for the short time I tried it. Now I just need to warm up some.

At work I used a 350 scyrowave and they seem to be different than the old machines. I found out the scyrowave does not need the pure tungsten for aluminum like the older machines.

Syncrowave 350 or Dynasty 350? The Dynasty is an inverter that doesn't use pure tungsten but the Syncrowave 350 would use the same tungstens as the Dialarc HF. Pure and zirconiated used to be used for aluminum but now I think ceriated, lanthanated and rare earth tungsten can maybe be used on transformer machines and inverter machines. There's a chart and article on the net that explains the different tungstens for different machines.

 

[Jorville]

Syncrowave 350 or Dynasty 350? The Dynasty is an inverter that doesn't use pure tungsten but the Syncrowave 350 would use the same tungstens as the Dialarc HF. Pure and zirconiated used to be used for aluminum but now I think ceriated, lanthanated and rare earth tungsten can maybe be used on transformer machines and inverter machines. There's a chart and article on the net that explains the different tungstens for different machines.

When I was using the 350 syncrowave on aluminum I would use the pure tungsten. I think I would round the end but the ball never got any larger. When I used a dial arc many years ago the ball would continue to grow. There was another guy at work that said that pure tungsten was not needed when using a syncrowave. The pure tungsten used in the dial arc and syncrowave did not have the same characteristics that was why I thought the pure was not needed for the syncrowave.

Many, many years ago my older early former co-workers used 2% thorated on everything. They even used AC on mild steel. When I used DC straight polarity on mild steel I was laughed at and criticized.

 

[Oldpath05]

I'll be looking at a Miller Dialarc 300 this evening, guy wants $400.00 delivered from 60 mi. away, sounds like a fair deal. He said it runs on 220 volts, wondering is that true? Not sure how old it is, he showed me a picture of the front, hard to find a good picture online but it looks like this>>>> Miller 3 Amp Dial arc Welder | Trade Me What thinkest tho?

 

[yomax4]

I'll be looking at a Miller Dialarc 300 this evening, guy wants $400.00 delivered from 60 mi. away, sounds like a fair deal. He said it runs on 220 volts, wondering is that true? Not sure how old it is, he showed me a picture of the front, hard to find a good picture online but it looks like this>>>> Miller 3 Amp Dial arc Welder | Trade Me What thinkest tho?

Could be as old as the 80's or as new as the early 2000's. You can call the serial number in and see, In any event it will serve you well albeit a transformer unit.
( I just don't like to ball tungsten for AC ) Probably be able to put it in your will some day.

 

[Oldpath05]

Just had Miller Dialarc 300 dropped off, little dusty, didn't have any rods to try it out on but he said it works good. It has the same plug has my small Miller mig welder, plugged it in and the fan came on so that's a good sign, I'll have to get another breaker, outlet and bigger 220 cable anyways, next month's project.

So now that I have the Serial No. and Stock No., do I call the Miller hotline with that so I can find out how old it is and maybe possibly get the instruction manual for it?,

 

[MinnesotaDaveChalmers]

I'll be looking at a Miller Dialarc 300 this evening, guy wants $400.00 delivered from 60 mi. away, sounds like a fair deal. He said it runs on 220 volts, wondering is that true? Not sure how old it is, he showed me a picture of the front, hard to find a good picture online but it looks like this>>>> Miller 3�� Amp Dial arc Welder | Trade Me What thinkest tho?

I've never seen one that didn't run on 220v. But check the tag to be sure of course - it's always listed on the tag.

I like dialarcs, they weld very well in my experience.

 

[stihlman]

You can get the manuals online. The Dialarcs are great machines. Great arc quality on stick. You got a good deal