[7.62x39]

George,

I was going to send you a PM regarding this, but I know other members have been talking about buying a spot welder, and I figured others may also want this info.

The BBT just dropped off my spot welder (and another box from Tapco, kinda like Christmas).

I was wondering if you had any measurements or drawings on how you modified your lower tong?

Also the upper and lower tongs appear to be Identical, yet they carry different part numbers in the breakdown.
Have you discovered any differences between the two?

For those of you who missed the other thread on these, Harbor Freight has them on sale for $149. with free shipping (reg price $199) the weird part is Northern hydraulics get $469. for the same welder.

 

[mbadboyz]

Yeah goerge....how did you make the tong for the spot welder?? I did see your post on it, but I have one question:
Both ends have a point. What did you use for the point when modifying the lower?

 

[7.62x39]

The tips are replaceable, they have a 8x1.25mm stud on the bottom.

I think I saw a pic of George's somewhere, IIRC he reused the same tip, I assume he just threading the lower tong to accept.

It looks like the tong will need to be face cut in order to gain the necessary clearance.

 

[sks_hunter]

I know he posted a recent pic... I'll look for it...
hope nobody minds me reposting that pic...
any objections, pleze let me know, I don't want to step on any toes.

 

[7.62x39]

SKS,

Thanks, That's the pic I was thinking of.

 

[mbadboyz]

gtbehary went into it from the side though. That pic shows it from the end.

Here is the other photo that was on the other post:

http://www.gunco.net/forums/attachment.php?attachmentid=756
http://www.gunco.net/forums/showthread.php?t=1543&page=2&highlight=spot+welding


[url="http://www.gunco.net/forums/attachment.php?attachmentid=756&stc=1&thumb=1"]http://www.gunco.net/forums/attachment.php?attachmentid=756&stc=1&thumb=1
[/url]

 

[7.62x39]

It looks like it could go in either way.

That must be why the bottom of the lower tong is also faced, I was wondering about that.

 

[7.62x39]

mbad,

Thanks for the link.
I hadn't noticed, George mentions in that thread, that the pic was gunnysmiths.

Good info from Toten kopf in that thread also.

 

[sks_hunter]

ah, yes... I remember now
he used a piece of copper tube flattened and bent into an offset.

 

[erikk]

I just ordered another 5/8 copper rod from Mcmaster-Carr. a 12" piece was around 10.00. Then ground the end flat for about 1 1/2 " drilled & tapped it for the tip off of the one that came with the HF welder. Works great.

 

[mbadboyz]

I just ordered another 5/8 copper rod from Mcmaster-Carr. a 12" piece was around 10.00. Then ground the end flat for about 1 1/2 " drilled & tapped it for the tip off of the one that came with the HF welder. Works great.

Sounds easy enough. Are you going in from the side or front? Do you have any pics you can post?

Mark

 

[tarawa]

I come from the side when there is clearance problems (around the ejector) and from the end when it is clear. I also bought some copper rod from McMaster-Carr, but I am going to make some different tips. I found out that you must have identical tips or one burns up. I guess it is the difference in resistance. I also flattened the tips to make a bigger weld, but I don't know if it is necessary.

 

[mbadboyz]

I come from the side when there is clearance problems (around the ejector) and from the end when it is clear. I also bought some copper rod from McMaster-Carr, but I am going to make some different tips. I found out that you must have identical tips or one burns up. I guess it is the difference in resistance. I also flattened the tips to make a bigger weld, but I don't know if it is necessary.

I have not purchased the spot welder yet. Are those rods solid?

 

[7.62x39]

I have not purchased the spot welder yet. Are those rods solid?

Yup, 5/8"X 8-1/2" solid copper.

 

[7.62x39]

... I am going to make some different tips. I found out that you must have identical tips or one burns up....

George,

In gunnysmiths pic, it looks like he is using the original tips.
Are you saying the rods must also be of equal length/mass?

That is what concerns me with using copper pipe as in TK's pics.

I know that voltage would not be a concern, but welding is all about amperage, and there is no way that the hollow copper pipe will carry as much amperage as a solid copper bar.

 

[tarawa]

I think that they sould be pretty close, especially with the 220volt model. I made a few tips with some 1/4 -20 copper bolts and they disintegrated after one try...poof!

 

[erikk]

At first I used the flattened copper tubing with a copper rivet that I had laying around. It worked great for 2 builds but then started to burn out on the tip. I re filed the tip and again it worked for another 2 builds before having to repeat the process. (I have the 115v) The solid rod with the original tip are more stable and seem to last longer before they have to be re dressed.

George: you hunkering down?!?!Could be a hairy weekend!

 

[7.62x39]

I ordered a copper bar from M-C, it should be here in a couple of days.

For anybody else looking to build a new lower tong, the M-C part number is 8966k221

http://www.mcmaster.com/