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spot welder or not?


Vinnie
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Hey folks,

 

With all the welding required at the rear of my car (lower quarters, tallight panel) I’m thinking of treating myself with an early Christmas present being a 230V mobile spot welder:

 

https://www.toolmax.nl/telwin-digital-modular-230-230v-lasapparaat-spot.html?gclid=EAIaIQobChMIl4jltq-Q5gIVkOF3Ch29vwx2EAQYBCABEgLXHfD_BwE

 

Any thoughts or considerations on this pretty expensive tool? I’d very much be looking forward to not having to plug weld...

 

Cheers,

Vincent

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Although I don't own one I think it would make a good addition to the shop. It is on my "be nice to have" list. I had to remove my cowl and it took a month of Sundays rewelding back together using a small mig. A friend of mine use to own one. Because of the weight, he had it hanging by his engine stand with a cable and a spring. Could move it around easily and was able to use it for an extended period without getting to worn out. I would also buy a set of longer electrodes to be able to reach back into the quarter/tail panels.

Kilgon

 

 

"The only dumb question is the one not asked"

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I have used them before and just did not find them practical to use in most applications. To big and bulky. Can’t reach the backside of most welds so it can’t be used on a lot of hard to reach areas. I would invest in a better welder or tig welder before I would buy a spot welder. Once you get good at plug welds with a mig, there is minimal grinding and they look good. But if your going for factory perfect restoration then you need a spot welder. But I have done a lot of metal work over the years without one and honestly don’t think I would use it that much.

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Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

 

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Vinnie,

Here in most states in the U.S.A. it is not legal to do body panel replacement with this type of spot welder. The reason is that it is very operator dependent. At our stamping plant we did lots of spot welding for Ford, Toyota, John Deere and others. Your controls on the factory welders allow you to give the weld pulses that in the case of zinc coated materials first burns through the zinc with a low amperage pulse then it hit it again and maybe more than once to make the weld. During the course of the day you are required to do weld tear downs to check what they call Nugget size. The two panels cannot pull apart it has to pull a chunk out of one panel and leave a hole. If you fail a weld tear down you have to quarantine the previous parts back to your last good tear down and you might have to add welds or scrap them. You get about 3 cents per spot weld as a supplier to automotive so not big money.

Now all that said I do have a Miller Spot welder 220 Volt that I have used successfully, but it is not legal to do work for others. 

Obviously the factory units have water cooling to the weld tips and they are quite large over 100 lbs. so they have balancers attached that allow the tips to turn on any angle and remain perpendicular to the metals surface. Most today are attached to a robot that does that easily. There are schedules programmed in for weld tip changes or in the case of a robot you have an automated station that actually recuts the tips while on the welder. The points mash out and get too large and the current is not concentrated enough. 

There are some smaller Home or Small Shop units that do have water cooling and better controls and will do a much better job. You might do some checking and see if you can rent a unit since you are not going into the Beater Shop business. 

This is similar to mine. https://www.ebay.com/itm/MILLER-PORTABLE-SPOT-WELDER-WELDING-MACHINE-LMSW52-LMSW-52-18-220V/133252727339?hash=item1f067b422b:g:YsUAAOSwEDFdxwRj

If you do go with the one you are looking at you will need lots of practice. It is up to you on how long the current is on, you pull the trigger. You will need a set of the long reach arms to get to all of the weld and you will probably not be able to get to all with spot welder. You will need lots of clamps to get everything in place and correct location. 

A big CAUTION. The weld arms will get very hot I burnt a friends arm helping me once really bad and it just touched him for a second. Keep a big bucket of water handy so you can quench the arms to cool. As the arms heat up the resistance changes so your welds change. 

You will need to remove any of the so called weld through primer on your panels. At the factory on seams they used and expanding weld through seam sealer. Once welded and in paint operation the heat makes it expand to fill any gaps. I doubt you can locate that for personal use. You will need to practice a lot, do weld tear downs and check that your weld tears the metal and that the spots do not pull apart. The welder will come with some instructions. You cannot weld really close together. The current will jump to the adjacent weld and you will get a bad weld if too close together.

I will get you a welder name that is a step ahead of what you are looking at but much more cost. The name escapes me right now.

The weld tips are not cheap around $30.00 US for typical pair. There are pointed, round nose, flat and combinations of each for different situations. We used some that had been cryogenic treated to lengthen life and also Tungsten tips.

How I ended up with one was my X wife crashed the 20th. Anniversary Mustang I bought new. It required a frame pull of over 4 inches to get the front rails back. It also required new radiator support, new left and right inner panels from shock tower forward. 

Was on frame machine first the we got all the panels clamped in place and measured out. Then we welded them with the spot welder. Would stop and cool it and do a test weld on scrap part and check. We rebuilt and painted the car in 9 days and worked full time job while doing the repair. 

As the X wife was a horrible driver she crashed it again and needed new front fenders hood again. The radiator support and inner panels were not as bad but did need a frame pull. I was there when he pulled it and figured the panels would tear apart but the spot welds held and he got the front end back to spec. 

So yes you can get good welds with the portable spot welder and yes they will look original. It does take some learning and skill which we all have seen how capable you are at learning new skills. 

There are rebuild shops in the U.S. that do have tested and approved spot weld equipment for doing panel replacement but they are expensive. AMD and Grave Robbers are two of the shops in Georgia that have good equipment but they still use MIG and TIG in places. 

Here is a link to info on AMD. They are more into GM and Chrysler but I do see the Ford logo there also. They have done bodies for my friend that does restorations. You can see one of the spot welders there with the heavy arms that can really clamp the material together. 

https://www.amdinstallation.com/

Grave Robbers is not as good a shop and neither of them do the body work just panel replacement. 

https://www.graverobberssheetmetal.com/index.php/custom-frame-jigs

As you see both shops do use chassis jigs to keep everything in alignment which makes it much easier to get good panel alignment. I think both have online quoting also. You can get a price of about any type work without being there. 

You can see lots of clamps in the shop at AMD and you will need also. You should figure out some way to support your car in the same way they do. Can be stands of wood or jack stands that you shim to get the chassis level on the original Datum points. 

I will get you a name for the next step better welder. You might uses it then sell it unless you are going to do another? 

When you are spot welding if you see big flashes and sparks going everywhere the metal is not being clamped good enough which causes an arch that splashes the molten metal out. 

We use to weld the front floors for the Econoline van the whole floor for the Aerostar Ford van. The BMW X-5 floor pans. Lots of sub assemblies for Ford, and BMW. We had hundreds of welders.

I am sure you can do a great job as you always do it is all dependent on panel fit to get a good weld. I also like to braze some areas right on the edges for insurance.

When a man is in the woods and talks and no women are there is he still wrong??:P

David

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I'll agree with Geoff, it's just not a practical tool for what you're doing.

 

I have plenty of experience with industrial spot welders and I can see all sorts of failure points on this unit just like David pointed out. I did all of my panel replacement with a MIG doing plug welds. You do get pretty darn good at it after a while. Don't use a grinding wheel, use a flap disc. A quality disc will grind like a wheel, but leave a nice smooth finish.

 

 

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Although I don't own one I think it would make a good addition to the shop.  It is on my "be nice to have" list.  I had to remove my cowl and it took a month of Sundays rewelding back together using a small mig.  A friend of mine use to own one.  Because of the weight, he had it hanging by his engine stand with a cable and a spring.  Could move it around easily and was able to use it for an extended period without getting to worn out.  I would also buy a set of longer electrodes to be able to reach back into the quarter/tail panels.

 

 

Hmm, sounds like I will scratch this off my "be nice to have list" after reading the other post.   :whistling:

Kilgon

 

 

"The only dumb question is the one not asked"

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That handheld spot welder you posted the link to looks pretty cool- WAY different than the cheap Harbor freight ones.  I like the tong setup on it, looks like it would be much easier to make custom tongs for it over the harbor freight spot welders.  I found that I was only able to use my spot welder to secure the outer wheelhouse to the quarter panel and the quarter panel to the trunk drop.  I couldn't really fit it into the tail lights to spot weld the tail to the quarter panels.

 

My only gripe with the welder in the link you provided is that it is a fair amount of money for the gamble.  It would be interesting to read the instruction manual and see what those various menu buttons on the side of it do.  It looks like it can do a timed spot based on thickness of metal just from looking at the side of it.  I also see something that looks like a square wave on next to a button.  Is it something you can purchase from a brick and mortar welding store?  If so will they let you try it?

 

 

 

When I was setting up to do my car, I had spare trunk drops that I cut up for destructive testing.  I would spot weld them together, and rip it apart to see what failed.  After I was satisfied that the weld was just as good as a plug weld with my mig I went about my merry way spot welding.

 

I don't use my spot welder often, but it is nice to have for random sheetmetal projects - that being said It would be hard for me to justify spending that kind of money on one.

 

Made flashing for my chimney with it….  Note- the tongs in the photo were NOT the ones I used for the outer wheelhouse to quarter panel.

IMG-0252.jpg

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OK fellas, I feel some negative vibes here, now surely it can't all be that bad! ;-)

 

I don't actually read that many failure points. A lot has to do with using the correct setting and preparation.

This Telwin machine (about 800-1050 USD) can do pulses, too. Sure, you can't reach everywhere but I wasn't planning to. Leaves plenty (a lot, actually) of places that *can* be reached though. Tests can be done before hand. You didn't think I was going to instantly use it on my car without testing I hope?

 

Also, it makes no sense to first drill a hole in a panel so that it can be plug-welded.

 

Thanks for all the cautions, they are noted!

V.

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> That handheld spot welder you posted the link to looks pretty cool- WAY different than the cheap Harbor freight ones.

I thought so!

 

> I like the tong setup on it, looks like it would be much easier to make custom tongs for it over the harbor freight spot welders.

It's very easy to make your own I think but they also sell different ones for it.

 

> I couldn't really fit it into the tail lights to spot weld the tail to the quarter panels.

Anything from here that would do the trick perhaps:

- https://telwin.com/export/sites/default/it/doc/allegati/Bracci-puntatura_DigitalSpotter_Modular_DigitalModular.pdf

 

> My only gripe with the welder in the link you provided is that it is a fair amount of money for the gamble.

Yeah, it is expensive but I got a good feeling about it.

 

> It would be interesting to read the instruction manual and see what those various menu buttons on the side of it do.

- https://telwin.com/en/prodotti/?id=823016&clmer=82&lingua=E&descProdotto=DIGITAL%20MODULAR%20230

 

> It looks like it can do a timed spot based on thickness of metal just from looking at the side of it.

Correct.

 

> I also see something that looks like a square wave on next to a button.

Also correct.

 

> Is it something you can purchase from a brick and mortar welding store? If so will they let you try it?

That's what I've been trying to fnd but nothing sofar. In the Netherlands, everything you order online (at least from a Dutch webshop like this one) can be returned though, especially if the product doesn't live up to its expectations. So it's a matter of trying it out and deciding if it's OK or not.

 

The metal you used for testing is the same as I'm going to test on and what I need to weld.

 

Thanks!

Vincent.

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I have a Miller 220v. Most of the time you need more reach and around things. More reach you lose clamping force. Trying to force more clamping the tips become misaligned. Today the Miller just collects dust.

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I'll agree with Geoff, it's just not a practical tool for what you're doing.

 

I have plenty of experience with industrial spot welders and I can see all sorts of failure points on this unit just like David pointed out. I did all of my panel replacement with a MIG doing plug welds. You do get pretty darn good at it after a while. Don't use a grinding wheel, use a flap disc. A quality disc will grind like a wheel, but leave a nice smooth finish.

 @ Hemikiller, did you mean Eric?  

 

 My comment would be fine for setting up and tack welding only, then mig or tig. Heat control is critical so panels don't warp or oil-can.

Geoff.

Geoff.

 I learn something new every day!

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Howdy from Idaho,

I have been a welder almost all my life. A great deal of it within the profession of tool and die making. The spot welder works well when it is performed at a certain skill level. Also a certain setting level with "very clean steel". Which is what you find on the assembly line at the Ford plants. Contamination within the spot weld will severally weaken its ability to hold. If you had a blow out and the car shook vilantly or a bent rim was run with vibration the welds could pop loose.

 

Dont get me wrong Im not saying you couldn't prep it correctly and weld it correctly with the spot welder. Im saying there are some factors that you cant control totally.

By drilling a hole this leaves the sheet metal very clean and ready for a weld. Improves the odds of no contamination. It also gives a stronger weld surface by increasing the surface area heat area.

We just finished a trunk, the drops, qrt panels, inner and outer fender wells, tail light panel on our Mach 1. We wire feed welded all of it. I feel confident it is a stronger way to do the job.

 

 

mustang-rear-qrt-replacment.jpg

 

new-trunk.jpg

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Thanks for your input! So I get it, required are skill, correct settings en clean metal. About that last thingy, clean metal, is bare OK? sanded? 80 grit or finer? Does it need to be primed in acid?

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You do not want paint on it. The two pieces being together is most important and that the tips align to each other. The welders in the stamping and assembly plants can put hundreds of lbs. of force to pull joints together. Look at how the rocker boxes are welded in our cars. You can see the distortion from clamping. They do use a weld thru sealer on most joints but you should not. Add sealer after you weld. 

I put rocker boxes, running boards and floors in VW bug with my Miller spot welder and also repaired my Mustang. 

You are very good a preparation of your parts which will help lots. When you get the longer arms on you will see that the clamping force goes way down so secondary clamps become important. 

Resistant spot welds hold most of the vehicles on the road together. But also remember back in the day when they built race cars they left the sealer off spot welded at the assembly line then they MIG welded at the race shop. Some flex is good, look at a large truck frame, tractor trailer. You will note that nothing is welded either bolted or riveted. If it were welded it would fail in a very short time.

That is one fault I had with John Deere. They insisted on MIG welding everything. I asked about hot rivets and they said Deere banned them years ago and would not use them. So you will see lots of stress cracks on Deere equipment show up over time. They have to use much heavier metal also to prevent failure.

When a man is in the woods and talks and no women are there is he still wrong??:P

David

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I don't have a lot of experience with welding, other than working on my Jeep and Mustang (more so the Mustang, since I pretty much had to put it all back together).

 

Plug welding using a wire-feed MIG set-up worked best for me.  We had an awesome Miller spot welder, and after about 2 hours of fighting with the damn thing, I produced exactly 1 viable spot weld when trying to zap down a patch panel on my Jeep's passenger side rear corner.

 

Once I put the spot welder away and busted out the Miller wire-feed MIG, stuff started happening.  I practiced on a few pieces of scrap, and was immediately much happier with the results.

 

My skills developed over time and I'm at the point where I will trust my welds, even though they're not as pretty as more experienced welders can produce (some of those guys are artists!).  I've burned some welds that are absolutely inspirational... and popped out so many more dog turds it's not even funny - which I blame on my not knowing how to properly set-up the welder for the weld.  Our local community college offer a welding class, which I plan on taking someday so more of my welds will be of the 'inspirational' sort.

 

But honestly, if given the choice, I would plug weld all day/every day over spot welding.

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Eric

mach1sig2.gif

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Thanks for your input! So I get it, required are skill, correct settings en clean metal. About that last thingy, clean metal, is bare OK? sanded? 80 grit or finer? Does it need to be primed in acid?

Hi Vinnie,

 

No need to sand it or prime it. You could use a hand spray bottle with muratic acid in it to clean the metal. Or just use good ol soap and water removing any oil residue from over seas shipping. 

As you can see my wifes Mach was a terror to get done. You will be just fine, take your time and go slow. They built these machs in a day on the assembly line.........but we cant do that at home.

Send us some photos of your progress sir.

Thanks

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