Catching back up on some of your test videos. You've done some good ones over the years.

Its 4:30 am here, was going to purchase dome 3m weld thru today when the store's opened, thank you for your test,just saved me from wasting money,after your test i decided to purchase the copper weld #2, thanks again Double K

I think those plug welds look great. I really like the Medallion. Now I know, if I cant get the Medallion, to get the Upol. Thanks for the test. Good stuff!

This was what turned me onto buying the Copper Weld Through Primer.

Cool video Roger! Really helps to see what really works and what does not. Makes a difference in the build.

To Robert White or RogerWhere did you buy RS 512 Medallion for $18.00 a can, it cost me about $23.00 for one can plus $12.00 for shipping? I only bought one can because I had never used it before and wanted to try it first. I really like it and want to order more and would like to find a better price. Price and shipping were the same for more then one can...Thanks for the testing Roger, Enjoy your videos!!!

You can tell a big difference in both of them. Very good test.

Great test Roger I like it when you dive into the issues.

If you would have put weld thru on the back side of the strips you plug welded on, then you could have cleaned up and painted that and put it outside for a test. Then in a year or so you could have cut it apart and see if the welds had rusted. That would have been a test I would be interested in. looks like both those primers weld great.

Good test and good to know these are both good to weld thru ...... Unfortunetly for me I cant seem to find either brand up here in Canada......Thanks for doing these tests on weld thru primers cause at least now I know not to waste my money on the 3M brand which is crazy expensive here Cheers MrFireman ..... always good videos , learn lots from watching thanks

I like the test. But I also agree that as the test panel became more heat soaked, the welds got flatter and penetrated nice. The 3m weld thru definitely sucks and spatters too much and I always find the can plugs up before it's empty. Even though I always purge the can when done

UPOL has some good products yet some who use their fillers have said they are different as they use a lot. I am just curious like many on how both perform between the welds. I have why less spot welding to do than most. A new GM Auth tailgate seems to be thicker than the truck was build. So now I have to move the tail light pocket out to meet it. Oh well! Found rocker panel did not provide for fender relief and needs fixed. So more unplanned work to do. I just want to see the level weld protection it provided. Good job again in this test!

Hi, That was a good review, thank you for sharing it with us. I would be interested in how the panel looked after you detached the two pieces and how it looked if left out in the elements too. I am researching WTP's and the Medallion looks real good especially when compared to the upol and the price too. Kind regards Paul (from "48-SPOKES") UK

Thanks for posting and sharing! Great comparison video...

Wow, those worked really nicely. Wish I had seen that before I did all my welding!

The SEM copper weld thru primer really sucked like you said you had to scrape the top off and it would splatter and if you didn't take the the top where you were going to weld the weld would come out like crap. All so for $25 a can you might get one use as the can would plug up even after you would purge the can, summit sent me a new can and it wouldn't even spray out. Looks like that stuff works!

Excellent video

Nice welding thanks for up showing

I have issues using the copper stuff. Every time I don’t clean it off it wants to blow up and get all nasty splatters etc. when I clean it off it does better until maybe when I hit a spot I missed. If I don’t use it at all things go all around better. I did side by side test same metal same settings and it was night and day. I also noticed if I test with say a plug weld let it cool and when using the copper I sometimes here a ring sound and sure e would it let go. Don’t use it no issues. Is it just me ha being these issues with this stuff? It’s not cold because I can see burn through coming through the back. So I’m not sure if maybe it’s not mixed well,just bad or what the issue is.

the welds look great to me. should put some on the backside to see if it burns off

Do you feel like one of these (Upol copper vs Medallion 512) is better than the other? I would think the etch weld would be better. Ive just tried the 3M Weld-Thru II but noticed that it scratches off the sheet metal very very easily. I'm currently re-banding my windshield due to rust and have new 1" wide 18 gauge strips that mate against the original base layer so I need something like this in-between the two layers where they will face each other. Each strip has maybe 10 plug weld holes to attach it to the base panel. Since I drilled them out I got a pair of spot weld vice grips off Amazon that has a thick copper backing plate so you can clamp it down and weld the hole, un-clamp, move to the next hole, etc.

Based on this experiment; looks like I will start buying medallion. Maybe they will send you some free primer!

Do you know how good is the Medallion against rust? Thanks

the RS 512 is about 18.00 a can almost 1/2 the price

I watched all these weld thru primer videos he made so far .... is there a follow up to this one ? I'm curious how these fared in between the seams. p.s. I see Upol on eBay for $19, ($30 on Amazon) and the Medallion you need to find a rep to get.

what is your speed set 2. I have a mig and don't have to much ex.

Cool.

A