Weldable primer

rallye bob · 11-30-2010, 09:08 PM

I am doing some bracing on my GM "A" body rear suspension LCA mounting areas.
My question is.... What is your experience with using weldable primer and mig welding?
Tell me if this works and what steps I need to take in the prep. of this operation? TIA......

Rich Biebel · 11-30-2010, 09:55 PM

I repair welding equipment. Have been doing this for 15 years. I test everything I repair especially mig machines......I have no experience with a "weldable primer" and never heard of it......but I know from experience....mig weldling "thru"any paint is difficult to get it started. You can clean one area and get the weld started and it burns off the paint in front of the weld. Mig and tig welding like clean material......

I am sure the product works but probaly not nearly as good as the manufacturer says.....My guess is it has conductive properties, meaning it does not insulate between the gun and the ground. It also probably has high metallic content and the paint burns off without contaminatiing the weld site

Do a google search and go to any forum where pro welder/operators talk about things like this......I would bet they say they hate it and grind it off.....LOL

Crisco · 11-30-2010, 11:40 PM

Bob, what you are looking for is a weld thru primer. SEMS brand is good. You can get it at any automotive paint store. Clean the weld areas to remove oils etc. Spray the primer in these areas and let it completely dry before you start welding.

http://www.google.com/products/catal...d=0CCIQ8wIwAA#

Dion Hildebrandt · 12-01-2010, 02:05 AM

There are many brands of weld thru primer, we use 'UPOL' copper rich ourselves. The weld thru primer is meant mostly for welding sheetmetal together, the primer melts and surrounds the weld or 'hot spot' to conceal the spot from potential rust issues. for welding the LCA areas clean the area thoroughly as it is not an ideal location as it will most likely be overhead and cramped quarters ,and undercoat or paint afterwards. The weld thru primer may cause a problem for striking an arc and will promote spattering of the weld. An alternative is to use POR15 afterward, that s**t is incredibly tough and will glue the lid to the can if your sloppy with it haha, hope this helps

K Stubbs · 12-04-2010, 10:07 PM

Actually you shouldnt even need a weldable primer in that location, just clean it good and weld it. Primer it after. You will get a much better weld, and if its a racecar you shouldnt have rust issues there anyway if painted properly. I do alot of racecar fabrication, mostly tig, but never use a weldable primer.

Mark Yacavone · 12-04-2010, 10:29 PM

I 've used that stuff on floorboard patches,etc at the overlap ,where it does work well.
It'll kinda melt away from the tack weld ,but still have a coating in place when you're done.
I agree with others...You really don't need it for chassis work.

Charlie Yannetti · 12-06-2010, 09:08 PM

I had a travelling body shop snake oil salesman sell me a can once.. I said ONCE.. tried it, put it on the shelf marked "EXPERIENCE", and never looked at it again.. follow the advice on this forum.. clean it good, weld it once, paint it right, never do it again..

rallye bob · 12-07-2010, 06:11 AM

Quote:

Originally Posted by Charlie Yannetti

follow the advice on this forum.. clean it good, weld it once, paint it right, never do it again..

Done.......... ;-)
Thanks, to all, for the great advice

11-30-2010, 09:08 PM	#1
rallye bob Member Join Date: Sep 2006 Location: Genoa, Illinois Posts: 489 Likes: 9 Liked 6 Times in 4 Posts	Weldable primer I am doing some bracing on my GM "A" body rear suspension LCA mounting areas. My question is.... What is your experience with using weldable primer and mig welding? Tell me if this works and what steps I need to take in the prep. of this operation? TIA......

11-30-2010, 09:55 PM	#2
Rich Biebel VIP Member Join Date: Jun 2007 Location: Northern New Jersey suburbs Posts: 2,319 Likes: 25 Liked 552 Times in 215 Posts	Re: Weldable primer I repair welding equipment. Have been doing this for 15 years. I test everything I repair especially mig machines......I have no experience with a "weldable primer" and never heard of it......but I know from experience....mig weldling "thru"any paint is difficult to get it started. You can clean one area and get the weld started and it burns off the paint in front of the weld. Mig and tig welding like clean material...... I am sure the product works but probaly not nearly as good as the manufacturer says.....My guess is it has conductive properties, meaning it does not insulate between the gun and the ground. It also probably has high metallic content and the paint burns off without contaminatiing the weld site Do a google search and go to any forum where pro welder/operators talk about things like this......I would bet they say they hate it and grind it off.....LOL __________________ Rich Biebel S/C 1479 Stock 147R

11-30-2010, 11:40 PM	#3
Crisco Member Join Date: Jul 2005 Location: Hendersonville, TN 37075 Posts: 226 Likes: 4 Liked 47 Times in 21 Posts	Re: Weldable primer Bob, what you are looking for is a weld thru primer. SEMS brand is good. You can get it at any automotive paint store. Clean the weld areas to remove oils etc. Spray the primer in these areas and let it completely dry before you start welding. http://www.google.com/products/catal...d=0CCIQ8wIwAA#

12-01-2010, 02:05 AM	#4
Dion Hildebrandt Member Join Date: Nov 2008 Location: calgary alberta canada Posts: 383 Likes: 0 Liked 0 Times in 0 Posts	Re: Weldable primer There are many brands of weld thru primer, we use 'UPOL' copper rich ourselves. The weld thru primer is meant mostly for welding sheetmetal together, the primer melts and surrounds the weld or 'hot spot' to conceal the spot from potential rust issues. for welding the LCA areas clean the area thoroughly as it is not an ideal location as it will most likely be overhead and cramped quarters ,and undercoat or paint afterwards. The weld thru primer may cause a problem for striking an arc and will promote spattering of the weld. An alternative is to use POR15 afterward, that s**t is incredibly tough and will glue the lid to the can if your sloppy with it haha, hope this helps __________________ Dion Hildebrandt 6009 STK H/SA

12-04-2010, 10:07 PM	#5
K Stubbs Member Join Date: Aug 2008 Location: Benton, Arkansas Posts: 402 Likes: 0 Liked 20 Times in 3 Posts	Re: Weldable primer Actually you shouldnt even need a weldable primer in that location, just clean it good and weld it. Primer it after. You will get a much better weld, and if its a racecar you shouldnt have rust issues there anyway if painted properly. I do alot of racecar fabrication, mostly tig, but never use a weldable primer.

12-04-2010, 10:29 PM	#6
Mark Yacavone Veteran Member Join Date: Mar 2002 Location: Miles From Nowhere Posts: 7,833 Likes: 2,927 Liked 5,143 Times in 1,964 Posts	Re: Weldable primer I 've used that stuff on floorboard patches,etc at the overlap ,where it does work well. It'll kinda melt away from the tack weld ,but still have a coating in place when you're done. I agree with others...You really don't need it for chassis work. __________________ "We are lucky we don't get as much Government as we pay for." Will Rogers

12-06-2010, 09:08 PM	#7
Charlie Yannetti Senior Member Join Date: Jan 2005 Location: Alpine, NJ Posts: 568 Likes: 188 Liked 192 Times in 83 Posts	Re: Weldable primer I had a travelling body shop snake oil salesman sell me a can once.. I said ONCE.. tried it, put it on the shelf marked "EXPERIENCE", and never looked at it again.. follow the advice on this forum.. clean it good, weld it once, paint it right, never do it again..