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Tip of the day number ?

7057 Views 18 Replies 6 Participants Last post by  bluesman123
I hope this isn't a double post, I don't see the one I did a few minutes ago. :sweat:

“Basics of Basic” Floor welding tip
By Brian Martin

This tip isn’t only for welding in floors, it can be used anytime. But it works the best when plug welding a thin sheet metal to a thicker brace, frame or whatever. Welding trunk floors into late model cars that have been rear-ended is common practice these days. Just a light hit on the rear of most late model cars will result in a badly crumpled floor and a frame rail or two needing to be replaced. After welding in many of these cars and always having a problem with keeping the floor nice and flat against the rails while welding, I came up with this trick that really works well for me.

I used to lay the floor and align it, then mark the underside around the edges of the cross members and rails with a sharpie. Remove the floor and punch all the holes around the edges of that line I made so I could plug weld the floor to in. I have some real nice punches with a long reach and I would drill the ones I couldn’t reach. This required cleaning up the back of the holes of burs and spraying some weld thru primer and what not, a lot of prep work. But I thought I was slicker than snot doing it this way, the thing sat back in there with a row of holes all the way around right in the right place and it really looked good. Until I started welding, no matter how nice I could do a plug weld, on these floors the darn thing would always come up a little around the holes as I welded and it looked like crap once done.

The solution is not only produces a better end product, but it is much easier. What I now do is to align the floor into place. I will hold the floor in with a sheet metal screw here and there just as before (later welding the hole up) but now I put them where ever I can draw a straight line from screw to screw or at least be able to know exactly where the rail or cross member is beneath the floor. I then mark it ON TOP of the floor where the holes need to be to plug weld it in. So, I have a nice floor pan with no ecoat removed, no grinding, no drilling, just a nice new pan sitting there on top of the rails. The rails by the way were cleaned with a Maroon Roloc surface-conditioning disc and a weld thru primer was applied.

I now drill a few holes thru the floor pan and a little into the rail. I use a killer spot weld drill I get from our fastener supplier (Winzer). They cut a shallow hole so I don’t cut thru the rail, but they have a pilot tip that is like an 1/8” drill to keep it where I want it as it starts. And they drill VERY fast. They are 8mm (about 5/16”) in diameter.

Soooooo, these few holes are now drilled, I have perfectly clean metal in the rail to weld to, the metal is a little thinned by the drill so I can get good penetration with a nice fast, hot weld! I weld these welds very hot and fast leaving a super clean flat weld on the top side. PLUS, the weld is so hot and fast that the surrounding floor pan doesn’t lift up from the heat as it did before. After a few welds, I drill a few more holes and weld them up, and on and on until it is done, skipping around side to side and even walking away and doing something else now and then to let it cool off.

I use this same method on radiator supports to the frame, when ever I am welding a thin metal to a thicker one. It produces a cleaner plug weld than anything I have ever tried when welding a thin metal to a thicker one. Plus, less corrosion protection is burnt off.

Tip of the day number ??
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Hey Brian, I just want you to know..... Your articles and vast knowledge on body/paint work is impressive. I have read, and re-read, sometimes even tripple read your tips and articles......I've even forgotten some things...... and have come back months later to refresh. Sometimes remembering later that I had already read that article. :drunk: Anyhow your articles are great.

In all that you've written here on this board and others....I haven't seen any thank you's.

I just wanted to say "thank you". You make me a better body/paint man.

Thanks again, Mark from Portland Or.
Thank you so much for your kind words Mark, I really appreciate it. You may not have seen any thank yous but there have been plenty or I wouldn't keep doing it. :)

I thank you again Mark, that is very nice of you.

He knows we love him.
We beat up on him every once in a while to remind him.
Hey Brian, you have some good tips but for sure you
have the longest-LOL! Thanks man :thumbup:
Hey Jim, you notice I hit number 2500 post, wow. Yeah, I know I am a little "long winded" :) And Thank you!

I did notice that you were on 2499 and was waiting
to make some kind of smart-*** remark when you hit 2500.
Oh well too late. :)

Keep up the good work :pimp:
Nice write up Brian. Thank you.
So, Your spot bit is countersinking out the metal UNDER the new pan which would allow the weld material "some" place to go besides build between the 2 as it normally would causing the metal to rise up.
You got a pic of this spotter or link to one?
Longwinded or not, Brian, this is great stuff for amatures like me!! :thumbup:

Bee4Me said:
Nice write up Brian. Thank you.
So, Your spot bit is countersinking out the metal UNDER the new pan which would allow the weld material "some" place to go besides build between the 2 as it normally would causing the metal to rise up.
You got a pic of this spotter or link to one?
They are for sale here on ebay (click here) but I don't think they are the MONSTERS I use as mine are much more money. They are vicious cutters.

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bluesman123 said:
Longwinded or not, Brian, this is great stuff for amatures like me!! :thumbup:

You know Dave, I have read too many "how to" articles that leave out all kinds of stuff, what good is that?

I did a Camaro clip on my truck following an article in a rod magazine. So here I am reading this thing over and over before I cut the frame in half and I notice an angle finder sitting on the upper control arm shaft in some of the photos in the article. No mention of it, the thing is just sitting there. Later I am talking with a guy who had done a frame clip on his truck and he told me how he screwed up and the when he went to get it aligned they had to use "offset" upper control arm shafts to get the caster he needed. Right as he said this the lightbulb went off in my head! THAT was why they had that angle finder there!!! I got the angle of a stock Camaro and duplicated that on my truck. Now, do you think they could have mentioned that in the article????? Was that too much trouble??

No, somethings just have to be explained out.

Brian, I hope you know I was just kidding you. :D
I agree that we need things explained in as much detail as possible.
I commend you for giving enough detail, I'd never ever want to
suggest you to shorten anything. There's plenty of space here for it.
You keep up the good explanations, I have a hard time following
instructions so I'd be the last to suggest you cut back.
Thanks for being thorough enough that even I can understand.
I wish more would do the same. :thumbup:
Honestly, I find most ANY magazine or T.V. show "How To's" incomplete and you get just enough information to SCREW it up.Too many "little" details left out that cause BIG trouble far into the job.
Watching one Sat. on installing a 4 Link . THAT is something you can't do in 15 min. :spank:
The information from knowledgable people like You,Badbob,Barry,Milo,and MANY others HERE is priceless.Thanks to you guys.

Those are just self centering bits from the looks of them and I actually use those myself but they do require some "skill" to use for cutting spots else your thru the panel. By monsters, Are you saying yours are "better" or "bigger"?
They are better, I drill hole after hole abusing the hell out of these things and they just keep right on going. They are the toughest drill bits I have ever seen.

These are three for four bucks? Honestly, I forget how much ours are but I know they are quite a bit more than that. Check them out at (click here)

The site is not for the retail sale I guess, I just looked around to find the bits and this page was all I could come up with. The ones I use are part number 697.10081

To be fair to the how-to articles, it is just plain hard to explain in writing how an expert does somehting. Combine that with limits on word count and there are bound to be things left out. What we would ALL like to do would be to be looking over your shoulder while you do these things, but I guess it would get a little crowded! :D

Thanks again for all the detail you put into your tips!!

The car magazines are definately poor when explaining correct autobody proceedures-I've never read one that was even close to accurately explain the steps and materials needed to do a job right. Another magazine thing that really burns my *** is there is rarely enough credit given to the bodymen and painters who usually put in 5X the hours work compared to the wrench turner who got credit for the build. I think if the magazines did a thorough step by step from bare metal and bump work and panel fitting all the way through to paint and assembly one month at a time there would be more interest in the bodywork articles-afterall this is exactly what the doityourselfer is tackling at home.
Brian, keep posting the articles and we'll all keep reading and learning. I've used the method you described for years but never really thought of it as a technique, it was always in my mind considered a shortcut that saved me from having to punch all those holes!-sometimes in the wrong spot...
What do you think of Chrysler's latest recomendations not to use weld through coatings? If anyone wants to certify their welding skills take the I-CAR welding test, with a 40% failure rate it's not as easy as one would think. Ramble, ramble... Bob
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Bob, these manufacturers are changing their recommendations so much. What exactly is the Chrysler recommendation? Last I heard it was to drill the spot weld, then spot grind that tiny spot and then weld right on that exact same spot to not "need" weld thru coating.

There is a lot of talk about the use of weld thru, I don't know, it seems like every manufacturer has something different. Chrysler wants you to use a butt weld with backing with no weld thru coating, then Toyota wants you to butt weld the seam with no backing and to use weld thru coating on pinch welds. Who the heck knows..

Not using weld through is a problem for me and probably for others who can only do this on weekends and in the driveway. From one Saturday to the next, if I don't have something to coat the work-in-progress, I can start getting surface rust even here in the Bay Area. I guess I'll just keep on doig it and hope for the best.

Keep right on using it, it is the best way to protect in short order, period. And if you don't apply it too thick or weld while it is still wet it really works pretty good and doesn't effect the weld much. And for goodness sakes, wear a welding resperator those are zinc fumes you are creating with you burn it.

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