Welding Tips: Floorpan Lap and Butt Welds

[@never2late454]

That's how it is supposed to be done.This man definitely knows his stuff . Great video thanks for taking the time to produce it.

[@Gidjoiner]

This is the main video i used to patch up my van chassis that had to have the welds continuous , it worked well, after tacking 4-5 pushed spot welds filled the gaps & gave a good looking seam , Thanks 👍

[@johnmccarthy2268]

Fantastic video - I'm about to start welding in some new pieces in my rotted floorpans. Thanks very much, I wish you were my neighbor!

[@jmyers9853]

your welds are better than most, you understand the process.

[@johncooper7242]

thanks Craig. Video tutorials like yours give us novices the confidence to tackle these projects ourselves. Its very satisfying to know that you've done this work yourself on your own vehicle.

[@Shane-Singleton]

I was about to comment the same. I've never electrically welded a thing in my life but I'd be willing to give it a try based on what i've seen on this channel.

[@edlingja1]

Yeah, same here. I have been a real good watcher, but I see the sort of stuff he did here and say, "fk yeah I can figure that out now". You see his obvious parent-like training instincts shine through. Comments on the: wire feed, time taken to actually lay a bead, cooling, etc make it extremely great training.

[@cooneycreek8668]

Thanks. I've been watching several "quote" how-to MIG weld videos and yours is the first that actually shows you pulling the trigger before the weld starts.

[@MagaRickn]

Can't wait to get started on the drivers floor pan on my 56 Chevy. Got a brand new multipurpose wire welder, and a son that is a welder! ;) But plan on doing most of the welding myself.

[@Topper-gf8xl]

Thanks for the video and tips. Your video makes it look simple and fun. I'm new to welding with a little Lincoln 100 Weldpak flux core. I hope it's good enough to do the floor pans on my Studebaker.

[@hudsonriverlee]

Awesome detailed explanation. There is hope for my floor pan repair in my 2000 Chevy 2500.

[@hw8621]

You are a fantastic teacher Craig! I wish we had you as our instructor in autoshop 101 many students would have gotten A's instead of flunking out. Thank you for the instructive video your's is different because of the subject. Most how to welding videos even the really good ones by fantastic welder instructors are just welding pieces of metal together. Welding thin sheet metal during a restoration or customization is a must but not many videos show automotive welding work.

[@mightymoe4u2]

Thank you for showing people how to weld this. I like the cool down method.i do this stuff all the time and still watch videos to see if anyone does it the same or even if i can lure a new way to do the same job.

[@guy3749]

Great video thanks for taking the time to show us this, very helpful. Have a great day.

[@ijustloveitwhynot3805]

You 'll make America great again. Nice job.

[@bobbuilder8707]

These are great welding tips and I can't wait to try them out with my everlast welder.

[@65mustangryan]

Very nice welds. Excellent video!

[@RipRoaringGarage]

Im not sure if you guys will see this, since the vid is older, but I need some advice. Im not a welder...at all. I have a stick welder, and have welded once (succefully) but it was a thick bracket. Im working on floor pans, and other patch work on sheet metal (Ranchero woes). Do I have to do a weld completely around the perimeter, or will spot welds and tacks be enough with loads of seal sealer? I know stick isnt ideal, so Im running around 70A on 1/16 rod, and I did have some success with some patches. The patches though are much thicker, so I dont blow through the parent metal (since its already worn down from rust). I just was scared of blowing through, and kept it at some continuous welds and some tacks, and the said sealer. I will also paint on top, possibly with POR15 or a bedliner type coat. I also have to fab up the ENTIRE floarboard (mine was rotted to where nothing, not even the crossmembers were left...as I said, Ranchero woes). I will use 10ga (I know...thick but that should weld easier). I will not go for a factory look, but it has to hold weird. I plan on fabbing some square profile tubing to act as cross members, most likely along the inside to prevent dirty and rust from popping up. This car is my latest car...and Im not that attached to it (yet...), but its not bad on the outside. Inside though...its like me. I have a broken neck and lower back, with plates and bolts and fusions...so, in a way, Im getting this car back as proof that were both not down and out. (I also have the car I had my wrech in...and I will restore that one too, one way or another but at least no welding on that job! I was able to score a parts car with everything I need). I will be uploading tomorrow the video I did of what Ive done, and I dont care for views, but if anyone that knows welding, could take a look at it (it will be something with EP 96 in it...my latest vids have been...odd), but I would like to know not how good but, how bad is what Ive done. If its not totally terrible, Id be happy, and just strive to get better each time I weld. I am actually a certified mechanic (on Boeing 707 and variants, and McDonnel Douglas DC-10 and variants...but I have done loads of mechanical work to where I consider myself an expert on early 70s Continentals...I just never did anything like this, the welding, even painting...and I have three and a half cars that need my attention! I also like to motivate younger guys, that its never to late to learn and to try at least...and to not be afraid to ask for help!). I hope this wasnt too long. Loved the video and technique! That car looks like it will be (or already is by now) a gorgeous automobile.

[@ClassicCarRestorationClub]

Great question! The ‘Ask an Expert’ section is currently for members of our online community. I would be happy to send your question off to the experts. To get started, please send the email associated with your paid membership account. Thanks!

[@accordfreak1]

great video! why mig as opposed to tig?

[@ClassicCarRestorationClub]

Hello, Thank you for contacting us. Great question! The ‘Ask an Expert’ section is currently for members of our online community. By becoming a member, you will have access to our expert’s knowledge in classic cars. With your membership you will also receive discounts on products and hours of Premium video content. If you are interested in becoming a member to the Classic Car Restoration Club, please click on the special offer below: www.classiccarrestorationclub.com/?add-to-cart-multi=1&products=618&skipcart=1&coupon=C24047&CCRC&Email&.59&C24047&vscid=C24047 If you have any further questions, please chat, email, or contact Customer Service at 1-855-706-3534.

[@scottmiller6771]

Very good video as I need to patch a rusty floor. My question, not knowing anything about welding, why do you weld pushing away instead of starting at a point where you would weld pulling towards yourself?

[@drew2truth]

I am currently replacing floors in my truck, i have to lap weld a few spot and wondering what primer you are using to weld onto? I'm worried about contamination and want to eliminate any chances of it later on after all this work, thankyou for your videos

[@ClassicCarRestorationClub]

Great question! The ‘Ask an Expert’ section is currently for members of our online community. I would be happy to send your question off to the experts. To get started, please send the email associated with your paid membership account. Thanks!

[@drew2truth]

@@ClassicCarRestorationClub no thanks we are in lockdown gotta pay bills before i pay a membership for my question when I found my answer through Google research fairly quick and easy.

[@youngestson6537]

Very informative. Great video.

[@youngbuckrestoration3912]

These are great tips to know, and I don't even have a project car to put them to use haha. One question though, is the rapid cooling with the air nozzle a way of preventing the sheet metal from warping?

[@ClassicCarRestorationClub]

Hi Matt, Yes the reason for the air is to eliminate heat buildup in the sheet metal. Heat buildup can lead to warping the sheet metal, and when working with sheet metal much of the effort it spent controlling warpage. Mark Classic Car Restoration Club

[@351kostakis]

Fantastic

[@ClassicCarRestorationClub]

Thanks so much!

[@silverious1le299]

What gas is best to use for mig welding?

[@ClassicCarRestorationClub]

Great question! The ‘Ask an Expert’ section is currently for members of our online community. By becoming a member, you will have access to our expert’s knowledge. With your membership you will also receive discounts on products and hundreds of hours of Premium content. If you are interested in becoming a member, please click on the offer below: go.classiccarrestorationclub.com/a19769 Thanks!

[@kawasakiklx1]

Thanks for this! What is that cab painted with and how durable is it?

[@yeoldepirate783]

Hello, If you are fitting up and calling these "lap welds" is the sheet metal lapped over? what keeps the moisture out on the underside? thanks I have a big resto project and this will be very helpful

[@ClassicCarRestorationClub]

Lap welds are the best for floors and firewalls, but you are correct unless they are sealed up. it only gives rust a place to grow.Always apply "Seam Sealer" to lap welds If you look closely at untouched factory seams you'll always find one side or both have seam sealer applied.I prefer a good quality "Autobody Seam Sealers" that are paintable. Here is a link to one good source: ( www.autobodytoolmart.com/3m-urethane-seam-sealer-p-19154.aspx )I always do both sides of the seams, and apply it liberally, it looks weird right after it's applied, but once it's primed and painted it nearly disappears and provides the protection you need.

[@raymonroe1983]

Those are nice welds.

[@chrisorazio925]

How do I make the rust not come back? Lol...getting a wheel well repaired with new metal and people keep saying the rust will come back. Esp at the weld spot in future because water will somehow get in...really bummed about this because I just got the car smh.. can I Plasti dip over the repair to ensure no water ever comes into contact with the weld repair again? Lol. Best options to make sure the wheel well doesn't rust again at the weld spot ? Thanks for any replies. Need some optimism lol. Going to be paying $800 for a wheel well repair ( cut out old metal and weld in new )

[@ClassicCarRestorationClub]

Zinc rich weld through primers go a long way toward slowing down rust. Keeping moisture out of the seam also helps, like using seam sealers. About the only way you can guarantee not ever having rust problems again is to not drive it, and store it in a climate controlled well ventilated room. But what fun is that. A good repair on a daily driver will last 5-10 in harsh climates, on a show car driven primarily driven in good weather, it can easily last the life of the owner.

[@stevencobraR]

This may not get a reply, but should I leave the sheet metal screws in? Or do I weld up the hole left behind?

[@ClassicCarRestorationClub]

Hello Steven, The screws should be removed and the holes left behind can be filled wit a simple tack weld. Hope this helps, Mark Classic Car Restoration Club Video Membership

[@jeffreylonigro1382]

Use Clekos and just fill in the 1/8” holes with welder. It’s better than clamps

[@whatwasithinking8159]

Hi, when you use the screws to pull the sheet metal together, do you weld over the holes afterward? Thanks for the great video!

[@tiredowalkin]

I was wondering the same thing, and he did not comment in the video or here. I surely would after having a nice weld to hold it together, it only makes sense to back out the screw and fill up the hole with the welder while you are there.

[@67cudaksa34]

you get a device known as a copper spoon. you put it behind the hole and fill it with a weld/ Mig welds will not stick to copper

[@d.slater3958]

Great tip. I hope to save enough to buy an everlast mig welder at some point and have always wondered how people are able to weld thin metal without burning through.

[@67cudaksa34]

i make my spoons out of short length of copper pipe, i flatten it out and then bend it to the proper angle. if you are by yourself. use a bottle jack under the car as a third hand

[@Mitchumthegreat]

Awesome. Helped me.

[@marcinklukowski1774]

What helmet do you use, the response time is what I'm looking to buy. Was totally impressed. Like your video too!

[@ClassicCarRestorationClub]

Craig is a big fan of the Lincoln Electric welders and accessories. His helmet used in this video was the Lincoln/Viking series 3350, and he also frequently uses a series 2450 helmet often too.

[@djstatyk1540]

Question: What size wire are you using? What speed? i'm using a flux core welder i got from harbor freight, it seems to work, but i'm no professional. Just a kid trying to make the best of what he's got.

[@andop82]

Hey mate. Im a welder by trade for 15 years now. Use solid wire and gas .9mm is about as big as you want to go. I'm using .6mm for panel work like this. Hope this helps.

[@ClassicCarRestorationClub]

Hi DJ, While I do not recommend using a flux-core welder for sheet metal; I do understand making what you have get the job done. Use the smallest diameter flux-core wire that will work with your welder. The wire speed will be determined by your heat range, experiment a little and you'll find setting that give you predictable results. With flux-core wire you'll get more weld splatter and it will burn a little hotter, so take your time and skip or stitch weld your seams, and cool things down between short welds to avoid building up heat and warping sheet your sheet metal. There is no substitute for hands-on learning, so take your time, learn from your mistakes and remember all die-hard car guys started where you are, so enjoy the process. Mark Classic Car Restoration Club

[@tobywhitaker4246]

a cool wet rag work good for cooling " reduce warpage" , and a pinch bar works good for pushing down Un clamp able areas.

[@roberthayes5037]

Outstanding 👍👍

[@callofgeorge]

what size wire are you using to be able to weld as constant as you are on sheet metal? im running .025 and i can only put a dot before waiting to cool. i dot, skip 3-5", dot again. then go back and overlap to fill the seem.

[@ClassicCarRestorationClub]

MIG welding sheet metal is more difficult than many make it.Burn through, controlling heat buildup, gun speed, wire speed, heat settings, etc... all affect the quality of the weld.We typically use .023 wire on sheet metal, but also use .030 wire as well. Your .025 wire should work well.Consider turning down your welders heat setting and/or increasing your gun travel speed.In some thin metal situations you may have better luck placing a scrap piece of 1/16-inch copper behind the area to be welded. It will prevent burn through and the copper will not bond to the steel (it may stick sometimes, but can easily pulled off). This is also a great way to fill small holes too. here's a link to a tool for this: www.eastwood.com/welders-helper.htmlThe best advice is to practice on an old fender or similar, and find a technique that works best for you.

[@robstone661]

hi there,are you using flux core wire or gas shielding ? great video

[@ClassicCarRestorationClub]

Rob, we prefer to use a shielding gas, as there is less splatter, cleaner looking welds, less slag to grind off and it welds a little cooler. Which is a good thing on sheet metal where you are trying to control the amount of heat created to prevent warping the sheet metal.

[@MyChevelleSS396]

Hi Craig, Could you let us know what size MIG wire you use and at what voltage the welder set.

[@ClassicCarRestorationClub]

When MIG welding sheet metal, thin wire is better. Most often .023 solid wire is used with a 25/75 argon/CO2 shielding gas. Some welders can not use .023 wire, so .030 wire can also be used instead. The voltage setting is different on every welder and welding condition, just make certain you are getting good weld penetration without burning through.

[@bharatsinhrathod8800]

Very nice

[@juniorsmk46]

Thanks for the channel guys

[@carlosextromolo3753]

I'd love to see how an everlast pulse mig welder would work out on sheet metal.

[@bigwillypacino711]

Can I use flux core for welding in my floor

[@npa4863]

I wouldn't use fluxs core on that because it burns hotter (youll burn thru the sheet metal alot) and its very splattery so clean up and or fire Hazzards may be an issue...

[@npa4863]

You can get a shorty tank filled for about $60. The welding supply shop i go to lets you lease the cylinders about $50 a year

[@bigwillypacino711]

npa4863 thanks I just bought a tank today it cost $290 Canadian paso's and its the small tank but it $70 to fill it up

[@npa4863]

Bigwilly Pacino yah currency difference put it up alittle more

[@tiredowalkin]

Flux core wire welding (mig) will leave some slag on your welds, and although not pretty, it's ok, and if you decide to get a tank with C02 and Argon mix (shielding gas) and a regulator and convert your welder, make sure that you school yourself about the welder polarity. I did not change the polarity ( switching the leads) when I added the gas feature and my welds were sloppy and ugly.

[@svs8909]

i use zip screws to hold panels

[@axa.axa.]

Wouldn't blowing air on molten metal promote porosity

[@ClassicCarRestorationClub]

Hi Axa Axa, Not necessarily, rapid cooling will harden the weld some but when working with sheet metal the larger concern is heat build up and metal warping. Cooling the weld is a great way to eliminate heat build up which will prevent warping. Keep the welds small on sheet metal and control the heat. Mark Classic Car Restoration Club

[@iainmaclean4872]

MIG welds cool off really fast, and dont stay molten for very long. Now, if i had someone blowing oxygen onto my weld while i was welding, the'd get slugged right in the mouth

[@brianbreit]

fine work

[@TheBeardedJeeper]

What do you use for the helmet cam

[@ClassicCarRestorationClub]

For most of our video clips we do not use hemet cams, but rather a Sony full professional camera, although when shooting welding videos we often use a #10 gold welding lens over the front of the lens. We find we have more control over image composition if we have a camera man dedicated to getting the "shot". There are times when we do need to get cameras into tight spaces and have used Sony Action Cam Mini's and GoPro's.

[@christiantaylor6867]

Now..,when your done with that lap weld would you be putting some seam sealer over the seam???

[@npa4863]

Dosent blowing the welds blow the sheilding gas away?

[@ClassicCarRestorationClub]

Using an air blow gun to cool the welds is a way of controlling the amount of heat introduced into the sheet metal and prevent warping. Most MIG welders have no post flow gas supply so the shielding gas dissipates as soon as the welding stops. When welding sheet metal warpage is often more of a concern than welds cooling in an inert environment. Great question though!

[@jvmiller1995]

You would think someone making a DVD instructional how to weld video would talk about prep work. Mig is a clean process tig even more so. Why would you not sand the red primer/paint off. Especially on 18 gage or thinner metal. You will end up having to throw more heat at to burn the paint back. Now I realize it is a non critical weld and the burned paint in the weld puddle will not hurt the weld. But on this thin sheet metal it makes it a lot easier to burn through all the way through or to warp the panel. The bad part is you are teaching these people and they commenting about learning to weld and that you make it look easy. 90% or welding is clean prep and positioning your self to weld as much as possible with out stopping to reposition. But this is just my thoughts. Welding since 1989. Don't get me wrong sometimes if I have a little spot to weld and have done the exact same thing. But I would not teach people to take a short cut.

[@duett445]

Jeremy Miller maybe he is using weld through primer. I never used it but it available.

[@jvmiller1995]

@@duett445 never heard out it.been a welder for 20 plus on off. No auto body work. But just saying i am sure most people would not know they paint is special.. you will get some shit results with burning over regularly paint especially with mig. I was even thinking it's not really welding bad but. So thank you explains a lot

[@kennedywong9854]

From my experience in welding, you dont need an air gun to blow air on weldin bead because It will cool it self down.

[@duett445]

Kennedy Wong on thin sheet metal it is essential to cool it down quickly to avoid warping. Some use a wet rag some use compressed air some use a copper plate pice, it what works best for you.

[@cmscms123456]

sheet cleco metal clamps, look into it

[@fastsofaracing]

Snip the filler metal before you weld. my pet pev. great video though

[@metallideth503]

Actually the guy doesn’t have a clue, generally speaking you don’t want to skip weld anything. Untill it is all tacked up 100%. That goes with anything that you weld ever. This metal will move. I realize he has it clamped but it will move those clamps like they are not even there..

[@royk007]

Nice job! Most garages cant weld that thin metal car parts they fucked up! I can do that better without the welding papers ;-)

[@fanwlkr]

I know youre the expert and all, but letting it cool slowly wil lett more hydrogen escape from the welded metal, making it less brittle, it will warp less and there will be less tention in the steel

[@iROBODUDE]

Here is what I did on my 76 F100 floor pans. kzbin.info/www/bejne/bnbGpmd4bLqSo68

[@shawndoyle6460]

Push Gas , Drag Slag