So, I'm about to start doing some extensive rust repairs on my car. Some of the areas include lower front fenders (patch panels), floor boards, trunk, and cowl/dash.

What I'm wondering is, would you recommend doing butt welds on everything, or can I use clecos for certain things as it doesn't really matter (such as the trunk or floorboards)?

I guess my car is going to be a driver, but with that said, I don't want it looking completely amateur either.

So, I'm about to start doing some extensive rust repairs on my car. Some of the areas include lower front fenders (patch panels), floor boards, trunk, and cowl/dash.

What I'm wondering is, would you recommend doing butt welds on everything, or can I use clecos for certain things as it doesn't really matter (such as the trunk or floorboards)?

I guess my car is going to be a driver, but with that said, I don't want it looking completely amateur either.

I would butt weld everything.

On the places that are visible from underneath of the car:

Weld, metal finish both sides, prime,block,add a small amount of filler if needed, block and sand just like you would the exterior painted surfaces.

Its undetectable, and will look great.

Thanks Bob. I was thinking of getting a set of clecos, but wasn't sure if it was worth my money. Personally, I'd rather have everything butt welded, because as you said, if done well, it's undetectable.

Yeah, alot of guys like the Clecos. I have a set, and used them...once. I find that using small sheetmetal screws draws the metal together much tighter, for a better weld.If you are butt welding,the special clamps from Eastwood are a nice item. My clecos have just collected dust over the past 20 years. They are great for assembling airplanes(one of their main uses), but are pretty limited for first gen sheetmetal. Just my 2 cents.

I actually purchased a set of clamps from Eastwood, so that's good. Wish they gave you more than 4, however. Well, I guess I'll have to make due.

Harbor freight store(not online - Don't ask me) sell these much cheaper than Eastwood.

And I bought mine off ebay.

steve

I agree on the clamps from HF. I also bought the 4 from Eastwoods, with cost and shipping at around $30. I then after seeing them talked about on this forum went down to my local HF and bought 4 packs of them with 8 clamps in each pack for $4.99 a pack. They are exactly the same.
Also the little hole saw type spot weld drill bits they ( HF) sell for $2.99 are great. I bought a few and at first did not think they were any good, I always used the German flat type bit. Now after 50 holes thay are still drilling great. Also when the hole saw gets dull you unscrew the bit end and turn it over and you have a second new tip to start over. At $2.99 you can't beat it. These are all in the welding section at the local HF.

Just my 2 cents

Ray

Yeah those are pretty good... The clamps are invaluable when butt welding a long length of panel together.. Keeps it straight...

Also, see the spotweld drill bit comparo for the camaro thread...

So, I'm about to start doing some extensive rust repairs on my car. Some of the areas include lower front fenders (patch panels), floor boards, trunk, and cowl/dash.

What I'm wondering is, would you recommend doing butt welds on everything, or can I use clecos for certain things as it doesn't really matter (such as the trunk or floorboards)?

I guess my car is going to be a driver, but with that said, I don't want it looking completely amateur either.

It's funny, most of the repairs I have seen, that occurred several years ago, have mostly "lapped" the sheet metal on quarters etc. and the repairs looked really good. You could not readily tell. A lapped repair seems like it would be more rigid. Butting panels requires quite alot more time and would be more difficult. With practice I am sure it gets easier. I guess it depends what you really want and your skill level. I doubt anyone can tell the difference until they are under the car or pulling carpet up. I know some guys that lap floor pans etc and just use a fine layer of bondo along the edge that is nearly undetectable. For me function comes first. Depending on the situation, I would use either technique.

If you do lap joint welds be certain the metal surfaces are completely clean of rust and oils . Be sure to use a something like 3M Weld-thru primer to help prevent corrosion between the sandwiched layers. The corrosion is one of the big reasons people don't like lap welds on body panels.
I had never welded before my current project and spent some time reading and practice welding and then mostly welded areas that wouldn't be seen.....such as floor panel patches and spot welds to get better . You'll be fine. Just read all you can on this forum under Basics of basics, etc before you light it up. Good luck

I am not an expert, but it seems any weld with some porosity in it would be subject to a start of corrosion.

Depends what type of welding you are doing. I prefer small tip GAS compared to MIG. I can butt joint a seam with gas but prefer to overlap about 1/16" to 1/8" so there is material there to puddle the seam together with the end of the rod.

Gas does tend to warp the surrounding surfaces but if you take you time stitching and use wet rags to you can eliminate most of it. I've always had porisity issues with MIG welds and have to grind and redo seams much more so then with GAS.

I guess it depends what you're best at doing ;o)

Tom you would be surprised how easy and nice a butt weld patch panel is with patience, practice, and a grinder. The sercret is to not overheat your work area so the panel doesn't warp. To me replacing the entire panel or piece is preferable if its badly rusted and requires a majority replacment panel. If a patch panel is in order instead then butt weld first since its much cleaner repair and I have read that a proper butt weld is stronger than a plug welded overlapped panel. It is possible to do a patch panel with butt welds that even the best of eyes can't tell. Good luck on whatever you choose. :thumbsup: Jeff

I personaly think lap welding is easier and less chance for warpage.This will be a stronger weld if welded front and back...JMO...

I don't know what a cleco is,is it the tool that makes an offset on the metal edge so you can make a lap joint? That's what I used.then I use glue and glued the panels together.the glue (fuser)is stronger than the welds,won't warp,weaken the metal, and it seals.I then grind ,fill,sand ,primer edges where needed.I've glued 1/4's on ,door skins,floor pans,etc. and just tack weld at crucial points.works great,saves alot of work.Many of the cars built today alot of the panels are glued.

On the lap weld vs butt weld debate, you do both!

First thing you have to remember is your car is held together from the factory with lap and pinch welds. There isn't a butt weld on it from the factory. So if lap or pinch welds are some how inferior or something, you better dump the whole car and make one from scratch. :)

To spend the time to butt weld poorly made repro parts on the floor of a driver is just wasted time in my opinion. On the splice on the quarter that can be seen inside the trunk, yeah a butt is time well spent.

But a nice factory looking lap weld is just fine and there are VERY few people who can look at it and tell you it isn't factory if you do the repair "factory looking" like the other hundred lap welds on the car. :)

Brian

I don't know what a cleco is,is it the tool that makes an offset on the metal edge so you can make a lap joint? That's what I used.then I use glue and glued the panels together.the glue (fuser)is stronger than the welds,won't warp,weaken the metal, and it seals.I then grind ,fill,sand ,primer edges where needed.I've glued 1/4's on ,door skins,floor pans,etc. and just tack weld at crucial points.works great,saves alot of work.Many of the cars built today alot of the panels are glued.

Heres some stuff on clecos http://www.1969supersport.com/flrpn6.html

Rob

I don't know what a cleco is,is it the tool that makes an offset on the metal edge so you can make a lap joint? That's what I used.

What you are talking about is a flanger. It offsets the edge of a piece of metal so you can lay another piece over it and the edges will lay flat against one another...

Very handy....

I think a flange tool is not what it is cracked up to be either as I think it warps the metal as well.I think if you lap weld in and outside grind and skim with plastic in and out you would have to have a pretty good eye to spot this.I but welded my marker light holes but this is about the extent of but welds for me.A cleco is like a removable pop rivet.