The Stovebolt Site Forums The Shop Area Paint and Body Shop Patch panel and cab corner install

I just unpacked my welder and I got these great panel clamps that I ordered. At some point I'll order the cab corners and patch panels to start. My question is, how do you measure them out to cut? I've seen where people place the new panel over the old and use a Sharpie to mark out the lines. I assume you cut on the scrap side of the line. What thickness of cutting whell do you use? Have a .040 wheel. I'm going to practice first. I've got plenty of scrap. Input please!

When I cut out old stuff to replace with a patch panel I outlined the patch with a sharpie than on the frist cut ,cut it maybe a 1/2 inch below the line , one trick is to get the patch to fit tighter and have a closer fit so you want to make the final cut "mark" as close to the new panel fit as it will be when your done .

that cut off wheel is fine

Practice is the key and common scense

Pete

It is not as simple as marking and cutting. The initial cut is simply that, but I cut it a little lower the actual line will be. I use a nibbler where I can to prevent distortion from heat. I make a jig to get a reference for the bottom of the corner panel. I then remove as much metal as needed to get the proper fit and gap to weld. The little clamps are nifty, but they are not a fix all. The patch panels are not always the same contour as as the parent metal. You will want to weld in small stitches to prevent warping. Quite often you will have to bend the metal a little between the stitches to be a proper match. Time you spend aligning the two pieces will greatly reduce the amount of grinding later on. Practice a lot on some junk first. Weld 2 curved pieces together and then grind and then lay a something over the splice with the same curvature. With practice and patience, you can make a patch you can be proud of.

Thanks for the ideas. I'll probably wind up winging it on the cuts a little more because the cab corners are so rusted that the have collapsed. The cab was on the ground when I bought it. I have abit to drill out some of the spotwelds. It's a 3/8 spotweld cutter. I think it may be a little big. Do you use the cutters?

Has anybody ever heard of leaving the inner cab corner out? I saw an article on a old truck magazine website that said they had left them out. If so, is there some type of patch that would go in to fill the odd shaped hole so you don't have to listen to the road go by?

I wouldn't leave the inner corner out. They all go together to form a strong structure. You will want the cab sitting exactly as it will be on the truck so that it isn't distorted. I always try and use only as mutch of the patch as needed. If you mees up and have to do another fitting, you can buy a new patch but not a new cab.

I take a different approach. I only use as much of the patch metal as I have to, as others have stated. Then I work the patch metal to have the same contours as the body, next hold the patch in place and mark the outer edge. Cut the body about 1/2" shy of the mark. At this point using clecos I attach the panel along the very edge. Using a end post grinder and a cut off wheel I start cutting through both the patch and the truck removing clecos and tacking as I go. You must be carefull to get the metal in the same plane as you advance. I stay about three inches behind the cut. After all the cutting and tacking is complete I skip around mig welding the seam and the cleco holes until it's all one piece. Grind the welds and more times than not, the resulting fit up requires no filler

KC I would love to see a video of that technique.

Here are some pictures of mine when I did it. I Tig welded mine in but KC in NH's procedure is basically how I did it.

http://community.webshots.com/photo/2373924850102454676QqDeNK

Super pictures Brad

Wow, if I can get my welds looking half that good I'll consider it a good job. I guess I'll get started on my practice scrap! I'm going to put the cab on the frame. I have a 1958 cab but someparts are shot. Fortunately, the 55 cab is only beyond repair on the bottom part so I can combine the two and have a good truck once I get the spot weld cutting and the welding thing down. I'm taking the 1955 cab apart slowly. I'm pretty meticulous when it comes to getting stuff to line up. The first welds will probably take me a while so I can make sure I get it right.

Doug, here's what I started with.
Cab corners/or lack of!

You can use the link to follow through the process.(Not sure if they help)
I didn't use the whole panels,but only what was needed.
Especially the left one,thankfully i only needed a small section.

I think they'll help alright. I need the examples. Short of someone doing one in front of me the pics are the next best thing. Did you use an epoxy primer after grinding?

I just used a rattle can 'High build' primer.
Incidentally,I don't pay that much for a can!
This was just to keep the flash rust away.
I plan to sand it all back to bare metal before the paint job anyway.

I plan the same. Both of the cabs I have are pitted. I know that epoxy primer will fill the pits and block sanding will smooth it out. I really want to get started on the truck as soon as possible.

Jock, after tack welding into place did you go back and fill the rest with the welder or with other filler material? Thanks.

I just took pics of the initial tacking, but went on to completely weld the seam,skipping around to avoid heat build up and/or warpage.
I then 'dressed the weld with a 40grit 'soft' disc,again skipping around and finally a thin skim of bondo.
My metal working skills don't quite stretch to planishing and metal finishing yet!
Above all else be patient,and take time with the welding.

I didn't see any mention of this, but you will most always cut and shape both your patch piece and your cab like someone said above, you only use as much as you need.

As for warping, I had a #(*& of a problem and the solution is generally to watch out for pre-stressed areas before you weld. after the metal heats up it goes nuts trying to relieve the stresses. Or if you let too big of an area heat up. It will warp from the expanding metal trying to go somewhere.

I've used heat sink putty, copper backing, drywall spackle, etc., and the system that's most successful for me is just to blast it with compressed air (both sides if possible) after you make a tack bead (emphasis on the tack).

I'll keep that in mind. Maybe a can of compressed air? I don't have an air compressor.

No compressor? you better get yourself down to harbor freight and get one. Probably one of the most important tools.

Just happens to be a harbor freight less than 10 miles away!

Doug...I also left a pretty good picture trail how I did mine. I used a hand seamer on the new corner patches though.

Did you have the cab sand blasted and primered before replacing the parts? I have some surface rust on the cab in areas that were primered before I got the cab. I also have to replace the inner roof panel which has actual quarter sized holes from rust in it. I am taking, what appears to be a good one out of my 1955 to put in my 1958.

I used a twisted wire wheel on my die grinder. I took everything down to bare metal. Whenever I finished an area, I sprayed it with some primer to protect it. I had to replace my inner and outer cab corner. If you're planning on doing the same, do the inner first then the outer. I drilled holes and attached everything first with sheet metal screws before welding. Keep the screws in and put a couple of tack welds on the piece. If everything stills looks good and aligned, then use a couple of stitch welds. Run a 1/2"-1' weld @ every 6" to prevent warping. I let each stitch weld cool for about 2 minutes before going to the next weld. Continue stitch welding until complete. Then remove the screws and tack fill with weld. I didn't use a grinder to smooth out the welds afterwards. I used a sand paper flap disc on my die grinder. Hoped this helped. Have fun!

I figured I would use screws. It makes a lot of sense to me since you're welding anyway. I do have the sandpaper flap disk. Someone told me that's what they used so that's what I bought.