The Stovebolt Site Forums The Shop Area Paint and Body Shop 5 Window cab conversion

Turning a 3 window into a 5 window.
As mentioned in the Big Bolts, in the process of building a '51 COE (chassis off restomod) a 51 5 window (badly rusted) cab is being replaced by a 3 window late '49. But the client (and I) liked the look of the 5 window.
The cab is back from media blasting and the conversion is under way.
The inner cab panel was removed before blasting. Cut around the window and across the lower brace about 1/2" away from the seam with an air nibbler, and up behind the door frames a little further away.
The cross brace is going to be replaced so no need for cutting out all those spot welds and 3/4 of the rear window opening is also being replaced by the new panel so again no reason to cut spot welds.
The spot welds along the door frames were all cut out and the metal removed. Note; this will be much easier on earlier cabs that don't have welded on windlace tracks.
Wit the cab back, kraft paper patterns were made from the replacement panel to locate the cuts between the rear window opening and door frame. It is a compound curve and a bit tricky. After marking the roof was cut off 1/2" away from the marked lines and as close to the bottom seam as possible. The vertical cuts by the door frames had to have more clearance so as not to cut the flanges on the door frames.
It is now much easier to remove the hundreds of spot welds remaining (as well as the 4 bolts holding the cross brace in place).
So far all of the welds on the rear lower seam have been removed. Pics show the progress so far,

http://s1276.photobucket.com/user/jsdesign2/library/51%20ceo

Will keep updating as the rest comes off.

Shouldn't this be in the Paint & Body Forum?

That being said, I have assisted in such a project and it was well worth the effort.🛠

There is an easier way, as you describe there is a lot of cutting and compound curve work cutting those major panels and then the extensive welding.
Start with these from a donor (reciprocating saw, junkyard cut, leaving extra meat):
https://www.flickr.com/photos/advance-design_parts_co/8129371322/in/album-72157631868452754/
Finished sides look like this and don't hit any structure or alignment issues.
https://www.flickr.com/photos/advance-design_parts_co/19284317059/in/album-72157631868452754/
https://www.flickr.com/photos/advance-design_parts_co/18849820823/in/album-72157631868452754/
I used to sell these on eBay from parts trucks, I can provide instructions and more pictures if interested parties email me. It is a lot of work Jim but I am sure it will be perfect when completed.

Brad, that was what I originally considered doing. Not with donor parts, because junkyards here in the Northeast have been reduced to part and scrap operations over the last few decades.
I was planing to buy new repro panels and cut the corners out and weld them in.
However when I got the panels and looked at the construction, It occurred to me that replacing the complete panels required less actual welding (butt or overlap) than doing the corners. The only linear welds are the outside top joint from the back window to door post. Everything else is spot welded seams. In my opinion, easy to locate, clamp and spot.
As I said, just my opinion and everybody has their favorite type of welding.

Have removed the spot welded edges around the door frames, the seam at the top of the back rear panel, and the rear cross brace.
Just a lot of grunt work cutting spot welds. Using simple HSS cutters, I find the brad point is where most of the resistance is, so drilling a 1/16 or 3/32 hole through the weld first cuts the cutting time by two thirds.
Most of the metal under the welds has surface rust since none of this was painted at the factory. Cleaning all surfaces down to bare metal and covering with weld through primer. Only removed enough welds on the upper windlace and rain gutter to move them out of the way of the work.
One last piece to remove over the inside of the rear window, then it's ready for final trimming on the roof to fit the outside rear window patch panel.
http://s1276.photobucket.com/user/jsdesign2/library/51%20ceo
Sorry for subjecting you to Photobucket.

Hey Jim, I'm curious as to how traumatic it was for you to make the first cut in that perfect 3 window cab.
Carl

It was pretty tough. Took a couple days to work up to it.
Finally looked at the corner glass on the bench, remembered how nice the 5 window cab looked on that chassis and sliced in with the cut off wheel. It didn't scream or anything.

I figured as much. I went through the same thing when I cut the area out of a perfect rear fender and flip it around and weld it back in for the side spare tire carrier.

Back to work on it.
Realized there would never be a better time to make good solid anchors for the shoulder harness top mounting bolt. Much better than just drilling a hole and lowering the little kit piece down with a string.
Question: There is a hole (aprox 5/16)in the door frame below the top rear corner, and a matching cut out on the new inner panel and a gap in the windlace track.
What is it for? I don't remember anything in it and think it was covered by the windlace. Don't want to cover something up or forget something.
Could be the perfect place for the mount (was thinking an inch higher).
Also realized that I can install Dynamat on the roof and rear panel before I weld the inner panel in.

Lacking any answers and finding 2 more in the same location on the "A" pillars I assume they were used in the assembly process for alignment or welding jigs.

Sorry I haven't posted the rest of the project. Dealing with Photo Bucket is just so much crap, I'm looking for another site. Wish we could post direct like some of the antique Tractor forums I use.
It's all together and looks great. It was a very interesting project and I did some rethinks about the best ways to do each of the individual joints. Also will have more of the usual comments about Chinese replacement parts after dealing with the interior replacement panel.
I'll post more information shortly if I don't get a better way to post all the pics.

I read where they are working on a solution to the picture posting issue. Someone else may chime in on this but i believe the current infrastructure doesn't support direct posting of pics.

Flikr is pretty good, easy albums, editing and posting.

Project is on hold waiting for final decision on the new engine and other issues.
A good time to clean up the shop a bit by selling off surplus 2 ton parts. I will start posting in the parts forum.
Huck brake assemblies, transmissions (w/and wo/ parking brake assys) and more.