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.

Last edited by Jim Sears; 05/04/2017 3:15 PM.