Bob, I agree with most of your comments...to a point. This area would be best repaired by pulling it off another truck.....if you could find one. In looking at what we can see of John's truck, the rest looks rather solid. If we were to find a cab in a salvage yard or field, and this area is solid enough to use as a donor, then that truck likely would be solid enough to be better used in putting it back on the road, not as a parts truck. Repops? Most of the metal bending I do is because they either don't make the part or they do and it is absolute junk. If a how-to post like this does help someone with a bit of mechanical ability to fabricate their own parts succesfully, then this post was a success. But it has been my experience that someone without the mechanical ability typically knows their limitations, and seeing a post like this will only serve to show them that all hope is not lost, the part can be fixed, correctly (with metal), don't take it to the crusher yet. I'd rather see someone perform such a repair than have rust holes slopped full of bondo any day. I know I did a guess-timate on the radius, but with a removed windshield, someone could easily form a pattern to make an exact duplicate of the opening, and by forming an MDF hammerform pattern, could even do a real nice job of duplicating the slight depression where the w/s rubber lays just below the surface. This stuff isn't that hard at all, and I purposely used basic hand tools to demonstrate that.

 

Thank you for posting the guide Mr. MP&C.
I have similar issues as john fin described. I really didn't want to glob epoxy or plastic around the windshield but I haven't formed sheet metal in years.
My uncle was the tin bender in our family, but he passed away years ago.

 

One other tip: When building a repair piece like this where you'll be joining multiple sections along a seam that doesn't exist in the original piece, if you do your welding from the back or inside rather than from the face side you'll save yourself a lot of tedious clean up and grinding/thinning of the weld bead since it won't be seen it can be left as welded. The face clean-up of the seam will then be minor sanding away of the penetration bumps.

 

Just go to your local metals supplier or even the DIY store (convenient for carrying smaller pieces but a lot more expensive per sq ft) and buy a piece of cold rolled (distinguishable by it's silver colored surface. Hot rolled has a grey/black surface and is a lot harder to work with for forming and welding) 20 ga. steel sheet. Check around for fab shops that might use it as well (don't buy thin galvanized steel from a heating duct fabricator tho)
and see if you might buy some of their drops (leftovers after cutting out whatever they are making). They will sometimes have pretty good sized pieces they consider scrap that they will sell cheap or may even give you if you tell them it's for practicing with your new welder. And have at it. You will never be able to do anything if you don't try! Even if you end up cutting and bending 20.00 worth of metal from the DIY store for practice you should be able to make at least some repair pieces yourself afterwards. If you find out you just can't get the metal to cooperate for fancy exposed pieces there is usually some uderstructure that will need replacement if the outer pieces are rust thru. Then buy ready made patch panels if available or have someone like MP&C form them for you if not. Body filler or fiberglass is not meant to be used for filling rust holes, and if used that way will soon fail and make you sorry you did.

 

MP&C,

I know exactly how you feel, I've never bought a patch panel, made them all myself for two reasons, I'm cheap and I really like working with the metal. I brought some really bad pieces of junk back to life just because I could. Here's an example:

I bought this front clip for $30, it was in pretty bad shape but it's old sheet metal and I hate throwing old sheet metal out







I had to reconstruct and replace about 25% of the metal. I took the opportunity to get my sons involved in helping replace the metal. My oldest son was genuinely amazed that I could shape and form the metal pieces to fit. I had them do most of the welding, some weren't very pretty but then we did them over to improve them.

We used all basic had tools and a torch to form the pieces. I don't have any fancy stretchers or rollers. The advice I try to offer on the board is from a guy who is working out of his garage on a limited budget. I won't buy a tool unless I can justify it for future use on other projects. I just can't afford to blow money on something I'll only use one or twice.

I didn't post my reply to rebut your post, it's a great post, I just wanted a person to think about the difficulties they can encounter in working in a area like this, especially if they don't have any experience in doing metal work. You can get away with less than perfect work on a door or cab corner when the precision isn't as important but in the widow corner you can run into more problems than most anywhere else on a body. As I stated I worked in a truck body shop for some years. One of the most difficult repairs I had to do was repair the area under a windshield in a COE Mack delivery truck. The truck hit something dead center and pushed the sheet metal in about 6". I replaced the damaged area with a factory replacement part but had a heck of a time getting the windshield to seat correctly. I took measurements and checked the curvature of the piece but had to have the window guy come in twice because the first time the sheet metal wasn't just right. It was a real pain. I can imagine if that corner of John's window isn't almost perfect there is going to problems installing the window and once it's installed there is a good chance it would leak. I just figure he could eliminate these problems buy using a donor piece. I'm sure if he would look around or place an ad on this site he would be able to find a junk cab with a good donor piece. I thought I had a couple of dash boards I cut out of parts trucks that had enough of the piece he needn't but what I have wouldn't be enough. Craigslist and eBay are good places to look also.

Good post, I like every one else, can get a lot of inspiration and knowledge from the board members.

 

Bob, kudo's for getting your boys involved in the project, I bet they have a better appreciation for the prep work that goes in when they see all the nice paint jobs at shows now....

FWIW, I didn't really feel you were rebutting my post, perhaps my response came off as a bit defensive, sorry. I appreciate your feedback, as varying perspectives are always good to get out in the open for the OP to make up their mind which direction to proceed from there.

I think all of us start out with little to work with (both tooling and the condition of our projects ) so my main intent was to show what could actually be done with limited resources, without having to run out and buy the shrinker/stretchers. Sometimes it's just as easy to break out the simple stuff and form something up. In looking at what you and the boys have done with that front end, I think you'd have experienced better results on the winshield of the Mack, the first time out, had it not been pushed in 6". I guess that's the perspective part of my response was coming from. As nice and straight as the w/s in question is, it should be a fairly simple fabrication, if someone has those skills. But I also think with everything that has been covered in this thread, and considering the welding that will be required, someone should know before starting if this repair is out of their reach. If that be the case, perhaps we've shown enough for someone to be well informed in seeking out local sources to help them along.