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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Feb 2005 Posts: 338 Shop Shark | | Shop Shark Joined: Feb 2005 Posts: 338 | I went over to see my 1940 Chevy truck cab at the blasters.
There are hundreds of tiny holes in the sheet metal. almost all in the belt line around the back of the cab. Some down low in the front corners too. I was expecting that, but not way up on the cab.
I didn't take my camera so I don't have any photos yet.
Is this area prone to rust? What is the recommended method for fixing? It doesn't seem that thin but it must be. Can you just weld up each hole or will it just blast right through. Do you have to cut out the belt line? That can't be easy to fabricate.
Man I am bummin'
Bill Schickling | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | Generally when you have pinholes, welding just produces bigger holes. With a copper backing you might have a chance but the areas will be larger than the original holes. | | | | | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | Bill,
Can you have the "other" side of the holes blasted too. In other words, the inside of the cab. Lots of little holes would be a candidate for fiberglass, and I mean cloth, resin and catalyst, on the back side and body filler on the outside. I think this could be a permanent repair if ALL of the rust around each hole were blasted to very white metal. My only concern is that the metal must be very thin in these areas. Isolated rust holes seem strange..was something behind them that trapped water/moisture.
This method sounds second class, but I think it would be effective, permanent and invisible if done properly. The absolute key would be to get rid of any signs of rust...then seal it from the atmosphere. Unless you have another cab available you are going to have to think positively.
Stuart. | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | fiberglas on steel requires a special resin that's too expensive and special order - solder'em up - butane torch and some acid core solder
Bill | | | | | Joined: May 2004 Posts: 191 Wrench Fetcher | | Wrench Fetcher Joined: May 2004 Posts: 191 | I just went through the same thing on my 42 cab. There is actually an overlap of metal there on mine. This had allowed dirt and moisture to collect over the years and rust thru from the inside out. I used Metal-2-Metal body filler and sealed the backside afterwards with paint and such. Metal-2-Metal is waterproof and has given me good results over the last few years on the Mustangs we've restored. That is what I'd recommend, since welding would be difficult at best. | | | | | Joined: Mar 2004 Posts: 31 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2004 Posts: 31 | I also had the same problem on my '39 cab. I definately agree with Clint's method. That Metal-2-Metal stuff is pretty darn hard and holds up very well against anything. I think that would be your best bet. | | | | | Joined: Feb 2005 Posts: 338 Shop Shark | | Shop Shark Joined: Feb 2005 Posts: 338 | Everyone,
Thanks for the feedback.
I did have the entire cab blasted inside and out so I asssume what is left is thin but solid. Sounds like this is common on the 39 - 46 style cab.
I guess I'll try to figure out how weak the area is before I go forward. They painted the cab after blasting with epoxy primer. So no mater what method I use I will have to get the paint back off. I like the idea of plugging the holes some how, but worry about how much grinding the metal will support. If it doesn't look good I will use the body filler method.
Is Metal-to-Metal a brand name or a type of body filler?
Bill Schickling | | | | | Joined: Apr 2004 Posts: 888 'Bolter | | 'Bolter Joined: Apr 2004 Posts: 888 | I currently got my 4t6 cab back with similiar problems, The lower front cowl under front fenders I cut out and used a panel flange and spot welded. Cab corners weren't to bad so I used mig with copper backing plate. Some holes got bigger as stated above. I am considering using a product called Lab Metal. I read some good reviews but never used. But with the long winters up here we have a lot of time
Dan | | | | | Joined: Apr 2004 Posts: 888 'Bolter | | 'Bolter Joined: Apr 2004 Posts: 888 | red58,
What is the process for soldering? Basically the same as sweating copper pipe?
Dan | | | | | Joined: May 2004 Posts: 191 Wrench Fetcher | | Wrench Fetcher Joined: May 2004 Posts: 191 | Bill:
Metal-2-Metal is an Evercoat product. You should be able to find it at most any Body Shop Supply. It has aluminum powder in the epoxy mix. BTW, the folks at the PPG Store advised using filler over the epoxy. I've done this for years with absolutely no problems. Good Luck. | | | | | Joined: Feb 2005 Posts: 338 Shop Shark | | Shop Shark Joined: Feb 2005 Posts: 338 | Chev4t6,
New Hartford - Your not too far east of me. Sounds like our cabs are in very similar shape. The front corner under the fender line and the belt line have all the damage.
One funny thing that appeared was a 1/2 inch hole and four 1/8 holes on the roof that must have been for some sort of light. It is right in the center of the roof, so it made me think of an emergency vehicle or something. I don;t know any of the previous owners so it is a mystery.
Clint,
I will look into this. I am not a welder so I either need to dive in and buy a mig welder or use a product like you describe.
Thanks,
Bill Schickling | | | | | Joined: Jan 2005 Posts: 1,682 Extreme Gabster | | Extreme Gabster Joined: Jan 2005 Posts: 1,682 | My '46 1/2 ton had a few pinholes in the same area.. back of the cab in the "beltline" area.
I saw an old school dude on American Hotrod do some body work with lead.. and I just happened to have some old lead battery terminals laying around.. so after sanding the area down to bare metal, I applied a lead patch, sanded smooth, and painted over it.
Lead ain't gunna rust or bubble.
I suspect this is simular to the solder method mentioned earlier in this thread.
an idea is only stupid if you think about it rationally.
| | | | | Joined: Dec 2002 Posts: 571 Shop Shark | | Shop Shark Joined: Dec 2002 Posts: 571 | Bill, I got the same thing on my cab roof. The PO just bondoed over the holes. I put a visor on it & covered it up till I get to it. :rolleyes: | | |
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