How To: C15a Wire-3 restoration

[Jordan Baker]

Finished rebuilding both fuel tank senders. I checked them out with the ohm meter and got decent readings. They were given a sandblasting to make the arms clean and free moving. I painted the tops in POR15 to hopefully seal out any chance of rust inside them. I picked up new floats from Mac's Antique Auto. They fit perfectly in the curved part on the arm.

[Jordan Baker]

I have finally started in on doing major body work. I removed the cab lower wall skin using a spot welding drill bit. it worked reasonably well except I found it cut into the base metal sometimes and other times it really wandered around. When I removed the skin three of the wall braces fell right out. I went down to metalsuper market today and picked up a sheet of 18ga sheet metal. They cut it all to size for me. Tomorrows task is to sandblast the frame and then begin attaching the panel. Once I get this done i will be moving onto the roof.

One aspect I am not to sure about is how to paint the backside of the frame. I would like to POR15 it but then Im worried about how to weld the skin on. If I weld the skin then POR15 everything will I get it sealed enough to stop rust formation inside the joint?

[Phil Waterman]

Hi Jordan

How do you plan weld the panel on? Pinch spot weld, or plug weld?

Either way you will need to clean down to bare metal at the weld points, if you are going to plug weld I'd lay out the panel drill holes to match the spacing on the orginal. Prep the cab frame paint with POR 15 let dry real good then mark all the weld points, spot grind all the weld points to bare steel. Be careful of the fumes from welding close to POR 15. Think you will get pretty good rust protection down in the joint.

If you are going to pinch weld then I'd go with a weld through primer on panel and cab frame. Some of the weld through primers work better than others. Best one I've found for good welding is SEM 40783 Copperweld which welds really weld with MIG or Pinch Spot no personal long term testing on rust protection. Other that I used is Martin Senour NAPA 7221 Zinc Weld Thru Primer, it doesn't weld as smoothly with MIG and it needs a light coat for good spot weld, but it does protect from rust very well. I've had test panel with just the NAPA stuff out in the rain under roof edge hanging so that it gets wet every time it rains. No rust after two years.

Hope this helps

Cheers Phil

[Bob Carriere]

Hi Jordan...
.....Hi Phil

I am at the same place as Jordan.....removed the rear skin.... replaced the bottom angle and now getting ready to do the new skin.

I am using satin coat steel in 20 gauge and will use Norton metal glue used in body shops. The angle iron frame and back braces have been sandblasted, phosphated and painted with POR 15 but left the contact area for the skin bare.

Plans are to use the Norton 90 minutes set and clamp everyting in place. The reason for using the Norton glue is that it will seal forever any gaps between the skin and the angle iron...... which we all know tends to rust after 75 years.....

We have limited but positive experience with the glue having done patches on Grant's cab 13 rusted top portion. seems to hold very well and seals very well. It has cycled in 2 Ontario Winters not sure how it will look after 75 years parked behind the barn.

We are working on top of a large steel table with a very stiff ( 5/8 SS) top. We will precurve the sheet metal with rollers and try to get as good a physical fit as possible before glueing. everything will be clamped mildly to the table top with small sand bags pressig down on the wall reinforcement brackets.

No spot welds will be used.

If that works well the door skins are next with the same process except the edges will be double glued and folded back on themselves as if spot welded. The inside of the door will be painted with POR and proper drain holes cleared up.

Body shops that I have talked to swear by it strength and ease of use. I was told that in certain designed body crush areas they regrain from overlapping the glued panels by more than 1 inch as it increses the strength too much and defeats the crush zones.

Only time will tell. will try to document with photos to be posted on the Hammond Barn site.

Now back to the POR 15 combination with spot or rosette welding...... should work if you allow sufficient room for heat travel or cool off quickly with wet rags. POR as very limited endurance to heat.

Jordan once you have done your welding consider dripping POR in whatever gap might exist....... it has a great tendency to inflitrate and move by capillary action.

For example after welding a bolt hole shut anddoing the final grind everything looked very good. I painted one side with POR and flipped the part over to paint the other side and a tiny small speck of POR actually penetrated a pin hole and totally sealed the patch.

Good luck to both of us...

...and more to come on this back wall issue.

Cheers

[Bob Carriere]

Jordan

Consider using a 3/4 plywood sheet supported by 2x4 on the side between your saw horses or get a surplus laminated door as a work surface....

Cheers

[Jordan Baker]

Thanks Phil and Bob for all the tips and suggestions. I am aiming to do the welding early next week. I love being off on holidays.

I'm thinking I will sandblast the frame and then paint with POR. Layout the new sheet and drill my holes for plug welding. Then go and mark the spots on the frame and grind those down. Once it is welded on I'll use a flap wheel to smooth out the welds. Then flow the POR along the seams to try and get it all sealed up.

Bob I've got four different work tables in my shop. I've got a metal clad bench. I was given a 4'x8' home made table with 3/4" plywood on top. I use this one for all my welding needs. Then I have a set of Cnd Tire saw horses with a piece of melamine coated desk top. And lastly another pair of Cnd Tire saw horses to use as needed. They have probably been the most useful things I've bought from Cnd Tire in a long time. Currently on sale too.

[Phil Waterman]

Hi Bob

Forgot about using adhesives I've used the 3M automotive adhesive system use on cars today to replace door skins. Not sure that it is more rust resistant than paint and welding all you have to do is look at the inside edge of 15 year old cars in the rust belt to see rust blisters in the the paint where the edge folds over on the inside.

Of course the level of rust protection it will give our CMPs that live indoors drive primarily only in the summer, I'll bet that they will not see the rust problems we are repairing now.

Back to CMPs one thing I noted on replacing body panels that are spot weld to channel iron is there is no sign of any paint so it is pretty clear that the panels were welded on bare and then painted. So what we are doing today to prevent rust will be talked about by the guys in 2115 who are restoring these trucks and wonder where the will get this stuff they called gasoline to make the trucks run.

Cheers Phil

[Barry Churcher]

[QUOTE=Jordan Baker;211939]Thanks Phil and Bob for all the tips and suggestions. I am aiming to do the welding early next week. I love being off on holidays.

Jordan, I thought you were a fireman! You mean they give you holidays as well?
Barry