Rotor, You've posed a great inquiry. I can only offer my opinion and comments which is based on quite a bit of experience.I've never done the 1939/40 running boards but I am aware that FoMoCo had the rubber vulcanized on most all of the cars after 1932 or so. The metal of the boards was originally prepped to hold or grip the rubber material better during the vulcanizing process. I was curious to those in the know of just how rough the metal is on the 39/40 models after you get all the old rubber off?
I've used a lot of different metal based fillers from Aluma-Lead to Metal 2 Metal and even Devcon plastic steel. These fillers have a difficulty factor to them that surpasses any type of normal filler material. My reason for wondering about the board texture is just to question how much filler will be needed to smooth them out. After the covers are on, the boards are fairly well water proofed and any good Rage filler or maybe Duraglass should work OK depending on how thick it is. Generally, it's the condition of the underlying metal that caused delamination of the filler materials with time. Strong changes in temperature and exposure to sun & weather also take there toll.
I used Vintique covers and contact cement. Fit like a glove and hasn't come loose in about 17 yrs.I have a set of 41 covers to install. I was thinking maybe construction adhesive would work better than contact cement. Anyone have trouble with contact cement letting loose in the hot sun?
Exact method I used. Works great.mrtexas:
Construction adhesive will not "flow out" and will leave bumps and ridges.
I Used Contac Cement , spreading it out with a Bondo spreader on both the running board and the underside of the running board. Once the cement dried to being "tacky" I placed wax paper in between the cover and the board and slowly pressed down the cover to the running board as I pulled out the wax paper. Use a roller to "push out" any air bubbles.
Or, you could apply the Contac Cement to just the lip of the cover and the curved edge of the board, let both 'Tack up" and then join the two together. This will permit you to lay the rest of the cover down on clean metal to see how the final fit will be. Then lift up on the cover, apply another coat of cement to a new area of the board and the cover, let it "tack up" and then press cover down into position. Keep doing this a little at a time until done. Do a "practice run" first to get your technique down pat.
I used ALL-METAL body filler to make the top of the running board nice and smooth. I did not apply any top coat to the filler. The FL sun has not caused any problems since install in 1988.
http://www.tptools.com/USC-All-Meta...ign=ME-14060&gclid=CJ35l47ao84CFQQzaQodymMFHg
Hope........let me know how you do. Did you buy Drakes covers ?
Question??
Instruction is to start at edge, and also recommended by those that have done it before, But my question is when you glue the edge and let it sit., if i remember right when you contact the two opposite its instant there and will not mouve.
The lip on the rubber looks like to me has to slide on about 1/4"--3/8" am i expecting a problem that is not there????
While I have a ton of respect for your knowledge and willingness to share, I can only agree with you in part on the primer issue.Sounds like some of the old reproductions. A lot of stuff was made in Argentina over the years.
There are as many ways to do a job as there are people who do them. Personally, I would never go without some form of primer. I would put a heavy enough coat of epoxy primer on that a person could sand it well without going through. Clean the sanded surface then apply the contact cement for the boards. The contact cement can act as a primer to a certain degree but it likely has no corrosion inhibitors in it. A good clean sanded surface should allow anything to stick to it whether it's bare metal or primer. You want a primer that will stick as good as possible that the Weldwood won't lift off. The thinners in the contact cement can lift a lot of different primers. The only rattle can stuff I would use would be PTI zinc chromate and it would have to be set in the sun for a week to bake it on good.