Re: To Centerline
red65mustang said:
Question: I applied 1.0 mils of epoxy to the sanded bare steel.
What do you use to sand the epoxy to prep for the filler that won't scratch thru the epoxy?
I think the idea is great but how do you do it and make a mechanical bond of the filler to the epoxy.
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Epoxies in the "automotive aftermarket" are all made to have a 7-day open coat. What that means is the epoxy can have any primer, paint, clear or body filler applied with out sanding the epoxy first for the first seven days. (delayed cure)
After the epoxy sets for 7 days than you need to hand sand the spot that you are applying the filler to with 180 and just a scuffing up is needed.
The benefits:
Ever sand ten year old filler off and noticed the metal had rust?
Epoxy will adhere better to the epoxy than 24 grit grinding marks in bare metal.
The epoxy can increase the flexibility of the glazing putty or body filler by 50% and higher.
Of course when you air-file the body-filler you are going to break through to metal in areas and before going to 2K primer we spray one or two more coats over the whole car again or on panels we did body work.
The test!!! (65 I know you like tests!)
Here is a test for you!!!
Go to Home depot and get an 18 metal Gage panel they are about 18"x5".
On one side grind with 24 grit grinder.
On other side DA with 80 grit. On the 80 grit side spray two coats of epoxy and to be safe let panel set one day (24 hrs as not sure type epoxy your using and cure rate)
Next day with the same body filler mix enough to apply a normal coating on both sides of the panel (Do not sand the epoxy first), Not 1/2 inch thick but normal filling and try to get both sides as close to same in thickness as you can.
SET in corner for one week (no cheating) than bend panel back and forth:
Here is what will happen the filler on bare metal side will crack right away and some if not all, will fall of.
The filler over epoxy side will may not even crack or split. (If your using an automotive grade epoxy)
You will be graded on this.