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Will POR-15 sandblast off?

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Norton47

Jedi Warrior
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Will POR-15 sandblast off once applied?
I have a front wing ( fender) that has pitting on the lower rocker. I was wanting to use this process https://www.diversifiedcustomcar.com/metal_spray.shtml
to repair it, but time and money may not let me. Anyone used this process?

I was thinking about painting it with POR-15 on the inside only as a temporary measure and then doing a final repair later.
I know I should do it all now but that's not real.
The rocker also needs so repair and I want to get the engine in and be able to drive it to my welder and patch that also. So that is later this summer when it's most likely dry here.
I just want to stop or slow down the rust until then.
Here are some photos
https://s225.photobucket.com/albums/dd50/...nt=P1010018.jpg
 
POR-15 will sandblast off but with great effort. It would be very difficult to impossible to remove from thin metals without warping.
You might try something like Extend, that would eliminate the rust but leave behind a paintable surface which would require far less prep work. Or just preserve it with spray paint.
 
I am assuming you are not planning to drive the car other then to the shop to repair that rocker. If so, and if the car is not in the weather, don't worry about the rocker, it's toast.

I am not familiar with the metal spray process you referenced, but the link implies it is a process they employ and not a DIY job. Your wing looks pretty holed. Sand blasting or chemical dipping will hole it even more. Anyway, you might want to send the company a picture of what you have and see what they say. You never know, perhaps this company can salvage it.

As far as preserving what you have left until you decide what to do, I would just spray it with appliance lacquer available at ACE. When the time comes it comes off easily with paint stripper or media blasting.
 
Well, I have done what you suggested. I sent photo's and an email so we will see what they say.
Yes with the fenders off, the driving was to be only to the weld shop.
On the rocker I used a large borescope that I have and the rust is only in the rocker forward of the A post. So I think I will buy new outer rockers and splice in the forward part. We will see more of course when it's cut out, the inboard sill wall is sound. The end cap will also need replacing.
So it looks like work is going to send me to Singapore in a day or two, which means some overtime. We talked it over and we are going to fix it up right now. I have had the rear fenders off and now the fronts, so I think this is will keep me fairly sound until I can do a frame off tear down.

Is there a standard improvement for that blasted cowl drain?
Or just plumb down through the top of the rocker and turn it 90 degrees and go out the inboard sill wall and dump under the car.
I was thinking about using PVC and grommets where it would penetrate on of the metal surfaces.
 
Dummy I am, I'd probably place a thin sheet of
fiberglass painted into place with POR-15 silver,
trying to place to the back side first, if possible,
or right over the top, if you have to (thinnest
fiberglass will be smooth surface). Get all rusted
surfaces painted. Then a light coat of POR primer
spray; bondo filler to smooth out holes;
sand; primer and paint.

That's what I'd do; but, then, I'm not a frame-off
guy, obviously, and just too ignorant to know better.

The trim on my '69 truck bed kept coming off.
I drilled 1" holes to install better fasteners.
In order to quickly cover/hide these holes, I used
this fiberglass/POR process thinking I would have
to also fill with bondo. No bondo required. After
paint, I have to actually look hard to find the holes.
I wanted to be able to see them in the event I had to
enter again. The paint finish is one of these
splatter-type paints, but I think with bondo and
smoothing, you'd never know there was a problem.

POR and fiberglass is some tough combo. Can't testify
to tensile strength, of course, cause I just don't
know.

Get you to frame-off, I'm sure.

Oh, and POR vendors sell strippers appropriate for
their paints. Works.
 
2wrench
hmmmm, don't make me think down those alleys!!! LOL
But I am reconsidering how to fix the rockers! I might use something like that for now then just cut it all out when I weld in new. Need to do some more exploring on the rocker to see the extent of the rust.
I am going to call the metal spray guy today, hopefully he will be in and not on holiday.
 
The cowl drain is just one place water enters the void between the inner and outer fender. Water also comes in from the trough under the rear of the hood so fixing the cowl drain only addresses pat of the problem.

I just put a lot of work into sealing the inner area with epoxy primer and left it at that.

But if you want to do this, you can also route the drain out the front and down, thus avoiding through the rocker.

Fender repair.

This will upset the purists out there, but if the lower fender has enough metal to provide strength, after removing the rust, you could use a fiberglass strand filler applied to both sides just enough to fill and span the holed areas. Sand to contour and apply a skim coat to smooth it out.

One caution, at least on my fenders, this area does flex when bolted to the rocker, so any repair must be able to accommodate the minor distortion when fitted.
 
Ray
Thanks for the tips. When you say epoxy primer is that over POR-15? Would POR-15 be enough in your opinion.
I spoke with the fella at Diversified and they can do the fenders and I am taking them to him tomorrow morning. He says done this week. I will make sure to ask about flexing.
 
I am looking forward to see how that fender comes out, it could be a lifesaver for many of us as the best parts are the ones that came with the car.

I have not used POR-15 or Eastwood's products for various reasons, the two most important to me are the inability to easily spray them on and top coating issues. These two products are designed to go over non-flaking rusted metal. To apply over new or rust free metal you need to do the same preparation as for an epoxy.

If you have rust free metal, then (IMO) the use of a two part epoxy primer is as good as if not better then the other two products. But it must be sprayed on. The epoxy primer is non-porous and tough and does not need a topcoat if so desired. Most epoxy primers have a window in which to topcoat without additional prep. After that window closes, you need to scuff the surface, apply another coat of primer then topcoat.

All this said, I do use SEM RustShied with their hardener, which is designed to apply over the same type surfaces as POR-15. The difference is I can brush or easily spray it on depending on the situation, clean the gun with lacquer thinner, and not worry about what I did not use setting up in the can. While I have not applied a urethane topcoat over it, I have tested the epoxy primer and after a rigorous scuffing, the primer adheres just fine without lifting. Lastly, for those sloppy people like me, it can be removed from your skin without a chisel.

I just finished doing a rear wing that was rust free. On the inside I brushed SEM RustShield into the areas I could not spray, then sprayed the rest of it. I did this three times as directed. The outside of the fender needed some minor applications of filler, then I shot the epoxy primer and a moderate build primer. Came out great.

All this said, POR would probably do just as well inside the fender, but for the outside, I would not use it.

I am sure there are differing methods and opinions that others have found also works well.
 
TR6Oldtimer
I dropped off the fenders this morning. He will repair with a silicon bronze metal spray. Never have to worry about rust on that material again. He is able to spray several different metals. This is a take off from flame spray treatments used for years on crankshafts and other applications. He had lots of photos of older cars and Camero's and Mustangs that had lots of rot and this did the trick.
As the fender was off, he plans to spray the inside for the strength and build and a light coat on the outside to smooth and blend. We will see. I will get them when I return home. The price is decent also.
Now I have to go to Singapore for 8 to 10 days and then back home and deal with the rockers. The inner sills look ok, the right rocker has that hole, but I think I am going to cover the car and sandblast the whole rocker and then see. The left side is worse, the very front of the sill has the lower corner weakened and the outer rocker is rotten back to the door. The splashguard has the lower outer corner rusted out. The tub sidewall and the firewall all look sound, no rust, shiny paint or primer. Down the rocker looks ok but will need closer examination. Lets hope for the best and look hard. Thinking about cutting the rockers back to sound metal and welding in that section from a new rocker. I can't find any issues around the A or B posts.
 
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