68 non A/C core support finish

[Chuck R.]

I finally got the POR-15 and nitro stan putty off of my core support and have noticed what appears to be what's left of possible paint drips/runs.

Were the supports dipped?

It's one of those easy to duplicate things I'll take a few minutes to replicate if it was indeed dipped and if I have an idea which way they were hung to drip dry.

I'm afraid that the blast cabinet errased any evidence.

Thanks,

Chuck

[Terry F.]

Re: 68 non A/C core support finish

Chuck, I believe they were dipped and installed. Later, when the engine compartment was getting blacked out, they got hit again. Not certain of that though. I do wonder if the upper air dam was installed when this happened also. I sort of think it wasn't. Thanks, Terry

[Chuck S.]

Re: 68 non A/C core support finish

Chuck, I'm not sure what part you're talking about; on 70s the AC condenser bolts to the radiator support.

But regardless, if the part is a satin black, it is a virtual certainty that it WAS dipped. If you have the "remains" of the runs, you can probably figure out which mounting hole it was suspended from with a little study. When you beadblast a part, the thickest part of the run gives it up only with protracted concentrated exposure to the blast. This will include the lower sides of the run, as well as, the leading edge.

For example, if you have the faint outline of a small "arc" remaining, then that is probably the leading edge of a narrow run...look for a logical suspension point directly away from the open or concave backside of the arc. The entire end of some runs may be dried into a thick "dot" that is almost impossible to remove...the thickest part of that "dot" is your leading edge. "Sags" are a little more difficult to figure...at the risk of confirming my membership in "Kooks of America", if the sag has an "angle", the angle is pointing to the low point of the sag. Ah heck, you're smart; you'll figure it out.

If you can't figure out how the part was suspended, I wouldn't worry about it...just hang it on a mounting hole and do your paint thing. Who's going to grade your runs at this point...you'll probably be the sole remaining individual on the planet that knows how they dipped this part, or cares. Now, runs on frames, that's another matter; better have'em right cuz someone smart figured it out and wrote it down.

[Chuck S.]

Re: 68 non A/C core support finish

Runs, OR THICKENED PAINT ON EDGES, on dipped parts occured primarily on the "bottom" portion of the part. Primarily you will find unobtursive runs at the lower portion of the parts where it pooled, or where it had had time to flow down from the top of the part and began to set up with time passage.

The paint used was a THIN primer that virtually "sheeted" off the part as soon as it was taken out of the dipping barrel. That was why they used it...it provided a nice smooth virtually run-free finish, thorough coverage inside and out, without waste from overspray or time/labor lost to the spraying process.

[Chuck R.]

Re: 68 non A/C core support finish

Thanks to you both for the responses.

It's one of those not fun to remove parts that while it's out hanging on the wire I could play with and not take a ton of time to do.

I DO have an idea on where the runs would have collected, but wasn't sure as to the gravity direction.

It's not worth me spending a ton of time on unless you tell me that it's worth another 10K to those hard core buyers when wifey sells off my toys when I kick off

Chuck

[Chuck S.]

Re: 68 non A/C core support finish

If you know how the part was hung, and you can dip the part anyway...Why not?

It's originality preserved, and that's a good thing. On the othere hand, if it's a large part that is not practical for an individual restorer to dip, it's probably not worthwhile IMO...conventional spray painting without tricks is the way to go. NCRS does not judge for the presence of runs...only that if there ARE RUNS, then they had better be in the right direction (and this will be on the frame AFAIK).

I have tried replicating dip painting runs by overspraying very wet coats where I wanted a run. What I found was the effect was not equivalent. The dynamics of spraying versus dipping are just not the same; when you spray, the process is DESIGNED for the paint to stay where you put it. When a part was dipped, the paint was intended to sheet down the part, gathering momentum on the way...the excess ran off the bottom, and ideally, left only a little thickening at the lower edge due to surface tension.

In my opinion, dip painting runs occurred only when the process was slower (higher paint viscosity, lower temperatures), or the ambient temperature was higher allowing the paint to begin setting up before the run-off was complete. Looking back on my attempts, the error was in not over reducing the black paint more to simulate the thin primer used.

[Chuck R.]

Re: 68 non A/C core support finish

Yeah Chuck, I figure that the paint must have been "thickened" by excessive pigment or almost not thinned at all and then baked.

I was going to thicken primer and dribble it in strategic locations and then hit it with a heat gun to stop it in it's tracks. Then top coat it.

I might just try it for grins and giggles anyway.

Is there more "Chucks" on the board these days or is it just me?

Chuck 32205