SKim coat questions

jsouthco68camaro · May 27, 2006

I am ready to put on the skim coat after getting the quarters as straight as possible. I have a few questions on this process though.

1. When working with a large area, how do I determine how much is not enough of the hardener for the filler? ( I run into problems with the filler setting up before I have spread it all and was told to use less hardener for this)

2. Should the filler be applied with up /down strokes or running the length of the panel horizontally? Or does it make any difference at all?

3.When done-Is this blocked out at a 45 deg angle or just up and down paralell to the body lines?

4.With the flares on the fenderwells- should these be done first and then feather the panel to match or vice versa?

Hope not everyone is gone for the weekend, I could sure use some tips!

69RS-Yenko · May 27, 2006

If your going to skim coat the whole Qtr. I would look into a spray poly. that way you can get it to cover nice and even, block that down and putty coat your lows.

MARTINSR · May 27, 2006

Wow, you have asked a ton and I am going out the door right this minute for along weekend.

1. Don't try to spread it out all over the quarter in one application. I do this stuff for a living and wouldn't try that. Spread your polyester putty (if you deside to use it, the polyester primer suggested in the last post is a very good idea) with pressure, very thin, THEN get some more on the spreader and spread over that with a little less pressure to provide some filling. Press it down very thin as you feather it off at the edges. Now, apply only an area large enough that you can handle. Just spread it out, then clean up your board and mix up another batch and start where you left off, spreading out thin on those edges where they over lap as to not build up a bunch. I do this all the time, it really works well.

2. Horizontal except over the wheel well.

3. There is no right answer to this one. You block in every direction.

4. I sand the flat areas out first, then do the detail.

Brian

Steptoe · May 27, 2006

Do u still have steel or got to puuting the expoxy on stage?
Using a long sanding block with 280 paper, lightly block the expoxy, diagonal in both directions.
This will show your low spots.
Depending on just how low, determins as to using a skim of bog, or spray putty. Sry I cant describe how low is which..it is a sort of seat of the pants/experiance thing, wouldnt know how to measure without specialist tools.
Going from your post, if the work so far is ok, spray putty is the option.

If i skim the Whole panel, u then loose the reference pionts for shaping curves and lines...hence why not recomended above.

jsouthco68camaro · May 27, 2006

Thanks for all the replies... As always this site is a huge help....

I applied a very light coat of filler over the entire panel and blocked until smooth. I then sprayed a thin guide coat over the top and blocked again to check for any variations. I only have a few small spots that are low and have a few where the metal has started to come through.

At this point do I add a little more filler to the low spots and reblock these areas?
I am assuming I want to be able to block until all of the guide coat is gone, with any metal just starting to show when I finish.....

MARTINSR · May 29, 2006

It is very hard to say what you should do without seeing and feeling it. You have to look at "concepts" of the work and then decide on your best plan of attack. If you only have a few spots, sure, a little polyester putty applied with pressure as to not have a thick edge should do the trick.

The hard part is feathering out these patchs among the larger filler. It is VERY easy to cut into the underlying filler when you sand the polyester putty. So use NICE NEW, SHARP paper and throw away the paper the second it gets a little clogged. Block ONLY on the polyester putty being VERY careful not to cut into that underlying filler.

Brian

69 350 SS · May 29, 2006

69RS-Yenko said:
If your going to skim coat the whole Qtr. I would look into a spray poly. that way you can get it to cover nice and even, block that down and putty coat your lows.

ditto that

MARTINSR · May 29, 2006

A quick note on that polyester primer idea. The best thing about polyester primer is that when you do block it, you aren't "focusing" on any particular spot. Just by human nature you simply block the whole thing much more evenly....because it is more evenly applied.

If you block the skim coat of polyester putty the same way, blocking to acheave a uniform film thickness BEFORE trying to block it flat you are on your way to "getting" the whole skim coat idea.

Brian

jsouthco68camaro · May 29, 2006

I ended up using regular filler and just sanding alot back off. The panel seems flat ( I had used a guide coat and all seems to be coming off evenly.)
I have no experience whatsoever with Poly putties....

SHould I continue to block until metal is just starting to show through?

I dont know how to determine if the thickness of the skim is right unless I take off nearly all of it, waiting for the metal to start peeking through.

Is this correct?

Jim

MARTINSR · May 29, 2006

If the metal is reasonably straight you can block until you see some metal coming thru, then STOP. You want any edges of the filler to be "transparent". If you see "polished" metal or filler with sharp, defined edges that is a dead give away that you sanded too much.

And of course you can only hit metal at all if those metal spots are at the right level. If you have a low area where there are metal spots higher than the bottom but not as high as the surface of the panel should be, you certainly don't want to keep sanding until you hit them!

If you bring the filler (be it skim coat or not) down evenly while always maintaining the basic shape of the panel and STOP when you start seeing the metal that you know is proper, you are there my friend.

Brian

SKim coat questions

jsouthco68camaro

69RS-Yenko

MARTINSR

Steptoe

jsouthco68camaro

MARTINSR

69 350 SS

MARTINSR

jsouthco68camaro

MARTINSR

Top Contributors this Month

Recommended Communities