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Re: Sanding a Chesapeake hull
By:Paul Jacobson
Date: 12/26/1998, 11:50 pm
In Response To: Sanding a Chesapeake hull (John Stys)

> Hi. I'm building a CLC Chesapeake 17 and having a lot of fun doing it.
> This is my first boat. I have a total of 4 (lightish) coats of epoxy on
> the hull -- and I've got some runs here and there despite being obsessive
> compulsive about such things. My questions are these: how smooth can I
> expect to sand down those runs, and how smooth does the hull have to be
> for a good paint/varnish job? (I haven't yet decided whether to paint or
> varnish the hull.) What should a final sanded epoxied hull look/feel like?

> Thanks to all who respond!!

> John

For a good finish the hull has to be completely smooth: No remaining pattern from the glass fabric. No runs. No drips. No dips or valleys. After the 2nd or third coat of resin you should have gotten the weave filled on your glass, so if you have a visible pattern it may be a case of the resin `telegraphing` the weave. Sand right through that until everything is smooth.

If you should get to the point where you are actually sanding into the glass fibers (you will know it) then you have been way too frugal. Stop sanding and put on another thin layer of resin.

Coarse sandpaper will remove most runs VERY quickly. After you assault the worst things with the roughest paper you have, go to finer grades. Some people have higher standards than me on this and go to incredibly fine grit sandpaper, cabinet scrapers, steelwool, and plastic-abrasive (Scotchbrite(r)) pads. I don't think I've ever used finer than 150 grit before varnishing, and I use that between varnish coats.

All of this sanding should give your boat an awful, matte, whitish, `ground glass' appearance. Not to worry. The varnish will change all of that. Using a bright light held at an angle close to the hull will reveal any high or low areas. Deal with them as you wish, or ignore them. If it turns out that you find a low strip, this is not the time worry about fixing it. A flood light, flashlight, or even a bedroom tablelamp with no lampshade will work fine.

Here is something you might try: When you think you have a nice sanding job, use a damp paper towel to wipe off any surplus dust, then mist the hull with a quick spray from your garden hose. ( I am assuming you are outside ) The water on the hull will give you a better indication of how things will look when the glossy varnish is applied. Old cotton towels, and a few extra minutes in the sun, will work fine to completely dry the hull before putting on the varnish.

Hope this helps.

Paul Jacobson

Messages In This Thread

Sanding a Chesapeake hull
John Stys -- 12/26/1998, 9:52 pm
Thanks! & Cabinet Scrapers...
John Stys -- 12/28/1998, 8:46 am
Re: Thanks! & Cabinet Scrapers...Picture
Joe Greenley -- 12/28/1998, 2:28 pm
Re: Thanks! & Cabinet Scrapers...Picture
Marc Leroux -- 1/11/1999, 6:52 pm
Re: Thanks! & Cabinet Scrapers...Picture
Ralph Wight -- 1/12/1999, 1:57 pm
Re: Thanks! & Cabinet Scrapers...Picture
Marc Leroux -- 1/12/1999, 2:11 pm
Re: Thanks! & Cabinet Scrapers...Picture
Ralph Wight -- 1/12/1999, 9:09 pm
Re: Thanks! & Cabinet Scrapers...Picture
Mike Spence -- 1/12/1999, 1:58 am
Re: Thanks! & Cabinet Scrapers...Picture
Gary Toffelmire -- 1/11/1999, 7:59 pm
Re: Thanks! & Cabinet Scrapers...
Bob Marr -- 12/28/1998, 10:44 am
Re: Sanding a Chesapeake hull
Lee G. -- 12/27/1998, 10:38 pm
Cabinet Scrape drips, sand all very smooth
Pete Ford -- 12/27/1998, 10:19 pm
Re: Sanding a Chesapeake hull
Tony Lima -- 12/27/1998, 7:03 pm
Re: Sanding a Chesapeake hull
Don Beale -- 12/27/1998, 12:02 pm
Re: Sanding a Chesapeake hull
Guy Wright -- 12/28/1998, 10:29 am
Re: Sanding a Chesapeake hull
Nick Schade -- 12/27/1998, 10:33 am
Re: Sanding a Chesapeake hull
Paul Jacobson -- 12/26/1998, 11:50 pm
Re: Sanding a Chesapeake hull
Rick C. -- 12/27/1998, 11:49 am