# Pre-glass sanding
**URL:** https://forum.clcboats.com/t/pre-glass-sanding/42578
**Category:** Builder's Forum
**Created:** [September 28, 2014, 12:56am UTC](https://forum.clcboats.com/t/pre-glass-sanding/42578 "2014-09-28T00:56:13Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@Gero\_Verheyen](https://forum.clcboats.com/u/Gero_Verheyen)
#### Post date: [September 28, 2014, 12:56am UTC](https://forum.clcboats.com/t/pre-glass-sanding/42578/1 "2014-09-28T00:56:13Z")
I just thought I'd ask before I get down to glassing my Shearwater build - in the manual it talks about sanding down the hull with 120 prior to putting down the glass. I was thinking of going down to 220 before laying down the glass to get the smoother finish - will it really make a difference?
I know some builders go down to 400 wet sanding on during the final glass / varnish sanding, and I intend to go to at least 400 at that stage.
Thanks,
Gero
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### Author:  [@Howard\_Spira](https://forum.clcboats.com/u/Howard_Spira)
#### Post date: [September 28, 2014, 3:53pm UTC](https://forum.clcboats.com/t/pre-glass-sanding/42578/2 "2014-09-28T15:53:36Z")
there is no real relationship between the final finish sanding (once it is glassed/fill-coated varnished) and the sanding you are talking about pre-glass.
pre-glass you want to sand only as much as you need so there are no scratches or glue smudges and so the glass does not snag on the surface. you can't hurt it by sanding it to 220 but not really necessary either.
most important, is don't sand through the veneer which is relatively thin....unless you intend to paint.
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### Author:  [@Jeremy\_Clark](https://forum.clcboats.com/u/Jeremy_Clark)
#### Post date: [September 29, 2014, 8:55pm UTC](https://forum.clcboats.com/t/pre-glass-sanding/42578/3 "2014-09-29T20:55:24Z")
2nd vote: 120 grit to round the corners and get the splinters off so the glass doesn't snag. for after the glass, I usually go glass, one fill coat, 80, 2nd fill coat, 120 third fill coat and 220 before varnish. 320 between varnish coats. I build boats that get abused, so I am not looking for a furniture grade finish. Also consider graphite for the bottom.
Good luck, JRC