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Doug Arndt
07-07-2009, 12:58 PM
Doing a stitch & glue kayak, with varnish deck.
I've sprayed (hvlp) several coats of varnish, but I'm getting an orange peel finish.
What do do next ? Continue on, light sanding, major sanding ?
Then ... abandon the spraying and use the foam brush, or are there some spraying tips.

Mac McQuinn
07-07-2009, 1:16 PM
Doing a stitch & glue kayak, with varnish deck.
I've sprayed (hvlp) several coats of varnish, but I'm getting an orange peel finish.
What do do next ? Continue on, light sanding, major sanding ?
Then ... abandon the spraying and use the foam brush, or are there some spraying tips.


Doug,
I have no experience with HVLP applied finishes but have some in Varnishes. Was this a Spar type Varnish? If so you might be pressed to get it to harden up enough to sand and buff. If it's not a Spar item, you should be able to flatten the finish with pad and w&d sandpaper working up to as fine as 1200 grit which is available at automotive refinish centers. At this point you could buff it w/ compound or start applying varnish again. I've had great luck with brushing varnish w/ a quality brush that's cut 1/3 with appropriate thinner. Good luck and take your time.

Mac

Doug Arndt
07-07-2009, 1:35 PM
Thanks Mac, yes, it's marine Spar varnish by Interlux Schooner.
Instructions call for 3-5 coats, by foam brush, and I figure a spray coat is thinner, therefore will need more coats. So far I have maybe 3 spray coats, but you can see an orange peel finish when viewed from an angle.
I don't want to continue if this needs fixing at this point, it's been several weeks and it's hard enough to sand. So I'm wondering if I should do a serious sand off, or a light sanding to flatten it before adding additional coats.

Mac McQuinn
07-07-2009, 4:46 PM
Thanks Mac, yes, it's marine Spar varnish by Interlux Schooner.
Instructions call for 3-5 coats, by foam brush, and I figure a spray coat is thinner, therefore will need more coats. So far I have maybe 3 spray coats, but you can see an orange peel finish when viewed from an angle.
I don't want to continue if this needs fixing at this point, it's been several weeks and it's hard enough to sand. So I'm wondering if I should do a serious sand off, or a light sanding to flatten it before adding additional coats.

Doug,
Did you determine what is actually causing the orange peel with your gun? IE. too much pressure, varnish/thinner ratio, or too much varnish, etc. If you have and have done a few practice passes and are happy with texture results, I'd flatten what is there and re-apply the varnish. Perhaps people at Interlux can give some insight on application technique w/ HVLP type gun.

Mac

Neal Schlee
07-08-2009, 11:52 AM
Are you letting each coat dry before applying the next? Trying to build too many coats too fast can cause orange peel.

Neal

Doug Arndt
07-08-2009, 12:31 PM
No, haven't determined the cause, hoping to get some hints, seems to be a lot a variables. The varnish was thinned, otherwise it either didn't come out of the gun or was dry. (Too much "wet" and it runs as well)
The last attempt was two coats maybe 4 hrs appart, the surface was dry to the touch, but i'm sure it was still soft underneath. I wouldn't try sanding it at that point. Neal's comment suggests that may be an issue.

Jerry Casler
07-10-2009, 10:31 AM
take it from an old paint and body man , orange is usually caused by incorrect setting on gun. I listed a website here for you to go to for your problems and how to correct them. Hope it helps you and good luck.:)

http://www.finishwiz.com/orangepeel.htm