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Re: Strip: Best sanding practices
By:Rob Macks/Laughing Loon CC&K
Date: 2/24/2012, 9:13 am
In Response To: Re: Strip: Best sanding practices (Jon Mortimer)

: From the little I understand about this process you seem to be on
: the right track. Stick with the ROS. 40 grit then 120 sounds
: about right. Consider finishing with a finer grit for a third
: round of sanding. The best advice I have seen is here:
: http://www.laughingloon.com/shop.tips.html

: Jon Mortimer

Thank you John.

Yes, please carefully read the section on sanding on my "Tips" page John gave the link.

Very few people understand how to sand. The random orbital sander is the best power tool
for sanding a stripper. The ROS works with speed and grit. Light pressure is more aggressive.

40 grit is too aggressive for softwood on a stripper. If you have strips that don't align
you should fix them before sanding, not use a very aggressive grit to level them, or do
something silly like use a plane. Any strip projecting above the surface more than 1/32"
should be cut on the joint and re-aligned before sanding starts.

60 grit should be your starting grit for soft woods.

If you were sanding hard materials like epoxy / glass, you might need to use each progressive
grit to smooth to a surface for varnish. This would mean using 60, 80, 120, and 220 grits to
remove the cut marks of the previous grit.

How do you know when you're done with each stage? How do you know when all the deep cut marks
are gone? The ONLY way to know is by looking carefully at the surface as you sand.

Lighting is critical! The brighter the lighting the easier it will be to see any cuts or defects. I use
a number of 500 watt work lights to approach what I'd see in bright sunlight.

Starting with the rough hull, scrape off any glue with a scraper. Then start sanding in a small area.
Sand in a circular motion which will make the ROS conform to the curved surfaces. And LOOK very
carefully at the surface. As it changes to a smooth uniform clean surface move on to the next area.

On soft wood you can level with 60 grit. THEN by wetting the wood down thoroughly with a sponge
and water, the cut marks of the 60 grit will be reduced by the grain raised by wetting the surface.
This will totally close any staple holes (squeeze a stream of water over them) and reveal any deep
swirl cut marks.

Then you can jump to 120 grit sandpaper.WET the surface again after sanding with 120 and mark
any remaining deep cuts marks form the 60 grit you missed. Keep sanding and wetting the wood
surface until you can no longer find any cut marks. Then sand with 220 and you are ready to glass.
This wood surface under glass will be beautiful and lustrous.

All the best,
Rob

Messages In This Thread

Strip: Best sanding practices
Robert l -- 2/24/2012, 12:03 am
Re: Strip: Best sanding practices
Jon Mortimer -- 2/24/2012, 6:39 am
Re: Strip: Best sanding practices
Rob Macks/Laughing Loon CC&K -- 2/24/2012, 9:13 am
Re: Strip: Best sanding practices
Etienne Muller -- 2/24/2012, 7:07 am
Re: Strip: Best sanding practices
Eric Mattison -- 2/24/2012, 7:26 pm
Re: Strip: Best sanding practices
Mike Bielski -- 2/25/2012, 2:20 am
Re: Strip: Best sanding practices
Rob Macks/Laughing Loon CC&K -- 2/25/2012, 9:21 am
Re: Strip: Best sanding practices
Mike Bielski -- 2/25/2012, 12:54 pm
Re: Strip: Best sanding practices
Bill Hamm -- 2/26/2012, 1:10 am
Re: Strip: Best sanding practices
Etienne Muller -- 2/26/2012, 6:05 am
Re: Strip: Best sanding practices
Mike Bielski -- 2/26/2012, 8:58 am
Re: Strip: Best sanding practices
ancient kayaker -- 2/26/2012, 12:46 pm
Re: Strip: Best sanding practices
Etienne Muller -- 2/26/2012, 1:10 pm
Re: Strip: Best sanding practices
Bill Hamm -- 2/27/2012, 2:05 am
Re: Strip: Best sanding practices
Mike Bielski -- 2/27/2012, 10:49 am
Re: Strip: Best sanding practices
Bill Hamm -- 2/28/2012, 1:37 am
Re: Strip: Best sanding practices
Mike Bielski -- 2/28/2012, 1:47 pm
Re: Strip: Best sanding practices
Etienne Muller -- 2/28/2012, 1:51 pm
Re: Strip: Best sanding practices
Justin -- 2/29/2012, 5:29 am
Re: Strip: Best sanding practices
Kirk Fredericks -- 2/29/2012, 5:22 pm
Re: Strip: Best sanding practices
ancient kayaker -- 2/27/2012, 11:16 pm
Re: Strip: Best sanding practices
dave g -- 2/28/2012, 12:42 am
Re: Strip: Best sanding practices
ancient kayaker -- 2/28/2012, 10:37 am
Re: Strip: Best sanding practices
Bill Hamm -- 2/28/2012, 1:40 am
Re: Strip: Best sanding practices
george jung -- 2/28/2012, 12:01 pm
Re: Strip: Best sanding practices
Bill Hamm -- 2/29/2012, 1:48 am
Re: Strip: Best sanding practices
John Abercrombie -- 2/28/2012, 3:48 am
Re: Strip: Best sanding practices
Rob Macks/Laughing Loon CC&K -- 2/27/2012, 11:08 am
Re: Strip: Best sanding practices
John Abercrombie -- 2/27/2012, 1:03 pm
Re: Strip: Best sanding practices
Rob Macks/Laughing Loon CC&K -- 2/28/2012, 4:15 pm
Re: Strip: Best sanding practices
dave g -- 2/27/2012, 10:41 pm
Re: Strip: Best sanding practices
Dan Caouette (CSFW) -- 2/27/2012, 11:55 am
Re: Strip: Best sanding practices
Mike Bielski -- 2/27/2012, 7:56 pm
Re: Strip: Best sanding practices
dave g -- 2/27/2012, 10:09 pm
Re: Strip: Best sanding practices
Bill Hamm -- 2/27/2012, 2:02 am
Re: Strip: Best sanding practices
Scott Fitzgerrell -- 2/27/2012, 11:56 am
Re: Strip: Best sanding practices
Ian Johnson -- 2/26/2012, 6:37 pm