Do you Finish with Pumice Stone / Rottenstone? (Wood Work)

[o_q]

Do you (or would you) finish wood on your boat with this, or is it just too much work? Also, I would like to know how you guys have a wood working area on-board. Pics are most welcome.

I'm very impressed with the results of this chessboard using this finer abrasive:

Build a Chess Board. Pt.7- Hand-rubbed finish - YouTube

(note: this video is the final part of a series)

[Delancey]

Guy in the video says he is using "lacquer" which could be any number of finishes. Originally "lacquer" was a finish derived from the resinous secretions of the Lac bug from India. Nitrocellulose lacquers replaced them at the dawn of modern chemistry. More recently there are any number of finishes refered to as "lacquers" that are related to neither.

Regardless, lacquers in general are not preferred for marine applications but rather "spar varnishes" tend to be the finish of choice on boats, be they older oil based products or the newer water based products. These varnishes are distinguished from other similar urethane finishes by the inclusion of UV inhibitors which resist the degrading effects of the sun.

Rotten stone is very old school, I can't think if the last time I heard it mentioned, and only in the context of fine furniture finishes. 3M makes a products called "Finesse it" and "Perfect it" which are modern alternatives used with high speed buffing wheels widely used in industry.

I think the best take away from the video is the part about sanding the surface flat, that's the key to a great looking finish. Proper prep and a good gloss varnish will go a long way to getting a candy coating. Buffing is not an absolute requirement.

[o_q]

I guess this means I should use what's preferred for a marine environment, but nothing is stopping me from using those finer abrasives for a nice glassy finish.

[Roy M]

Originally Posted by o_q

I guess this means I should use what's preferred for a marine environment, but nothing is stopping me from using those finer abrasives for a nice glassy finish.

Nothing is stopping you from anything, other than realizing what is the better investment from your pocket for the investment of time from your life, and compared to the options that are more cost efficient and durable.

If shine is the objective, not durability of shine, then go for the quickest, cheapest solution, then repeat regularly. If you have other things to do with your time (and $$$) then consider that shine comes from making a surface plane (flat) to allow light to reflect off of it with parallel rays. The more parallel rays reflecting, the greater the appearance of "shine". Sand flat with a block, then seal and sand off the hairs and dust, then seal with something else and sand flat again, then keep on doing so with ever decreasing grit and thin coats of sealer, varnish, or whatever. Eventually, you have a very flat and very shiny object. If you want to get really crazy, explore "French polishing", which is "sanding" with a wadded cloth dipped in varnish and rubbed until it glows, then repeat, and repeat, and repeat.........

http://www.youtube.com/watch?v=aF7wANfTub8

[Delancey]

By all means, I am a big proponent of experimenting or just plain messing around a bit to see what happens.

Thing is, you can polish a turd all you want, but it you don't flatten out the peaks and fill in the valleys properly you are going to end up with a very glossy but visibly bumpy turd. Pay attention to the video where he shows the reflected light and you can see the low spots that are still glossy because they are too deep in the valleys and get missed by the sandpaper.

If you want to achieve an automotive type gloss you need to achieve a truly flat surface with no peaks or valleys, only level. A rubber sanding block is essential for flat or cylindrical surfaces, no so much with a cap rail or handrail. We used to have stiff leather pads for curved shapes.

Buffing is a great way to take you finish to the next level but there are plenty of wood boat show award winners that haven't seen any buffing. Also, what's the end use? If its interior I say go all the way. If its top sides, well a couple week's worth of grime and airborne pollution is going to knock that gloss off right quick, the question then is what's it worth to you?