Which sander for brightwork?

[cnancekievill]

Hi folks,

This question may have been covered before - I have searched the forums but not come up with anything but do just point me to the right thread if there is one.

We have lots of exterior woodwork on our boat, mostly mahogany or sapele. Keeping on top of the varnish is tough and I'm thinking that a better power sander will make the job quicker. This will mostly be for keying and prep as I tend to strip larger areas of varnish with a scrapper and hot air gun. We've got an orbital sander, but this is far too big and heavy. And an old Bosch delta but it is really at the end of its life. Looking at what is available, the choice seems to be between a delta sander, a palm sander and a dual action sander. It isn't clear what the difference is between a delta and a palm (apart from the obvious shape of the base), and how is a DA different from an orbital? Also they all seem to move in tiny circles, rather than back and forth like hand sanding.

What is the best device for sanding long but awkward shapes, tight areas, etc (cockpit coaming is made up of about 5 differently shaped bits of mahogany)?

While we're on the topic of varnish - I've got some black patches of wood where the water has got in under the varnish. I've stripped the varnish off and dried the wood out but the black remains - any idea how to get this off? Varnish also seems to fail badly where it joins to somewhere else (such as the stainless portlights). Do you think this is because the varnish isn't flexible enough to move with the different expansion/contraction rates of the metal and wood, or some other reason? I'm using International Compass, have used Epifanes in the past but the drying time is just too long!

Thanks

 

[Capt. Clueless]

For fiddly stuff, I use my "Multi tool" I got from ALDI. Great little thing with a small triangular sand pad for those awkward little corners etc.

 

[claymore]

Similar to above, I use a Black and Decker Mouse.

 

[richardbrennan]

I have just used my Bosh Multi-Tool with the sanding attachment to do my companion way steps. Working up through the papers, I got a very good finish and also used Compass varnish for the first few coats before moving on to Goldspar Satin for the final coats as it obviously has more grip. However, It would have been a bit tedious to do very large areas.

 

[Little Dorrit]

I have found that sanding by hand is just as quick as using a machine. Sanding machines are good for large flat areas but for small areas hand sanding seems to give a better end result - I tried a multitool but the action cuts across the grain so you will have to finish off by hand anyway... or perhaps I don't know how to use the equipment I have!

Regarding removing black marks it depends how deep they are. If oxalic acid does not work the best solution is to simply scrape out and match the colour using wood filler or simply paint over it with a colour that matches the rest of the wood; if it's a small area it will be fine, for larger areas wait for some other advice...

These are just my experiences and no doubt others will give you some alternative views. I think of varnishing as an art which means over time I have created my own approach to solving the various problems; I doubt if there are two people who go about the process in the same way. I start with 80 grit sometimes then move to 120, 80 grit is not recommended but where the underlying wood is in very bad shape it works for me.

Of course the most important thing to remember is that it's 90% prep and requires a lot of patience and a methodical approach...but I suspect you already know that!

Here's a useful link recently posted on another ybw forum:

http://arthurbeale.co.uk/pdf/Varnishing_and_Painting_Catalogue.pdf

 

[PhillM]

Use a decent sanding block like one of these:

http://www.ebay.co.uk/itm/like/3013...3D710-134428-41853-0%26rvr_id%3D1194068589357

Then get a decent roll of scotch sandpaper.

Beats a machine any day.

 

[Little Dorrit]

+1 for sanding block

 

[Kelpie]

Life's too short to hand sand everything!
Makita do a great wee cordless random orbital, handy not dragging a cord around but it's a 5" so you still need something else for the corners.

 

[Iliade]

Life's too short to hand sand everything!
Makita do a great wee cordless random orbital, handy not dragging a cord around but it's a 5" so you still need something else for the corners.

I'm not convinced that orbital sanders are quicker than hand sanding with a block...

 

[pyrojames]

I use a combo of a whole raft of sanders, blocks and by hand. For large flat areas with heavy build up I will start with a belt, then a 5" random orbital. I use a delta sander for the less fiddly corners and the hand sand/scrape them out. Once the fresh varnish goes on I only hand sand from that point on. I find that electric sanders are just too agressive on fresh (< 7 day old) varnish. The real trick to keeping varnish in good nick, is to do a couple of coats every year, and remove all fittings before varnishing, so you get a continuous coat under the fittings. Not something that I always manage to do....

 

[stav]

When I had my nic 36 the tool of choice for tackling the varnish was a fein multimaster. I never looked for perfect varnish as I wanted to sail her. The most important thing was that it was a sound coating to keep the moisture out. Mine was 240volt and might still get the same as a battery tool would be heavier ans would check out the duration it will run for. Good luck with it.