Finishing by hand...what to use?

kiwigeo · Post by **kiwigeo** » Wed Oct 29, 2008 5:08 pm

Bugger the double......just ask 'em to hand over the bottle. Drinking from a glass is for pansies.....drink straight from the bottle and it saves on a whole lot of washing up.

gratay · Post by **gratay** » Thu Oct 30, 2008 3:02 pm

Questions , questions..
my apologies guys.....but hopefully this helps more people than just me .

For those that use Z-poxy..Do you wet sand it or Dry?

and as I want to do a gloss finish...would I need to go to a finer grit with leveling the Z-poxy so that the top coat of tru-oil gets a good transparent gloss when I buff it.?

thanks for any help,
Grant

kiwigeo · Post by **kiwigeo** » Thu Oct 30, 2008 3:39 pm

I dry sand zpoxy prior to french polishing. I take it down to bare wood but others just lightly level off the zpoxy.

Allen · Post by **Allen** » Thu Oct 30, 2008 6:17 pm

I've tried both wet sanding and dry. By far the best results was dry. A much more consistent finish. I tend to take it down to the wood, and then re-coat the instrument with epoxy cut 50 / 50 with metho. I apply this with a lint free cloth and just wet the surface out nice and even. Something like sealing it with a coat of shellac.

The one time I didn't do this, I noticed some slight discoloration between wood that had been sanded through and areas that hadn't been. I suspect due to the different "wetting" properties of the epoxy and the lacquer that I use. I'm pretty sure that you'll experience the same with using tru-oil.

gratay · Post by **gratay** » Thu Oct 30, 2008 8:13 pm

Thanks Martin and Allen,...thats very helpful
I've seen some pics of the discolouration so I'll definitely be putting on a washcoat.
cheers.

gratay · Post by **gratay** » Thu Oct 30, 2008 9:32 pm

Well,
I put the first coat of Z-poxy on ...left it 24 hours and went to sand it tonight..
I know nothing about finishing I realise as soon as I started sanding.
What I want to acheive is to level the Z-poxy and leave a film of it on..mainly because I'm using an oil finish.

I started out with 400grit which seems ok but I feel its a bit fine ..
Should I keep sanding until all the shiny spots disappear..because when I do that it feels like I'm virtually back to wood?

cheers Grant

kiwigeo · Post by **kiwigeo** » Thu Oct 30, 2008 9:49 pm

Grant youll need a minimum of two coats of full strength Zpoxy. On my last guitar I did three neat coats and then a 50/50 wash coat wiped on with a cloth.

As already stated I sand all coats back to bare wood. You need to first decide if youre going to do this or your end aim is a smooth coat of zpoxy covering over the wood. Youre going for the latter so keep coating and then lightly sanding until youve got a level coating of zpoxy over everything with no bare wood showing through. I sand with 220 or 400 grit paper.

Allen · Post by **Allen** » Fri Oct 31, 2008 6:35 am

If you're going for a glass smooth surface, then with almost every wood that I've used epoxy on, then it's a bare minimum 2 full strength coats. Most have been 3. I sand with P220 or P240, whatever is on hand, just to get the finish level. There is no need to go finer until you are preparing for the final finish. If you still have shiny spots after leveling, then it's telling you that they are still low. Once you feel that you are ready for the final wash coat, then go to your finer grits.

I'd recommend that you sand back to bare wood, or very nearly so, just leaving the epoxy in the pores until you are ready for the wash coat on this first instrument. You can't stuff it up doing this, and there's no possibility of getting the epoxy too thick this way.

gratay · Post by **gratay** » Fri Oct 31, 2008 9:43 am

thanks guys yet again.
I think that is sound advice to sand back to bare wood.
One thing I found was it goes on quite easy especially on a reasonably flat surface like a back but I got it a bit thick on areas where I had to use the gloved finger..
The second coat I'll try getting a lot more of it off the surface .

While the credit card works well for the back I found it a bit harder on the sides to apply with the card...
Do you guys use any alternative methods to apply to the sides?

Cheers Grant

kiwigeo · Post by **kiwigeo** » Fri Oct 31, 2008 10:18 am

I use the credit card on back and sides. If youre going with the grain and the sides arent perfectly flat then you can get uneveness.

Allen · Post by **Allen** » Fri Oct 31, 2008 6:14 pm

Wack it on, spread it around with the applicator, and scrape it off. No real secret to it. If you get little sags, puddles, bug shit etc. try using a razor blade or similar as a scraper to level it before you start to sand.

gratay · Post by **gratay** » Fri Oct 31, 2008 6:45 pm

thanks guys. I think I've got the picture now..

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Finishing by hand...what to use?

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