Thread: Finishing material

Plenty of discussion in the other thread here Kerry, but think of your finish as being comprised of 3 parts.
-pore or grain filler
-sealer
-topcoat

If you want a flat surface as traditional in guitars you will need to use a pore filler on your fijiian mahogany, but it will generally not be needed on north american maples.
The sealer has a number of functions including sealing in colours, preventing penetation of solvents and sometimes improving adhesion.
If I was using a lacquer finish on these woods, I would probably just fill the mahogany and then spray lacquer straight over and dispense with a separate seal coat.
Acryic lacquer spray fom bunnings works well as does the Behlens nitro lacquer spraycans from Guitar Aust.

Nitrocellulose lacquer is a good choice for a number of reasons if you know how to spray and can lay your hands on a good spray gun.
I used excellac 100 from sherwood paints and they also have the specific thinner for that lacquer.


Sherwood Paints - Products - Excelac

It's designed for timber furniture, and is thinner based. It sprays on easily, flash drys fairly quickly, touch drys in about 30min and cures rock hard so it's easy to sand and buff to a high gloss with polish of your choice.

And if you dent, chip or scratch the finish, repairing or touching up with nitro is a fairly simple process.

The data sheet pdf's may be found on the web site.

Hope this helps.

regards to all

Wal

Thanks gents - the Sherwood solution appeals as I don't need a separate sealer. Appreciate the input and suggestions. Cheers Kerry

At last I have got 4 coats of three week aged polyurethane on the LP 59 and it looks good but has some specks and the usual orange peel.
The poly supplier was useless about rubbing and polishing hence this post.

My thinking was a very gentle rub with 1200 wet n dry then 2500.
Then a buff but what to use as the buff agent? I've seen McGuires #2 then McGuires #9 mentioned but it seems McGuires is a US product.

Finally my question ...... (wondered when he'd get around to it )
Is this the right approach and what is an Oz equivalent to McGuires?

Thanks fellas.

Hi Kerry, I have never buffed polyurethane but I have hand rubbed some polyurethane coated furniture that I've built. I used car polish of my choice with some good results. But it needs to be well cured in a dry environment, not easy in this weather lol.

I think the 2500 grit may be a bit over kill but if you've got it, use it, and the polish should do the rest, but I would still recommend that you work your way up through the grits to remove as many scratches as you can that are created by the previous grit.

I used the metal polishing method on mine by changing sanding direction 90 degrees with each grit, this works well as finish has no grain. I think that the more grits you use between the first and last, the better your finish will be. It's a lot of work but it's worth it.

The answers I give are only from my limited experiences.

Other forum members may have better advice.

BTW, where are the progress pics

regards to all

Wal

Originally Posted by Larkan

... and what is an Oz equivalent to McGuires?

Thanks fellas.

Autoglym make some good products that are available here. Check out the auto parts store.

Keeping me honest ay.....good work. Thanks for the suggestions Wal. Did you get a good result which is the main thing? I'm assuming you did.

Some later pics for you to check out. It has been slow but such a rewarding project. The niece it s being made for has just turned 16 and the plan was to have it done for her 16th.......not too far off now. I'd rather get it right than get it done on time. Never make a living as a luthier, way tooo slow.

Cheers

Did you use a single or a 2 pac poly? Most 2 pac polys should be wet and dried and buffed within 24 hours. Nitro's on the other hand left for a week of more. My method for Nitro is a couple of coats of Wattle Rediseal, sanded back, then either satin or gloss Florite Nitro. Florite Paints in Sefton NSW are the best and cheapest small manufacturers I have ever come across. I have been using their products for over 20 years with out any failures. Cheers Paul