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markbrai
2nd August 2006, 07:38 AM
First off, I know this isnt really woodwork as such, but then again its made of wood and im working on it so maybe it is!!

Im building a guitar over the summer and am ready to start finishing it.

I have a Swamp Ash body which I wish to finish in an opaque coat of colour.

The paint I am going to use is (most likely) Plasti-Kote Super Gloss.

I went to our local decorating supplier today and asked which sealer I would need for Ash if I was going to be using Plasti-Kote on it. The guy said to me that it wouldnt be needed which confused me a bit as I'm pretty sure it does!

I was just wondering whether it does need to have some sort of sealer applied or whether a good fine sand all over and then a couple of layers of primer (Plasti-Kote again and finely sanded in between) would suffice?

I'm in the UK if that means anything (just in case there are any suggestions of products from anyone in the states which I might not be able to get hold of here!)

Cheers in advance!!

Plasti-Kote Super Gloss page (http://www.plasti-kote.co.uk/site/productsdetail.asp?PRODUCT_ID=18#)(if any info is needed)

rockinrob
2nd August 2006, 07:39 PM
Hi Mark, finishing can get really confusing- as companies use different terms for different products, and many products don't actually tell you what they are (or what's in them).

Technically, your first coat of anything is a sealer. The advantage with a "sanding sealer" is that it's softer, so it's easier to sand. The goal is to create a level surface to start your color/top coats. A lot of people don't like it because it is softer, and in general it's a bad idea to cover a softer finish with a harder one. But most of the major companies use it because it saves time.

A couple things about ash- it's an open pored wood. Often people will fill the pores on woods like this (along with mahogany, oak, walnut, etc) in order to get a level surface. There's absolutely nothing wrong with NOT filling the pores, it's a matter of choice. I've not filled them on mahogany and walnut for cabinets. It looks good on guitars with a natural finish, where you really want to see and feel that it's wood, but if you want a smooth, mirror finish (like you might with an opaque color coat) you'll want to fill them.

You can fill the pores with either an oil based or water based filler, depending on the following coat. You can also use an epoxy, but I've yet to try that. Another option is to use the sealer or a clear coat to fill the pores. The process is you spray a coat of finish, let it dry, then sand back- just leaving the finish in the pores. You repeat untill the pores are totally filled. IMO, this is a pain because it takes awhile, and it's hard to tell if you've filled them adequately. Also if you use laquer it will shrink with time, so your finish may look great for a couple of months, and then you'll start to get dimples over the pores.

So, let's say you decide to fill the pores, do you still need the sanding sealer? Personally, I think it's a good thing, because it IS easy to level, but it will also seal in the pore filler. Plus it's cheap, and you can brush it on (if you don't have spray equipment). But it isn't necessary, and depends on your color/top coat, because everything needs to be compatable.

OK- where am I? Right- paint. Is that spray paint an enamel paint? The traditional paint for guitars has been lacquer. With Fender guitars it was nitro and acrylic lacquer, and it was the same stuff that was used on cars at the time. I have no experience using enamel based stuff, but if you want to protect the color, as well as rub out to a nice gloss you'll want to clear coat the color. On that site in the blurb it says they offer a clear coat for that product, and it may work great, but I couldn't find out what it is. You may have an issue with trying to get a nice, smooth finish. When you try and rub it out it may get gummy or sticky which is a pain, especially on the back of a neck. The main issue is that everythings compatable- you don't want to run into problems of your clear not adhearing to your color. And you want a clear coat that is durable, but easy to rub out.

If you decide not to use those products, there are many companies that offer nitro lacquer in rattle cans, Deft and Mohawk are two. You can also get spray poly, and wiping on poly is an option. There are also brushing lacquers out there, but I've not tried them and I've heard mixed results. IMO, lacquer should be sprayed. You could try brushing a waterbased lacquer, that might work better.

Sorry about the rambling, but there's a lot to it. There's a company called The Guitar ReRanch that offers a lot of great finishing products, but they're only available in the States. But the site has a lot of great info on it as well as a forum, so you should look it up. And I often see posts of guys looking for finishing stuff in the UK on various forums, so if you do some searches you may find some good products you can use.

Good luck!

rockinrob
2nd August 2006, 07:49 PM
Here the link for the ReRanch site;

http://home.flash.net/~guitars/ (http://home.flash.net/%7Eguitars/)

markbrai
2nd August 2006, 08:45 PM
Rockinrob, that was quite possibly the most complete and helpful response I have ever got from any forum ever!! I actually understood every word you said!!!

I think I'm probably going to go down the route (as you suggested) of filler, sealer, paint although still not 100% on the sealer. Looking a bit more into the Plasti-Kote site, they seem to say that the Primer is a good idea to use to seal the wood, so im thinking that I'll fill the grain and then bung a couple of coats of primer on top and sand between them and use that as the sealer. Then put the colour coats on top and the clear on top of that.

I agree with your concerns about the clear coat and whether it will rub up, I asked plasti-kote about this about a week ago and their repsonse was "don't know"....which was helpful!!

I think I'm gonna just have to try it on something beforehand and go from there!!

Cheers for the help!!!:D

rockinrob
7th August 2006, 05:50 PM
Good- glad I could help! :D

Just remember, everything needs to work together. Your primer might not bond well with the wood filler. In general it's a good idea to seal in the filler before moving on to the next step.

The other day I saw someone post about these products on a guitar forum and I thought of this thread. They look similar to the ReRanch products, and are from the UK. Might be worth a look;

http://www.manchesterguitartech.co.uk/lacquer.html#custom