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mikeyb2
11-22-2017, 11:22 PM
Hi everyone, so far I've used Truoil on the few instruments I've made. I like it and my results are getting better. However, I want to make an instrument( a guitar) with a spruce top and I'm thinking a more protective finish will be better, such as laquer.
I won't be buying spraying equipment for 1 or 2 instruments a year, so it will be aerosols.
Can anyone describe the process step by step to achieve a decent gloss finish with the above, or post a link to a video showing this. Also, if certain products are recommended please bear in mind I'm in the UK.
Thanks Mike

Jason Wolverton
11-23-2017, 08:27 AM
I like the Behlen/Mohawk stuff the best. I recommend keeping the coats thin and building it up very slowly, lightly sanding out imperfections between coats. Aerosol just doesn't atomize as well as a spray gun, so you're going to have to deal with some annoyances. I'd also get a can of No Blush Retarder that you can use to help flow out runs, uneven spots, or blushing. Use this stuff sparingly- it will eat through your finish in no time flat. I just lay down a mist when I need it.
http://www.mohawk-finishing.com/catalog_browse.asp?ictNbr=254

Also, I'd lay down a good bit of shellac as a sealer under your lacquer. That will make everything work a little better.

Andyk
11-23-2017, 11:28 AM
Warming the can a little also helps

DPO
11-23-2017, 11:33 AM
Or you could avoid all the pitfalls and environmental/health issues and go the organic route and use shellac. Easy to apply, quick drying, and provides a good finish which is forgiving and very easy to touch up.

photoshooter
11-23-2017, 02:20 PM
Shellac is my favorite finish but if you want to go with lacquer there is also “brushing lacquer” available here in the states. It can be brushed or wiped on.

Brushing laquer (https://www.homedepot.com/p/Minwax-1-qt-Clear-Semi-Gloss-Brushing-Lacquer-15505/100558814)

There is also the Preval Spray System (https://www.homedepot.com/p/Preval-Spray-System-0226/203826746) for spraying thinned finishes.

sequoia
11-23-2017, 07:40 PM
Or you could avoid all the pitfalls and environmental/health issues and go the organic route and use shellac. Easy to apply, quick drying, and provides a good finish which is forgiving and very easy to touch up.

I too would encourage you to try shellac before nitro. Shellac is comfortable, non-toxic, predictable, beautiful, forgiving, relatively cheap, available and easy to apply. My biggest problem with the stuff is that it takes frigging forever to really harden up. Sure it looks hard and will take a polish in a couple weeks after you are done, but takes a couple months (in my climate at least) to really harden up enough to take fingernails and other insults and even then it can be a bit fragile.

I'm currently looking at some of these modern urethanes which I always dismissed as coffee table top plastic crap. Very interesting... I hated nitrocellulose from the get go. It makes a hellava good finish. Tough, durable and musically sound. But you have to wear a respirator and it will orange peel on you bad if you get the temperatures wrong and it is a fire hazard. The stuff works a champ if you have the set up and the experience. But that is the problem: Getting the proper set-up and getting the experience.

Below directions for applying rattle-can nitro:

http://www.stewmac.com/How-To/Online_Resources/Learn_About_Instrument_Finishing_and_Finish_Repair/ColorTone_Aerosol_Finishing_Kit_Instructions.html

mikeyb2
11-23-2017, 11:03 PM
thanks everyone, but the main reason I wanted to try nitro is for it's protective qualities. I don't believe shellac would give the protection I'm looking for, although slightly better thanTruoil, so I ruled that out. Maybe acrylic laquer would be ok, I don't know. I still want to experiment with nitro, once I understand what needs to be done.
Thanks for the link sequoia.

Wildestcat
11-24-2017, 02:10 AM
Hi Mike. I've edited this post to remove the reference to a specific acrylic aerosol lacquer - it transpires that after a while, the finish on spruce tops began to craze. :(

The reference to the organic vapours mask is still valid though - I use one myself.

Screwfix offer the 3M 4251 mask for £22.

nic579
11-24-2017, 05:08 AM
I have used the Mohawk stuff doing furniture restoration it's as good as any other can spray out there and like any other you will have mixed results which can vary from can to can. Strap the can to a long dull sawzall blade and shake very well.

I would use flake shellac first personally.