Official Luthiers Forum!

Owned and operated by Lance Kragenbrink
It is currently Sun Apr 20, 2025 5:45 pm


All times are UTC - 5 hours





Post new topic Reply to topic  [ 5 posts ] 
Author Message
 Post subject:
PostPosted: Mon Mar 28, 2005 5:11 am 
Offline
Brazilian Rosewood
Brazilian Rosewood
User avatar

Joined: Mon Dec 27, 2004 3:50 pm
Posts: 4662
Location: Napa, CA
Based solely on Mario's recommendation some months ago, I bought a quart of the glossy stuff and recently used it for the first time. Here's an account of what I did and what I learned so far. I rarely have an opportunity to contribute anything of technical value here so I was hoping to add some knowledge to the pool. It's only a start with more info to come later.

1) The surfaces (IRW and mahogany) were pore filled several times and leveled with Z-Poxy and final sanded to 320 grit. The Adirondack top was sealed with shellac sealer and sanded smooth.

2) The Target Oxford 9000 material looks milky white before and after stirring. This concerned me at first until I did a test spread on glass...it cures out clear, but not as hard as nitro...at least not after 24 hours.

3) I sprayed full strength in a cheap HVLP system that I bought from Rockler for $100. I used the smaller nozzle. It sprays nicely but lays out with a bit of orange peel. I waited a few hours, scuff-sanded and repeated spraying. Still orangy but no runs. It was a fairly thick coating by now.

4)After 3 weeks, I level sanded the orange peel surface with 320 grit on a ROS and by hand and sprayed 2 more coats...still not real smooth.

5) After 5 days, I level sanded with 400 grit and began the wet sanding process by hand. Now it became real smooth.

6) Wet sand with 400, 600, 1000, 2000 conventional grits, then MicroMesh sand from 4,000 through 12,000. It looks ok but not as reflective as nitro at the same stage. I looked at it under various lighting conditions and can see no bluish tint...it is as clear as I expected it should be.

I plan to buff out using Menzerna gradeson the wheels in 3 weeks when I return home. Hopefully it will achieve that 3 dimensional depth of shine. I'm also hoping the extra time will find it harder.

The material is a joy to work with...no fumes and it cleans up so easily with water. It is noticeably softer than nitro (possibly as it adsorbs water in the wet sanding process).

It's just a lot different feel than Nitro and will take some experience to figure it out. Any comments or questions are welcome.

_________________
JJ
Napa, CA
http://www.DonohueGuitars.com


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 28, 2005 5:33 am 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Mon Jan 03, 2005 7:40 am
Posts: 2694
Location: United States
First name: John
Last Name: How
City: Auburn
State: Ca
Country: USA
JJ, are these the Parlor pair or just some test peices?

_________________
Tickle your guitar daily, and it'll tickle you back.


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 28, 2005 5:59 am 
Offline
Old Growth Brazilian
Old Growth Brazilian

Joined: Tue Dec 28, 2004 1:56 am
Posts: 10707
Location: United States
I have not use an HVPL system but with a std compressor driven spray system Orange peel is a sign of inadequate atomization. Several things can cause it. From clogged nozzle to air volume. I use KTM-9 it may not be as hard as Nitro but cures hard enough and polishes to a great luster. I would assume the Oxford will do as well.


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 28, 2005 6:00 am 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Tue Jan 04, 2005 1:43 am
Posts: 1531
Location: Morral, OH
JJ:
I tried it too on a back of a cherry guitar. The sides and top were sprayed with nitro so this gave me a good comparison but as Mario pointed out I should not compare the two ... but it's just so hard not to.

I initially wet sanded and buffed it after a 7 day wait and it was still too soft and rubbery. I had a total of 4 coats on it. After two weeks I was able to buff it. I didn't have any problems with burn through but the finish doesn't burnish like nitro so it is quite different. I had to progress through 3 grits of Menzurna to achieve an acceptable gloss. After examining the finsh under a high powered 10X magnifier the surface appears porous unlike a glass-smooth sealed surface of nitro. I suspect the porosity refracts instead of reflects the light hence the different appearance. The average guy would not notice a difference as they are both "shiny" but nitro still has my heart.

I do like the low odor of the 9000. No off gassing fumes to be concerned with either which is a definite health advantage.

_________________
tim...
http://www.mcknightguitars.com


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 28, 2005 6:28 am 
Offline
Brazilian Rosewood
Brazilian Rosewood
User avatar

Joined: Mon Dec 27, 2004 3:50 pm
Posts: 4662
Location: Napa, CA
John...This is on #2...the 000 12 Fret. I'm still unsure as to what I'm going to finish the parlors with.

_________________
JJ
Napa, CA
http://www.DonohueGuitars.com


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 5 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 17 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group
phpBB customization services by 2by2host.com