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Buffed through the finish
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Author:  bcombs510 [ Fri Feb 12, 2016 12:31 pm ]
Post subject:  Buffed through the finish
Hello,

I really love learning all these lessons the hard way. Building this critical library of experience that will make good stories 5 years down the road. :D

OK, here is my setup:

1) Body was pore filled with z-poxy.
2) Applied 8 coats of Enduro-Var with an Earlex sprayer. I slightly leveled with 400 grit between coats 4 and 5. I waited 2-3 hours between coats and the guitar was hanging in a room with a heater keeping the room around 75 degrees.
3) After all 8 coats were applied I let the body sit for a week.
4) Last night I level sanded with 400 (about 95% of the shiny was gone) and then moved to the buffer.
5) Buffing plan is 4 grits Menzerna 113GZ, P204, GW16, ATOL6. This was from a thread here and worked well on another body that I buffed recently.

This was working pretty well, but I must have not been paying attention, or the finish was thin, or , or, or..... but I went through the finish and into the epoxy. [headinwall]

What is the next step? Should I sand back to wood and epoxy, finish again? Should I scuff sand the back and spray some more finish on it? The area is about 1 inch by 3 inches.

Here is a pic, but it's hard to see:
Attachment:
IMG_0242.JPG


Any help is appreciated!

Thanks!
Brad
Author:  Quine [ Fri Feb 12, 2016 1:05 pm ]
Post subject:  Re: Buffed through the finish
Uhg...I almost always sand through on the first try. I haven't used Enduro Var before, but I would just spray more over the sand-through areas. The pore filler will still be in the pores and its not tinted so you should be fine. Just make sure you clean out any dust from the polish.
Author:  Pat Foster [ Fri Feb 12, 2016 1:13 pm ]
Post subject:  Re: Buffed through the finish
If you didn't burn through the epoxy, re-spraying should be OK. Z-poxy does have a tint, so if you did go through it, the fix could show.

Pat
Author:  Joe Beaver [ Fri Feb 12, 2016 1:17 pm ]
Post subject:  Re: Buffed through the finish
I agree with Kevin.

I also am not experienced with Enduro but you may want to check with the manufacture to see if they have any hints on how to improve cross linking.

Otherwise I'd degloss the surface with 600 or 800 grit sandpaper and shoot 8 more coats on the bad area. After you get it buffed out if no witness lines great! If you do have witness lines or if experienced people say you will then I would degloss the entire back and respray it.
Author:  bcombs510 [ Fri Feb 12, 2016 1:30 pm ]
Post subject:  Re: Buffed through the finish
Thanks, all. I don't mind hitting the entire back again if that will lower the possibility of witness lines.

Thanks for the feedback! I was mentally prepared to take it back to wood, so this is actually a relief! :)
Author:  Rod True [ Fri Feb 12, 2016 2:39 pm ]
Post subject:  Re: Buffed through the finish
8 sprayed coats seems pretty thin before level sanding.....mind you we are trying to keep it thin once all done.

As for the repair, you'll probably want to spray at least 5-6 coats on the back again. You'll get some orange peel to have to worry about when level sanding again... More coats are better when "learning".
Author:  bcombs510 [ Fri Feb 12, 2016 3:01 pm ]
Post subject:  Re: Buffed through the finish
Thanks, Rod. With that in mind, should I scuff sand the entire guitar and spray more coats? I did 4 on the top alone before doing 8 more on the whole thing. But if the sides will be too thin and I have to spray anyway, maybe I'll just go ahead and spray 4-6 more coats on the whole thing.


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Author:  B. Howard [ Sat Feb 13, 2016 8:04 am ]
Post subject:  Re: Buffed through the finish
If you didn't hit bare wood you are OK. What to do next depends on where you are in your buffing. If you are in the final two stages of polishing you do not need to re-coat the entire guitar if you do not want to. You can simply scuff and tape off the back and respray it. The finish will blend well at the edge and not leave any real noticeable witness line. If you are only in the first two stages you should consider respraying the entire body as you may well find other thin spots as you progress.
Author:  ernie [ Sat Feb 13, 2016 10:34 am ]
Post subject:  Re: Buffed through the finish
FWIW I followed greven/s advice and layed on 4 coats of enduro var with a brush, he then levels off the finish with 2-3 sprayed coats before buffing and polishing.
Author:  bcombs510 [ Sat Feb 13, 2016 11:02 pm ]
Post subject:  Re: Buffed through the finish
B. Howard wrote:
If you didn't hit bare wood you are OK. What to do next depends on where you are in your buffing. If you are in the final two stages of polishing you do not need to re-coat the entire guitar if you do not want to. You can simply scuff and tape off the back and respray it. The finish will blend well at the edge and not leave any real noticeable witness line. If you are only in the first two stages you should consider respraying the entire body as you may well find other thin spots as you progress.


Thanks, I'm going over the whole body now with 8 more coats, just to be sure.

Question, I'm following your menzerna schedule from another thread and I have a question about the buffing duration.

I'm planning to take the finish down with 400 grit to mostly level, 90%+ of the shiny gone. My questions:

1) How long should I expect to spend with the lowest grit menzerna?

2) how often do I recharge the buffer?

So far I've been loading up the buffer with compound between each pass of the whole body. About 5 seconds of loading the compound, then buff the entire body, then load more compound. Is that too often or too seldom?

Thanks!
Brad


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Author:  B. Howard [ Sun Feb 14, 2016 8:30 am ]
Post subject:  Re: Buffed through the finish
bcombs510 wrote:

Question, I'm following your menzerna schedule from another thread and I have a question about the buffing duration.

I'm planning to take the finish down with 400 grit to mostly level, 90%+ of the shiny gone. My questions:

1) How long should I expect to spend with the lowest grit menzerna?

2) how often do I recharge the buffer?

So far I've been loading up the buffer with compound between each pass of the whole body. About 5 seconds of loading the compound, then buff the entire body, then load more compound. Is that too often or too seldom?


With another 8 coats I would sand until it's completely flat with no shiny spots, you will have plenty of finish maybe even a bit too much.

1) How long should I expect to spend with the lowest grit menzerna?

You will spend the longest time on this compound with each successive compound taking bit shorter time to do it's job. If your buff is completely broken in i would expect about 30- 45 minutes on the maroon compound.

2) how often do I recharge the buffer?

So far I've been loading up the buffer with compound between each pass of the whole body. About 5 seconds of loading the compound, then buff the entire body, then load more compound. Is that too often or too seldom?

You are not using enough compound. It is the compound that does the buffing not the wheel. I typically load it about 3 seconds and will buff an area about the size of 1/3 of the back or top with it and reload. Pay attention and you will see when the wheel starts to run dry. Getting the right amount of compound is something that will come with experience. A good indicator of if you are using to much or too little compound is how your buff looks after buffing. It should not be clean and free of compound but not be caked with it either, a nice light reddish color is correct..
Author:  bcombs510 [ Sun Feb 14, 2016 8:38 am ]
Post subject:  Re: Buffed through the finish
Great. Thanks for the feedback. I plan to finish spraying today and level / buff next weekend. Thanks for the help!


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