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Mask off before finishing or remove finish after
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Author:  weslewis [ Thu Jun 20, 2013 8:13 am ]
Post subject:  Mask off before finishing or remove finish after

What is the prevailing method for bridges and fretboard extensions????

idunno idunno idunno

Author:  B. Howard [ Thu Jun 20, 2013 8:18 am ]
Post subject:  Re: Mask off before finishing or remove finish after

I generally don't mask them. I find the tape gets in the way of level sanding and buffing. I rout the lacquer off down to the sealer and then scrape off the sealer.

Author:  Tony_in_NYC [ Thu Jun 20, 2013 9:03 am ]
Post subject:  Re: Mask off before finishing or remove finish after

I don't mask because I don't locate the bridge until after I have buffed the finish and made sure the neck fits perfectly after is has finish on it as well. Thus, I scrape it off. I am not a big fan of scraping it off, but I prefer to locate the bridge after all of the finishing has been done, so I don't have much of a choice now, do I?

Author:  gozierdt [ Thu Jun 20, 2013 9:39 am ]
Post subject:  Re: Mask off before finishing or remove finish after

I've tried both masking and scraping. Both have their own advantages, but both have
disadvantages as detailed above. I've just made the jigs for routing a small undercut
around the edges of the bridge, and routing off the finish leaving .001-.0015 gap under
the bridge for glueline. I'll be using them on two guitars later this week. I don't see any
disadvantages to this method, other than cost/time to make the jigs, and getting depth
control dialed in.

Author:  ernie [ Thu Jun 20, 2013 9:54 am ]
Post subject:  Re: Mask off before finishing or remove finish after

"+1 tony, finish first, masking can be a pita.

Author:  Burton LeGeyt [ Thu Jun 20, 2013 10:16 am ]
Post subject:  Re: Mask off before finishing or remove finish after

I mask. I'm surprised to hear that people don't like it, I find it pretty simple.

I use the Friskit film. I'll put layers on the body around the neck to simulate a film thickness when setting the neck prior to finishing to more accurately locate the bridge. The film is .03 or so so can also be used to gauge your final film thickness at the bridge area when level sanding.

Joe always asked me to mask off slightly smaller than the bridge when I sent guitars to him and I still do that. Once the guitar is buffed I lightly score around the bridge with an exacto and a sharp chisel pops the little bit of leftover finish right of, leaving a perfect opening for the bridge. That part is pretty simple too, just requires a few anal moments with the chisel.

I could never figure out how to make the ledge exact enough. I figured it was either going to show a small gap or not make a good glue joint at the edges. Not that it doesn't work, I just wasn't confident of the method.

Author:  ChuckB [ Thu Jun 20, 2013 11:04 am ]
Post subject:  Re: Mask off before finishing or remove finish after

I mask mine off like Burton, slightly smaller than the bridge. The Frisket film I use is .001 thick, so you can level the finish right over the masked area.

Chuck

Author:  jfmckenna [ Thu Jun 20, 2013 12:22 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

Same as Burton for me too. I can't imagine placing a router near a finished guitar eek

If you make it slightly smaller it also gives you the advantage of tweaking the location. If you need to tweak it anymore then that imho you've made a worse error. Also by making it slightly smaller you can buff it out and the finish-to-tape line that it makes will simply be cut out.

Author:  Colin North [ Thu Jun 20, 2013 1:20 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

Undersized Frisket film, 1 thou, matt, extra tack was recommended in a thread here on OLF.
I tried it on my last finish, and after a few coats the thickness just disappeared as I sanded/levelled/buffed, but the matt of the film could still be seen making removal a breeze.
I'm a convert. bliss

Author:  Joe Beaver [ Thu Jun 20, 2013 2:59 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

I've been using masking tape under the bridge and the FB extension. The Frisket sounds very good. Thanks guys.

One question, where do you buy it? Art store? Hobby store?

Author:  Terence Kennedy [ Thu Jun 20, 2013 3:17 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

I do the same as B Howard. Rout and scrape as well as sand with small blocks. Just did two. I'm another guy that does not like locating the bridge until the final neck position is known.

Author:  Fred Tellier [ Thu Jun 20, 2013 5:22 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

+1 for Friskit film.

Fred

Author:  weslewis [ Thu Jun 20, 2013 8:09 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

I have been at work all day, interesting responses....another question , does anyone apply finish to the bridge?????

Author:  Tony_in_NYC [ Thu Jun 20, 2013 8:14 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

Classical guys do. Sometimes.

Author:  Joe Beaver [ Thu Jun 20, 2013 9:35 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

As Tony said, many classical builders finish the neck with the body after it has been attached, and some may do the same with the bridge. I don't. On SS I cheat tradition (meaning the Martin way) and put a little oil finish on the bridge to seal it.

Author:  Jim Watts [ Thu Jun 20, 2013 9:56 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

Another one here using slightly undersized frisket. Routing seems so appealing but I just can't get the confidence to take a router to a finished instrument. Maybe one day.

Author:  Randolph [ Thu Jun 20, 2013 10:44 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

Friskit film source? :-)

Author:  Jim Watts [ Thu Jun 20, 2013 11:40 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

Randolph wrote:
Friskit film source? :-)

A good art supply store.

Author:  Terence Kennedy [ Fri Jun 21, 2013 12:02 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

Jim Watts wrote:
Another one here using slightly undersized frisket. Routing seems so appealing but I just can't get the confidence to take a router to a finished instrument. Maybe one day.


I learned it at the Fox course in 2004. My rig is a StewMac Dremel base with a 1/8" spiral downcut bit. Cork on the bottom of the base. (Charles used felt) Mask off the top with low tack drafting tape and score the bridge outline as usual and score another line 1/32" inside. That's the line I rout to and clean up the edge with a chisel.
You can creep up on the depth pretty easily so you just skim the top wood. The cork or felt allows you to vary the pressure and depth a smidgen. Scrape and sand afterwards.

You have to really be careful to square off the corners of the wings so residual finish does not prevent contact and make sure ALL the sealer is off.

Still takes me 2 hrs from start to having the bridge undercut prepped and clamped up and I've done it over 50 times. Still gets my heart rate up a bit but no disasters so far.

I'd be interested in more detailed descriptions of other's router technique and also the Friskit technique.

Image

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Author:  Ken C [ Fri Jun 21, 2013 8:12 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

I mask and find it very simple. I use two layers of wide blue painters mask. When I am done spraying, I remove the top mask, which allows me to easily level and buff. I then pull the last mask, clean up the area for a good fit, scrape with a razor blade and glue on.

Ken

Author:  weslewis [ Fri Jun 21, 2013 9:59 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

Ken are you masking slightly smaller than the bridge????

Author:  Mitch Johnson [ Fri Jun 21, 2013 11:55 pm ]
Post subject:  Re: Mask off before finishing or remove finish after

If ever using tru oil on a top...Mask first!

Author:  flounder [ Sat Jun 22, 2013 2:40 am ]
Post subject:  Re: Mask off before finishing or remove finish after

Colin North wrote:
Undersized Frisket film, 1 thou, matt, extra tack was recommended in a thread here on OLF.
I tried it on my last finish, and after a few coats the thickness just disappeared as I sanded/levelled/buffed, but the matt of the film could still be seen making removal a breeze.
I'm a convert. bliss


Hi Colin,
Where do you get your extra tack film from in the UK?

Author:  Ken C [ Sat Jun 22, 2013 10:40 am ]
Post subject:  Re: Mask off before finishing or remove finish after

Hi Wes,

I actually put two layers of tape down on a cutting mat, lay the bridge on top and cut out the shape with an exacto knife. I'm not cutting any smaller. But I do occasionally have a little clean up to do with an exacto knife and chisel when done. I've been using this approach for the last several years with no issues.

After spraying finish, I simply remove the top layer of tape. Final film thickness prior to final leveling and buffing can also be done by throwing a caliper on the top layer of tape:
Attachment:
DSCN3980.jpg

This leaves a slight ridge at the seam, which can now easily be leveled and buffed without worry of contaminating the spruce underneath:
Attachment:
DSCN3983.jpg

All buffed out:
Attachment:
IMGP1202.jpg

A little scraping with a razor blade, some clean up, and ready for the bridge:
Attachment:
IMGP7888.jpg

Bridge is on and fits neatly in the masked area:
Attachment:
IMGP1315.jpg

As you have seen, lots of ways to go about it, but this approach for me is very simple and has worked well. The trickiest part is cutting the mask. I always cut the mask and locate it on the guitar, then I double check by placing the bridge on the mask to make sure I haven't stretched the tape. It's pretty easy to remove lacquer, a little hard to add if the mask has been cut too large.

weslewis wrote:
Ken are you masking slightly smaller than the bridge????

Author:  weslewis [ Sat Jun 22, 2013 10:56 am ]
Post subject:  Re: Mask off before finishing or remove finish after

Actually on my last one I used frisquit

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