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View Full Version : Little Help Please (tuners and bridge)



MichaelPfenning
02-23-2015, 03:46 PM
I was going to drill the holes for the tuners and I realized my tuners aren't long enough. I Purchased the tuners with the longer post 25mm but the peg head is 20mm thick. I don't know what to do next. I could mortice the tuners down into the back of the peg head. I could thin the whole head down from the back side and taper it into the neck. The Second question is. If my scale length is 15 inches do I place the saddle exactly 15 inch from the nut or would 15 3/32 be better ? and can I glue the bridge down and finish ( using Tru-oil) or do I have to tape it off and glue it later. Sorry for the length of this post. Any help would be appreciated. 7649876499

Michael Smith
02-23-2015, 04:25 PM
I would thin the back of the headstock down. It's hard to see from the photos but it looks like your neck might be pretty thick. If you make the neck too thick your left hand will tire more quickly when you are playing. 3/32 is about right for the center of your saddle. If you are using a 1/8th saddle you can then compensate a little in either direction. You can glue the bridge down first but it is harder to get over glue off unfinished wood cleanly. Having said that I would rather use an oil finish with the bridge already glued on than lacquer. Most of us do our finishing then route or scrape off the finish under the bridge. I put some painters blue tape where the bridge will go, locate the bridge, draw around the bridge with a sharp pencil onto the tape, then with a sharp scalpel cut 1/16th inch inside that line, remove the tape in that area leaving the tape on the outside to protect the top while removing the finish with a ver small chisel. You can also certainly locate your bridge, and use the same method to leave a piece of tape for masking then finish. I don't know why I don't do it that way. It would be quicker. I have read from those who do it that way if you are spraying lacquer it's best to use a very thin tape like wide clear tape that most use on hand held tape dispensers.

mzuch
02-23-2015, 04:50 PM
1. Thin the back of the headstock if tuners don't fit. LMI sells uke tuners with adjustable posts, but you'll need to check the specs to see if they'll work.

2. 3/32 is about right for saddle compensation, but check a fret placement calculator for more precise measurement.

3. Whether to mask the bridge area before finishing is a matter of personal preference. I finish the entire soubdboard, then remove lacquer under the bridge using a handheld router.

These are all good questions, and all issues I faced on the climb up the learning curve. Fortunately, the answers can be found online and offline by reading and viewing as much as you can.

sequoia
02-23-2015, 06:47 PM
I finish the entire soubdboard, then remove lacquer under the bridge using a handheld router.

To me this method sounds unnecessary and potentially disastrous. After I'm done lacquering, the last thing I want to do is go after my top with a router. Plus it is unnecessary. Here is how I do it:

After final sandout and before finishing, put down a big old piece of 2 inch painter tape across your top in the approximate position of where your bridge is going to be go leaving lots of extra room. 3/32 over 15 sounds about right but personally I would cheat closer to a 1/16th but what do I know?... Next, measure off your bridge position very carefully both distance and exactly parallel to your nut on both ends. When satisfied, draw a pencil line around your bridge onto the tape. Next cut out the pencil line with an exacto knife about 1/16th inside the line. Peal off the tape around the outside and you now have a perfect mask for your bridge. No sharp routers needed and you will have perfect bare wood for gluing after you have done your finish. After finish just remove the tape and remeasure and then glue bridge.

MichaelPfenning
02-23-2015, 07:38 PM
Headstock cut down and the neck has been tapered to match. Thanks for the help. I taped the sound board and cut around the bridge with a sharp knife.

Allen
02-23-2015, 07:49 PM
Your tuners are not too short. Your peg head is way to thick.

Depending on the exact tuners, your peg head with head plate should be between 10.5mm and up to perhaps 12.5mm thick. There will be a bushing that came with those tuners that needs to be pressed into a counter bore of the face side of the headstock as well.

If you look at the shaft on the tuners there are two lines. I'd take a rough guess and say that the overall thickness of your peg head should be the just a bit more as the distance from the backing plate to the top line. Then with the bushing thickness you are going to be pretty close.

I'd really recommend that you practice on some scrap first on getting those counter bores right if you don't have the pretty specialized tooling for the job.

As for saddle position, if you went for 15" and just a bit to the centre of the saddle you won't go far wrong. It really depends on the action, string choice, the size of frets, playing style etc.

If you are using any type of oil finish, you had best glue that bridge down first, or the risk of contaminating a surface that will never take glue is pretty high.

Kekani
02-23-2015, 07:57 PM
To me this method sounds unnecessary and potentially disastrous. After I'm done lacquering, the last thing I want to do is go after my top with a router. Plus it is unnecessary.

As Allen stated in the Out of the Box thread, chiseling/routing out the lacquer after spraying is one of those little things that solve a few bigger things. Admittedly, when I first saw Bob Gleason write about this process, I thought "no way I'm doing that." I didn't think it unnecessary, and I saw the value immediately, but was too chicken shit to attempt it. That was before I got my Foredom, and learned how to use it. Helps that I have the bits for it as well.

Of course, with an Oil finish, I'd tape it, or other.

Michael Smith
02-23-2015, 08:07 PM
Wait, you want to under cut the shape of the bridge by a 1/16 or so. You don't want to have your masked area the same size as the bridge. It must be smaller. When you are done with your finish cut around it again so you don't pull your finish up when removing the mask.



Headstock cut down and the neck has been tapered to match. Thanks for the help. I taped the sound board and cut around the bridge with a sharp knife.

Moore Bettah Ukuleles
02-23-2015, 08:33 PM
As Allen stated in the Out of the Box thread, chiseling/routing out the lacquer after spraying is one of those little things that solve a few bigger things. Admittedly, when I first saw Bob Gleason write about this process, I thought "no way I'm doing that." I didn't think it unnecessary, and I saw the value immediately, but was too chicken shit to attempt it. That was before I got my Foredom, and learned how to use it. Helps that I have the bits for it as well.


Of course, with an Oil finish, I'd tape it, or other.

I've used this method for years, showed Bob and many others how to do it safely. It is a very controlled process with less chance of screwing up than using a hand scraper or more primitive methods. A few months ago I did a pit oral of how it's done. I'll see if I can dig it up. BatW, I see no advantage to the Foredom. I have one but find the movement cumbersome because of the shaft you are tethered to. Instead I use a Dremel in my StewMac base.

mzuch
02-24-2015, 04:20 AM
I see no advantage to the Foredom. I have one but find the movement cumbersome because of the shaft you are tethered to. Instead I use a Dremel in my StewMac base.

I like my Foredom much better than a Dremel. Advantages: 1) Variable speed control through a foot pedal, and 2) It's always there when I need it, hanging from the tree attached to my bench instead of sitting in a drawer.

resoman
02-24-2015, 05:22 AM
I was in the same boat as Kekani as I didn't the guts to try Chuck's method even tho I had a StewMac Dremel base for a couple of months before I finally gave it a try. I am never going back to the old scraping method again!
Like the others,if I was going to use oil I'd stick the bridge down first.

Wildestcat
02-24-2015, 06:29 AM
Wait, you want to under cut the shape of the bridge by a 1/16 or so. You don't want to have your masked area the same size as the bridge. It must be smaller. When you are done with your finish cut around it again so you don't pull your finish up when removing the mask.

Hi Michael, I have to confess I don't really understand why it is essential to undercut the shape of the bridge, thus leaving a finish ridge under the bridge edge which will not make a decent bond with wood glue (Titebond in my case) and will leave a less than perfect glue-able area.

I learned this method from my time with Pete Howlett a while back (not sure if Pete still does it though). The bridge is located on the unfinished top and two 2mm holes drilled through the saddle slot to take pieces of 2mm plastic rod to act as dowels for positive re-location. I then tape over the area with what we in the UK we call "parcel tape" the very thin brown sellotape-like stuff. The bridge is then re-positioned on the top using the 2mm dowels and I gently scribe round with a brand new No 11 scalpel. The excess tape is peeled away to leave a precise bridge outline. I apply my Tru-oil finish over the tape. I also sand right over the tape - it is so thin this works fine. After the finish is done, the tape is carefully removed by scribing round its edge with a new No11 blade and carefully peeling back. I clean up any tape adhesive residue with white spirit (naptha in the US?). A slight downside is the thin tape usually comes away in sections, but the scalpel can be used to gently lift edges and achieve clean removal. There is no damage at all to the edge of the finish. After glueing on the bridge, there is an excellent fit and no visible gap or finish damage. I much prefer this method (I have used both), as I don't really warm to the idea of an effectively unglued bridge edge.

Is the reason many pro builders recommend leaving 1.5 mm of finish around the edge to ensure they get an invisible joint every time, or am I missing something else?

Moore Bettah Ukuleles
02-24-2015, 08:13 AM
Here's a series of photos showing my method of lacquer removal.

Moore Bettah Ukuleles
02-24-2015, 08:19 AM
The finished product waiting for the bridge to be glued on.

Masking the bridge area doesn't work for my finishing schedule because of the "lump" it forms, making sanding and buffing difficult.
With scraping you never know when you are getting all the lacquer off or scraping too much wood. It's also very slow and I worry about slipping and marring the finish.
Routing only hurts the first time you do it. After that it's easy, safe, precise, clean and quite fast. As with any work concerning most of what we do, you need to have a steady hand and focussed concentration.

Allen
02-24-2015, 09:38 AM
That method works just fine Paul, but as Chuck mentions, you can get a ridge of finish if you are using a type that builds right on the masking line. Especially when going through two or three spray sessions of lacquer to get a mirror like finish.

In this case its far better to finish without masking, and then remove afterwards. Either scraping or using the dremel.

Michael Smith
02-24-2015, 04:01 PM
That is the reason I leave about 1.5mm of finish. If your way can do it with a perfect cover with the bridge than that's the way to go. I mostly use nitro and don't think I could pull a mask that was exactly the same size as the bridge without problems, though I must admit I have never tried and probably never will. I do it the same way Chuck has just demonstrated less using the router for the removal. I want that 1/16 inch for any little twirk or bip in the lacquer when you cut loose the mask if using a mask.


Hi Michael, I have to confess I don't really understand why it is essential to undercut the shape of the bridge, thus leaving a finish ridge under the bridge edge which will not make a decent bond with wood glue (Titebond in my case) and will leave a less than perfect glue-able area.

I learned this method from my time with Pete Howlett a while back (not sure if Pete still does it though). The bridge is located on the unfinished top and two 2mm holes drilled through the saddle slot to take pieces of 2mm plastic rod to act as dowels for positive re-location. I then tape over the area with what we in the UK we call "parcel tape" the very thin brown sellotape-like stuff. The bridge is then re-positioned on the top using the 2mm dowels and I gently scribe round with a brand new No 11 scalpel. The excess tape is peeled away to leave a precise bridge outline. I apply my Tru-oil finish over the tape. I also sand right over the tape - it is so thin this works fine. After the finish is done, the tape is carefully removed by scribing round its edge with a new No11 blade and carefully peeling back. I clean up any tape adhesive residue with white spirit (naptha in the US?). A slight downside is the thin tape usually comes away in sections, but the scalpel can be used to gently lift edges and achieve clean removal. There is no damage at all to the edge of the finish. After glueing on the bridge, there is an excellent fit and no visible gap or finish damage. I much prefer this method (I have used both), as I don't really warm to the idea of an effectively unglued bridge edge.

Is the reason many pro builders recommend leaving 1.5 mm of finish around the edge to ensure they get an invisible joint every time, or am I missing something else?

Wildestcat
02-25-2015, 09:20 AM
Thanks chaps. I'm in the process of trying a brushed waterborne lacquer finish instead of Tru-oil, so I'll see how I get on!