fitting the bridge feet?

jonas · #1 07-10-2004, 02:06 PM

I usually use the "sandpaper"-way, when I fit a new bridge: I attach a sheet of sandpaper to the top, and slide the bridge feet over the sandpaper until thy fit the carvature of the top.
But I know that there are some more traditional ways: using carbon paper, knife and/or plane. Which method do you guys prefer? I've never used anything other than sandpaper for the bridge feet, so I'm courious to hear some comments ...
Jonas

Bob Branstetter · #2 07-10-2004, 03:29 PM

Quote:

Originally Posted by jonas

But I know that there are some more traditional ways: using carbon paper, knife and/or plane. Which method do you guys prefer?

Set the bridge blank so that it is centered equally between the ff hole notches. Place a lead pencil on it's side and mark the bridge with the contour of the top from the fingerboard side. Use a band saw or scroll saw to cut the excess below the pencil line off the legs. Lightly tape a piece of carbon paper to the top. Place bridge on top of carbon paper (check the position again) and move the bridge forward and back in very short increments (less than 1/16") while making sure you keep the bridge from tilting. Remove the high spots with very sharp knives. I keep a few knives sharpened with a gentle curve on the cutting edge so it can be used like a mini wood scraper where needed. Repeat process until carbon is transferred uniformly on the feet. If needed, use some very fine sandpaper to remove the carbon traces when finished. That's how I do it.

arnoldschnitzer · #3 07-11-2004, 06:32 PM

I like lipstick. I prefer a bright red, as it sets off my hazel eyes... I like to trim the feet with a nearly-flat palm gouge, then a tiny round-bottom plane, then scrapers. Works for me. BTW, when centering the bridge, odds are if you sight down the neck you'll see more bridge on one side than the other. This could be due to an off-center neck, uneven top settling, or a bass built a bit asymmetrically. You may have to cut one foot of the bridge a bit longer to compensate if this is the case. Anyway, give up on the sandpaper routine. It doesn't work with any reasonable degree of accuracy.

Marcus Johnson · #4 07-11-2004, 07:49 PM

[quote=arnoldschnitzer]I like lipstick. I prefer a bright red, as it sets off my hazel eyes...

Ah, it's nice to know that my bass was built by a very, very sick man.

Jeff Bollbach · #5 07-11-2004, 10:42 PM

[quote=Marcus Johnson]

Quote:

Originally Posted by arnoldschnitzer

I like lipstick. I prefer a bright red, as it sets off my hazel eyes...

Ah, it's nice to know that my bass was built by a very, very sick man.

Not that there's anything wrong with that.
Arnold got me into using lipstick as well. I still use a china marker sometimes but the stick has certain advantages. One big one is that anytime you are fitting two parts thru a transfer method the less movement in making the transfer the better. If you are using sandpaper or carbon paper you need to move the bridge in order to abrade or pickup a marking. It's easy to rock the part and get a false transfer this way. In addition if you move the part you are moving it away from where it needs to fit and this can lead to inaccuracies. If one uses lipstick the bridge[or any fit part] can be placed right on the mark and the transfer occurs immediately due to the nature of the lipstick. It gives a very accurate reading.

Bob Branstetter · #6 07-12-2004, 12:17 AM

I agree with Arnold and Jeff about the advantages of using lipstick to get no movement contour transfers and I have in fact tried it with success. However, many of the basses I have come into my shop have little or no finish remaining on the top in the area where the bridge feet touch. I worry about the possibility of getting bright red lip stick into the pores of the top wood where the finish is missing so I refrain from using it when that possibility exists. Short of doing finish touch-up, how do you prevent this from happening? Self clinging plastic food wrap? If there is a way to accomplish this, I would like to hear about it since lip stick does give very accurate contour transfers while fitting the feet.

**Chris Fitzgerald** · #7 07-12-2004, 07:42 AM

Quote:

Originally Posted by Marcus Johnson

Quote:

Originally Posted by arleneschnitzer

I like lipstick. I prefer a bright red, as it sets off my hazel eyes...

Ah, it's nice to know that my bass was built by a very, very sick man.

...also explains why mine showed up in a fishnet case. Yes, it all makes sense now.

jonas · #8 07-12-2004, 05:24 PM

Quote:

Originally Posted by arnoldschnitzer

Anyway, give up on the sandpaper routine. It doesn't work with any reasonable degree of accuracy.

In most cases, sandpaper works absolutely fine for me ... no problem with the accuracy. But it's important to simulate the strings' pressure, by wedging a piece of wood (an old soundpost, cut to proper length) between the bridge legs.
However, I like the lipstick trick and will try it.

Bob Branstetter · #9 07-12-2004, 05:46 PM

Quote:

Originally Posted by jonas

In most cases, sandpaper works absolutely fine for me ... no problem with the accuracy.

Why don't you try using the lip stick AFTER you've fitted with sandpaper just to see if your fit is really as accurate as you think it is. I've used leg spreaders on cello bridges for years, but I've never found it necessary on high quality bass bridges. However, I suppose that forcing the legs apart would help you with the sandpaper method since it would force you to remove more wood from the inside of the legs to make up for the errors on the outside from rolling.

godoze · #10 08-04-2004, 12:39 PM

Le me get this straight (first let me do my eyebrows)... You are putting lipstick on the feet and then putting the bridge straight down on the table ?

Brent Norton · #11 08-04-2004, 01:07 PM

I've never used the lipstick technique, but I'd assume you have to apply it to the top, not the bridge -- applying it to the bridge feet would defeat the purpose...

godoze · #12 08-04-2004, 01:14 PM

that makes sense...

**Damon Rondeau** · #13 08-04-2004, 05:24 PM

Your dentist uses the same type of technique when he's testing whether a filling is too high, or in fitting a crown. My own dentist is kinda old school -- he uses ordinary carbon paper.

Knowing how to do this sort of thing is one of the official mysteries of the luthier trade, IMO. It's really not very common in cabinet-making or general woodworking.

nicklloyd · #14 08-05-2004, 07:37 PM

I use lipstick, a 1" Japanese chisel, and a small bevelled scraper. Knives are great, too. Sandpaper should only be used if you live on an island, and can't get anything else to use. Sandpaper, as a hand tool, is best used for blending and smoothing a previously cut surface.

If there is unvarnished spruce in the bridge-foot area, touch-up the area with some clear first, then use the lipstick. Windex will remove the lipstick later.

**Damon Rondeau** · #15 03-26-2005, 10:32 AM

I was looking for some other stuff but started looking through this old thread.

I've found that this bent knife is sublime for fitting bridge feet.

Wil Davis · #16 03-26-2005, 12:09 PM

Cool site - nice tool - thanks for the link…

- Wil

Marty Forrer · #17 03-28-2005, 02:52 AM

At the risk of incurring the derision of those more knowledgeable, I have always done my own feet using the sandpaper method. After reading this and other posts on the luthiers methods, I decided to check my feet again. I used the carbon paper method, and my feet were perfect. I think the secret to getting a good result with sandpaper is to pull the bridge in one direction only, and to pull in small movements, say one centimetre. When the job is done, a few sideways passes towards the f-holes, once again in small increments, will straighten up any rolling that may have occurred. Not trying to be a smart**s here, but the nearest luthier to me is 4 hours drive, so I naturally try to do all my own stuff where possible.

nicklloyd · #18 03-28-2005, 09:33 AM

Well, it seems that you do live on an island (New Zealand)... so sand away!

Ben Joella · #19 03-28-2005, 10:38 AM

Quote:

Originally Posted by Marty Forrer

I have always done my own feet using the sandpaper method.

Ouch!

arnoldschnitzer · #20 03-28-2005, 12:09 PM

The sandpaper method might work ok on a new-ish bass with a perfect top. But it won't work on an old bass with deformations in the bridge area. Fitting to an old bass is very site-specific and you can't be sliding the bridge around much or you'll get a really sloppy fit. How about giving the contact transfer method a try sometime--it can only improve your skills...