Bridge Placement Headaches

Please put your pickup/wiring discussions in the Electronics section; and put discussions about repair issues, including "disappearing" errors in new instruments, in the Repairs section.
Post Reply
User avatar
Scott Freeman
Posts: 19
Joined: Tue May 29, 2012 2:22 pm

Bridge Placement Headaches

Post by Scott Freeman »

So I tried searching all reaches of the internet but could not find a good answer to these questions: What is the best way to determine where the bridge should be placed? Where should the saddles be when measuring? Are measurements based on the saddle location of a specific string? I realize that this is critical for intonation and must be very precise. When I received the neck (yes, I actually bought the neck for my first build), there was a whole drilled to mark the 25" scale.

I have no neck angle, and the bridge that I am using is this: http://guitar-bridge.com/hp135016/Guita ... 0ad17X79ea

Any help you could provide would be greatly appreciated as I want to ensure that I have no intonation problems.
Attachments
Hole center at 25"
Hole center at 25"

User avatar
Eddie McRae
Posts: 153
Joined: Thu Feb 23, 2012 10:07 am
Location: Woodbury, GA USA
Contact:

Re: Bridge Placement Headaches

Post by Eddie McRae »

I'm sure you've noticed that all TOM-style bridges and also most wrap-arounds are mounted at an angle. Just as the saddle slot is angled in acoustic bridges. This is done to allow for intonation differences between each string. Generally speaking, the low (large) E string will be approx. an 1/8" longer than scale length and the high E will be approx. a 1/16" longer than scale length......hence the angle for TOM-style bridges. So, for example, if scale length is 25", the low E string saddle should intonate at approx. 25 1/8". Use those measurements as a guideline and make sure your saddle adjustments fall within those measurements when determining bridge location. Also, while doing this, make sure your saddles still have ample adjustment in both directions to allow room for fine tuning the intonation.

JC Whitney
Posts: 157
Joined: Mon Jan 09, 2012 1:19 am

Re: Bridge Placement Headaches

Post by JC Whitney »

A good way to double check... Stewmac.com, use their online Fret Position Calculator - I believe that your bridge is listed at the bottom of the page. Enter your scale length, etc and it will help you to locate the bridge correctly.

User avatar
Scott Freeman
Posts: 19
Joined: Tue May 29, 2012 2:22 pm

Re: Bridge Placement Headaches

Post by Scott Freeman »

Thanks guys!

Edgar Jessop
Posts: 33
Joined: Sat Jun 02, 2012 7:23 pm

Re: Bridge Placement Headaches

Post by Edgar Jessop »

All of the Carvin necks I have ever used had a neck angle built in. You can check your neck by laying a long straight edge on the frets and extend it towards the end of the body. Measure the straight edge to body-top distance at the end of the fretboard and at a point near the end of the body.

Robert Smallwood
Posts: 108
Joined: Sat Jan 07, 2012 7:33 pm
Location: Merimbula NSW Australia

Re: Bridge Placement Headaches

Post by Robert Smallwood »

I have an old trapeze tailpiece. with this attached i make sure the E1st & E 6th strings intonate. Basically I measure down the string on the E 1st with the saddle 2/3 - 3/4 forward to start with and move the bridge slightly until both E's intonate properly. For string throughs I have a metal plate with 6 holes in it that takes the place of ferrules for stringing up the e 1st & E 6th.

Jeff Mills
Posts: 70
Joined: Tue Feb 07, 2012 12:49 pm

Re: Bridge Placement Headaches

Post by Jeff Mills »

Robert Smallwood wrote:I have an old trapeze tailpiece. with this attached i make sure the E1st & E 6th strings intonate. Basically I measure down the string on the E 1st with the saddle 2/3 - 3/4 forward to start with and move the bridge slightly until both E's intonate properly. For string throughs I have a metal plate with 6 holes in it that takes the place of ferrules for stringing up the e 1st & E 6th.
Thanks for this nugget, I was using a custom made "story stick" cut to exactly the scale length with a centering hole over where the bridge would go. with one end of the stick on the inside edge of the nut. I ran the saddles all the way up (twords the nut) and marked the bridge position to the end (butt) of the notches in the saddles with the other end of the stick. I was always concerned I would run out of saddle adjustment bringing them all the way forward like that. But it seems that I always have to run the saddle back 4 or 5 turns to intonate. Now I know I can leave myself a little wiggle room and not run the saddles all the way up to begin with.

Thanks
Experience is a strange thing - You get it right after you needed it.

Paul E Buerk
Posts: 66
Joined: Sun Jan 08, 2012 10:25 pm

Re: Bridge Placement Headaches

Post by Paul E Buerk »

A good way to double check... Stewmac.com, use their online Fret Position Calculator
Usually. However, I've had a case recently where the distance given by the calculator for the Hipshot through-body hardtail bridge was too close to the neck. I violated one of my own rules by not doing my own calculation and drawing to make sure, simply relying on the StewMac calculator. It ended up being adjustable enough so that I could intonate properly, but going with any heavier strings would result in having to trim the springs a bit, and it looks kinda goofy with that much bridge plate showing in front of the saddles. If it had been a top loader and not a through body bridge, I could have simply plugged, re-drilled, and moved the bridge, but that wouldn't work because of the ferrules.

I've tried using a spreadsheet based on an article on Compensation calculation posted in "American Lutherie", but for some reason I can't get the results to agree with what's in the article. I may have posted about this before on the old MIMF forum, but to date I haven't seen any other comments about it. If it worked like I'm sure it does, then you could use it to do the calculations for you and assist with your bridge layout.

Post Reply