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Hi

Can you give me some advice please

Making my own bridge from ebony block and the holes i have drilled are out a bit
The bridge is far from finished but should i continue

Heres a pic


The measurements from hole centre to centre are

E-a .430" (10.9mm)
A-d .423" (10.8mm)
D-g .422" (10.7mm)
G-b .438" (11.1mm)
B-a .404" (10.3mm)

Is this going to cause a problem with playing and feel

Drilled with 4.5mm drill bit so got a little wiggle room

Cheers

Being ebony you can plug it pretty easy and re-drill.
You can make your own plugs by gluing a piece of ebony on the end of your drill bit and chuck it in your drill and sand or file to the diameter of the bit.

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Looks like the pattern is way off center too?

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Ken Cierp

http://www.kennethmichaelguitars.com/

You can probably fix that with a needle file. Expand the B hole toward the G, so when reaming them later the center will be offset a bit that way. And use unslotted pins and slot the bridge. The slots can be used to shimmy the exit points of the strings back and forth as desired, as well as equalizing the break angle of each string over the saddle (if you care about that). As it is, the low E will have way more angle than the others.

As Ken says, the treble wing does look longer than the bass... but that shouldn't cause any problems other than visual.

I used a drilled out bridge as a guide but thinking should of done my own measuring. . Guessing from the comments its really important to be accurate with peg holes..thinking maybe getting a new blank and starting again

I've spent my whole career working with products that often need marked for drilling, tapping, screws, rivets etc in precise locations. Here are a couple things I've learned.
1) Use precise instruments when precise locations are warranted (you're using digital calipers. Good start)
2) Use the finest point instrument you can to mark/scribe the center point
3) Use a punch or similar item to enlarge that location to the point your brad point drill bit or whatever you are drilling with doesn't wander. Sometimes this means using a progressively larger punch to keep that mark point exactly in the middle.
4) Use a drill press whenever possible. If not possible, take extreme precaution to make sure you are drilling vertically at all times as a bit that bites into the surrounding material on an angle will often times walk away from your center point.
5) When you find a mistake, stop and fix it now even if that means starting over. Mistakes grow. What is wrong at the beginning of a line by 1/128" will often be off 3" (or insert multiple feet..damhikt) the farther away from the beginning you are. Often trying to repair an "oops" results in an increased frustration level, loss of time and further complications later. Not that they can't be fixed but sometimes it's better to punt.
6) Walk away before fixing or starting over. Figure out why it's wrong and how you can prevent the mistake from happening again. Mistakes happen and some are preventable. Not learning from them is inexcusable.

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Bobby Masten

Great advice thanks Bobby

Bit annoyed with myself for not spending much more time on accuracy

Once again saw the finish line and started racing towards it (promised myself i wouldnt this time) haha

Might be a typo at B-a, but lots of people use alternate tunings..
We know what you meant.
I'd probably go for another one if it's not going to break the bank.
This one could be put to other uses, even if it's nailing it to the wall in front of you at the bench to remind you to check measurements yourself at least 3 times and never trust anyone else's.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Bobby's points above ore good. #6 is wonderful advise that we sometimes forget!

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Ha yes sorry was a typo doh

I would work with what you have there.
Good ideas given here.
If you filed the holes like Dennis said,
correct the string slots prior to the saddle,
then carefully notch the saddle accurately,
you could be good.
Next time, if you draw square layout lines for the holes,
from the square side of the bridge,
your holes would be more even .
Since you have an arc hole layout,
less error.
Personally, I prefer a ruler to a caliper here.
Tape it on the bridge,
and keep adding the space to the previous space, until you're done with the 6 hole layouts.
Then definitely counter punch!

Good repair suggestions do some practice fixes if you like --- but to me this is an obvious do over.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Bridges aren't that hard to make and the material cost is usually minimal. I recommend making another one.

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Steve Smith
"Music is what feelings sound like"

I've got five or six kicking around with similar problems, that's from making four guitars. I call it practice.

I am not sure how you are doing your layout but I would suggest one of the simple free drawing programs that print to scale (there are many available). Make an accurate drawing, print, paste it on the blank -- drill, cut -- Bingo! And as indicated above its a much better layout practice to plot points in series dimensions rather than moving to add one to the other. $.02

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Ken Cierp

http://www.kennethmichaelguitars.com/

I think the most relevant issue to accuracy here is hand vs. drill press. Even the cheesiest bench-top drill press w/ a brad point will dramatically improve things. A few blown Ebony blanks and you'll have paid for one.

Found this on Ken Cierp's site. For those without a drill press he's got a couple unique methods to make sure you drill straight holes that are worth checking out.

https://www.youtube.com/watch?v=r7yLMN- ... r_embedded

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Bobby Masten

Thanks Bobby

I liked Dennis K's suggestion. Moving the G to b distance less than 1/2 a mm (.4mm) would bring all the thinner strings to 10.7 mm apart. An extra .1 mm between the thicker strings I think is a good thing and probably wouldn't be noticed by anyone- the actual difference will be less because the strings thickness takes up some space.

I like the sound of that. Any names you want to put out there?

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Joe Beaver
Maker of Sawdust

Just Google free CAD software -- they all work pretty much the same. I think the majors like Autocad and Turbo etc. have free full function student versions. You can buy outdated versions of Turbocad from Amazon for a few dollars. I have not used it but many like Google "Sketch up" What ever you choose make sure it prints to scale.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Thanks Ken, I'll give it a try.

Cablepuller,
I would plug the holes and have another go at it. If you are pretty sure the remainder of the existing holes won't show then you can plug with any wood.
I would lay out the 1st & 6st string holes making sure they are equal distance from the centerline, marking the spots with a punch. Then use something like the StewMac String Spacing Ruler and mark the others. That will keep your spacing nice and even.

One other thing, any little error will tend to show once the pins are in. You do want then even spaced or as I like it, a slight increase in space per hole based on string diameter as the StewMac Ruler does.

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Joe Beaver
Maker of Sawdust