Boy, my current build is giving me no end of grief. I am making a new bridge after the first one split under string tension along the lamination while stringing up. I noticed however that one of the 18 holes on the new bridge hadn't gone all the way through the tie block. Using a eggbeater style had drill I have broken the 1.5mm drill bit in the hole and in the attempt to remove it with plyers, the end has broken off flush with the back edge of the bridge.
Any ideas about how to remove the bit now without making a mess of the bridge would be welcome:
Apologies for the bad photo - but you can just make out the drill bit
Broken drill bit in tie block
- lamanoditrento
- Blackwood
- Posts: 585
- Joined: Thu May 05, 2016 9:50 am
Re: Broken drill bit in tie block
The only idea Ive got - get a bit of stiff fencing wire and bend over a few mm of the end. Poke the bent over end into the saddle/tie block valley and push the drill bit out the back of the tie block enough to grasp it with the pliers.
You mentioned the previous bridge failing under tension. Id be interested to see pics of the bridge.
You mentioned the previous bridge failing under tension. Id be interested to see pics of the bridge.
Martin
- Steve.Toscano
- Blackwood
- Posts: 489
- Joined: Thu Feb 07, 2013 11:43 pm
- Location: Port Stephens NSW
Re: Broken drill bit in tie block
Does the hole go through to the otherside? If so as Martin mentioned push it through with some wire or a nail from the saddle side.
Otherwise maybe you could drill a temporary hole from the saddle side at an angle over the top of the saddle slot to meet up with the end of your drill bit then push it through.
Afterwards carefully filling the new temporary hole.
OR
You could route a bevel across the back of the tie block, careful not to hit your drill bit with the router/dremel but go very close to it. This should allow you to get needle nose pliers in to remove the drill bit - ensure to pull straight and twist obviously. After removal tidy up with the router/dremel.
See below what i mean with the bevel. I do this on all mine now anyway, looks good, with the added bonus of weight removal. Sorry i dont have a better photo showing it at the moment. I do this with a ball ended dremel bit upside down in a make shift table and a fence.
Otherwise maybe you could drill a temporary hole from the saddle side at an angle over the top of the saddle slot to meet up with the end of your drill bit then push it through.
Afterwards carefully filling the new temporary hole.
OR
You could route a bevel across the back of the tie block, careful not to hit your drill bit with the router/dremel but go very close to it. This should allow you to get needle nose pliers in to remove the drill bit - ensure to pull straight and twist obviously. After removal tidy up with the router/dremel.
See below what i mean with the bevel. I do this on all mine now anyway, looks good, with the added bonus of weight removal. Sorry i dont have a better photo showing it at the moment. I do this with a ball ended dremel bit upside down in a make shift table and a fence.
- Trevor Gore
- Blackwood
- Posts: 1609
- Joined: Mon Jun 20, 2011 8:11 pm
Re: Broken drill bit in tie block
IF you managed to drill right through before it snapped AND you have a drill press...
...set up the bridge in a drill vise so that any hole aligns co-axially with the chuck. Put the busted part of the drill in the chuck, upside down. Using the drill stump as a drift, press the broken piece of drill through its hole from the butt side. (Don't switch the drill on!) When it meets the saddle ramp, snap off the piece you can see with a pair of needle nose pliers. (Twist sideways rather than up). One repeat and you should have it all pushed through and a clear hole.
If you didn't drill right through, you should be so close as makes little difference. Try the same trick and hope you don't get too much splintering as you break through.
Good luck!
...set up the bridge in a drill vise so that any hole aligns co-axially with the chuck. Put the busted part of the drill in the chuck, upside down. Using the drill stump as a drift, press the broken piece of drill through its hole from the butt side. (Don't switch the drill on!) When it meets the saddle ramp, snap off the piece you can see with a pair of needle nose pliers. (Twist sideways rather than up). One repeat and you should have it all pushed through and a clear hole.
If you didn't drill right through, you should be so close as makes little difference. Try the same trick and hope you don't get too much splintering as you break through.
Good luck!
Fine classical and steel string guitars
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.
- lamanoditrento
- Blackwood
- Posts: 585
- Joined: Thu May 05, 2016 9:50 am
Re: Broken drill bit in tie block
Thanks everyone, I will give these a go. It is funny how when you're a bit downbeat your problem solving skills can go out the window. I think having to remove the 1st bridge, mucking up the finish a bit removing it and then struggling with broken bit knocked my resilience. I really appreciate replies and the collective wisdom here
Here ya go - the original was only a 6-hole and made pretty much per Trevor's method. Lamination was rosewood/cf/tassy oak/cf/rosewood with epoxy
Trent
Re: Broken drill bit in tie block
Ouch, so disheartening for sure.
Many times, I walk away and come back to it the next day, as our mental aspect becomes very fogged when frustrated.
Steve
Many times, I walk away and come back to it the next day, as our mental aspect becomes very fogged when frustrated.
Steve
- Mark McLean
- Blackwood
- Posts: 1086
- Joined: Thu Apr 10, 2008 2:03 pm
- Location: Sydney
Re: Broken drill bit in tie block
I do love the look of that bridge. And 18-hole is a great design for tying the strings quickly and neatly, and so much neater than tying them around the tie-block. Your triplets of holes are a lot neater than my last effort at that. I am sure you will get there in the end.
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