2mm diameter drill bit bends?

UKworkshop.co.uk

Help Support UKworkshop.co.uk:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Yes they are decorative. So on a finished fretboard they only need to be 5mm deep.

But I was going to build some unfinished fretboards with the fret slots cut and holes for side dots drilled. They would be trimmed to size by the customer.

The pre trimmed fretboard size would be 65mm in width but since the nut end is narrower the dot marker holes would need to be deeper due to 10mm that would be trimmed off the sides near the nut due to the taper of the guitar neck
thanks
 
As a retired guitar maker I can recommend these Proxxon 6 Piece HSS Twist Drill Set 476782 Drilling side dots is what I bought them for and they work fine. Just make sure the fb's /neck is fixed down on the drill press and you don't have a lot of run out on your drill. Clear the drill regularily (peck drilling) whilst drilling. I would also make a jig (someone with a cnc machine can help here ) to line the dots up. A 6mm thick piece of clear polycarbonate will work to start the drills. I assume your making bass guitar fingerboards with those dimensions. I'm not sure if I would bother with all of this, as if the end user has the capability to glue the fb onto the neck, he should be able to drill the side dots holes. Guitar making requires some skill. Some customers might also want dots drilled half fingerboard half neck like Fender used to do. Try the proxxon drills.
Cheers
Andrew
 
I wonder if you might be able to make a starter hole by driving a suitably sized panel pin into the wood a couple of mm deep, would give you a nice round hole to start the drill off?
 
Thanks, I bought one of these just to do the one job or any other small pieces work

Bosch PBD 40 pillar drill

I have a Axminster trade pillar drill but it seemed to large and brutal for the job. Plus I use it for metalwork so it's all a bit oily and greasy.

I bought the Bosch pillar drill locally second hand but unused so cost me just short of £200

Im impressed with it for small work. Its very quiet has electronic
speed control on the front. But the best thing is an electronic read out of the depth stop on the front screen. Zero it and it reads out the depth in 0.1 of a ,mm.
It seems ideal for small bits but then people use them with 42mm Forestners bits online
Have you tested the amount of run-out on your PBD-40 ?
I only ask because the 'out-of the box' run-out is awful (and led me to change the chuck spindle needle bearing on mine for roller bearings which massively improved things).
There's several YouTube clips out there explaining how to do it ...
 
Not strictly true. If you have deep enough pockets then you can get on these or variants thereof... 'optical punch' will get you there

View attachment 168962

Gosh, I thought - that is expensive - I will link to the set I got from Axminster (years ago) that must be cheaper ….

https://www.axminstertools.com/axminster-optical-centre-punch-100244
Hmm - I really don’t recall what I paid for mine, but it is an absolutely excellent tool (only let down by the annoyingly oversized foam-lined case it comes in. It is difficult to explain the clarity you get in locating the crosshairs (or small circle) over the mark to be centre punched.

Cheers
 
Anyone mentioned masking tape, I use this a lot and it is easy to see your mark, I use either a prick punch or std scribber to make the indent by just pushing it into the timber, no hammer required. With something like Sapelle you do need to give it a gentle tap and the tape is even more important for seeing the mark.
 
Anyone mentioned masking tape, I use this a lot and it is easy to see your mark, I use either a prick punch or std scribber to make the indent by just pushing it into the timber, no hammer required. With something like Sapelle you do need to give it a gentle tap and the tape is even more important for seeing the mark.
And really surprising how just a bit of masking tape can help stop the drill wandering.
 
Drilling side dots in wood should not be problematic, unless your drill bit is dull, so get a sharp drill bit, and really, no pressure should be needed, de drill cuts because it's cutting geometry (sharpness). If it doesn't, leaning on it will not help, it'll just snap. And indeed, marking with an awl, but since it is a fingerboard, so quite a narrow strip of wood, you need to take a little bit of care, to not split of an edge of the board.
Good to see there are other guitar builders here!
Building a similar sort of thing as a Mayones Cali4 bass myself, so a sort of travel instrument, but then a 5 string, my own bodyshape, and a slightly longer scale length (530mm).
Screenshot 2023-11-01 152247.png
 
I use a solid carbide stub-type bit for exactly this. You only need to go in a few mm anyway, 3-4 is plenty, but my bit has about 15-20mm flute on it.
Side dots have been punched from celluloid sheet back in the day, so very shallow, there's no real advantage to going more than a few mil.

I mark my line and go straight in, don't need tape or dot punch etc, the carbide doesn't need it. I have longer 'jobber' ones, they're less trusty on the non-wobbly score, but the stub bit needs no help.
 
was thinking about cutting the shank down by 20mm so it's still fully in the chuck but only 20mm stuck out

More accurate the other way around.
why is it more accurate to cut down the tip than the shaft? I would have assumed that a factory machined tip would be be more accurate than a home sharpened tip, so better to reduce the shaft where accuracy is not important.

I can only think that reducing the shaft would leave the chuck gripping onto the grooves / auger rather than a smooth shaft which could introduce error, am I on the right grounds??

I wonder whether a collar (with an opening / gap down one side to allow for tightening) down the length of the bit would give the extra bit of support needed
 
Using collets instead of a chuck would also help, I have a small proxxon pillar drill TBM220, and that has very little runout, especially when using collets.
 
So with drill run outs is it normally the chuck at fault? I've seen videos where they change the chuck to a £90 one and it improves it.
I haven't measured for run out but I tried the 2mm drill bit shank in the hole and it was fine
 
No, it is everything in that mechanism, the bearings, the sliding mechanism, the chuck, the drill shaft. But, for a manufacturer, a chuck might be a "buy-item", and the bean counters might over time choose one which is 5 cents cheaper, and those machines will benefit from a better chuck, in other cases, where the bean counters are being put in their closet under the stairs, and everything about a machine is high quality, not so much.
 
why is it more accurate to cut down the tip than the shaft? I would have assumed that a factory machined tip would be be more accurate than a home sharpened tip, so better to reduce the shaft where accuracy is not important.
Because the fluted part is much more flexible than the shaft, and drill bit flex seems to be your main issue. For those size holes I concur with others that suggest using a pecking technique with quality stub drills, or solid carbide. Be careful with carbide though - if there's any radial movement in the rest of your setup, carbide bits snap very easily.
 
Back
Top