View Full Version : Nut Slotting

07-10-2016, 06:43 AM
I'm getting some buzz on my A string, which I have narrowed down to a sloppy nut slot. I have been using those welder tip cleaning files, and find it difficult to cut a clean slot.

What are other people using? I see the pippin file from lmii, and Stewmac has specifically gauged files, which are kind of pricy. I'm a hobbiest only, looking for suggestions.



Bob Orr
07-10-2016, 07:08 AM
I found a set of diamond needle files quite cheap and in the set is a long tapered needle file which is what I use. It has a long thin taper so you just stop at the part of the taper that corresponds to your string gauge. I mark the positions in pencil and start them off with a razor saw which helps to stop the needle file wandering.

Cheers, Bob

07-10-2016, 02:34 PM
I use a cut off from half of an 18" fine-toothed hacksaw blade to get the nut slot down and cut at the correct angle and approximate height for the intonation to be as close as possible on the first 5 frets...

THEN I use whichever gauged welding tip cleaner matches the string diameter for the slot to simply and ONLY 'smooth' and ROUND the bottom of the slot.

I find that the welding tip cleaners cut too slow on anything other than cheap plastic, and due to being as flexible as a noodle, have too much waggle during the filing stroke to cut a perfectly parallel slot. Steel or not, with enough pressure to cut as a FILE, they sure bend an awful lot.

Also, if your hacksaw blade is hard to pull, lay it flat on the bench, on some stone or even wood block, and give it a couple of good passes of hard smacks with a hammer along the teeth, (perpendicular to the side of the blade)) up and down the length, both sides of the blade. This will flatten the teeth so they cut on the EDGE of the blade and NOT on the SIDES, which will leave a RAGGED side wall of your nut slots. Saw this tip in some luthery videos on YT a while back, but forgot who the person was.

Hope this helps....

07-12-2016, 01:05 PM
Thanks all, for the input. I guess i will try the little gent's saw I have or a hacksaw blade to get the slot close, and then use the tip cleaner as the final step. I see how that could help with slot control. And then, when that doesn't work, I'll probably buy the files from SMD. I do wonder if that LMI pippin file would work, though...


07-12-2016, 01:16 PM
I am actually quite surprised that you did not get any replies from more of our resident builders here on UU.

I guess they are all busy in the shop, well, building, and it's just hacks like me that have time to mess around online. LOL

Seems like you'd get a concise and perfect answer from one with expert-level experience, which I fully admit that I do not have.

Good luck with the project!

07-12-2016, 02:33 PM
Over on mandolin cafe there's a great Set-up E-Book by Rob Meldrum. If you email Rob he'll happily email you back his little book for free. Pretty much all the advice he offers for a mandolin transfers directly to the ukulele. He has several helpful tips for filing a nut or a bridge. HIS interesting scheme for a person who doesn't want to shell out $15 or so for a fret file is to create one from a feeler gauge.

I think, there's nothing quite like a dedicated file. If you cut scores of nuts over the years, the needle file approach is fairly easy but without a lot of experience it's a bit of a riddle. The dedicated file will almost give you guaranteed result. No matter which way you go, it makes sense to practice on one of your ruined nuts until you're satisfied with the results. That might help cutting down on ruining your investment in material, layout time, and feeling good about that instrument.

07-12-2016, 03:56 PM
Luthiers who do this for a living have the all the nut files they need. You pony up the money in the beginning and you don't have to think about again. I've been using my files for over 20 years and they have more then paid for themselves many times over. If I were a hobby builder, I would use a sharp 3 corner file for all the strings.

Michael N.
07-12-2016, 09:37 PM
The LMI Pippin file is OK, just a matter of practice. I mainly use just one fine round needle file though and have done for decades. Just use a hard wood like ebony and practice cutting string slots. Eventually you'll get the feel for each string dimension.

Inksplosive AL
07-13-2016, 01:20 PM
Go to your local harbor freight and take a gander at their cheap file sets. Ive found two one steel and one diamond set with knife files which are not perfect. This is what made them perfect for the touch ups I need on my personally owned ukulele nuts. Instead of being a sharp edge they are a bit rounded in areas, those are the areas I use. They are at least made for removing material not like welding tip cleaners made to remove carbon buildup.

If I were building ukuleles I would buy the proper tools. Even though saying that as a pro tattoo artist I have tattoo machines that cost $500 and those that cost $50, I use the $50 machines the most. :)

~Good Luck~

07-14-2016, 09:12 AM
Thanks again for the input. Just ordered two from stew mac.