Cutting nut slots on Dobro so that top of strings are level with each other?

[Ryan Matzen]

Hi everyone,

What’s the best way to cut the nut slots on a lap steel guitar so that the tops of the strings are all level with each other? Thus, enabling the slide be in good contact of all strings at the same time?

Is there some kind of tip/trick on how to easily do this?

I started working by laying the bar across all of the strings near the nut. Then, I play all of the strings at once. I figure that the strings that ring clear are obviously higher. And, the lower strings buzz slightly. So, I will slowly file down the slot for each high string. Unfortunately, it seems that no matter how slow I have been going at this, I can’t seem to get all of the strings to ring clear all at the same time when the bar is just sitting on the strings near the nut. They will however ring clear with a little weight from my hand. I admit that I am a bit of a perfectionist. But, is there a time when the string heights are just “close enough”? I am beginning feel like my Dunlop bullet bar isn’t totally flat!

Thanks in advance!

All the best,

Ryan

[Ryan Matzen]

I just spent another half hour trying to get the tops of the strings as level with each other as possible. Using the method that I described in my original post, I believe I have now gotten as close I can. I am still wondering if there might be a better way of doing this? I can’t think of one. So, I was wondering if others approach this job any differently?

Ryan

[Mike Kolb]

My brother's a dobro player and I've cut a lot of nuts for his different instruments over the years.  I've asked him that very same question about getting the string height right at the nut so that the bar "sees" a level field.  His response was pretty-much along the lines of "within reason, it doesn't matter".  

Since the bar rarely (if ever) comes-into play right at the nut, just get it as close as you can. Any small differences in height will minimize themselves the further away you get from the nut, so I think it's splitting hairs to try to get any more precise than necessary. 

As always, though... your mileage may vary :)

[Ryan Matzen]

Thanks for the input. It’s good to know that it doesn’t have to be “perfect”. After a lot of tedious filing and checking, I am now able to get all of the strings to ring clear when just setting the bar on the strings without any hand weight,

[Chris Vallillo]

No "trick" I know of, simply hard work and lots of measurements of the string slot, string thickness and string height.  I play a lot of bottleneck slide on vintage guitars (main slide ax is a '36 Dorbro spider cone) and I've had a hard time getting lutiher's to get the concept that the string need to be level at the top, not the bottom as on a standard guitar.  This really came into play when I had a custom built 9 string guitar made.  A 6 string used for slide is a lot more forgiving than a 9 or 12 string for slide. The guitar was patterned after the relatively obscure Lyon and Healy 1201 nine string (made only in 1920 and 21 of flat sawn birch, ladder braced with a headstock reminiscent of the Stromberg-Voisinet headstocks of the era).  I had restored and X braced an original 1201 (in terrible condition!) and an excellent luthier saw my modified 1201 and offered to rebuild it to Larson specs. It ended up being a spectacular instrument, but the first three strings are doubled like a 12 string which makes the strings being leveled on top critical in order to "ring" both strings when playing slide; particularly the thinner of the 2 in any pair.  I ultimately had to take the guitar to a set up specialist to get the action set the way I need it.  Once the tops were leveled to one another, everything was fine.

[Ryan Matzen]

I totally agree with having a hard time “getting lutiher's to get the concept that the strings need to be level at the top”. That is why, that after two visits to two different guitar shops, that I am just doing it myself. I have found it best to get the two outer strings at the height that you want them. Then, add and work each of the remaining strings one at a time. I still have a 1929 Tricone at a shop. I am dreading picking it up as I am worried that it won’t be right. I already had that at a very reputable shop. And, they completely botched the nut. I can’t imagine doing a 12 string! Actually, I can!

[Chris Vallillo]

Yes, my '36 went to a number of well respected luthiers before I finally found a great one.  Best I've ever worked with is Rick Cremer (Cremer Guitar Works) in Aurora, IL.  He's always busy as hell but absolutely a magician on set up.  I applaud you for going at it yourself and it sounds like you're on the right path.  From here on out, it will all be about precision.  I bought a Stu Mac nut cutting tool to do nuts more accurately (StewMac Safe Slot Nut Guard, https://www.stewmac.com/luthier-tools-and-supplies/tools-by-job/too...) I have not mastered it by any means, but it did teach me a lot about figuring out exact set ups.  It involved copying the fingerboard radius (if it has one) to the nut blank, measuring the fret height and adding in the amount string height you want.  You get precise measurements by filing the nut slot down to a feeler gauge placed next to nut that is the exact total of all your measurements.  As I said, I have yet to master this tool, but it does make the BOTTOMS of the string consistent if you work it correctly.  

[Ryan Matzen]

I used to do something similar with feeler gauges and a elastic hair band.

[Chris Vallillo]

Actually, re-reading this I see you'd still need to adjust the final cut in the saddle based on the string thickness to perfectly level the tops of the strings.

[Ryan Matzen]

Plus, the nut height on a lap steel/dobro is quite high. So, that tool/method wouldn’t realistically work anyway.

[Chris Vallillo]

I could see your point on a square neck Dobro. I actually play bottleneck slide on a round neck and set my nut approx 1/16th above standard set up so I can finger behind the slide for additional passing notes. 

[Ryan Matzen]

For me, (round neck) guitar nuts are pretty straightforward to make. The nuts that I am inquiring about are on lap sleel guitars that have square necks. I was just wondering How others go about making these. And, if the strings tops have to be perfectly level. Or, a if a little amount of variation in string top “levelness” is acceptable on these types of guitars.

[Taffy Evans]

Hi, would this work for you?

In a blank nut, file the string slots so that all the string tops are level with the top of the nut. Using a small steel ruler or feeler gauge you could determine this by dragging it across the nut surface, or site under the ruler at the string slots.

Now, strings are all same level on top but too deep in string grooves, and the first fret action is too high…so

Set string action over the first fret by removing material from the bottom of the nut…then

Remove material from the top of the nut to get desired groove depth for each string.

I have not tried this I must say, let me know if I have overlooked something.

Good luck Taff