Safe Slot Nut Guard and Feeler Gauge Set

  • 14 Reviews
  • Write a review

Stop your file before the slot's too deep and your nut is ruined! This Safe Slot Nut Guard includes an 11-piece feeler gauge set.

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Safe Slot Nut Guard and Feeler Gauge Set

Item # 1823
In stock, ready to ship!


Total: $0.00
Quantity: 20


Safe Slot Guitar Nut Guard

Stop your string slot file before it cuts too deep and the nut is ruined! StewMac's Dan Erlewine and Don MacRostie, the inventor of the tool, show how it works.

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Stop your file before the slot's too deep and your nut is ruined! This Safe Slot Nut Guard includes an 11-piece feeler gauge set.

Cutting string slots is delicate: if you cut one slot a little too low, you've blown the nut and have to start over. StewMac's own Don MacRostie devised the Safe Slot™ to make accurate nut slotting fast and fumble-free. He shows us how it's done in this video!

A trick the pros use:
Stack feeler gauges against the nut to set your slot depth. When the slotting saw touches the feeler gauges, you've hit your depth. The Safe Slot Nut Guard holds the feeler gauges tightly against the nut, and curved to the radius of your fingerboard. This leaves both your hands free to file. And you'll be able to work faster without worrying about cutting too deep.

  • Holds multiple feeler gauges
  • Pulls gauges tight to match fretboard radius
  • Locks in place against the nut. No slipping!

The pivoting caul adapts to most neck shapes, and the felt padding is guitar finish friendly. Use the clamp for any fingerboard up to 2-1/16" wide.

Set of 11 steel feeler gauges
Dimensions: 6" x 1/2"
.016" .022" .028" .034"
.018" .024" .030" .040"
.020" .026" .032"

Ratings & Reviews

Safe Slot Nut Guard and Feeler Gauge Set

  • Based on 14 Reviews
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Safe Slot Nut Guard

By Popsdaddy from San Diego, CA
(Customer's Reviews) Thursday, April 24, 2014

Great idea and good for a safe start. Fret height is the true definer here. If thats not right (fret height definition too low) you got problems for the beginner. You would be wise in purchasing gauged nut saws to save file wear and breakage. Otherwise if you top the nut height right you won't have to go so deep with files. Well made as everything this company makes is. I'm still deciding on it. Don't get me wrong, Stew-mac is a guitar tech's heaven, I love tools and especially ones that speed-up work and raise quality. Thanks for the forum!

Amazingly simple

By Tim G. from Sarasota , Fl
(Customer's Reviews) Sunday, April 06, 2014

This tool makes the job so much easier.It takes the guess work out of how deep the slots should be. I highly recommend this tool! It's a must have!

Easy Slot

By JMW from Biggleswade, UK
(Customer's Reviews) Saturday, March 29, 2014

A great little tool. Much easier than trying to hold the feelers by hand. With the correct amount of tension applied the feelers conform exactly to the fret-board radius to give perfect depth slots.

Its a cool tool but...

By Guilherme Brederode from Lisboa, Portugal
(Customer's Reviews) Tuesday, March 25, 2014

Hi guys! I received the Safe Slot Nut Guard last week here in Portugal and already used it. Its a cool tool...shurely a helper, but the old japanese 70's acoustic I was fixing and making a new nut, had a the headstock in a deep angle, so the Nut Guard had to stay a little far from the nut. It helped me making me the new nut but I had to be carefull not to damage the fretboard with the file. Nevertheless im glad I bought it

Doesn't work with necks having a thumb crest

By Doesn't work on some banjos from California
(Customer's Reviews) Wednesday, March 12, 2014

Many banjos have a knob or crest on the back side of the neck opposite the nut as a place to put one's thumb. The yoke of the safe slot does not work with such a design.

Simple, Excellent

By Tomm Stanley from Christchurch, New Zealand
(Customer's Reviews) Wednesday, February 19, 2014

A very clever little tool, well worth the price.

A helpful tool!

By Rockin' Mike Burton from Canada
(Customer's Reviews) Thursday, February 13, 2014

This tool was a real help in getting the initial radius and slot depths right, but I am not sure how effective it can be if you are trying to get some super-low nut action. I still proceeded without the guard when getting down to the final depth (0.012 - 0.010") is very low where every stroke counts. Maybe with a bit more experience and experimenting with this tool, it could be used to cut the slots that low and save a lot of time...we shall see.

Saved my nutz

By David Kaman from Ohio
(Customer's Reviews) Tuesday, February 11, 2014

This device has saved me from a lifetime of "Damn, I cut that slot too low" I am a perfectionist. Your Safe Slot Nut Guard has made me a little more perfect. Thanks a million, Dave "I'm a little surprised I didn't think of it first".

Never ruin another nut

By axe fixr from Richardson (Dallas) Texas
(Customer's Reviews) Sunday, February 09, 2014

The Safe Slot Nut Guard is a wonderful, easy-to-use tool for cutting the nut to the exact string height. Instructions walk you thru the procedure with ease and by the time you get to the 3rd groove, you'll be a pro. Especially with brass nuts, where mistakes get costly.

Safe Slot

By Roger Sadowsky from NY, NY
(Customer's Reviews) Monday, February 03, 2014

We were so impressed with the new Safe Slot system I ordered 5 of them for every builder in my workshop!

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