Aluminum Radius-sanding Beam

  • 46 Reviews
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Extended length for fast, precise shaping. Create a constant radius on an unfretted fingerboard, or level installed frets with this unique tool for the professional guitar shop.

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7-1/4" radius

Item # 5640
In stock, ready to ship!



9-1/2" radius

Item # 5641
In stock, ready to ship!



10" radius

Item # 5642
In stock, ready to ship!



12" radius

Item # 5643
In stock, ready to ship!



14" radius

Item # 5644
In stock, ready to ship!



16" radius

Item # 5645
In stock, ready to ship!



20" radius

Item # 5646
In stock, ready to ship!


Total: $0.00
Quantity: 20


Radius-sanding Beam

Erick Coleman using a Radius Beam on a fret job for leveling the board, then the frets.

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Extended length for fast, precise shaping. Create a constant radius on an unfretted fingerboard, or level installed frets with this unique tool for the professional guitar shop.

The 18" long extruded aluminum block is comfortable to hold, and its stiffness and precisely machined radius assure accuracy that's not possible with a wooden block of the same length. We designed this tool for a lifetime of use in the busy shop.

Lifetime durability • Extended length
Fast, accurate fret leveling and fingerboard shaping

Dimensions: 18" long x 2-3/4" wide (457.2mm x 69.85mm)
Seven different radii are available, for popular fretboard shapes.

A great clamping caul for glue-in fret jobs!
"I use aluminum fretboard sanding blocks to hold and clamp the frets in place while the glue dries...A scrap of Neoprene on the bottom of the caul protects the frets from the texture of the machined surface, and serves as a cushion that conforms to the radius a little better, conforming to any slight variations in the fretboard."
Excerpt from Erick Coleman's book Fret Work Step-By-Step

Cut and stick!
3M Stikit Gold Paper Self-adhesive Abrasives are the right width for our leveling and radius sanding tools. Attach 80 through 220-grits for radiusing and leveling the fingerboard, and 220 through 400-grits for leveling the frets.

Works on stainless frets, too!
All of our tools are suitable for use on stainless-steel fretwire, with the exception of our Fret Tang Nippers and Fret Cutters. Modern stainless-steel fretwire is known to be harder than the traditional nickel-silver blends, but our own shop experience indicates the wire does not cause premature wear of files or sandpapers.

Product Instructions

Radius Block Basics

An explanation of the different uses of a radiused sanding block.

Ratings & Reviews

Aluminum Radius-sanding Beam

  • Based on 46 Reviews
Displaying 3 of 5 1 2 3 4 5
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16inch radius sanding beam

By Quentin Howarth from Cumbria, England.
(Customer's Reviews) Saturday, April 28, 2012

This is a quality piece of kit, and has a satisfyingly heavy/solid feel in your hand. The radiused wooden blocks give pretty decent results, but these are a marked improvement. As a previous reviewer quite rightly pointed out, these 18 inch beams are best used in a simple jig, to keep it absolutely parallel to the piece you are sanding. Done this way the results are faultless.

Amazing Tool

By cknob from Media, PA
(Customer's Reviews) Tuesday, April 10, 2012

Makes fretting and leveling a joy. I glue in the fretboard and then progress from 80 grit through 320 grit until I get the perfect radius and thickness. I drill the shallow holes for the pearl dots and glue them in. I level them with the radius block with 220 and 320 grits. I press in SM fret wire with a SM Jaws 2 fret pressing system. I sight down the fretboard and make any adjustments needed with a few hammer taps. I level with the 18ö block with 320 grit until the frets are perfectly level and if IÆve done my job with a good wood sanding and good pressing, the adjustment is minimal. I recrown where needed with a SM diamond crowning fileà400-1000 grit paper and steel wool until the frets and fretboard are buttery smooth and thatÆs it. About 2 hours start to finish and much less opportunity for screw ups. Great solutions from this company.

A must have

By Martin (Beaud) from Gatineau,quebec,canada
(Customer's Reviews) Monday, March 19, 2012

Really Nice useful tool... Well made And tough. Thank you stew!!!


By JLondon from Owensboro, KY
(Customer's Reviews) Thursday, March 01, 2012

From the looks of the other reviews there's not really much else to be said. Get one (I mean three). Definitely one of the top ten best tools in the Stewmac catalog or anywhere else for that matter. I used one for the first time to radius a hand made one-pc. maple electric guitar neck and level frets. Simply, and perfectly marvelous. Due to the tool's length you don't have to worry, when leveling frets, about sanding too much or too hard in one spot. Just move it back and forth and let the tools own weight do the work. I agree that, as mentioned in another review, that a temporary jig/straightedge can be beneficial to keep tool from moving unevenly side to side - but not totally necessary if your the least bit careful.

Aluminum Radius Sanding Beam

By Mike B from Bradenton, FL
(Customer's Reviews) Thursday, February 02, 2012

Finally bit the bullet and bought the 12 inch radius beam. Although pricey, I will say that it is an outstanding tool and extremely well made. Another example to show that even if expensive, it will be inexpensive in the long run and makes my guitar making easier and more precise.

Really OK!

By hans guitars&repairs from T++bingen, Germany
(Customer's Reviews) Thursday, January 05, 2012

The sanding beam is a heavy tool thats doing his job. Unfortunately there was a little transport damage. Nothing big, but I think the packing is a little unstable for overseas-shipping for such a delicate instrument.

I've bought some tools now from Stewmac. The overall quality is good but not ecxellent. You get a better quality when you buy in a german DIY store. Honestly, what really wins are the great tool ideas, but the quality aspect is holding me back to buy some other stuff, that I don't need right know.

Keep it straight

By Francis Voignier from Arcata, CA
(Customer's Reviews) Wednesday, January 04, 2012

Indispensable tool for fingerboard and frets leveling for no-buzz low string action. Forget the radius wood blocks!

exellent tool but...

By R.G custom guitars from Israel
(Customer's Reviews) Sunday, November 27, 2011

excellent tool but when working on a fingerboard radius ,you must make a jig ,that wont let you move from right to left while sanding.THIS IS A MUST!!!!!

Good Tool

By Eric from Milford,NH
(Customer's Reviews) Friday, November 04, 2011

Great tool. Accurate work is much easier.

Aluminium Radius Sanding Beam

By Pat Green from UK
(Customer's Reviews) Tuesday, October 04, 2011

I purchased the beam some years ago and have used it constantly ever since. It produces a very accurate camber for the fingerboad and can also be used to level the frets. I also use the flat side of the beam for sanding flat tops on solid guitars and for fret leveling. I find the more accurate the camber is made on the fingerboard the easier it is to get the frets right with a minimum of leveling/re crowning and this beam is excellent for this purpose. To get the camber accurate and at right angles to the axis of the fingerboard I put the beam between 2 rails and mark out the centre line. The blank then is held centrally between the rails and the beam runs between them giving an accurate camber. Pressing the frets solidly against the camber then produces a very even set of frets requiring minimal leveling.

Displaying 3 of 5
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