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Hi folks,

It’s that time of year for buying yourself something for the holidays. You’ve been good and working hard in your shop all year long. Why not consider this fret caul set from Birkonium?

Case in point - I’m fretting this dred today and as usual I’m pressing frets and with each fret using the fret rocker to check that I’m good. If not, give it another squeeze, check again, etc… until the fret rocker is happy.

I radius my fretboards to 16” and I typically press with the 14.75” radius caul from this set. It’s perfect because it’s a little over radiused and presses the ends down well.

I get to the 8th fret and it’s rocking. I try again with the press. Still rocking. I switch to the 12.75” caul, squeeze, no rocking. Awesome.

https://birkonium.com/shop/tools-misc/u ... -caul-set/




Treat yourself, you deserve it.

Brad


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I agree that the caul set is great, and I love mine, but that holder for the caul set you have is making me drool!

That’s a Hesh Tablesaw Tool Holder (tm) design!


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Looks like something i could make on new cnc. Ill add that to my list.

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Hutch

Get the heck off the couch and go build a guitar!!!!

Now that you mention it, I have a CNC and a set of ball end bits... I've always wanted a pressing set, but could never justify the cost. And the caul holder could be made effortlessly with a 3D printer The fret press bottom jaw blocks, too.

It's great to have a robot army, as long as they're the old fashioned type that don't try to think for themselves.

Yep would make a great gift and a couple of comments.

Brad no need to check every fret as you press them with the fret rocker because we are sill installing the frets there is an expectation that one will come back and do the final leveling and shaping of the fret plane.

A fret rocker... is not used by us at all, not even once in our fretting. It's not necessary and only is a tell tale of a small region of the fret plane where strings, natural straight edges see the entire fret plane at once.

We do use the fret rocker, I use it in fact if I suspect a high or loose fret while setting up a guitar but I can do the same investigation with the strings playing notes too.

When I press frets, Dave too and we use these sets every week (we have two of the original ones) we simply do all the deeds that make for a good seating of the frets and then rely on the final fret leveling after the frets are glued in place for the precision dial-in of the fret plane.

Some of the stuff we do is:

1) use a three corner file on the edges of each fret slot, just a couple swipes to break the hard edge so the the filet of material under the fret crown won't be blocked by a hard edge in the fret slot. This makes the fret sit more tightly against the board.

2) Use your tools to prep the slots further for the level of compression when you seat a fret. If it presses in hard it will eventually create back bow which you don't want. So clean the slots while trial fitting a fret until they go in nice and easy but not too easy.

3) I measure the board radius in maybe four places and set out the cauls that I want to use for those radiuses. If I need an 11" I might select a 10" so that I am sure to get the ends down good.

Anyway there are lots of things that will be done at the installation stage where the only real goal is well seated, not causing much compression and back bow frets. We will tune-up the precision of the level set later in the process.

Folks this set was developed by Andy Birko and David Collins my business partner in a collaboration. It's not just another pretty face it replaces two other sets that were on the market before it one from Andy and one from John Watkins before Andy.

What's different is the radiuses offered and I hope that anyone who has the set keeps this to yourselves it was painstakingly worked out by Dave for real world fretting work. I'm speaking of the most useful graduations between this radius and that radius. A lot of math was done with the help of a Western Michigan Math professor who is in Dave's family to determine the graduations based on a conical, compound radius model. And I'm also speaking of respecting our OLF vendors and their right to make a living from their hard work and IP (intellectual property).

We, Ann Arbor Guitars do not receive royalties from Andy's set but we have GREAT interest in protecting Andy's IP because he is a fellow member here and our dear friend. Please respect this.

I don't object to someone who has the caul set providing someone else with the radius graduations provided that there is a promise that it's for personal use and won't be provided to anyone else and/or that their intent is NOT commercial with the sale of the sets. Please don't ask me though I'm in the cone of silence on this....

My box is just like Brads and I threw it together one evening putting the entire box standing and laying through my thickness sander. I used medium CA on mine so it is a BLO (box like object) per Rick RIP Turner. Howards makes the box pop too.

I have the set too and it’s now indispensable.
Definitely gonna make a Hesh style box for mine.

Thanks, Hesh.

Is there a reason not to use the fret rocker or it’s just not needed in your normal workflow?

I started using this approach of testing on the way up with the fret rocker after watching Michael Bashkin’s fretting course.

He is using this approach because he wants to avoid having to level after installing the frets. The reason to avoid it is he’s doing the semi-hemi frets and they are already spit shined and ready to go at install time. So he doesn’t want to have to level and recrown / polish.

I’m not doing the semi-hemi’s at this time although I have in the past, but the method of ensuring the frets are seated with the rocker on the way up the neck has a nice side effect in that I don’t have to level and recrown.

This is of course on a new build where the board was meticulously prepped before starting to press in the frets.

After fretting I mark the tops with a sharpie, and take the long beam with 400 grit stick-it and place it spanning across frets 1-14. I move it just a little bit, if it kisses all the tops I’m good and move on to scotchbrite and polishing.

Any concerns with that approach? Seems to be working fine.

Thanks!
Brad


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I agree that Andy's fret caul set is a great tool. I've also got a holder like Brad's - just slice a thin edge of off a decent looking piece of longish scrap, use the table saw (or cutting thingamajig of choice) to make slots in the thicker piece for the cauls, then use CA to glue the thin piece back on. Glue on a base. Sand it all down and put some finish on it if you like. Easy Peasy.

I have a fret rocker and use it a lot on repairs - I like it for tapping frets to locate any loose ones. That's all I use if for anymore

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Steve Smith
"Music is what feelings sound like"

I was using the Stewmac fret press, but ran into problems. The frets weren’t matching the press exactly.

I just got the J Edwards Fractal Fret Press and it is impressive. Perfect fit everytime, no matter the radius.

https://www.jedwardsguitars.com/store/p/fractalfretpress?utm_medium=order-summary&utm_source=order-status&utm_content=name

I've just hammered them in so far, checking as I go with the rocker.
TAS edges me towards the Fractal press, but I did acquire a Jaws 2 type which I will try on the upcoming build.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Does the fractal work with the jaws? Fretting the board first is a major no no.


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Yes we don't use the fret rocker because it's a given that you will have to level the frets after installing them. I don't care how meticulously prepped the board is, we do that, board prep too but the installation process introduces variables especially with the Jaws tools that require human strength to drive the fret home.

I'll add that we do fret work for electric guitar players and some of them require action lower than a snake's belly in a wagon rut to quote the late, great Jed Clampett.

We assume that the frets may not be level to within 0.001" or less after installation so using the fret rocker to check anything is wasted effort and time. When we do level it is often the case that our frets are as level as anyone's after installation and even more level because we jump through hoops to level AND shape the board with relief with more on the bass side, less on the treble side and induced fall-away.

What you do Brad may work great for acoustic guitars where action is often higher and in some instances much higher than a jazz box electric or a shredder electric. But it is not good enough for precision fret work for many of our clients.

I would caution you and everyone else about combining methods. I'm sure that what Michael does has been worked out with great effort and is designed to provide great results. Our methods are as well but our methods include a degree of accuracy not necessary or intended for the usual higher action of acoustic guitars.

And here is yet another reason why semi-hemi fret ends are chasing a rainbow that out of over 20,000 repair clients we have never had a single request for semi-hemi fret ends. If what it takes to do semi-hemi fret ends that provide zero value to a player over well rounded fret ends requires one to sacrifice fret plane accuracy and pushes action up as a result that kind of trade off, playability for a fad that seems to have even passed already is to me a trade off I would never make.

Different strokes for different folks.

EDIT: Wanted to add that the leveling process is not just.... leveling frets. It's used with bluing (magic marker) to verify with a precision leveled beam that what you have crafted is indeed level. Or, in other words our fret rocker is a precision leveling beam.

EDIT II: I have an idea to put bluing tomorrow on my fret rocker and take it to the surface plate. It would be pretty interesting if the level set of the fret rocker is not all that.... If I do this I'll report back.

I stand corrected it does have a purpose and Steve's found it. I do use mine to verify a high fret but they usually just ask me for for some Doritos or Oreos.

So we built a couple of continuously variable fret cauls and still have them but didn't go forward with the idea because our's had some issues. Dave also knows Edwards and they have spoken about this and here's some things that we think would be issues for us if we tried to use his caul and were in fact issues that we ran into with ours which is very much like this Edwards caul.

1). It does not fit the Jaw's tool and we don't fret the board off the neck. If you do repair work you have to fret the guitar with the board on the neck, neck on the guitar. The Jaws II tool is the mainstay of our fretting operation and we love it.

2). The caul does not span the entire fret and there are issues with getting the ends down. So to drive the ends all the way home you have to move the caul and press sideways toward the two ends of a single fret. This means pressing a single fret perhaps three times. We only need to press our frets with the caul set we use one time.

3). In the repair world the remedy for a loose fret is a caul that is slightly tighter in radius than the fret so you can get the ends seated all the way. Then with caul in place holding both ends down we wick in CA and glue the fret. You can't do that with this caul or you have to do it twice since it does not span the entire fret.

4). A six string acoustic guitar is not the only thing people play. From classical with wider necks and no radius to 5 - 6 string bass guitars frets can be longer than this press and usually are. When pressing something and the press does not cover the entire span of the fret there is dimpling where to avoid that you have to move the work piece again to get the ends. Or in other words this caul does not provide uniform pressure the entire length of the fret in every spot at the same time. Our's from Andy does provide uniform pressure the entire span of the fret.

5). Dave found an imitation of this caul on Temu for $15 which is sad and a lot of other things since a lot of time went into this one but we can relate. Dave created an electronic test set shown in our videos on our web site and a year later someone in China was producing the same thing as a product.

6). Since you have to move the caul to the ends to seat the fret ends if you go too far and it's slightly over the end it will create a ramp sliding off the neck in the region of the fret toward the end. Our cauls over hang the fret but the radius of the caul does not change so it's no problem for us if we over hang the fret. Over hang the fret with this one and apply too much pressure and that ramp will have to me milled out meaning a lot of work taking perhaps several thou off from every fret to match the same level set.....

I can see this caul in use in a production environment for say Fender style necks where an Arbor press and a sled is incorporated but the sled will have to move in two axis an X and Y so it can pay attention to the fret ends.

Bottom line we prefer what we use Andy's caul set and we do have continuously variable cauls that Dave came up with but we don't use them because they don't work as well as the plain old static cauls that you can get from Andy. The issues I'm reporting here are from our cauls that Dave invented and we thought it was not ready for prime time, yet. Our's is a dead ringer for this one in many if not most respects and we played with this about 7 years ago.

I'll add that in the excellent film Hunt for Red October when they discovered that the drive on the Russian sub, the "big mother..." was a caterpillar drive the line in the movie was and I am paraphrasing "we played with that some years ago and could not make it work...." This describes our experience with a caul just like this one continuously variable.

My idea for one has not been pursued but remains very different from all of these. To me the only way to have consistent pressure the entire span of the contact area is fluid that will not compress. Hydraulics if you will.... Now who wants to invest the $100K in pursuing this for a market of 200 of them world wide, lifetime.... Guess my GE engineer is showing....

I'll add that Andy's set is different in the graduations specifically calculated and selected to do compound radius boards.

And finally no disrespect intended to the creator of this caul it's great but has the very same problems that our's did so we shelved our's favoring using Andy's caul set. By the way our continuously variable caul looks very similar to this one but we could not make it work to the point where it represented an advantage over what we do.

And really finally I applaud the maker of this caul we understand what it takes to bring this to market and it's often thankless and much more expensive than we had imagined. The lutherie markets are small, you guys tend to go to school on pictures and then make your own and even reaching break even is like nuclear fusion.... illusive.

I'm sure from looking at it and our's being much like it that it works. We simply found that what we do with static cauls for now suits a high volume, production environment where time is money better.

I’ve never used Jaws, but his website shows it being compatible. I put it in my drill press and it worked great. The problem I had with the stewmac cauls is the 16 didn’t seat the edges and the 14 didn’t seat the center. I had to finish hammering them in after so they were kind of useless for me.

The fractal does require multiple presses, but seated everything well. I filled the slot with medium CA glue using a pipette, then seated with my drill press (this would be hard with the neck attached to the guitar). Afterward, I rubbed accelerator on each fret with a brush, immediately after pressing it in.

For me, building a new guitar, it works much much better than Stewmac’s cauls.

I would like to hear as much as you can share about that fractal press as I am leaning in that direction, if you have time to spare.

Right we've never used StewMac cauls they are the wrong radius and don't include the necessary radius as you have found out. That's why there have been at least two aftermarket sets available in the last 20 years. The set From Andy that we collaborated with him on has graduations from one caul to the next of .5 and it is engineered to always have the right radius available even for a compound board that may start at 10 and finish at 14 or whatever.

You should be able to do all fret seating with the press we do. My hammer never gets touched and is the loneliest tool in my shop(s).

Our gluing is easier than your's. We press them all in and then wax the board with Howard's and then with a pipette wick in THIN CA which surrounds the fret tang and you can see right before your eyes the CA wet the other side of the fret tang from where you applied the pipette. Then we spray accelerator and move to the next one. If the frets are seated well (all the way down with no issues including the ends) we don't clamp before gluing. If they were problematic we again use the cauls and Jaws II to clamp each fret in place, wick in thin CA, hit with accelerator and move to the next one.

Regarding building a new guitar. This is the very same method we have used when we ghost built and did final assembly for some builders who I will not name. That's in the cone of silence

Anyway different strokes whatever floats your boat and there are always, well usually lots of ways to do the tasks that we have to do and once in a while some of them are even pretty OK.

Our continuously variable radius caul worked well too but we had to press more than once as well which defeats the purpose of greater speed and efficiency that we sought so for now we use our custom caul set and get great results and it keep my guitar collection growing nicely.