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ChuckBarnett
05-11-2018, 01:46 PM
So I have ordered fretwire for the tenor ukulele I'm building. From LMI it is the gold FW 37053. Looking at the information they offer I see that the total fret height is .094 inches and the crown height is .037 inches. The tang height itself, which translates to the fret slot depth, is not listed. But if you do the math subtracting the crown height from the total fret height you get .057 inches. That is less than 1/16 of an inch! Is that what I'm shooting for? Making a cut that's less than one sixteenth of an inch deep?

Insecurity is having me for lunch...

DPO
05-11-2018, 02:46 PM
So I have ordered fretwire for the tenor ukulele I'm building. From LMI it is the gold FW 37053. Looking at the information they offer I see that the total fret height is .094 inches and the crown height is .037 inches. The tang height itself, which translates to the fret slot depth, is not listed. But if you do the math subtracting the crown height from the total fret height you get .057 inches. That is less than 1/16 of an inch! Is that what I'm shooting for? Making a cut that's less than one sixteenth of an inch deep?

Insecurity is having me for lunch...

If you wait until you have the fretwire on hand you can then guage the exact depth you need and can experiment on some scrap.

ChuckBarnett
05-11-2018, 03:18 PM
That certainly is good advice. I was hoping to make a crosscut sled for the slotting process but wasn't sure how thik to make the platform. So I was working backward from depth of cut (i.e. how high above the platform the blade needs to reach...)
But if all one is cutting is less than a 1/16" then I should be able to get away with 3/4" for the platform. Just antsy...

Allen
05-11-2018, 03:49 PM
That looks to be about right. I cut my fret slots 1.7mm deep.

ChuckBarnett
05-16-2018, 04:15 AM
Okay, so I built a cross-cut sled and I got my fret wire from LMI and I found a piece of quilted Maple to practice on, cut a fret slot and pounded a fret in. Not knowing what I'm doing I'm obligated to ask for input. The fret slot is deeper then the tang as it should be, but I don't know how this compares. Meaning I don't know if it's too deep or it could be a little deeper or why? Open to counsel, wisdom, advice -all of the above.

Newbie Chuck

ChuckBarnett
05-16-2018, 04:24 AM
In preparing this fret slotting crosscut sled, I don't know how to determine where to put the registration pin for the template. As I understand the process, you tape the template onto the fretboard and register the template and fretboard against that pin, cut a slot and then move to the next position. How do you know where to install that pin?

resoman
05-16-2018, 05:23 AM
Check this vid out

https://www.youtube.com/watch?v=74r40X-oA7E

ChuckBarnett
05-16-2018, 05:53 AM
Thanks, Terry. I'd looked at that but he didnt address my question of where to locate the pin. How far from the blade and on which side?

Titchtheclown
05-16-2018, 11:33 AM
In theory it doesn't matter how far the in is from the blade location or which side except for the boring practical consideration of the fretboard falling off the template. My manual version has a registration blade and is in the cutting slot.
Not having built a table saw version I would put the pin about a thumbs width or less of the blade slot. To be fancy I would try and allign it so by lining the end of the template flush with the fretboard the top cut would be the width of a nut from the end of the fretboard.

To do this I would attach the template to a scrap fretboard (pine or ply or even MDF) flush with the end then mark on that where I want my nut slot., cut that by eye, turn the saw off, put the blade in the slot with everything on the sled and mark where the pin goes.

resoman
05-16-2018, 01:50 PM
Chuck, I do it differently as I use a sliding miter saw but the principal is the same. I just measured my registration pin and it's 0.700 from center of the pin to center of the blade.
0.700 or 17.78mm. I learning to use mm's these days

saltytri
05-16-2018, 03:10 PM
It's possible that you are overthinking this. :) Put the pin where it works for you. Here are photos of an 18 fret 17" scale board in a table saw carriage using the LMII template. The first shows it set to cut the end of the board square. The second shows it set to cut the 18th fret. It doesn't matter where the pin is, provided it allows you to position the board so that most of it is on the bed of the carriage at both extremes.


https://farm1.staticflickr.com/971/41439614374_594eff98f6_c.jpg

https://farm1.staticflickr.com/961/41259329275_9eb76ac9ef_c.jpg

ChuckBarnett
05-16-2018, 05:36 PM
It's possible that you are overthinking this. :) Put the pin where it works for you. Here are photos of an 18 fret 17" scale board in a table saw carriage using the LMII template. The first shows it set to cut the end of the board square. The second shows it set to cut the 18th fret. It doesn't matter where the pin is, provided it allows you to position the board so that most of it is on the bed of the carriage at both extremes.


https://farm1.staticflickr.com/971/41439614374_594eff98f6_c.jpg

https://farm1.staticflickr.com/961/41259329275_9eb76ac9ef_c.jpg

Thanks for your time and effort on this!

Not sure why you're cutting the end off square if you've already done that. (I watched Robbie O'Brien's LMI power slotting video. He said to cut one end square and butt that against the saw blade...)

So I still don't see how to determine the distance from the board end to the first fret slot.

ChuckBarnett
05-16-2018, 05:40 PM
In theory it doesn't matter how far the in is from the blade location or which side except for the boring practical consideration of the fretboard falling off the template. My manual version has a registration blade and is in the cutting slot.
Not having built a table saw version I would put the pin about a thumbs width or less of the blade slot. To be fancy I would try and allign it so by lining the end of the template flush with the fretboard the top cut would be the width of a nut from the end of the fretboard.

To do this I would attach the template to a scrap fretboard (pine or ply or even MDF) flush with the end then mark on that where I want my nut slot., cut that by eye, turn the saw off, put the blade in the slot with everything on the sled and mark where the pin goes.

Okay... I'm assuming that the nut is off the end of the fretboard. You're not cutting a slot for that, right? Or have I got this all messed up??

Titchtheclown
05-16-2018, 06:25 PM
Okay... I'm assuming that the nut is off the end of the fretboard. You're not cutting a slot for that, right? Or have I got this all messed up??

I always more or less mount my nut in a rebate at the end of my fretboard. Feel free to cut all the way through but dont usually guess where it is going to be and just cut slots for the frets as unless you are super good at lining things up that is asking for trouble.

Wildestcat
05-16-2018, 09:53 PM
I recently built myself a sled for the table saw using a 0.6mm blade from a German supplier - much cheaper in the UK than buying from the USA. I'll dig out the details if anyone is interested. I use non-standard scale lengths, so cut my own templates using the Hosco 0.6mm fret slot saw I had used previously to hand cut slots. My "pin" is a ground down Stanley knife blade which is exactly 0.6 mm thick, located just to the side of the saw line. I cut the nut slot (zero fret) to the same depth as the rest, then later cut through the board end with the cut encroaching into the zero fret slot. I try and leave ~0.1 mm so I can accurately trim back to the slot edge on the disc sander. The nut then sits on the flat part of the neck butting up to the FB end, effectively in a "slot" created between the FB end and the headstock veneer. I use small pieces of double sided tape to hold the board onto the template.

109008 109009 109010 109011

My table saw only has one mitre slot, but a very accurately machined table, so I chose to use the outer edges of the table to register the sled. A few strokes with a wax crayon on the wood strips and it slides easily with no wobble at all. I'm very pleased with the way it all works.

Link to the blade I bought: https://shop.rall-online.net/epages/61511639.sf/en_GB/?ObjectPath=/Shops/61511639/Products/04080016

They do several different sizes, but the great advantage for me was the 30 mm arbor size which meant no messing with adaptors on my saw.

Goodness
05-18-2018, 06:43 AM
109048 hey you are doing well. Look at this monstrosity I made for. Freting on my first ukulele.

Goodness
05-18-2018, 06:45 AM
I try to be the Macgyver of Luthiery109049

Beau Hannam Ukuleles
05-18-2018, 08:27 AM
If you wait until you have the fretwire on hand you can then guage the exact depth you need and can experiment on some scrap.

Yep-
Also, add a touch of depth to compensate for later sanding etc.

ChuckBarnett
05-18-2018, 08:51 AM
Later sanding? With frets installed?

ChuckBarnett
05-18-2018, 11:06 AM
Thank you for the encouragement! :-) :-)

Beau Hannam Ukuleles
05-18-2018, 11:48 AM
Later sanding? With frets installed?

no- I slot, then glue the FB on, then sand level etc, then fret.

Beau Hannam Ukuleles
05-19-2018, 05:49 AM
Also, if you radius the fret board, you will have to cut a deeper slot to accommodate the lost of wood on the FB sides.

ChuckBarnett
05-19-2018, 07:13 AM
no- I slot, then glue the FB on, then sand level etc, then fret.

Thank you, Beau. Hmmm... never having done this before, I think I might have overlooked an important step. I sort of thought this fretboard was fairly flat, but you sand it after you cut the slots. You don't put the frets in before you put it on the neck. You taper it before you glue it on? I assume you start with something like 150 grit and go up from there. End with... 320 grit or so?

Beau Hannam Ukuleles
05-19-2018, 09:30 AM
I thickness my FB's to 5mm,
Then slot,
Then shape,
Then glue the FB to the neck,
Spray the finish,
Glue neck on,
Then final sand the FB as I always get a slight hump over the body which has to be removed before fretting.

Some fret before gluing the FB on, some fret after glueing the FB on but before finishing.
Neither is the more correct way- the only correct thing is the end result which is to not have a hump where the neck meets the body.

Allen
05-19-2018, 10:32 AM
Lots of builders will install frets before the fret board is attached to the neck. Reason being is that the frets at the upper end of the fret board will in most cases be over the sound board with little support underneath for hammering them in. You have to take special care in that area.

I've always installed frets before the fret board is glued to the neck.

ChuckBarnett
05-24-2018, 02:07 PM
Once I finally caught on that the nut end of the fretboard has nothing to do with the location of the pin in the crosscut sled, I was able to move ahead. Once I figured out that you are going to cut the fretboard off at that first slot (which I finally understood to be the nut slot), i understood that you could put that pin anywhere so long as you leave a quarter of an inch or so beyond where the blade would cut that nut slot. So I set the pin up about a half an inch to the right of the saw's path. I feel that my natural inclination puts the nut end to my left facing the saw. I cut 19 fret slots per the LMI plan. And I am pleased!

Thank you, all, for your patience with me!! Seems like everything along this journey looms very challenging. But looking back on it I see that it isn't rocket surgery. ;-)

Beau Hannam Ukuleles
05-25-2018, 09:05 AM
one last tip, if your jig is like mine, it is able to cut more then 19 slots.
So you don't accidentally cut 20 slots, start at the 19th slot and work towards the nut end.- Fool (almost) proof!

ChuckBarnett
05-25-2018, 09:36 AM
one last tip, if your jig is like mine, it is able to cut more then 19 slots.
So you don't accidentally cut 20 slots, start at the 19th slot and work towards the nut end.- Fool (almost) proof!

GREAT TIP!!! Us fools can use all the tricks 'n gimmicks we can find, no? :)