how would you model slots in a fretboard?

[RobSm]

Hi.

I'm learning Rhino 3D.

So I have a fretboard modelled,  tapered radiused - compound no less - and all the fret positions for a number of scale lengths to hand.

Do I make in modelling terms the fret line the centre of a .023" dado ie slot? Will the model programme go so low? Are there settings to be changed? workarounds?

Thanks,

Rob.

 

[demonx]

I don't CNC the slots as it'd take too long being how fine the cutter has to be you need to slow the feed rate right back so it doesn't break, so I cut these on a radial arm saw using a template and pin locator. Takes about a minute or so.

IF I was to model the fret slots, which I do when I'm laying out inlays, I'd simply draw a line at the exact location and then program in the CAM for the cutter to follow that line. It doesn't need to be drawn in the CAD as a X wide and Z deep hole. it just needs to be a line that the CAM can locate, the cutter size will determine your slot width and your programmed depth of cut will determine the slot depth.

[RobSm]

thanks for the info.

I was wondering about the wisdom of it since on the table saw with a template and jig it's no big job.

I'm just learning all the processes ie cad/cam at this stage.

I'll play with the lines.. :o)

Regards,

Rob.

 

 

 

[demonx]

On 2/27/2016 at 10:16 AM, RobSm said:

thanks for the info.

I was wondering about the wisdom of it since on the table saw with a template and jig it's no big job.

I'm just learning all the processes ie cad/cam at this stage.

I'll play with the lines.. :o)

Regards,

Rob.

 

 

 

 

Yes and no, it's a a big job if you have to set up the saw every single time, change the blade etc etc, if this was the case I'd rather just use a stewmac mitre box and do it by hand.

 

However if you have a dedicated saw, not a drop saw or a compound saw or any of that stuff as they flex too much, a radial arm saw is ideal, the old solid ones that were quality built and you can pick up cheap for a few hundred bucks. Get one of those and set it up permanently for for that job and then slotting is a quick and easy task.

[Aeleus]

Using the CNC to do frets is not the quickest way, but it does have a couple of advantages. 

1. The slot can have a constant depth that follows the radius. A minor advantage admittedly.

2. You can create blind cuts that end before the edge of the fret board.

[fairyforest]

Hi Aeleus.

I love the idea of blind cuts. In combination with the hemi-semi fretting in the tutorial section it should be an awesome fretwork!

Since I have no CNC machine I thought of making a fretslot template based on my libreCAD drawings and than cut the frets with my Dremel tool using a fine router bit.

My question is now what kind of router bit are you using and from where can I get it?

Another alternative I have in mind is cutting normal slots and afterwards bind the fretboard with the same wood type it's made of. I saw that in a Youtube Video at CrimsonGuitars and he said it helps to avoid shrinking when you work with Ebony.

The result would be quite similar, but your solution is more elegant.

Enjoy.

[Aeleus]

FairyForest,

Before I started doing the blind cuts, I cut the fret tangs a bit short and just filled the slot ends with sawdust and glue. It's virtually invisible with a dark wood like ebony.

Since I started cutting my own slots with the CNC, I can just stop short and save myself the trouble.

Binding with the same wood is an interesting idea, but I'd probably do the filler first. Even if the filler shows (like on maple), it's better than having fret tangs sticking out.

As for the bits I use, I've happy with the selection from precisebits.com. They have a section for luthier tools. I got the .023" bits to match the fret wire I use. I suggest getting at least 2 or 3 bits - they are quite delicate.