How To Cut Custom Not-So-F-Holes

[Otsismi]

I've been inspired by the work of Chris Verhoven and David Myka, especially in the semi hollowbody realm. My current build is a chambered ash body and a 1/4 in maple cap. I've been trying to cut the f holes in the maple, but the sharp corners are proving to be extremely difficult. How have others done something like this in the past to achieve uniform, smooth, and sharp looking results? This was extremely hard and I'm not very proud of it.

https://lh6.googleus...-p-k/2013-02-12

[ScottR]

You have to clean the corners up with an exacto knife or something similar, and the curves with rasps, files, sandpaper and so on. The clean up is part of it. Don't feel bad......you're just not done yet.

SR

[verhoevenc]

^ Exactly.

Chris

[Mattia]

Sharp edge tools FTW. I use a 'violin knife' (bevelled edge carving knife made by Pfeil), various scalpels and paring chisels (long blade) for this type of detail work. The final bits are the biggest pain in the ass.

[Prostheta]

Funny you should mention scalpels Mattia. I always comment to Nina as to the equivalent blade in the Swann & Morton range whenever I see a scalpel on TV. Sad! Still, for f-holes I think a trusty 10A would do pretty much everything with an 11 perhaps coming in a close second for working in tight corners and radii.

I recommend walking into your nearest arts and crafts store and demanding in a firm tone of voice, "stout yeoman I insist that you supply me with a brand new B3 stainless steel scalpel handle, two foil packets of 10As and one of 11s, thanking you ta".

Those Pfeil knives have been tempting me for a while, Mattia. I doubt I would get the mileage out of them at this stage however....still....

Also, Otsismi - I noted that the top on that body showed quite a thickness of wood around the f-holes. If you further relieved the carve around the back of the f-holes down to a few mm (even if it is just a perimeter around the f-holes than anywhere else to simulate a thinner top) then you have far less material to shape making your work far easier to achieve. Cutting a sharp corner into something with a thickness of 10-12mm (visual estimate) is many times more difficult that doing it to something 3-5mm thick.

[guitar2005]

Yes, it can long and tedious to get nice f-holes. I've done a few but when working with maple, it can be really time consuming, especially with a thicker top.

I've gotten by with homemade sanding sticks and small files but recently, I got some scroll saw sanding belts and that has given me the best and quickest results so far. I get mine from here but many places have them

http://www.leevalley...465&cat=1,42500

Of course, that requires a scroll saw but they can be found for pretty cheap on the used market. I use my scoll saw for inlays, truss rod covers, cavity covers, f-holes, template work....

I just take my time, apply little pressure and let the sanding strip do the work. Also, If I have say a 1/2" maple top, I rear route the top around the f-hole so that the thickness is reduced to 1/4" or less. Its visually more pleasing and easier to work IMO.

[Prostheta]

The revelation I had recently was sharpening knives and chisels on the Tormek. Previously my biggest bugbear was cutting tools ending up splitting the grain by following it from (relative) bluntness. Now I am confident in paring endgrain and cutting grain slightly off its direction without splitting it using light pressure only. To extend what Mattia said about "sharp edge tools"....there is a world of difference between reasonably sharp (you can scrape hairs off your forearm) and truly scary (you can slice off half your fingernail without effort). Surgical scalpel blades are fantastic as long as you understand and can counter their flex. Those Pfeil knives look more and more attractive all the time the more I think about this.

[verhoevenc]

Oh, sharp tools are a KEY aspect to ANY shop! Here's the BEST method I know:

Part 3 (wet stones) is the way I use. Warning: I am biased, I filmed the video and the guy in it is a good friend of mine. However, unbiased, I've still never met anyone with sharper tools than he.

Chris

[Prostheta]

Some people spend a lot of time sharpening instead of working!!

[Otsismi]

Yes yes I remember the first day I met you and Todd at his house down the road from mine. I had butchered a piece of poplar with a very blunt chisel. I have since adopted the scary sharp method and have since cut myself many times lol. Invaluable instruction. I think a chip carving knive would help with this work as the blade is strong and can be sharpened easier than a scalpel but I find the task a bit daunting as that I have never used a strop. Any experience to share?

[verhoevenc]

Bah hahaha. Hey Tim! You gotta sign out with a name so we know it's you!

Stropping I got nothin' on. You'd have to talk to Todd on that end.

And yes I realize I still owe you a template making day. The guy I was going to pair you up with didn't work out. But I AM going to have to do some templates soon for a sort-of commission if you still want in.

Chris

PS: Holy s**t dude, that build up there has come a LONG way from the poplar body. Color me impressed!

[Otsismi]

I def still want in. I've gotten a lot better at templates myself. But learning from a master is always a plus. I've also picked up a bandsaw, jointer, planer, router, and drill press. The build above is number 3, poplar body being number one.

[Otsismi]

https://lh6.googleusercontent.com/-YB12kFVxVRI/USAKr3OqlCI/AAAAAAAADco/GVf4mxu32qc/w795-h804-p-o-k/2013-02-16

Here's number 2

same wood as number 3