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I’ve been building slot head steel strings for my last several guitars. While I have a very nice jig for drilling the tuner holes and routing the slots, I still carve the ramps by hand with a round rasp. Has anyone come up with a fancy way of cutting the ramps? Not critical; I don’t mind doing it by hand. But if there is a nifty way to do it, I would be interested. Thanks for any input.

I do what you do. I don’t mind the carving so much but I hate sanding the ramps and slots. Good ideas always welcome.

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Steve Smith
"Music is what feelings sound like"

Steve--

Yes, for sure, sanding the slots (I don't mind the ramps so much) is a big hassle. It is made bigger if I slip with the rasp and bump the slot walls. I cover those with protectors, but they can still get dinged.

Somebody somewhere must have rigged up something that works like a Kreg jig, so you could just drill the ramps, then clean up with sandpaper. Something like that exists for cutting a headstock access hole for a truss rod, right? You should be able to do something similar for these ramps.

I use a dremal with a 120 grit drum smaller then the ramp width.
the dremal is variable speed

mike

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Mike Collins

That sounds interesting, Mike. I have a Foredom; I could use a small drum in a handpiece. So, it doesn't get away from you? That would be my fear.

I enjoy carving the ramps but I guess an angled jig with a core-box or ball-nose bit would get you most of the way there much faster? I rasp mine out with a very fine grain rasp and find it leaves such a good surface that it doesn’t take much time to finish sand them with fine sand paper stick on a small rod or cylinder.

For the slots, I cut them slightly under size with a slightly larger guide bushing and a jig and then switch to a smaller bushing for a final pass. With a sharp downcut carbide bit there is no sanding necessary - the surface gleams and takes finish well.


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I probably need to buy some new bits for my slot cutting; I had a little cleanup to do. But the bigger #$&*% moments are if I ding the slot walls while cutting the ramps. Maybe I need to mask those with aluminum flashing, instead of the plastic I’m using. It all comes out fine in the end; I was just curious if someone has gotten clever with a jig for this.

Don, what helps me is using a long enough rasp that I can reach under the headstock to hold the front of the tool as well as the handle, enabling me to prevent it wandering off course and touching the walls of the slot. Also, I don’t try to rasp the edges of the ramp all the way to their final width (ie the width of the slot) - I stop a thou or two shy and sanding takes me the rest of the way. So I avoid a situation where I’m trying to rasp flush with the slot wall.

I’m talking here about rounded ramps, square/flat ramps ones I don’t do but I imagine a flat file with two safe narrow edges would make finessing those relatively risk free…

And finally, I do have a set of fancy French hand-stitched rat tail rasps for this, which are easy to push and cut smoothly without needing a lot of force and this allows me a lot more control than when I used hardware-store rasps and had to really lean on ‘em.

I’m probably guilty of being too greedy with the rasp. It cuts great, so I want to use it to get the ramp just so. But I risk touching the slot walls when I do that. I use a pretty long rasp, and control it with both hands on both faces of the headstock, but yeah, I should probably not try to get everything with that tool.

Anyway, my curiosity is still focused on any jigs someone has cooked up. And now that I have gone and looked at the StewMac truss rod access hole cutter, I am even more interested in seeing if a pocket hole jig would work in this context. Has anybody tried that approach?

Round rasp for me too followed by a dowel of the appropriate size with double stick sand paper on it.

I have not but I guess that if you did, you’d get the cleanest result drilling the angled pocket hole first and then routing the slot.


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I use a #9 sweep gouge and a small Japanese razor file (the small curved one, stewmac sells it https://tinyurl.com/2xaef7bc) to hog out the bulk of the material, a small crossing file to cleanup/refine, and then a dowel with 220 on one side and 320 on the other for final clean up. Using a narrower rasp and file then the width of the slot makes it much easier to avoid damaging the slots (I never mask) and the whole process is fairly quick and painless.

I make my ramps squarish? flat? I don't know how else to describe them. I use an X-acto saw, mark the needed depth of the saw slots cut down to the lines holding the saw against the walls of the slots, then hog out the ramp with chisels.

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formerly known around here as burbank
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http://www.patfosterguitars.com

This is interesting. What comes to mind is the kreg pocket hole jig. Made so that it has the right spacing and angle. Maybe as an attachment that snaps onto the plate used to route the slots. Hmm….


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my Dremal is variable speed.

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Mike Collins

If doing the ramp round by hand, Brian's method, with the Stew Mac razor file sounds good. I bought a pair of round and flat years ago, as Iwasaki files. I have others too. They work great. I lost my round bottom one over a year ago, and just found it 2 days ago! The files cut nice. They actually cut, they don't scratch.

I've found tools in the trash, and in the chip bin. How they got there I don't know. This was sitting on TOP of the upper part of my go-bar deck! No clue about that either. I was standing on my toes to see it; and even then, the bracing blocked it, and the vacuum moved it around.

I haven't done a slot head yet. I have 2 plans that have them, a Panormo, and a Torres; but they both have square ramps like Pat showed. They should be easy with my planned, drill, saw, chisel, file, sand technique.

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Why be normal?

The vast majority of my guitars have square ramps instead of rounded ones. Aesthetically they're much more my speed as my biggest influence (at least in the looks department) is Torres. With that said I actually think square ramps are a lot harder to pull off. Any asymmetry is much more noticeable compared to rounded ramps and if the corners aren't crisp and sharp it just kind of looks sloppy. I also prefer to square the bottom of the slot like Torres or Hauser (pic below as an example), not strictly necessary and a rounded slot can look nice, the maker I apprenticed under did just that, but the squared off slot is a nice touch to my eye.

For the square ramp I use a very fine dozuki to cut about 1mm away from the walls of the slots that correspond with desired length/depth of the ramp. I then use a 4mm chisel to carefully remove the material slowly and methodically, a larger chisel seems more intuitive but using a large chisel will require you to apply more force/pressure making a slip up (taking a chunk out of your headstock) more likely. Once I've reached my final ramp profile I use a large chisel to par away the material at the sides of the ramp, making sure to mind the symmetry of the design as well as keeping the corners crisp and sharp. Once completed I use a sanding stick shaped to the profile of a Barrette file with 320 sandpaper glued to the bottom to clean and polish the surface of the ramp. It's very important to only sand in one direction as sanding back and forth instead of sanding forward, lifting up the sanding stick, resetting, sanding forward, etc. will cause rocking and unevenness.

+1 on preferring flat bottomed ramps. To me it's a cleaner look and there is more clearance for the outside strings in particular. I like the flat vertical face as well but I found it was extra work for little impact, other than a tribute to venerable old-time makers.
It's easy to make a wedge-shaped router jig to attach to the head and use a hinge mortising bit with router base collar to cut the facets. The jig indexes off the slots by having a tab that extends from the base that fits the slot precisely.

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Stay with the happy people.
--Reynolds Large

TRein, do you have a picture of your jig?

I've been thinking about this and not coming up with a simple solution.

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Brian R, Wood Mechanic
N8ZED

I'd be happy to if someone can fill me in on how to enable Tapatalk. I remember reading that by using this app and your phone's camera you don't have to resize the image first. I don't use an external photo hosting service and resizing images to 256K is hit or miss, at least with the photo editor I'm using.

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Stay with the happy people.
--Reynolds Large

Tom--

I am not versed in Tapatalk, but if you e-mail the photo to yourself, and pick "Medium" as the size of the photo, then store it on your hard drive after you receive the e-mail from yourself. it will fit here on the OLF when you go to upload it. This is a workaround I use all the time.

Flat ramp cutting jig.
Wedge could be made smaller if you feel comfortable with a router with a smaller base.
A 1/2" hinge mortising bit in router with 1/2" base template collar are used. A smaller wedge would be more versatile in terms of the length of router bit required.
The cutouts on the side are for small c clamps to hold jig to headstock. Obviously a backing board is used when clamping.
The wedge can be glued up without special milling. Thickness a board that is a tight fit to the slot and use 2 pieces: one to slide into the slot and index the jig off the top of the slot and the other piece to maintain thickness of wedge.
I wanted the jig to leave the ramp a wee bit narrower than the slot. A few passes with a sharp chisel will true the side of the ramp to the side of the slot. This accounts for inaccuracies between router bit and base collar. It would be big trouble if the jig cut the ramp wider than the slot.

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Stay with the happy people.
--Reynolds Large

another view

_________________
Stay with the happy people.
--Reynolds Large

Thanks, Tom! I have wheels turning in my head as to how to tweak this for my own use.