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Hi All,

Here is a quick and cheap attachment I’ve made to rout bindings. It’s not on the same level as Don William’s or Mark Kett’s stuff, but it was cheap and fast to build and did the job. I designed and built it in about an hour and a half one evening and then tweaked it for about an hour the next evening before I used it. It uses a piece of angle iron, two ? x 20 carriage bolts with nuts, and a piece of hard/slick plastic. The base on the Porter Cable lam trimmer provides the height adjustment, and the carriage bolts determine the depth of cut. I aligned them parallel to the face of the router bit and then filed a small notch in the threaded end to keep them in alignment. Since they have 20 threads to the inch, one turn equals .050”, and if you think of the face of a clock, turning them from, say 3 o’clock to 4 o’clock, changes the depth of cut approx .004”. The angle iron is threaded and each bolt uses a jam nut to keep them locked in place. I smoothed the heads of the bolts to avoid scratches. I got the PC 7310 on sale for $70 and had the scraps lying around, so for the money, I’m pleased with the results. You do have to pucker tightly when making the final pass and keep the bolt heads firmly against the guitar sides. I didn’t use any jig to hold the guitar body while routing – I just used my radius dish, non-slip shelf liner, and threw a small sandbag on the guitar to hold it steady.

Results - My guitar back with a 15’ radius and tight waist needed a little clean up work (10 minutes with chisel and sandpaper) in the waist and upper bout, but the top ledge routed out fine with just a quick swipe with sandpaper to get the fuzz off before gluing in the binding. My bit is kind of dull, so I did the job in two passes.

Anyway, I know the pros here won’t get much out of this, but hopefully this will help some of you low-budget lurkers. If you have any questions, just ask.

BruceH

Hat's off to you Holbrook, very neat contraption. Send it to me and let me try it. I'm backed up on binding jobs....

Bruce, nice work. When I saw the pic my first thought was, "gosh, how the heck can he determine how deep the cut will be"? but you addressed that issue well. One thing you might think about doing is putting a wing nut on the other side of the iron that can lock the bolt into position. I would think vibration from the router could possibably work the nuts loose and cause variation in your depth of cut.
Good job! Paul

Bruce, do you have a locknut to retain the adjustment on the rub-bolts? I love carriage bolts in the shop, so versatile with the full length thread. Major kudos on this setup.

Second Question: What is the bracket you are using? Is it just scrap?

Under Frets.com and one of two field trips Frank Ford makes to Fox Guitars, they have this very thing, all made of the dense plastic, you've really made a quantum leap making both upper and lower positioners adjustable. Now if they just had ball bearings on the end. Super job Bruce, I'm impressed and sure glad it works so well. Dickey38418.4143287037

Bruce, it looks good. Have you thought about putting some uhmw plastic tape on the bolt heads? I bet it would make it slide easier and add some extra protection.

_________________
Don Atwood
Arlington, VA

Elegantly simple!
Nelson

Thanks for the comments, guys.
Paul and Bruce- You are right about needing lock nuts to keep the adjustments locked in. I mentioned in my text that I used jam nuts, but it's not obvious from the photos. The metal angle iron is threaded and then I have a nut on each bolt that tightens against the angle iron to lock the adjustment in place. Paul, a wingnut would make adjustment faster, but I'm not sure if I could get it tight enough to suit me.
Bruce, the bracket is just a piece of angle iron that I scrounged from my dad's junk pile.

Don, the uhmw tape is a great idea if it will stretch enought to cover the rounded heads without wrinkling. I've never seen or used any, so I don't know. Does it stretch much and still retain its adhesion? Bruce's suggestion of ball bearing tips might work too, but the whole friction thing really isn't much of an issue. I could spend hours redesigning it to perfection, or I could just grab it and rout another guitar

If anyone wants anymore info or pics, let me know.
BruceH

[QUOTE=BruceH]   I could spend hours redesigning it to perfection, or I could just grab it and rout another guitar
BruceH[/QUOTE]

Better is the enemy of good enough. When you used it, did it feel pretty secure? Since the bolts have a bigger radius than the cutter, it should be self correcting. It's a really good idea

I liked it enough to print out this entire page. I have an idea of a little gear on each bolt shaft with a tiny crank on one. When you turn one, you turn the other, exactly the same amount. Really in this plane, little adjustment is needed, how deep is herringbone or pearl?

EricKeller wrote:
"When you used it, did it feel pretty secure?"

Yes, the thing to pay close attention to is to be sure that both bolt heads stay in firm contact with the guitar side. If the bottom bolt comes off of the guitar side then the router tips in and cuts wider than intended, and if the top comes off the side the cut is narower. Not hard to keep both in contact, but you have to watch what you are doing.

Bruce, if you build one with gears and ball bearing tips, post some pics What are you using now?

I have a couple of DW670 Dewalt Trimmers with the bearing followers. And I have a GuitarJigs.com binding setup, but will have to change my dovetail cutting before I can use it.