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Hey everyone,

I've been wanting to upgrade my circle cutting jig for so long and finally had a need to get it done- It came out nice enough that I wanted to share some pics of it.

It is pretty basic in design, the main carriage rides on 2 rails and is powered by a central screw. There is an extension off of the front with bronze bushings that rotate around a 1/4" pin. The long ball headed lever is a locking mechanism and the indicator measures the travel.

It will cut from a 1 1/4" to an 8 1/2" circle which should cover just about any rosette related needs and then some. I was so glad when Bosch finally came out with a plunge base for the Colt. I knew that the Dewalt had one but wasn't excited about having to buy a whole new router. Building it around the plunge base (and not having to also build in a downfeed for the router) made the project easier to tackle and I can't wait to put it through the paces.

Thanks for looking!

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Burton
http://www.legeytinstruments.com
Brookline, MA.

Beautiful piece of work!

well, ya gotta like that!
Nice design. Mine is sort of like that only I use gauge blocks instead of an indicator to make adjustments. I've been meaning to upgrade to an indicator for about 20 yrs now. Maybe someday, but I doubt it if my track record is any indication.
Really a nice job Burton.

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Jim Watts
http://jameswattsguitars.com

Nice work, Burton. Your designs and executions have always impressed me.

Pat

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

That's great, Burton. I'm going to school to be a machinist and I hope I can make something that nice one day!

Snazzy! The micrometer is a nice touch.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Sweet! Well done, Burton, as always.

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George :-)

Drool!

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Beautiful piece of work Burton.
Does the Bosch have a fine depth adjustment?

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Very nice work. What lathe and mill do you have?

Thanks for the comments guys! I appreciate it.

Colin, it does have (a sort of) one on the rotating stop for the depth rod but just having that is better than the wonky screw downfeed on the non-plunge base that I used before. I am very excited to be able to quickly enter and exit the cut with the plunge feature, I have always wanted that. I expect that I will follow Jim's lead and use my gage blocks to set the depth of cut after leveling off on top of the spruce. That sort of precision in terms of the depth of the channel will be very welcome too.

Gary, I have a 3/4 size Clausing mill and a (very) old Hardinge lathe at home. They certainly could have made this tool but I took advantage of access I have to some newer tools at work and mostly used those. Specifically a ProtoTrak K2 mill and a newer (but still old) Hardinge TFB-H.

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Burton
http://www.legeytinstruments.com
Brookline, MA.

Beautiful work - Mike

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guitarsbygiltzow.com

Nice Burton....

I would like to have that if for any reason just to look at it, hold it and play with it. What a superb looking machine.

Beautiful work. Doesn't matter what it might be, it's nice to see anything well made.

Hey Burton,

Nice work. I really liked the way you designed the pivots to be in the center and added some outrigger mass to balance the weight. That extra length allows you enough room to easily mount the indicator too. Where's the rotational auto feed?

That's some next level action. Can you make the width adjuster knob go on top with gears and a big star knob? 'Cause with enough repeats, the tele knob gets angstful...

Very nice looking rig, Burton. I have also been waiting for the Bosch plunge base. However, in this application the plunge base seems a bit overkill, since we only need to plunge 40 or 50 thousandths. I overcame the need for the plunge base by using a couple of top cutoffs to hold the router above the plate. When I am ready to cut, I pull the cutoffs out and let the router jig settle into place and start routing. The benefit for me is that I don't have to keep resetting the depth. Leaving the depth setting locked in place eliminates another potential for slop/error.

Thanks!

Tim,
I was hoping you would chime in. About the rotational drive I was thinking I would go low tech, mount a sail and mast and strap a big fan to the other side. Waddaya think?

Ed, That is exactly what I had hoped to do- In the interest of getting it done though I didn't follow through and just made the smaller knob. If I ever come back to it then a set of miter gears are the next thing to install and a nice big dial on the top where it is easy to access.

Barry, You are right of course, it is a bit overkill. You could argue that the whole thing is! I've been doing something similar to you with my old setup and while it has worked fine I won't miss it.

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Burton
http://www.legeytinstruments.com
Brookline, MA.

The more work I have to do, the more overkill I want to get.

Me
I would have just taken a picture of my hands

incredible work of art !
and a needed one!

Mike

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Mike Collins

Beautiful tool Burton!
Every plunge mechanism I have laid my hands on, including a $400 Festool, has an annoying amount of play in the slides, allowing a lot of racking. Is that Colt base pretty tight? or is the play just not relevant in use?

David,

Hmmm.. I have had the opposite experience with plunge bases, I haven't used one I thought had much, if any, slop. The Bosch base feels great, tight and smooth. I haven't actually made a cut with it yet, though. We have the Dewalt laminate trimmer with a plunge base at work and that one feels great, I have had no concerns when using it.

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Burton
http://www.legeytinstruments.com
Brookline, MA.

The dial indicator