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Keith Mackenzie developed this. I decided to build one. Here us my first attempt










I'm ok with the cut so far, but it looks like I will need to gap fill. Maybe it's the pencil grinder I am using? Harbor Freight? Bearing issues? Should I go with a Sioux grinder?

Forgot to mention that I am using a 1 mm guide pin and a 1 mm bit

Mike

yeah it could be runout on the grinder or it could also be that one or both arm that hold the grinder or guide pin vise is out of square or off plumb. That could be a problem too the farther away it is from the surface the greater the angle might be but runout on those HF pencil grinders can be pretty bad sometimes. You should be able to feel it vibrate, the one I had vibrated enough to loosen the collet. But check the the plumb also make sure the plated are booth all the way down also.
And a "Happy New Years to ya!"

Have you tried the Souix grinder? I am suspecting bearing runout.

I guess, undere ideal conditions, I was wondering if you saw a pretty good match to the template.

Everything else looks good, so I am suspecting the grinder.

Mike

Yeah, I threw the HF in the garbage and bought the black one from John Hall.
Cheers!!!

Ok Chris. Will do. Can see ur more in The mood for fun!

Happy new year

Mike

I would agree with Chris the HF units are not very good.
It is possible to compensate for some of the runout by using a slightly larger guide pin.
Also, don't try to cut more than 0.5 mm depth at once especially with the HF grinder as it will aggravate the runout.

Bottoms up Chris.
Keith

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Keith MacKenzie
Location: Florida
"To err is human to really screw up you need tools"

Same to you Keith !!!

Alright. Point taken. I will buy that black Souix grinder. Bottoms up and Happy New Year!!



Mike

I've been "under the weather" for about 3 days... so ya gets what ya gets

I'm nursing a cold and chasing with hot tea and honey, probably be in bed by midnight. Don't tell anyone...

Hot tea, honey, and Jack, Jack! Oh how I wish this crud would move on....

Blah. Happy New Year !

Switched out cheapie router for Souix 74K RPM provided by John Hall. Btw, this bad boy requires super dry oiled air. So I added a new dryer plus a silicate dryer. You'll know if u screw up here.



I cut this with a 3/32 bit. Probably better if I use a 1/32 bit (for the corners). Turns out there is a technique for doing this right. Simple, but for some reason it was not obvious to me at first.



So, I'm gonna order some 1/32 bits to sharpen the edge and practice a bit more before I hit the ebony with it. Gonna need to order a similar pin from
McMaster Carr (or it won't matter). Start with 3/32 to "hog" out, end with 1/32 to sharpen corners. Still have to work out proper registering to keep things centered.

Mike

Well done Mike!
Keith's pantograph grabbed me way back when I saw Chris's original video... screen-saved a bunch of pics at the time in case I ever tried to build one. (I was kinda hoping someone would post specifics/construction details.) You've reawakened my interest.

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Dave
Milton, ON

I made my MacKenzie machine copy a couple of years ago. Right after I first saw Chris's video.

Used wood from my scrap box and simplified it a bit. Both the router bit and the guide pin on the same flap. I think that reduces the chance of slop and flex in the system - even with the racked hinges.

I made the guide pin from some steel rod - used a grinder and a file to cut it down to the size of the router bit.
The system works great for me. I use it for most of my inlaying. I've had no problem with the Dremel bearings. If I start having problems, I'll switch to the grinder that I bought from John Hall.

Dave,

Mine is a little "over built". I thought it would help with stiffness. I was wrong. I am going to go back and build the top two layers again. Perhaps with Baltic birch if I can find some. I want the whole upper section to be lighter. You need enough mass to keep the router side down, that is all. I am going to refine the template part as well. I used 14 and 16 inch drawer slides from Lowes. Heavy duty. Here is what I would do different. Cut the end piece that all four hinges attach to. Attach that permanently to the end of the carrier base. Cut the two hinged boards that you see in the picture. Now temporarily screw these to the carrier board, all butted up tight. Get it all squared up on the jointer, etc. You most likely will need to rout out a small channel along the hing line so hinges sit flat (bowl bit). Now, attached "wracked" hinges. Remove temporary screws.

BTW, I discovered a very simple way to raise and lower the router bit depth. Something like playing cards between the hinged board and carrier base! I did not understand why there were two hinged boards, but I see that now.

BTW, the hinged boards can be locked together if you want to do some 3-D relief cutting.

Mike
We'll just have to agree to disagree about one vs. two hinged sections. I'm not changing mine cause it produces good inlay cavities for me. Took a bit to get the process down for making the Friendly Plastic patterns without holes and bubbles.
Here are a couple of my recent inlaying efforts.
Dan

Great stuff guys!
Mike, thanks for the improvement tips.
Dan, your version obviously works beautifully.... anyone know who carries "Friendly Plastic" in Canada?
Filippo, I do rough duplicarve the arches, using my version of John Sargent's Duplicarver. I used plans avail. on MIMF (just checked...still in library). Not CNC accurate, but well within limits for roughing. I think this is very helpful for both outside & inside archtop plates. (Unfortunately, my last one finally fried my old orange 5.5amp B&D router, so I'm looking for a replacement.)

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Dave
Milton, ON

I abandoned Friendly Plastic for my templates due to shrinkage distortion. I ended up using a plastic casting kit with flexible and rigid 2-part polymers. Very accurate.

Barry,
I am just beginning to use the duplicator and although I am reasonably satisfied with the friendly plastic I would like to explore the plastic resins. What do you use?

Thanks

Ron

Friendly Plastic - shrinkage distortion!!??
Maybe that's why I had to cut my guide pin thinner than my router bit to compensate for a very tight cavity.

Barry - Where did you get the plastic casting kit? And how easily does it release the MOP piece you use to make the form?

Dan

Wood screws (& washer). I bandsaw the plate perimeter with tabs, then drill holes through the tabs (matching screwholes in the table) for holding. (I'll then use a slotcutter on the router table to create a 1/4" lip around the plate as a target when duplicarving.)

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Dave
Milton, ON