Not many post-receipt comments on Roger's thread RE the KM-1 kerfmaker. A lot of hype before they released it but after they were released most went silent other than a couple who said they received theirs.
Bridge City Tool Works - KM-1 KerfMaker Pre-Order

I received mine and tried using it no avail on my OF1400 with guide rail. Where I perviously used John Lucas's tip with the playing cards ( Good Idea:* "Making dados to fit any width panel." ***** Page 1 ) I was using a 1/2" straight bit to cut a ~3/4" dado. Since the bit was exactly 1/2" wide, I used a 1/2" key-slot bar to calibrate it. After several attempts, the kerfs were either too wide or too narrow. I was right in the middle of a project so I decided to put it down until I finished.

Last night I picked it up again and began experimenting with some scrap on the table saw. This time cutting dados for ~1/4 plywood for drawer bottoms. Same thing. Either too tight or too wide. I calibrated the saw blade using the 2nd method described in the Youtube video.

I'm hoping it's just me and I'm doing something wrong. I want to figure it out before my 90 days run out so I can return it.

Looking for others who could add a review and maybe throw some tips my way. I bought this thing to save time but I know I can do it faster using my trial and error method.

I don't have one Jim but it could be a matter of squeezing more or less during one of the setup adjustments.

I do know it's designed to produce an exact fit so it should produce very tight fitting parts. If the cut parts are fuzzy they might not fit together.

I pre-ordered mine, but alas it hasn't arrived yet. When it does, I plan on putting it through some paces with a shop base where a screwup doesn't matter as much.

Jim

I have the kerfmaker and it works well for me - Most recently, I used with a kapex to cut some 90-degree cross lap joints for a cabinet and they were dead-on accurate. I did not follow the youtube video but instead the printed instructions. Don't have in front of me, but basically I did this:

- cut a kerf with the saw in a piece
- cross cut the piece to measure the actual kerf difference versus the original width and set the kerf maker to that dimension from the edge

This sets the kerf width.

- then used the kerfmaker to index the width of the half lap piece to measure the actual width I wanted for the dado / lap
- tightened the stop at that width
- laid it on the kapex table against a stop board which was clamped to an extension fence.
- cut one kerf
- flipped the kerfmaker
- cut the other kerf
- used the saw to clean out between the two
- fit was dead-on accurate for me

- repeated for each lap joint - eight in all

In my case, I used the saw to measure the exact kerf width. It sounds like you assumed a width on the router bit, and that could have introduced some error, but nothing like what you are suggesting. Somewhere something slipped.

Just found the video on youtube and watched it. It's pretty much the exact procedure I followed. I did not use calipers to set the kerf width.

good luck -

neil

Neil, On the table saw setup, I used the same procedure as you did. I can't even imagine doing it with caliper. How can you move it within a thousand of an inch by hand! I got the same results as I did with the router setup. BTW, My digital caliper showed the straight bit to measure dead nuts .5".
I must be all thumbs. So far not impressed.

Mine's arrived - but at a friend's in New York. By the time it makes its way over to Europe I hope you guys have decided how to use it and that I didn't waste 150 bucks - I bought my friend one as well
I'd like to get their saw but getting that across the pond might be difficult.

Richard

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I think I now have TOO many Festools to list

Jim,

I haven't had the chance to try my kerfmaker yet but it seems to me it would be difficult to adjust the table saw fence up to it easiy and accurately due to the heft and weight of the fence. Seems like it could easily bump the kerfmaker and change its adjustment or not quite touch it precisely. Again, I haven't tried it. When I first watched the video, it looked to me to be more appropriate for use on other tools where your sliding the small workpiece up to the kerfmaker which has much less mass and can be set gently.

Have you tried it yet with your miter saw?

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Wayne

Kapex, Domino, Trion PS 300, RO 150, ETS 150/3, Deltex 93, 2 CT 33's, OF 1400, MFT/3...

I was playing with John Economaki's kerfmaker at the WIA, and I was amazed at how tight you could lock it down. It wasn't moving anywhere. I think John's idea was that you would set it once, and leave it for all eternity. You'd have one for each blade (all labeled, of course - you can write on the kerfmaker with a Sharpie).

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I don't have as many Festools as Fred. Or Marcou's, or Brese's, or Lie-Nielsen's, or Lee Valley's, or Blue Spruce's, or Harold and Saxon's, or...

I think mine is about to be shipped; at least they charged the other half to my card yesterday. I also noticed they are taking 50% deposits on the JMP-V2 now.

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Water separates the people of the world; wine unites them.

My kerfmaker was shipped to Dave Ronyak from the FOG in Ohio, but Iv'e been in Texas since September, so I haven't even got a chance to see it yet. Everything I have ordered recently is being delivered to Dave until I get to pick everything up. I did get my order in for the JMP as well.

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Wayne

Kapex, Domino, Trion PS 300, RO 150, ETS 150/3, Deltex 93, 2 CT 33's, OF 1400, MFT/3...