A Story of Lynn's Box Joint Jig and a Better Idea

After watching the video ( http://www.netexperts.cc/~lambertm/Wood/lynnjig.html ) I decided it looked great and fun and so I built one. That is where the trouble started. :)
The first thing I realized is that my Forrest WWII 3/32" blade cuts a kerf .105 thick, not .09375. Well, that equats to 3.38 turns of the handle for a blade width instead of 3 turns. Have you tried to turn .38 turns over and over and not lose track of where the hell you are? It ain't easy.
So, plan B is implemented. I load the dado stack and tune with shims to .250. Now all I have to do is cut, turn 16, cut, turn 16, etc.... Yeah right. I built my jig out of 7/8" thick white oak. There is no discernable side to side play in the threads and yet it will not cut joints to my satisfaction. Additionally, If you get lost on your way counting to 16 for the umpteenth time, you have to try and rezero, which means backing up, adding the slop back into the mix and it never comes out right.
I was also trying to save time by cutting a set one way then cutting back the other way with another stack of wood. Well, you get used to turning int one way and then find yourself going the wrong direction and losing count on how to get back.
I trashed a pile of good maple today, after having precisely cut and planed it till I got fed up and figured there must be an easier way than this jig. I was fully aware of the indexing jigs with the keyway but most of them only cut one board at a time, are still susceptible to accumulation and slop errors. I wanted something even better.
They say necessity is the mother of invention. I love the simple ideas and should have known that Lynn's jig was too complex. Here's what I came up with, and I've searched the internet and I've never seen anyone recommending this method. Surely it has been thought of before, but I haven't seen it.
I thought, with a 1/4" box joint, I need an accurate way to move WXACTLY 1/2" after every cut with my 1/4" dado. How bout I rip a 1/2" strip of hardwood and cut it into the number of box joints I need so I wind up with 8 - 1/2" strips about 6" long. Realize, when I say I ripped them 1/2", I'm talking 0.500 as measured by my digital calipers. The dado kerf was tuned the same way or it won't work.
Ok, I place them all together on my crosscut sled and clamp a stop block to position this stack of spacers EXACTLY on the edge of the kerf to the left of the dado blade so from left to right I have Stop block, 8 1/2" strips, kerf.
Now I clamp 4 box sides together, perfectly flush, jam them HARD against the spacer stack and feed it through the blade. Take out a spacer, jam and cut, repeat till done.
I cut 4 at a time fast, safe, precise and the fit great. This principal could be used for finger joints too. Simple mic the kerf and rip the spacers the exact same width.
Watch ya'll think? I like it. A pic is worth a thousand words:
http://home.swbell.net/snaphook/Pics/boxjoint.jpg
KISS principal. Gotta love it.
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Great Idea. another one of those " Why didn't I think of that.?
. wanna buy a Newly built Lynns Jig?? although I have had failry good Luck with the Small Boxes I built..

joints
planed
jig.
and
I'm
to
and
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In rec.woodworking

Thanks! The simple ones are always like that aren't they?

LOL! Nah, I have one I'm trying to get rid of :)
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In rec.woodworking snipped-for-privacy@nospam.com (Bruce) wrote:

Correction! Rip the strips 2X the width of the kerf, sorry.
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You have rediscovered a technique used by watchmakers for over 150 years.

joints
planed
jig.
and
I'm
to
and
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And published in most basic woodworking texts for at least the last fifty.
I'm really dense, I guess, but where's the "accumulating error?" Each pair is referenced to itself. Set the jig properly and press on.
Router still my preference.
wrote in message

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In rec.woodworking

Makes me look pretty smart then I guess since I didn't read any of those.

If you're indexing pin is off by .005", the width of a dollar bill, by the time you do 10 cuts, you're nearly a 1/16" away from where you should be. My method has no accumulation like that and is self correcting. Any joints cut this way will fit either direction. Flip yours 180 and you'll magnify that 1/16" 2X and will never get it together.

If I had a miter slot near my router, I'd have used it with the same technique, but I don't. I would still bet I'm faster with a table saw than a router though. As long as you have a dado that cuts a flat bottom, I see no reason to use a router.
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Most places regard education more highly than reinvention. Less time, and less "cumulative" errors.
Each pair is independent. As with your method, the pair consists of a space made by the bit - constant- and a reference distance. In your case, removal of the spacer, in the case of tablesaw and router jigs, rereference of the new pair to the original pin.
wrote:

fifty.
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In rec.woodworking

George, are you deliberately trying to be argumentative? I certainly value education but if I'm lost on a dessert island, I'll take the inventive high school dropout with a high IQ over the PhD anyday.

You don't understand cumulative error and I don't care to explain it to you. Go measure a football field with a ruler and a 100' tape and compare the results.
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Or _you_ might consider reading over floundering.
LMAO
wrote:

and
value
high
space
removal
the
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George wrote:

Is that supposed to be like a ship caught on the rocks? If so, it's "founder"; not "flounder (like the fish).
The Spelling Police
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Flounder, as in flop like a fish, just as written.
Compensating errors in the side pairs is beyond his comprehension.
Those who reinvent the wheel spend a lot of time running in circles.

"founder";
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In rec.woodworking

You're a real prick George. I'd bet $1000 right now that I read more in a year than you do in 5 years and I'm not talking dime store novels. In any event, I'm saying a prayer tonite that you and I cross paths one day so I can teach you some manners.
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In rec.woodworking

Like I said, it was too simple to think it was an original idea, but it was for me. What part of watchmaking uses this? Making gears?
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Drilling the mounting plates.
wrote:

was
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