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This crosscut sled is super accurate. I made it a while back and have been using it for a couple years now. It has two T-track slots, one on either side of the blade to hold down the pieces. There are two handles on the back which help to keep hands away from the blade. The rear block is super thick to help cover the blade as it exits the workpiece.

The second picture shows the extendable stop block which allows me to cut pieces which are longer than my sled is wide. The threaded rod and angle iron nest inside the fence and lock in place with a thumbwheel.

The fence attaches to the sled with two bolts and can be further secured with screws. On the right side of the fence is the fine adjustment mechanism which is of my own design. The third picture is a close up of the mechanism. I tried making a sketchup drawing of how it works, but I couldn't put it together. The octagon shaped wheel has two threaded inserts, on one side is a 1/4"-20 insert and the other side has a 5/16"-18 insert.

As the wheel is turned, it pulls in the one side and pushes out the other side. Because the movement between the two sides is unequal, for every 18 revolutions of the wheel, the fence moves 1/10". For those of you doing the math, one revolution is 5 thousands of an inch.

I used the fine adjustment wheel to dial in the fence, then secured the bolts to lock it in.

Gallery

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Nice sled. That fine-adjustment wheel is a brilliant idea. I'll have to use that sometime.
 

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Thanks AdrianT. I'm afraid i didn't do a very good job of explaining how the mechanism works. I plan to do a blog detailing its construction when I make my box joint jig. I hope to do it within the next two weeks.
 

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Remarkable! I LIKE! I've been wondering about how I am going to built a really accurate sled and you've just given me some really good ideas, suggestions, hints, etc. This is on my "next 5" list for sure. Thanks. I CAN DO THIS NOW!
 

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Sweeeeet !!!!!
 

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Dave, really great idea on the adjuster. If I may be sold bold … the 5/16-18 rod gives a movment of 0.055 inches per single revolution. The 1/4-20 rod gives a movement of 0.050 inches per single revolution. Since one is pushing (unscrewing) and one is pulling (screwing), the difference 0.055 minus 0.050 or 0.005 inches, is the movement of the fence for one revolution of the adjuster wheel. ... very accurate adjustments for truly fine tuning the fence. Thanks for sharing this as many of us will put it to good use.
 

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2,217 Posts
This is one of the best crosscut sleds I've seen. Fantastic job… I might be stealing this soon.
 

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Thanks everyone. I thought long and hard about how to make my own micro-adjuster. The two different pitched threaded rods provided the perfect solution. The hardest part was figuring out how to join the two different parts. I first tried to turn and thread a rod, but had trouble getting the two halves concentric. I decided that the threaded inserts would be the next best thing. As an added bonus, it provided a thumb wheel for tool-free adjustments.
 

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Would like to see photos of this in use, on your table saw. Hope you'll add some photos.
 

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Unique design and well done.
 

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Nice sled. Very original adjustment. I like the extension to the width of the sled.
Sorry for being dense, but other than the original sled setting, what do you use the adjustment for?
 

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Ralph: after the initial setup, the adjustment isn't used anymore unless the jig becomes misaligned. If I had made the jig so the adjustment wheel could be easily removed, it could be reused on other jigs.
 

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First, awesome design! Second, I have the same question as Ralph…. did you leave the adjuster on for future recalibration? Is your top hardboard on top of ply or mdf? I love the handles, very smart and easy way to keep the hands out of harms way.
 

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I just had a flash of inspiration/understanding, and I know how the adjust mechanism works! Sort of like a turnbuckle, but instead of both in or both out, it's one in/one out, at different rates, am I right?

Seems super simple to build, too - one through hole and 2 inserts?
 

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Too bad you can't use it elsewhere. I wonder if a universal adjustment can be made with that mechanism.
 

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Love the idea. I'm sure we will be seeing these pop up for different applications. I have only one suggestion that would take this over the top… Pentagon adjustment knob. One flat = one thou!

Well done!
 

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JJ, you got it. Kinda like a turnbuckle, only different. I used a piece of 8/4 scrap cherry, drilled one through hole so the two inserts would be concentric, then put the threaded rod In and added a dab of locktite to hold them in place.

The sled itself is hardboard over plywood. I made it so I could easily replace the hardboard in between the hold down tracks if the kerf ever got too big.

The plan was to add a removable plexiglas guard over the saw blade but I never got around to it.

If I unscrewed the one half of the bracket attached to the adjustment wheel, I could back out the threaded rod from the other side and recover the wheel for use in other jigs. I didn't plan for this because i expected to have more micro-adjustment mechanisms made. My original plan was to have a friend machine a dozen or so threaded rods with the different thread pitches. He moved away before I could get him to make them for me. I believe any machinist with a lathe could produce a few of these in a short time.
 

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Do you have something special done when you have the rods machined? All-thread is as common as dirt.
 

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Great sled, wonderful idea to set up the fence
 

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Excellent, I would await a detailed blog on this. Fine tune is a brilliant design with different thread bolts.
 

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If anyone is still following this thread, I have posted a video explaining how the micro-adjustment mechanism works. Its under my blog, and videos.
 
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