Shop Built Crosscut Sled Size Has Limitations

[Mike Shields]

When I first bought my hybrid TS, I knew I had to replace the miter. I found a great deal on a Jessem Mastr-Slide. The sliding table has been real slick, however, I was always having aggravation in dealing with tear out. Sometimes it seemed I would spend more time trying to find a suitable backing board, then actually cutting.

This has led me to building a crosscut sled. I have runners installed on a BB base that is 24" wide x 18" deep. The blade is centered at 12" to allow L and R cuts. I'm selecting material for the fence, and while doing so, have taken a step back to consider the limitations on the size of the sled.

So, the question:

what size crosscut sled provides the ability to cut the widest range of wood sizes safely?

It looks like the size that I chose might only allow cut lengths of maybe 2 feet on either side of the blade. Not very practical to work with that short size of wood!

Any thoughts?
Mike

[glenn bradley]

Here is a post about a large one (http://www.sawmillcreek.org/showthread.php?t=50581) I made to deal with a project that involved several large panels. I assumed I would cut it down to "normal" after but I just made (http://www.sawmillcreek.org/showthread.php?t=53569&highlight=Sled) a few more (http://www.sawmillcreek.org/attachment.php?attachmentid=66886&d=1182742767) and have kept this one. There have been several occasions that I have been glad I did.

[Joe Scharle]

This is the largest slider I use. 28 X 37 melamine with a single Incra runner. That's a 24 X 42 table top being squared on top of the slider. Needless to say, it works just fine with a single runner. The finger holes are not only for hanging on the wall, but also allow me to apply a pull - push action on the workpiece.
Anything larger goes into my JointAbility.

http://www.ncwoodworker.net/pp/data/194/Fly_Leaf_Table_3_1.JPG

[Mike Henderson]

To cut longer pieces with a crosscut sled - assuming you have a surface on your table saw to support it - you make a jig as follows. Use the same thickness of wood as the bottom of your sled. Put a "hook" on one end, like a bench hook or a shooting board. Make the length of the board as long as you're likely to move the sled.

So now, when you want to cut a long piece with your sled, take out your jig and lay it on the table top (saw table top, that is) to the side of the sled. That jig will not support your work as you push it through the saw.

Mike

[Also, you don't normally make a sled symmetrical. Normally there's more support area on the right (your right as you face the saw) of the blade than on the left - if you're right handed.]

[Brian Penning]

To cut longer pieces with a crosscut sled - assuming you have a surface on your table saw to support it - you make a jig as follows. Use the same thickness of wood as the bottom of your sled. Put a "hook" on one end, like a bench hook or a shooting board. Make the length of the board as long as you're likely to move the sled.

So now, when you want to cut a long piece with your sled, take out your jig and lay it on the table top (saw table top, that is) to the side of the sled. That jig will not support your work as you push it through the saw.

Mike

[Also, you don't normally make a sled symmetrical. Normally there's more support area on the right (your right as you face the saw) of the blade than on the left - if you're right handed.]

Um...OK, I gotta confess that you lost me :o
Got a pic?
Thanks

[Frederick Rowe]

I've got the Jessem Mast-R-Slide on a Unisaw and couldn't be more pleased. If your problem is tear out (and not a matter of needing more area of support for very large cross cuts) then try this trick. Set up your Mast-R-Slide with the stop set on the fence for your correct cut line. Then make the first pass with the saw blade raised only 1/16th, making a scoring cut. Pull back the slide, then raise the blade to the normal height for your particular cut, and finish the cut. I've found as long as I set the fence stop, I'll cut on the same line without any tearout. Remember though, if you have anti kick back pawls, push your cut past the pawls before pulling the piece back for the second cut.

Good luck.

PS-The fence on my Mast-R-Slide was so slick the wood being cut frequently slid during the cut no matter how tightly I held it against the fence. I cut some self adhesive 800 grit sand paper into strips, and installed on the fence face, a huge improvement. With the increased grip of the sandpaper on the fence, I can make the scoring cut without setting the fence stop. Even if you bump your piece after the scoring cut, just shut down the saw, register the scoring slot with the blade, pull the sliding table back, restart saw and make your full cross cut.

[Phil Thien]

So that you don't have to toss what you've already made, I suggest the following.

Finish your sled, and make an auxiliary fence that goes in front of the permanent fence. The aux. fence should be longer, though, and overhang the sides of the sled. Where the aux. fence overhangs the sled, add a cleat on the bottom of the aux. fence that can provide some support for longer workpieces.

Now you have the best of both worlds, a sled that is handy for "normal size" workpieces, and the ability to put an outrigger fence on it for longer pieces.

[Mike Shields]

I've got the Jessem Mast-R-Slide on a Unisaw and couldn't be more pleased. If your problem is tear out (and not a matter of needing more area of support for very large cross cuts) then try this trick. Set up your Mast-R-Slide with the stop set on the fence for your correct cut line. Then make the first pass with the saw blade raised only 1/16th, making a scoring cut. Pull back the slide, then raise the blade to the normal height for your particular cut, and finish the cut. I've found as long as I set the fence stop, I'll cut on the same line without any tearout.

The tearout that I have is not the top or bottom, but at the back of the cut (side supported by the fence). I can't see how not using a backing board or zero clearance fence will prevent that type of tearout.

Am I missing something?

Mike

[Mark Carlson]

Mike,

I had a dubby before the Jessem and I liked how it mounted a block of wood to the end, that was then cutoff, giving you a zero clearance. I did the same thing and then cutoff the end, picture 1. The other way is to mount some MDF to the fence, picture 2. Both methods prevent tearout. I like the 1st method because the block of wood at the end doesn't get in the way of the stop. When I milled the block I milled up about a foot so I can just keep using when needed. The 2nd method has the benefit that you can cut the mdf long and just keep on sliding it to the right when you need a fresh backup for yout cut.

Note: I also use a sled because sometimes I like to have a sled carry the work past the blade.

Another Note: I dont really have tearout issues. I like the zero clearance fence because it tells me exactly where my cut is going to be.

~mark

[Frederick Rowe]

I suppose the only way to eliminate the tear out you describe is with a sled made with a zero clearance slot. Mark's solution looks like it would work.

I work mostly with cherry, white oak, poplar, and maple. I haven't had that kind of tear our at the rear of the piece.

Might it be your blade?

[Joe Scharle]

Mike,
I use one of my sleds for all crosscuts; so ZCI has never been important for me except ripping thin pieces. So whenever I experience tearout it has always been the blade.

[Mike Shields]

Mike,
I use one of my sleds for all crosscuts; so ZCI has never been important for me except ripping thin pieces. So whenever I experience tearout it has always been the blade.

I was ripped! My $100 WW II is NOT good enough!

I just replaced my WW II with a brand new Fusion, and I guess none of you would be surprised to find: no tear out.

I just learned something (hanging my head in shame):

a blade that appears to be sharp, isn't necessarily so.

Thanks!

Mike

[Mike Henderson]

Um...OK, I gotta confess that you lost me :o
Got a pic?
Thanks
I'll post a picture later but the idea is to put a piece of wood alongside the sled for the work to ride on (to support the work).

Let's say you have a sled that has 20 inches from the blade to the side of the sled. If you cut short pieces, even some a bit longer than 20", no problem. But suppose you try to cut a piece fairly long, maybe 48 inches long. The problem is that the work wants to "fall off" the end of the sled - in addition to holding it in place, you have to hold it down. That makes cutting it more dangerous.

But suppose you take a piece of wood that's as thick as the bottom of your sled and stick it under the work, maybe at 30" from the blade. The work is supported and all you have to concentrate on is holding the work against the back of the sled.

Your work can slide over that piece of wood you put under it. Just make sure it doesn't fall off that piece of wood because, if it does, you'll get a surprise as the work rears up on you.

Some people make a "jig" to go with their sled. The jig consists of a piece of wood as thick as the bottom of the sled. It doesn't have to be wide - 4" is plenty - and it should be as long as the travel of your sled.

To make sure it stays in place, you can put a piece of wood on the end of the "jig" that hooks on the edge of your table saw.

Pictures coming soon.

Mike

[Frederick Rowe]

Mike - At least the problem is solved. I would call Forrest Blades and (if your blade is relatively new) see if they'll sharpen it for you. Forrest advertises the WWII as tear out free.

Do try the sandpaper on the Jessem fence. I think you'll find it an improvement.

Good Luck.

[Mike Henderson]

Here's the pictures of the jig I promised to post.

The first picture shows the jig upside down to show the "hook" attached to the end.

The second picture shows the jig in normal position (not upside down) and pushed against the crosscut sled to show that the jig and the bottom of the sled are the same thickness.

The third picture shows the jig in normal operational position. The piece of wood on the sled is just a scrap I found - I didn't have a big piece of wood to use for the picture. In reality, you wouldn't use the jig unless you had a larger (heavier) piece of wood to cut.

The last picture just shows the same thing as the third picture, but from a different angle.

This, combined with my text above, should explain how it works. But if any questions, please post.

Mike