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Gordy Anderson
07-23-2008, 11:13 PM
What's the right way to use a sled? I'm gonna build my first one but I'd like to know how to use it first. What keeps it and the piece you're cutting from kicking back? Do you cut, then stop and turn off the saw or can you pull it back while the saw is still running?

Had my first kickback tonight:eek:. That sure is an attention grabber. No injury but I'm a little overly cautious right now.

Thanks, Gordy

Mike Henderson
07-23-2008, 11:22 PM
If you're using a stop block, the best thing to do is to leave the sled forward and turn off the saw. But if you're not using a stop block, you can pull the two pieces away from the blade and move the sled back to the starting location.

Note that you should have a piece on the sled for the blade to remain buried in when the sled is forward. You do not want the blade exposed when the sled is forward.

That said, I often pull the sled back without moving the piece away from the blade (but without a stop block) and have never had a problem. I do have my hand on the piece when I pull the sled back, however.

A sled is a real necessity with a table saw.

Mike

Chuck Tringo
07-23-2008, 11:24 PM
Do you have a picture of your crosscut sled ? A properly built one should not have much chance for kick back at all. If you have one with 2 sliders that straddles both sides of the blade there is a rear backer to support both the cut piece and the offcut. If you use a sled that is only on one side of the blade, there could be a slight chance but a few small safety measures would prevent any chance.....

1. First off, Never EVER use your rip fence while crosscutting

2. Second, for long cut offs, make a drop off platform on the other side of the blade that is the same thickness as the crosscut sled to catch the cutoff.

3. Don't stand behind the blade, Stand behind your sled.

Jesse Cloud
07-23-2008, 11:42 PM
I agree with the advice above - kickback is very unlikely using a crosscut sled.

As for the advisibility of pulling your sled back while the blade is running... Mike is right, if you use a stop block the piece is trapped between your block and the blade and a very slight movement can send the piece to Mars.

An alternative to turning the saw off is to lower the blade, pull the sled back, then raise the blade.

If you don't understand why you got kickback, ask us. There's usually a good reason that would be easy to avoid in the future.;)

Denny Rice
07-24-2008, 12:04 AM
Gordy,

Yea, what Chuck said.......... LOL

Chuck Tringo
07-24-2008, 12:06 AM
I should probably add a number 4.... clamp or hold the workpiece firmly until it is clear of the blade; especially with a stop block as Jesse mentions.

mreza Salav
07-24-2008, 12:44 AM
You've got some good advice here.
A cross-cut sled is a very very helpful jig for a table saw. I have two, one big one (seen below) that can cross-cut up to 24" wide boards, and a smaller one for smaller pieces.
Both have T-tracks with hold downs. You can also see the splitter in the back of the blade and the piece Mike was referring to to hide the blade (when the sled is pushed all the way).
Note that by adjusting the dado cuts in the outfeed table in which the runners will go, you should make sure that the sled stops at a point such that the blade does not come out of this piece. BTW, the over-the-blade guard is also home-made.
93120

John Keeton
07-24-2008, 7:55 AM
Had my first kickback tonight:eek:. That sure is an attention grabber. No injury but I'm a little overly cautious right now. Gordy
Gordy, consider yourself lucky on your first kickback! My first one is still a vivid memory of 23 years ago. I had to go out in the back yard and pick up the piece - after it went THROUGH the wall of my shop, THROUGH the vinyl siding, and about 30' into the yard. That was an "attention grabber." Needless to say, I shut down the saw, went in the house, and didn't touch my shop door for awhile. Had to rethink that one several times to get back my courage. In retrospect, I made at least three critical errors - very good learning experience that could have been a disaster.

I don't use a sled, but can't remember my last kickback. I am VERY cautious, but a sled is obviously the way to go. Been watching with interest the threads on sleds. Some great ideas to combine into one that will mesh with what I do.

Prashun Patel
07-24-2008, 8:58 AM
On repeated cuts, I like to lower the blade through the piece and through the sled between cuts. Then you can safely slide the sled back to the start position. This avoids having to wait for the blade to spin down between cuts.

Kevin Davis
07-24-2008, 11:19 AM
Kreg makes a nice flip stop that I used when making my sled. You can just flip it up, slide your wood over and pull the sled back. The stop doesn't move so you can repeat the same cut. Product Model #KMS7801, $29. Here is a picture.

file:///C:/Users/Kevin/AppData/Local/Temp/moz-screenshot-1.jpg

Jim Cunningham
07-24-2008, 11:36 AM
Depends on whether you are using a stop block or not. If not, I move each piece away from the blade CAREFULLY! and then move the sled

Cliff Rohrabacher
07-24-2008, 12:15 PM
From my old days of using sleds and such:
Just slap the lumber in the sled and shove it through the blade.

Kick backs while using a sled~?? Hmmm

There are only a few things that can cause a kick back:
1.) binding of the stock against the blade
.........(i) wood stress release causes pinching on the aft of the cut.
.........(ii) Guide slots not parallel to the blade causes binding of stock against blade
.........(iii) rip fence improperly set so that it causes stock to bind against the blade.

2.) stock riding up the blade off the table then being slammed back when a tooth catches. Stock riding up thye blade during a pass can be caused by:
.....(i) really dull blade not cutting
.....(ii) feed rate too fast
.....(iii) inadequate down pressure on stock while cutting.


I'm guessing your problem was either #1(iii) or #2(ii) or both.

As an aside:
If your lumber moved at some point during the cut so that it pinched the blade that'd cause a kick back, it's really unlikely unless you start and stop the cut with enough force to cause the lumber to shift forward on the sled (READ: out of controll herky jerkyness). I just don't imagine you did that. Does the sled slide smoothly? If not, make it do so. Start with wax. If that fails look for binding and use a plane or abrasive to reduce high spots.

so it's either that or your blade height was such that the stock rode up on the blade and a tooth caught and slammed it down and back or the slots are out of tune (out of tune = not parallel). Those are the only possibilities for a kick back while using a good sled on a tuned saw.



When I made sleds I didn't fasten the guides to it until I was done with everything else.

Then I'd lay the guide rails in the slots on the saw with just a touch of glue on 'em.

Pre-drive some brads in the sled body where the guide rails will go.

Then, set the new sled onto the guide rails and set the brads before drilling for the screws to finish.

That way I let the guide slots dictate the location of the guide rails and eliminated the need for super precise location.

glenn bradley
07-24-2008, 12:42 PM
I do what Mike H. said.

Gordy Anderson
07-24-2008, 3:52 PM
Not sure where I mis-spoke, but I don't have a sled, I'm getting ready to make one.

The kickback was my own fault. I was standing to the right. I cut a board, turned off the switch, then reached to slide the scrap piece (on the left) away from the blade. I assume I moved it at an angle and some part of it caught the slowing down blade. The guard was in place and it was on the opposite side so it never got close to me. and since I was sliding it, it just slipped it right out from under my finners.

It makes sense with the sled in the runners it can't twist or slide laterally, and with the wood against the back it shouldn't twist either. I think that's the theory I was looking for to convince me it's safer and more accurate than using the miter.

Thanks for all the responses...

Gordy

Prashun Patel
07-24-2008, 4:30 PM
It's not necessarily more accurate than the miter (when yr piece is properly clamped to the miter fence). It's only safer because it can fully support wider stock, which would hang off the front of the table with a miter and would prevent the miter bar from engaging the slot.

Leo Zick
07-24-2008, 10:23 PM
why do you need a sled? cant you just use the fence?