Crosscut Sled Thickness

[Glen Blanchard]

I am curious if there is a "standard" thickness for crosscut sleds (the sled itself). For what size sled is 1/2" plywood sufficient or is 3/4" material always used regardless of size? I will be building a couple new sleds (one for small, detailed work and one for larger panels) and am thinking it through.

[Jerome Hanby]

I used 3/4" but it was more a function of what I had on hand than a design consideration. I've seen a lot of write-ups on crosscut sled builds where 1/2" sheet goods were used. As long as it's flat, the saw's table should provide lots of support and the weight would be less.

[Prashun Patel]

Surprisingly, nobody but me seems to do this:

I use 1/4" hardboard. It's light, stable, and minimizes the height the blade has to travel thus increasing the max height of the stock you can cut.
The leading and trailing edges are 2" hardwood and the runners are oak.

Light and stable.

A while back, I made a sled with a hinged lid out of lexan. Helps with dust control.

[Jamie Buxton]

Like Shawn, I use 1/4". This maximizes the cutting capacity of the rig. I use 1/4" Appleply rather than hardboard. It is a little stiffer, so the rig flexes less when I pull most of it off the table at the beginning of a cut.

[Heather Thompson]

Surprisingly, nobody but me seems to do this:

I use 1/4" hardboard. It's light, stable, and minimizes the height the blade has to travel thus increasing the max height of the stock you can cut.
The leading and trailing edges are 2" hardwood and the runners are oak.

Light and stable.

A while back, I made a sled with a hinged lid out of lexan. Helps with dust control.

Plus 1 on what Shawn said, also hardboard is very cheap so you can make many sleds. When the kerf is getting nasty it is no big deal to remove the leading/trailing edges and reuse them on a new one.

Heather

[Gary McKown]

+2 on thin material, except if you want to fashion hold-downs, use replaceable inserts, etc. - I don't think anything like these would work well with thin hardboard. As a compromise, I used ½" (12 mm) BB ply for my large sled with adjustable Incra runners, and ½" MDF for a smaller single-runner version. I think 9 mm ply might be an even better choice.

[Prashun Patel]

You can make removable inserts by ripping the deck a few inches on each side of the blade and then attaching that "ZCI" to the front and back rails.

As for hold downs, my last sled had toggle clamps attached to the front rail. But on my latest, I didn't bother. My front rail is lined with sandpaper, and it does a fine job of holding wide stock in place. If I really need some muscle, I just use a low tech bar clamp.

[Scott Hildenbrand]

Surprisingly, nobody but me seems to do this:

I use 1/4" hardboard.


I used Pergo laminate flooring.. Nice plastic coating.. Slides like ice.. Just glued and snapped some boards together and then cut to size.

NOT like you need flex resistance in the base material. Only thing that needs to stay put is the fence.

[Harold Burrell]

I use paper. Just standard notebook paper scotch taped together. VERY light and economical. Whenever I need to replace it, I simply tear it off and start over.

I also find that the lines in the paper make lining everything up a snap.

It also comes in very handy for jotting down notes and measurements, etc.




(OK...none of that is true. I just so badly wanted to be able to contribute to this discussion. Sorry.)

:o

[Glen Blanchard]

I am planning on having a replaceable zero clearance insert which will be held in place by a few screws. Will 1/2" material be sufficiently thick after I cut the dado for the insert (I suppose about 3/16" thick) to hold a screw?

[Scott Hildenbrand]

(OK...none of that is true. I just so badly wanted to be able to contribute to this discussion. Sorry.)

:o


ROFLOL.... Ok.. That was funny... ;)

[Russ Kay]

You can always screw into the thicker stock at the front and back of the sled.

[Ken Shoemaker]

+1 for Harold .... However, I also use PostIt notes for the front and back fence for the rigidity..... MOTHER OF GOD!!! See what you started..:eek:

[Phil Koundakjian]

This posting came at the right time. Would it be possible for an uninitiated to cross cut sleds be shown how the ZCI is installed? .. pictures would be great. Thanks .. Phil

[Gary McKown]

Phil - although Mark hasn't been around for a while, here is one from the Master at crosscut sleds:

http://www.sawmillcreek.org/showthread.php?t=48899

Essentially the ZCI is a replaceable strip dadoed in along the cutting line. Often the dado straddled the blade, with a different kerf for each blade setup. Note that Mark's design just has a single insert on the outboard side of the blade (see the last two pics), using different widths for the strip (the first cut on a "fresh" strip establishes this width). On most of Mark's designs, the strip was fastened only to the bottom of the front and rear fences (he had some clever way of fastening them, but I don't recall the exact details). I think it was a dowel that extended down through the fences and into holes in the insert (walnut knobs in last two pics).

And as to the original topic, I think you can see the necessity for a thicker bed in such an "advanced" design.

Hope this helps.