Jun 8, 2009

Building a cut-off sled/box

How to build an accurate, smooth functioning, cut-off box.




What's it for?

A cut-off box is good for many functions on the table saw. This sled will make your repetitive work seem less monotonous, while producing a quality cut the can be reproduced over and over again. While a cut-off box is designed for cross cuts, It also can produce tight mitres along with great looking joints. After all a table saw is our "go to" tool when it comes to accurate, repetitive cuts. I'll cover different jigs that can be applied to the sled in future updates.

What materials do I need?

  • A table saw (Not portable)
  • A piece of good 3/4" plywood (Not shop ply, cabinet grade is good).
  • A 2" x 3" x 8' ( +\-) straight hardwood. (preferably oak or maple, dried)
  • 2 strips of hardwood 3/8" x 3/4" x depth of sled. (Width may vary on different saws)
  • Some screws (#8 x 1 1/2" and 1" should be good)
  • a pneumatic nailer with 1 1/4" and 1" nails
  • 2 Pennies

Where do I start?

Step 1:

Find the width of your table saw and decide on how wide to build your box. Cut the front and back supports from the solid 2" x 3" wood. You may need to glue up a piece where the blade will come through, that's why I made this step 1. Get creative and make a nice fence for the user side, but make sure you are able to grip your work piece. In other words only have it rise near the blade. See photos

Step 2:

Start by cutting your pieces of plywood to the dimensions of your table saw. I like to leave an inch reveal on the sides and the same front to back. This is personal preference, and you should build according to your needs. Remember the bigger it is, the heavier it is.

Step 3:

Place two pennies in each slot on the table saw to support the strip of hardwood. this will hold them up high enough to allow a nail to hold the parts firmly against the bottom of the sled. Lay the strips on top of the pennies. Next, lay the plywood on top of that squaring it up to the user side of the saw. Once in place layout where your rails end up and mark a line with the framing square across the top of the sled for reference.

You can now remove the plywood and apply yellow glue to the runners in the slots, you may leave them in place. Once you have the glue and nailer ready, lay the plywood back on top and realign all your marks, then square it up again to the user side. Apply pressure to the work piece and work your way from front to back putting a nail every 6" or so. Do this to to the other guide and remove your sled. You'll need to clean out any glue that squeezed out with a wet rag. Flip the sled over and pre drill and countersink 1" screws to permanently attach the runners. Don't forget to remove the pennies.

Step 4:

While the sled is still upside down. You can go ahead and attach the back side of the sled to the plywood. Screws and glue for this side will ensure a solid, rigid, long lasting sled.

Pre drill everything you'll use a screw in.

Step 5:

Slide the sled back and forth on the saw with the blade lowered. You might need to sand or plane some spots on the runners to ensure a smooth sliding product. Wax the runners and underside with paste wax, pledge, or other dry lubricant when finished.

Step 6:

Now you can attach the front side. Only attach with one screw at first, left or right, not center.(this will be adjusted in the next steps). Do not use glue on this side, if the fence needs adjusting in the future, it can be easily re-squared.

Step 7:

With the sled in place on the saw in it's "home position" and the blade completely lowered, start the saw. Holding you work piece in place with one hand while raising the blade slowly with the other, cut through the plywood (watch your hand placement). Once you just get through the plywood push the sled into the blade almost reaching the front fence, but not cutting it. Then pull the sled towards you and cut almost to the backside but not through. Be careful here as the sled will want to kick.

Step 8:

Use a clamp to apply pressure to the fence. Snug it up, but still allowing you to move the board with a tap. Place the framing square against the fence and line it up with the cut you just made. One squared, lock it down with the clamp, flip it over, and finish screwing it all the way across.

Final Step:

Once the sled is squared up make sure by cutting a sample piece. Using a different square, compare the cut and adjust if needed. You might want to make a stop block with a notch in it to use exclusively with your new sled. Enjoy, and check back for updates on jigs and other uses for your sliding cut-off box.

Tips:

  1. Mark out some basic measurements for quick reference.
  2. Try to use a blade of the same thickness always. (keeps your cuts clean and accurate)
  3. Store the sled somewhere convenient.
  4. Don't store it on the fence side (back side down)
  5. Angle cuts should be kept to a minimum.(tilted blade)

Author:

Frankie Talarico Jr.

www.getneds.com

Bulk wood shop supplies.

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