crosscut sled

[Jeff Ziegler]

I have a Ridged table saw. After aligning the blade to the table I am
trying to create a cross cut sled out of 1/2 MDF base and 2/4 Poplar rail
that has been joined and is straight. I am only able to get one side
perfectly square at a time, but I am unable to get both side at 90 at the
same time. Any ideas what I am doing wrong? The only thing I can think of is cutting the sled into half and then set each side at 90 with out being connected.

[Mike Schwing]

I want to help but am not sure I quite understand. I build sleds by first building them whole, then putting the rails into the mitre slots after laying down some washers or dimes to keep them slightly off the bottom of the mitre slots. I then apply double stick tape to the rails, press the sled on top and remove them. Then I screw them on.

I then attach the top rails, with some play in the screw holes for later adjustment. I then run the sled through the moving blade and check for square to the tops. If they're off a bit, I loosen the screws to the top pieces and adjust accordingly, finally gluing it down when I've got it.

What are you doing differently? You should not need to separate the two halves.

I have two sleds I no longer use and would consider selling them - the bottom rails would have to be repositioned...one is a dedicated (and VERY nice) 90 degree, the other cuts perfect 45s... I no longer use them since buying the Jointech Smartmitre.

Whatever you decide - look at the pic below and check out the replaceable guard at the rear of the large one - its awesome! The blade remains inside - no worries about your wrists being sliced. Please consider making one for yourself - its only screwed on so it can be replaced if needed.

http://home.earthlink.net/~schwalden/sleds.JPG

[Eric Apple - Central IN]

How are you measuring square ? One "gotcha" when cutting is if you do not feed stock past both the front and trailing edge of the blade. If you have a heal or lead condition with the blade relative to what is being cut and you don't cut with both the leading and trailing edge, you cut sort of a Vee shape kerf.

This can drive you crazy when trying to do a precise setup.

[Jeff Ziegler]

I am using a carpenters square. I have never seen a 2ft machinist square.

[Eric Apple - Central IN]

I am using a carpenters square. I have never seen a 2ft machinist square.

To clarify, I meant do you make a cut and then try to measure if the cut is square ? Or, are you trying to measure if the blade is square without making a cut ?

[Jeff Ziegler]

After making a cut.

If I get the left side SQ, the right back is long.
If I get the right side SQ, the left front is long

[Eric Apple - Central IN]

After making a cut.

If I get the left side SQ, the right back is long.
If I get the right side SQ, the left front is long


I think I may know your problem. The sled is not traveling exactly parallel to the blade. Meaning the blade isn't well aligned with the miter slots.

Try this, take a board and cross cut it on the sled. Then remove the board from the sled. Put it on a flat surface with the narrow edge on the flat surface. And butt the saw kerf edges together as if trying to make a butt joint. Do not flip the boards positions relative to one another. Just stand them upon the long narrow edges, they should remain in the same orientation to one another that they had sitting on the sled.

Look for light between the joint. If you can't get a perfect joint like this, then your blade is not running parallel to the miter slots.

[Jeff Ziegler]

I have tried to align the blade using a dial indicator and a saw blade. But when I do to tighten the bolts the blade moves. Any ideas? I have also thought about buying a jig to help (http://www.rockler.com/findit.cfm?page=6039). Do you know of another ways of getting it corrected?

Thanks for all the help.

[Eric Apple - Central IN]

Try the cutting test to verify that this is your problem first. If you are patient, you can get the blade aligned and not buying anything additional. Also, mark a blade tooth and rotate the blade to use the same tooth as you move and check the dial indicatior. Don't use a different tooth to check your measurements.

The PALS system has bolts that can replace the existing bolts for about $22. You then can miroadjust the PALS "brackets" and alignment is much easier. Check this link: http://www3.woodcraft.com/Marking&Measuring/woodworking/895.htm

You would need to call the vendor to check on availability for Rigid.

I usually just work thru the frustation and don't buy the extra parts. But, they would really help.

[David LaRue]

Squaring a crosscut Sled (http://www.taunton.com/finewoodworking/pages/wvt002.asp)


The link above makes it real easy to square your sled... :)

A couple of more sled links:

Another link to sleds (my site, full disclosure) (http://home.comcast.net/~mywoodshop/html/cross_cut_sled.html)

Dave

[Ken Salisbury]

Welcome to The Creek. I am sure you will get the necessary help with your problem.

Please read the Saw Mill Creek Terms of Service. (http://www.sawmillcreek.org/terms.php ) You will note that a first and last name are a requirement to be a member of SMC. Please let me know what your first and last names are so I can have your registration updated accordingly. You can respond with that information here or you can e-mail me. (ken@kenswoodcentral.com)

Thanks in advance.

[Jim Becker]

I am using a carpenters square. I have never seen a 2ft machinist square.
\
Have you checked to see if your "carpenters square" is actually square? Many are "not square" for the purposes of fine woodworking and machine setup. Place it on a piece of wood and draw a line perpendicular to the edge. Flip the square over and draw another line starting at the same point. The lines MUST be on top of each other. If not, your square...isn't.

IMHO, everyone should invest a few shekels on a high quality square for machine setup; either something like a Starrett combo (also check for square) or a small engineer's square. You'll be glad you did. Many times the stuff at the local hardware store or the big-box just isn't up to snuff for this important task. And heck...it won't hurt your woodworking, either!