Crooked Crosscuts

[Trapezoid]

I recently purchased a new Mark 7. I've been through all the alignment processes and everything appears to be fine. But every time I make a crosscut, it is wider at one end than it is at the other. I just tried to cut a piece of plywood. It was 12 inches wide and 10" long. I tried to cut it down to 8 3/8". After the cut, one end was 8 3/8" and the other end was 8 5/16". It seems to be consistently off by abot 1/16". I've tried everything I can think of to no avail. I'm using the miter bar and not a crosscut sled. Any suggestions will be greatly appreciated.

[jsburger]

I recently purchased a new Mark 7. I've been through all the alignment processes and everything appears to be fine. But every time I make a crosscut, it is wider at one end than it is at the other. I just tried to cut a piece of plywood. It was 12 inches wide and 10" long. I tried to cut it down to 8 3/8". After the cut, one end was 8 3/8" and the other end was 8 5/16". It seems to be consistently off by abot 1/16". I've tried everything I can think of to no avail. I'm using the miter bar and not a crosscut sled. Any suggestions will be greatly appreciated.

Assuming your table (miter slot) is square with the blade have you checked the miter gauge being square with the blade. The 90* stop on the miter gauge is adjustable to make it square.

[ERLover]

Have you with a square, set it against the blade and not touching any teeth, then no matter what the miter gauge ses set it square to the squares other edge? Then try a cut.

[dusty]

When you make the cut, note which edge measures 8 3/8" and which edge measures 8 5/16".

Move the miter gauge to the other side of the blade and make the same cut. I expect that the long edge is now the short edge! If so, the miter gauge is NOT SQUARE to the miter track.

That error across a 10" board equates to only .4°error. When you square the miter gauge, you have to be a bit picky.

If the problem persists, loosen the locking knob on the miter gauge, take it out of the miter slot and turn it upside down, put it back in the miter slot and push it up against the front rail, hold it there tightly and re-secure the locking knob. After doing this, I believe you will find the miter gauge to be square with the miter track.

Once you have tracked this down, I would suggest that you think seriously about purchasing a "Miterset".

http://miterset.myshopify.com/

[algale]

Check carriage lock, headstock lock and quill lock.

Also, make sure that you are not allowing the work piece to creep into the blade.

[charlese]

algale nailed my thought. This issue is probably something really simple to fix. Failure to lock the carriage of the headstock will cause this type of issue. Don't ask me how I know .

[JPG]

I realize I am repeating much of what has already been posted here, but the whole picture and sequence are important to success.

First be aware that ALL locks MUST be secure when adjusting/checking alignment or actual cutting.

Verify/adjust the table miter gauge slots to be absolutely parallel to the face of the blade(or sanding disk). Actually this is a quill shaft perpendicular to the slot check.

Verify the miter gauge 90° setting and stop. Again the word is absolutely(or as close as you can get it).

Last but not least, use the 'safety grip' so as to prevent the workpiece from drifting across the face of the gauge(which will directly cause the problem.


Now a question. Are you trying to make a 90° cut, or a cut parallel to the other end(cutting to length). If the latter, the rip fence is a more reliable way to do this assuming workpiece size allows that.

Also if the 'far' end is not square, cutting it square will always give you the 'problem'.

[john_001]

This may be a long shot, but are you sure the square you used for your set up is really square? I had three inexpensive squares and all of them were off to some degree - it drove me nuts until I discovered it.

[oldiron]

As John 001 stated, Are you sure your square which was used to square the miter to the blade is square? It could possibly be creep however, It's usually a miter out of square.

When you square the miter slot to the blade, Have you flipped the square over and checked the back side of the miter slot to the blade? If it squares flush to the blade than it's not your miter.

Mike

[wa2crk]

I had a similar problem this week. I had been using my belt sander to square some pen blanks.When I used the miter gauge on the table saw I noticed that the cut line drifted slightly. Problem: The miter gauge was square to the platen on the belt sander but it was not square to the table saw blade. The worktable of the belt sander can be easily cocked a little off square and moving the miter gauge to the saw table will reveal a problem. Easy fix is to make sure that all things are square when you move attachments to a different SPT.
Bill V