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Ken Miller
01-11-2015, 2:32 PM
What am I doing wrong? a simple cutting board made up of glued up strips. after gluing I ran the length of one side along the jointer and followed that by ripping the opposite length for parallel. Than I cross-cut each of the sides using a cut-off sled and i get corners out of square. Is this my machines out of square. I checked the cut-off sled to the blade and its square. I check the fence to the blade and its square. If I get one square corner is there a correct sequence of cuts I could make to assure the other three corners are square? thanks in advance

George Bokros
01-11-2015, 2:43 PM
Is your cutting board slipping on your sled? I had a problem with my Incra miter gauge not giving me square cuts and I found the piece was slipping on me when I cut it. I added a sub fence with sandpaper facing and the problem was corrected, my stock does not slip on my fence when I cross cut any longer. Cheap fix to a problem that had been haunting me for some time.

Mike Cutler
01-11-2015, 2:44 PM
Ken

My guess is that your rip is not a parallel as it need be. You're cutting square to each corner, but the corners appear to not be square to each other.
One other thing is how long is your reference square? It actually takes a bit of tweaking to get "biggish" panels square. It doesn't take much to be off. Something a small square may not indicate.
I have a JessEm slider on my table saw, and it takes a bit of tweaking, and shim stock, to get that to crosscut square, throughout it's travel.

Jerry Miner
01-11-2015, 2:54 PM
I checked the cut-off sled to the blade and its square.

The important check here is square to direction of travel (i.e. the miter gauge slot, assuming that is what guides your sled), not so much square to blade.

Square to blade affects binding, square to travel affects squareness of cut.

Are you familiar with the 5-cut method of checking your sled? I would run a check.

Ken Miller
01-11-2015, 3:04 PM
I thought I held it very tight but I guess it could have slipped. I'll give it a try, thanks

Ken Miller
01-11-2015, 3:07 PM
I checked the sled with a machinist square, maybe 6 inches, I gave a quick check to the fence but maybe I need to recheck, thanks

Ken Miller
01-11-2015, 3:08 PM
Never heard of the 5-cut method of checking a sled, care to share?

Jerry Miner
01-11-2015, 3:21 PM
Here's one of the many on-line explanations (you can also find youtube videos by searching "5 cut method" or "check a sled" etc.)

http://www.newwoodworker.com/basic/5cut.html

Basically, you cut a largish panel--whatever your sled can accommodate-- rotating for each cut so that the just-cut edge gets registered against the fence. After 5 cuts, you check the last cut-off for parallel (Ideally, it's perfect, but if not, it shows 5-times the fence angle error).

If you don't have calipers or something, you can check the diagonals of the final "square panel"---but using calipers is more precise.

Ken Miller
01-11-2015, 3:28 PM
Thank you for taking the time and even including a link, i appreciate it. It will watch, try it out and hopefully find the answer to what is wrong, but right now I need to relax and watch some football. enjoy your day

Art Mann
01-11-2015, 5:47 PM
The 5 cut method is about the best possible way to verify squareness of a sled. It is superior to using a square because it doesn't depend on the accuracy of your reference square. You can get digital calipers from a super discount place for around $10 and they will be more than accurate enough for your purposes. You can tweak the accuracy down to a few thousandths of an inch over a few feet.

Al Launier
01-11-2015, 6:06 PM
Ditto the 5-cut method. Also, I prefer a touch of play between the runner & miter slot. This allows me to push the sled to the blade side during the cut & to pull it away when pulling the sled back.

Kevin Jenness
01-11-2015, 11:25 PM
Another way to check the square setting of your crosscut fence that does not require any precision tools:

Rip a panel as wide as your crosscut sled will handle with a truly straight edge and a bit longer than your sled. Put the straight edge against the crosscut fence and make sure the fence is straight. Crosscut the right end, then crosscut at the panel's midpoint. Flip the righthand piece over, keeping the straight edge against the fence and butt the cut ends together. There should be no gap between them. Any gap will show twice the angular error in the fence position.

Matt Day
01-11-2015, 11:41 PM
Make sure your blade is at exactly 90* too. If it's off a little, that can throw things out of whack.

+1 to the 5 cut method. Google "Woodwhisperer table saw sled" to find a video where he explains and uses the 5 cut method - another example for you.

Jim Rimmer
01-12-2015, 1:14 PM
Make sure your blade is at exactly 90* too. If it's off a little, that can throw things out of whack.

+1 to the 5 cut method. Google "Woodwhisperer table saw sled" to find a video where he explains and uses the 5 cut method - another example for you.

When I first read your OP the 5 cut method was the first thing in my mind. Try it - low cost and could solve problem or eliminate a potential source.

Mike Schuch
01-12-2015, 1:23 PM
It sounds to me like your blade is not parallel to your miter slot.

Pat Barry
01-12-2015, 1:28 PM
What am I doing wrong? a simple cutting board made up of glued up strips. after gluing I ran the length of one side along the jointer and followed that by ripping the opposite length for parallel. Than I cross-cut each of the sides using a cut-off sled and i get corners out of square. Is this my machines out of square. I checked the cut-off sled to the blade and its square. I check the fence to the blade and its square. If I get one square corner is there a correct sequence of cuts I could make to assure the other three corners are square? thanks in advance
I assume you are concerned with the various strips fitting together end to end to make a tight glue joint. If its the overall cutting board I wouldn't even worry about it unless its so far off the board looks like a parallelogram rather than a rectangle. If its the strip fitting then just tweak / shim your crosscut sled fence until two cuts match correctly. That shouldn't take much precision for small parts. If its big pieces, then something like the 5 step method is your best bet to verify