Table Saw Cutting Funny

[davebodner]

Maybe this question will help diagnosis: Which way is the cut curving? Convex to the left or to the right? Does it happen consistently? Does the same thing happen on a crosscut?

Put a straightedge on your saw blade and on your fence.

Finally, wood will move. Cutting it can release stresses, so your cuts end up not straight. In this case, the width of each piece should be consistent even if the pieces are curved. If the cuts themselves are curved, then the width of your pieces should vary. Check the width of the curved pieces all along the length.

[jsburger]

Well guys I can honestly say I definitely did not get a kick back but I cannot definitely say the wood did not move on me. It has in the past... I have had it close the saw kerf and pinch my riving knife and all sorts of issues in the past cutting this batch of walnut. So I can't rule it out but... I ripped a 5.25" by 34" board at 2.5". That first piece is straight as an arrow. The second piece I ripped had the arc to it. Why would one move and not the other? I had 3 boards that were 34" and all three of them did the same thing on the second cut. I could try cutting some other kind of wood to see if I have the same issue. That would be easy enough. If I can get the rain to let off long enough to the get saw out today I'll give that a try.

That being the case I suspect you are seeing the same thing again.

[KCollins]

Russ,

ON THE FIRST PICTURE WITH ALL 6 BOARDS IN IT. One end with all the boards flush is 15.5"strong wide. The other end with the gaps is 16" on the money.
THE TWO BOARDS TO THE RIGHT OF THE 4 THAT ARE FLUSH TO ONE ANOTHER. Measure 1/16" narrower at the gap end than at the flush end.
IF YOU MEASURE THE REMAINING 4 THAT ARE FLUSH. They are exactly 10.5" wide on both ends.

Hope this helps clarify.

[KCollins]

Plywood isn't a bad idea.

[RFGuy]

Kevin,

I am no longer active on the forum, but I believe your post and the responses you received illustrates a point I failed to get across to other members of this forum in the past so I will interject here on this thread in one final attempt. IF this isn't your problem, I apologize for the following...Can you explain how you jointed the boards? What jointer was used, was it the Shopsmith 4" jointer? At the link below I discuss challenges with the Shopsmith 4" jointer, but I encourage you to watch the video shown there as it shows what I will explain next. What you describe and the pictures you show suggest the boards were not jointed fully IMHO and/or were jointed on a jointer with too short of a bed length. Step 1 with new lumber is to face joint the board to get one flat reference surface. This is problematic on the Shopsmith jointer because it is only 4" wide and also the bed length is too short (which means any curvature of the board will not be taken out). Step 2, once you have one flat face is to joint an edge making it exactly square to that flat face surface you referenced. Step 3 is to plane the opposite face side making it parallel to the other flat face from the jointer, but also reducing board thickness to final thickness dimension. Step 4 is to use the jointed edge as a reference against the tablesaw fence to rip the other edge parallel to it and reaching final width dimension. This process is the ONLY way to ensure a woodworker can take raw lumber or even surfaced lumber that is irregular from the big box store/lumberyard and make it perfectly square, straight and parallel on all sides. Yes, you will see YT videos of people suggesting other methods as a substitute to jointing for the shop that doesn't have a jointer. I have even seen people try to suggest they can joint on a tablesaw which isn't true. IF your lumber is fairly straight to begin with, has not internal stress when cut and isn't twisted, then a woodworker can often get by with just a tablesaw and achieve acceptable results most of the time. When your lumber is more natural and hasn't already been pre-milled for you, you MUST follow the steps I describe above to get acceptable results. I hope this helps.

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[larryhrockisland]

It might be interesting to see the boards in the first picture paired back as they were when you ripped them. They look like you moved them around,flipping faces or swapping ends looking for best fit and grain patterns (certainly nothing wrong with that) but I would say some of those would not even fit back together to themselves cut to cut just because of the stress being released.

[JPG]

I suggest thee stop chasing thy tail be comparing edges of different boards.

You need a known straight reference(straight edge or table surface) to critique each board edge.

[br549]

Is a feather board (or equivalent) being used to keep the stock pressed tight against the fence ahead of the cut?

[KCollins]

Kevin,

I am no longer active on the forum, but I believe your post and the responses you received illustrates a point I failed to get across to other members of this forum in the past so I will interject here on this thread in one final attempt. IF this isn't your problem, I apologize for the following...Can you explain how you jointed the boards? What jointer was used, was it the Shopsmith 4" jointer? At the link below I discuss challenges with the Shopsmith 4" jointer, but I encourage you to watch the video shown there as it shows what I will explain next. What you describe and the pictures you show suggest the boards were not jointed fully IMHO and/or were jointed on a jointer with too short of a bed length. Step 1 with new lumber is to face joint the board to get one flat reference surface. This is problematic on the Shopsmith jointer because it is only 4" wide and also the bed length is too short (which means any curvature of the board will not be taken out). Step 2, once you have one flat face is to joint an edge making it exactly square to that flat face surface you referenced. Step 3 is to plane the opposite face side making it parallel to the other flat face from the jointer, but also reducing board thickness to final thickness dimension. Step 4 is to use the jointed edge as a reference against the tablesaw fence to rip the other edge parallel to it and reaching final width dimension. This process is the ONLY way to ensure a woodworker can take raw lumber or even surfaced lumber that is irregular from the big box store/lumberyard and make it perfectly square, straight and parallel on all sides. Yes, you will see YT videos of people suggesting other methods as a substitute to jointing for the shop that doesn't have a jointer. I have even seen people try to suggest they can joint on a tablesaw which isn't true. IF your lumber is fairly straight to begin with, has not internal stress when cut and isn't twisted, then a woodworker can often get by with just a tablesaw and achieve acceptable results most of the time. When your lumber is more natural and hasn't already been pre-milled for you, you MUST follow the steps I describe above to get acceptable results. I hope this helps.

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RFGuy. Sorry to see you go. I have always valued you opinion on this forum. I will miss your content. My previous jointer was a small bench top jointer by Delta. I think it's even shorter than the SM Joiner but it will do 6" material. I surfaced the top and bottom of my material with a planer and then joined the edge to put against the fence. In talking with a fellow woodworker friend of mine he reminded me the batch of wood from this mill has had a lot of prestress in it. He purchased wood from the same lot I did and he was having issues with it pinching and binding in his saw. He suggests it's moving on me and it's not my saw. I'm beginning to agree with him.

[KCollins]

I suggest thee stop chasing thy tail be comparing edges of different boards.

You need a known straight reference(straight edge or table surface) to critique each board edge.

Your wisdom is sound JPG.