I started to trim some ends off some 14″ w. pieces of Pine today – and noticed that the last few inches of the cut it bumped out slightly. This as though at that point the blade was instantaneously pushed away – not just a gradual change. The relief at this point is about 1/64th. Tried several other pieces of differing width/material and the result the same. The blade is newly sharpened and this occurred using three different sleds including one that had new runners and had just been calibrated. Riving knife removed. All cuts from left side of blade. Oddly could not replicate on right side and also used a Incra mitre bar cutting on left side and had no problem. I don’t recall ever having this issue before – have had no damage to table saw or sleds. Any help/suggestions/comments would be appreciated.
Replies
I think I see an outfeed table in the background. Check the transition from the saw to the outfeed for a bump.
Pulled the outfeed table away to check- didnt affect it.
Just a guess - if the blade is not parallel to the slot the crosscut sled is riding in, it could cause this. In your case the back of the blade may be rubbing on the board as it passes and pushing your work piece to the left. If this is the case, cutting on the right side would not cause the issue since there would be a gap at the back of the blade.
Going to check the slots again, the right was checked recently and was ok. We'll see.
“[Deleted]”
Does the saw have a riving knife or splitter? Perhaps the sharpening shop made the blade a touch thinner and your stock is bumping into it. Cut a board almost all the way through and pull it back, then with the saw off push the stock on the sled to where the "bump" occurs and look for points of contact.
_MJ_ The blade was a newly sharpened Forrest WWII - and hadn't had any issues with the others - same model. It occurred to me that the riving knife might be element. Took it off for some cuts no difference including the following first rounds. So, this morning first rounds, I tried opening up the distance between the left mitre slot and back of blade - starting at +.005, .010, .020 - still had problem with WWII. Second round. Put a 80t Freud Cross Cut blade on which has narrower tooth and plate. It still had some of the same issue with left mitre slot even front/back of blade but much less. Then if I added +.004 between left mitre slot and back of blade the problem disappeared!
A note when first looking at the problem with WWII. The issue happens when stopping the cut just as front of blade finishes the cut (8 " wide piece) - which is fairly typical. Additionally, I observed that when the first part of the work piece was fed in the front edge cut cleanly then as piece went further the newly cut edge started to touch the blade plate around the center of plate (maybe a bump?) and then moving board further the "teeth on the back of the blade started to cut basically fresh material"? If I moved the piece all the way past the blade the cut was clean. Strange. This is not safe or practical unfortunately moving all the way through. I'm not sure if there is an issue with the WWII plate or not - never had any issues with resharpens - and always ask to check run-out and fix any plate issues etc.etc.
I tried to make that as clear as possible.
Keep in mind that I am guessing at possibilities for a setup I cannot see. If the newly cut edge is touching the plate of the blade your system has an alignment issue somewhere. Some 'upwind' scratches from passing the back of the blade could be considered normal, but not hitting the plate.
My next guess is the table/miter slot alignment to the blade. The issue not being on both sides could indicate feeding into the blade plate on the one side and away from it on the other. **Just saw that @DStevick had this up top in comment #2...I'm a little slow sometimes.
Yes, familiar with very light upwind scratches - this was not even close to that. Again, never seen that happen before. As mentioned I checked the left mitre slot at even front to back - had the problem then added +.005 - .020 still had problem with WWII. At +.020 that's quite an opening up and would have expected to see some resolve. So then with Freud blade problem is basically eliminated with +.004-.005 difference between left mitre slot at back of blade. I'm thinking it's the blade. The arbor bolt is tight. I can get even front to back alignment on both sides of the blade with digital gauge.
There seems to be three variables at play:
1) the sled
2) the blade
3) the Incra mitre bar
If the issue only occurs when using the sled and the WWII blade that leads me to believe it's an issue with the sled.
Or have I misinterpreted something?
I used three different sleds, one brand new as mentioned. Not sure about the Incra - calibrated it some time ago. At this point blade seems like most likely culprit.
Ok I hadn't read that you had used three different sleds.
iIf it happen with three different sleds, I doubt it's the sled but would lean more toward the blade.
Newly sharpened blade could have an issue, it happens. If it were mine, I would remove the blade, clean all mating surfaces, replace, yest cut.
This forum post is now archived. Commenting has been disabled