I am relatively new to woodworking, but I haven’t ever had a problem like this before. I am attempting to resaw some 4/4 soft maple using the only table saw I have – a RYOBI 10″ contractor saw. I have resawn a 2X4 pine board without issue, but when I attempt to resaw the soft maple, I get severe burn-marks on the wood. I noticed that I was using my 80-tooth crosscut blade, so I switched to the stock combo-blade (rarely used) and still had the same issue – severe burn marks on the wood.
I did notice that if I rip the board, I get burn-marks on the inside cut (closest to the rip fence), but not on the outer waste-side of the cut. Also, using the cross-cut sled produces no burn marks.
I have checked the alignment of the blade to the fence and I cannot see that the blade is out of alignment. Also, I have tried resawing slowly, then moderately fast, but the marks are still there with about the same severity.
Any suggestions?
Replies
Thats a lotta teeth for resawing, try a 24 tooth rip blade.
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It would indeed be a tragedy if the history of the human race proved to be nothing more than the story of an ape playing with a box of matches on a petrol dump. ~David Ormsby Gore
I find that a fast feed rate works best when I am experiencing burning with the tablesaw. Use a good (aftermarket) ripping blade and make sure that it is SHARP.
Is it possible the board is warping during the cut? I found one board today that would completely close the kerf 8" behind the rear of the blade when ripping. It was completely dressed, but likely reaction wood. I tossed the board.
Chris @ flairwoodworks
- Success is not the key to happines. Happiness is the key to success. If you love what you are doing, you will be successful. - Albert Schweitzer
To add on to Chris's remarks: Are you using any kind of splitter? That would probably help. How wide a piece are you trying to resaw?
-Steve
Being 4/4 wood, I am resawing it down to 2/4 (1/2"). I don't have a riving knife that doesn't contain a blade guard, so I am wedging the wood with an 1/8" piece of hardboard close to the end of the board. The board is about 3' long.It looks to me like I am going to have to get a good rip blade.
No, I meant in the other direction. In other words, how deep is the cut?
-Steve
Oops...sorry. I am taking about 1-3/8" off each cut.
Forgive me if you know this, but your fence should not be parallel with your saw blade. It should be skewed away from the TS blade by 1/64" by the end of your table. Skewing the blade ensures that the wood between the fence and the blade will only be cut by the teeth on the front of the blade, rather than being cut twice by the teeth on the front and back of the blade. It also prevents the wood from rubbing against the saw blade body on the fence side of the blade. As this is usually the piece of wood that is the keeper, I am willing to ensure its burn free edge.
Thanks for the reminder, and you are correct. The back of the fence is about 1/64" different. I usually align using the miter slot to the left of the blade.
Maple burns easily under the best of conditions but it sounds like your rip fence is misaligned. Unless you have tuned up your saw and know that the miter slot is parallel to the blade, it probably isn't, so using the slot to align the fence only repeats the error.
If you want to quickly align the fence to the blade, first cut a small block of wood two or three inches square and an inch or so thick. Next raise the blade to almost full height and unplug the saw for safety.
Then, place the block, one wide face down, against the fence and slide the fence over until the saw's teeth just barely brush against the face of the block at the in feed side of the blade. If you gently rotate the blade a fraction of a turn you can see, hear and feel when the teeth are rubbing slightly. Do the test with the fence locked in place.
Now slide the block to the outfeed side of the blade and, if everything is aligned, the teeth should also be just brushing the face of the block. If you want to be a bit more precise rotate the blade so that the same teeth that were brushing the block in the front are also being used in the back.
If the teeth aren't brushing the same way front and back, the fence is out of line. In your case you will probably find that the fit is too tight at the outfeed side. If the fence is aligned properly there is no need to give it additional toe out which can cause other problems.
John White
Kgeorge , I don't know if you have a jointer , but if so trie face jointinng &edge jointing to get a perfect 90 before ever cut& use the mentioned 24tooth blade. as well I have had much sucsess by making my first pass about 1" deep whitch releases some stress , &then more passes about 11/2" per until your final height. this has served me well over the past 20 or so years !best of luck
Thanks everyone for your input. I will pick-up a new blade tomorrow and give it another go.
a RYOBI 10" contractor saw..
I had a old RYOBI.. 3000? with a slider. I LOVED that saw..
I do not use maple often but many other hard woods..
Purbleheart, Hickory, and (Ash) and others.. ALL can sometimes be a bummer!
I had access to a Top Of The Line FELDER, I think is was about 12 HP 3-Phase or something like that.. Guess what.. Hand feeding my large Purpleheart BURNT!.. Power feeder was MUCH better but still a hint of burning on a commercial saw! Reaction wood? I have no idea..
I would say.. Cut a 'bit' oversize and joint to final.
EDIT:
Thats a lotta teeth for resawing, try a 24 tooth rip blade.
I found 'whatever' the original bade was on my saw was MORE than OK.. BUT I will go along with the other post to many teeth for thicker woods... I do not remember how many teeth the original bade had.. But seems reasonable to me.
Edited 2/1/2008 9:32 am by WillGeorge
I agree with the recommendation to use a rip blade, but in addition to that, I would try a half fence as well. That would prevent any pinching between the blade and the fence.
Jeff
Forgive me for my ignorance, but what is a half-fence?
Also called a rip fence, it is a axillary fence clamped to your main fence, that does not extend past the arbor of the tablesaw, allowing the sawn material to spread if it wants to.
jeff,
An axillary fence fits under your armpit, as compared to an auxillary fence, right? ;-))
Ray
Yep, I saw that, was too lazy to go back and edit the spilling.
kgeorge,You are experiencing the classic problem of poor table saw setup. Ripping will reveal the problem while crosscutting will not. Sometimes a contractor's type saw just can't be set to avoid this problem 100% of the time.As John has said, maple can test the patience and technique of the best craftsman and the setup of ANY saw and blade. If any wood is going to burn when ripping, it is maple. When this kind of thing happens, though, it's usually the combination of many factors, not just a tweak here or there. You have described a number of factors that allow acceptable results with softwoods, and under less than accurate setup, that just kill you when using maple.Of course, the crosscut blade was wrong to use. The tooth configuration is all wrong, and even it were a rip blade, it would not give you good results because the number of teeth is far too high. Then you went to a combination blade, which I'm going to assume is the one that came with the saw. Probably very low quality.Even a medium quality combo blade, such as a 40 tooth Diablo or Dewalt blade would do an excellent job IF your fence is correctly set. A real ripping blade would be even better. My Freud FTG 24 tooth ripping blades can't be beat.Your fence IS set too close to the blade on the outfeed side. No matter how you are measuring, the "test" of the setting is the fact that you are burning the wood (but this is only a valid conclusion if you have a good blade AND the blade itself is correctly aligned, using the miter slots as reference, or as John has described.)The subject of "short fence" is one of those issues that typically produces dozens, if not hundreds of responses with people lining up into one of 2 camps, pro and con.In Europe, Australia and New Zealand, woodworkers grow up with and use machines in which the rip fence is adjustable in the longitudinal direction and can be set so that the back end of the fence is just barely beyond the the front edge of the blade, or certainly not beyond the blade arbor. The wood is NOT supported beyond that point in the ripping operation, allowing any wood movement to the right of the cut to be free.If that wood curls TOWARD the blade, it can pinch the rising rear teeth, increasing the liklihood of kickback. If the wood curls AWAY from the cut, and is still in contact with a fence, the whole board can be forced to the left. But if there is no fence to trap the moving wood, that won't occur.Saws sold in North America typically have long fences which support the work all the way through the rip cut and cause the problems which the typical European saw avoids (I am in the short fence camp).I've attached a picture of a rip fence on a Felder sliding table saw. Notice that it appears to be set so the back edge is about even with the rear teeth of the blade in this picture. It can be set anywhere along its length that the operator desires. An "American" long fence can be "converted" to a short fence by clamping a length of wood to accomplish the same mechanical purpose. And the Unifence adjusts in the same way.It's not obvious in the picture, but the table to the LEFT of the blade slides in the direction of the cut. The wood can be clamped to the table and ripped without any use of the rip fence. In fact, the rip fence is seldom used at all on such a saw for anything other than as a material stop for high accuracy in repeated crosscuts.There are many workers who avoid ripping with a rip fence at all cost, preferring either use of a sliding table saw or use of a band saw, followed up by cleanup on a joiner. But I won't mention that as THAT subject frequently starts war . . . er "discussions" of the different techniques.Rich
Edited 2/2/2008 8:49 am ET by Rich14
Rich,Thank you very much for the explanation.What you said makes total sense to me, so either you explained it very well, or I am thinking clearly (probably more the former than the latter).Just for good measure, I went out and purchased an Olsham 24T Rip blade, re-checked my rip fence, put my home-made (it was a pain since the original plate is only about 1/16" thick - I have a Ryobi BTS20 portable tablesaw) zero-clearance plate in-place, and did another resaw test with about 1-1/4" thick 4/4 maple. Low-and-behold, no burn marks!I like the idea of a half-fence. I think next time I will use it and see if I get better results.
"it was a pain since the original plate is only about 1/16" thick:"Yup rip blades are full kerf, 1/8""I like the idea of a half-fence. I think next time I will use it and see if I get better results."Unless the wood really wants to move, the "half" fence will not necessarily give better results with well-behaved wood. But one never knows when one rips a board what stresses may be in there. The half fence and the riving knife, along with the crown guard of the European type of saw increase safety compared with the usual equipment on a contractor's type of saw.It's certainly possible to get excellent results with your equipment. Use good blades, keep the saw in proper adjustment, know the safety factors, always use the splitter and guard, don't let the piece rotate into the rear of the blade.Good luck!Rich
"Yup rip blades are full kerf, 1/8"..."What I was referring to was that the throat plate on my table saw was only about 1/16th of an inch thick, so making a zero-clearance plate is difficult (I used 1/8th inch paneling and created 1/16th of an inch rabbets around the edges).
Short fence.. did you say short fence? ha.. ha...
Regards...
Sarge..
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