Help with resawing

[Brian Hale]

First attempt at re-sawing something happened i can't figure out. I've got a 4/4 x 8" x 18" long piece of ash, jointed on one face and one edge. I'm trying to saw it into 3 roughly equal size pieces. I set the fence so i don't need to move it between cuts. The fence is set for blade drift.

The problem..... On 2 different cuts, at different parts of the board, i got a large, earth-shaking bang. :eek: (LOML heard it upstairs) The blade didn't stop and i can just barely see it in the cut. I can't find anything wrong with the blade (1" carbide tipped Lennox Tri-Master) and the saw seems to be aligned like it was before the cut.

Any ideas? This can't normal, is it?

Brian :)

[lou sansone]

Have you ever had this happen before? If you saw another piece of wood does it happen again?

lou

[Stu Ablett in Tokyo Japan]

Unless the wood cracked because you cut some kind of stress point away....?

Did you only hear it, not FEEL it?

What about a tire slipping?

What kind of BS is is?

I'm sure I would be freaking out about something like that, I have a highly refined "Oh no, I could lose a finger doing this" meter built in, and I'm sure that would have been off the scale :eek:

Check the whole machine over, you could have a loose bolt or something, as the saw is worked more, something bends, or twists and then lets go, thus you get your "Bang".........?

Cheers!

[Brian Hale]

I've never re-sawed before and i'm afraid to try it again as i'be real unhappy if i broke this blade. Also, the saw is a new MM16 that i brought home last weekend.

Brian

[Brian Hale]

Stu, yes, i felt it. Almost like the board jumped up and then slammed back down on the table. I was about 8"-10" into the cut. I looked the saw over pretty good and called Mini Max. They didn't really have any answers but also suggested checking everything out. Every bolt i can find is tight and the drive belt tight.

Yes, i freaked out the first time it did it. The second time was just tooooo much!

Brian

[Mike Wenzloff]

Hi Brian,

fwiw, I've had Cherry shatter when resawing--quite literally shooting shards of wood clear across the shop. It was load. Internal stresses can make wood, uh, make a lot of noise.

Ash is another wood that can have a lot of internal stress, just like Oak.

Assuming that the blade is running true, the saw every other way operates properly, I cannot see a reason not to continue.

That said, you really need to check to make sure the saw is assembled well, everything tight that should be, the wheels running fine, etc.

I would also test cut in something other than the board you were cutting once you have ensured the saw is operating properly before cutting that same board.

Take care, Mike

[Richard Wolf]

I have heard other people have this problem. If I can remember, it is from not enough tension on the blade. A slack starts to build up and the blade finially slips on the wheel. If you are using the tension guide on the saw you are not putting enough tension on the blade. For resawing, the guide on my saw is well past the indicator for blade size. It is almost impossible to over tension good blades.

Richard

[Jim Becker]

Brian, take Richard's advice to heart no matter what...that Lenox blade needs to be tensioned properly and it's way above what the on-saw guage will indicate for a 1" blade. Not even close! On my MM16, the 1" Trimaster tensions (using the Iturra meter) near the very top of the scale on the saw.

[Brian Hale]

Thanks guys!

I sorta suspected that might be the problem. I tensioned the blade per the instructions in the MM16 manual that i downloaded from their website. Back off the guides, start the saw and slowly loosen the blade till it startes to vibrate. Then begin to tighten it till the vibration stops and turn the wheel a 1/4 turn more. This put the scale about halfway between the 1 1/4" blade mark and the top of the scale. Should i go for more?

How much should i tension it? Is there a number? I've read that each blade is different, even 2 identical blades.

What about the method where you clamp a set of calipers to the blade when it's loose and then tension it till the caliper reads .002" or .003"

Or is this more of a "just experiment till it feels right" sorta thing? :confused:

Brian :)

[Jim Becker]

Brian, the "flutter method" is fine for steel blades, especially low-tension blades like TimberWolf, but not appropriate for a TriMaster, IMHO. I bought a tension gauge from Iturra (their house model) and my TriMaster is tensioned "about right" when the on-saw guage is well above the 1.25" mark. Well above it. Crank it up!! And yes, every blade is different. I tension a 1/2" Timberwolf AS (wet work blade) to well above the 3/4" mark on the saw. Once I set a particular blade with the meter, I mark the saw for future speed.

[Brian Hale]

BTW Jim, Dain said Hi!

[lou sansone]

Brian, the "flutter method" is fine for steel blades, especially low-tension blades like TimberWolf, but not appropriate for a TriMaster, IMHO. I bought a tension gauge from Iturra (their house model) and my TriMaster is tensioned "about right" when the on-saw guage is well above the 1.25" mark. Well above it. Crank it up!! And yes, every blade is different. I tension a 1/2" Timberwolf AS (wet work blade) to well above the 3/4" mark on the saw. Once I set a particular blade with the meter, I mark the saw for future speed.

I would have to agree with jim on this one. You all know I am a big proponent of the flutter method, but the trimaster is in the range of 0.052 thick If my memory serves me. that is pretty stout and the flutter method is going to be hard to use with it.
lou

[Mark Singer]

I have a couple of Trimasters and the only time I heard a bang was when the blade broke...carefull not to overtension it! In my Aggazani I have the 1" Trimaster and take it up to 20 on the visible scale...with a 12 " resaw of Paduk or Jatoba maybe 25...no more....Let the blade do the work ...push slow and easy....

Try just cutting some boards laying flat...just to make sure it is ok!

Untension the blade when not in use...I then push the safety switch so I can't accidentally start it untensioned..

[Jay Knoll]

Brian

I just finished ripping some 2 1/2" strips off of some wide 8' long 3/4" thick cedar. By the time the rip neared the end of the board, the gap at the other end between the narrow ripped board and the wider remainder ranged from 4" to 6", so I am assuming that there was a lot of stress in that board that was released when I did the rip cut. I check it with another board, it wasn't jointed but laid flat on my bench without rocking when it was on its edge, I got the same result.

I haven't done a lot of resawing with long/wide boards so I'm anticipating with interest if I will experience the same thing you have gone through. Having read your post earlier in the day I was amazed to see the wood "moving" as much as it did when I did the rip cuts.

Mark, thanks for that great hint! I think I've forgotten to retension the blade and turned on the saw more times than I care to admit.

Jay

[Dee Dee Martin]

I've gotten a "bang" on my MM24. It was caused by me being "timid" when feeding in my board to be resawed. It was a short piece of stock, and I had the leading edge, up off the table. When the blade started into it, it banged it down hard onto the table. Quite a pop. And, it wasn't real obvious where the noise came from.

Make sure your stock is firm against the fence, and the edge flat on the table.