Bandsaw Trouble? burn marks and smoke!

[Travis]

TonighI was using the band saw and the shop become very smokey. It was charring the wood (Grizzly 14" w/ half inch blade) it even darkend the wood on straight cuts. Please see photos. I do not have a lot of expereince with this tool and was wondering if it is normal.



but it sands out nice...

[DaveO]

What have you been cutting with that blade? If it has developed a pitch coating on it it will have more of a tendency to burn. That curve looks a little sharp for a ½" blade without kerfed release cuts. But the burning is also on the straight sections Are both your bearing guides coplaner to each other? If they are slightly twisted it would cause the blade to bind and cause burning.
Dave

[cskipper]

Burn marks and smoke are never good when woodworking (okay, unless you are actually wood-burning)!

[skysharks]

I am guessing but I would take a look at binding the blade up and maybe feed rate.
Travis were you going real slow?
Looking at the photos it looks as if the blade was rubbing on the wood the entire time you were cutting.
Like maybe the wood closed up after the teeth went thru it, but you were cutting plywood so that doesn't make sense.

[Bill Mason]

Maybe my eyes are playing tricks on me but are those teeth going the wrong way?

Bill

[pcooper]

My first impression on looking at the wood was the blade is going the wrong direction, and the picture is a bit hard to tell, at least for me, but I do think maybe the teeth ARE the wrong way. I've done that too, and for me that was the kind of cut I got too.

[walnutjerry]

I have to go with the blade is on backwards----------seems evident in the picture.
BTDT

Jerry

[Wildwood]

No, burning wood is not normal.

At first glance, thought resinous material and dull blade the problem. I can't tell if blade is on backwards. Since you didn’t mention blade drift, not sure if blade is dull or not. So, am guessing whatever is sticking to the blade, and worn blade the problem.. From looking at the photo, estimated your using a 6 TPI hook tooth blade, which might not be best choice for this type of cutting.

A better choice for this type cutting might be blade with standard or skip teeth which better suited to handle the radius and thickness your cutting. Whatever sticking on the blade your using now would also have same affect on these blades too!

So would recommend trying a blade with less teeth per inch, either 3 TPI hook or 4 TPI skip tooth blade next time. The skip tooth blade will leave a better finish that the hook tooth. Stoping to clean the blade may be required as well.

[Joe Scharle]

This from Shopsmith. I keep a copy in ziplock on the saw

Bandsaw Blades and Speeds
Characteristics
Recommended Use
Recommended Speed**
1/16" Woodcutting Blade* - 24 teeth per inch, 1/32" minimum turning radius
For extretmly fine detail work only. Use for wood and plywood up to 3" thick. Not for heavy-duty cuts or resawing.
A (750 RPM, 2160 FPR) for hardwood. B (850 RPM, 2450 FPM) for softwood.
1/8" Woodcutting Blade - 7.5 teeth per inch, 1/4" minimum turning radius
For very fine detail work only. Use for wood and plywood up to 3" thick. Not for heavy-duty cuts or resawing.
C (950 RPM, 2750 FPM) for hardwood. D (1050 RPM, 3000 FPM) for softwood
1/4" Combination Blade - 6 teeth per inch, 3/4" minimum turning radius
A good general purpose blade for wood, plywood, plastics, particle board, and soft non-ferrous metals. Limit resawing to stock 4" thick, metalwork to stock 1/4" thick.
B (850 RPM, 2450 FPM) for hardwood. C (950 RPM, 2750 FPM) for softwood. Slow (700 RPM, 2000 FPM) for other materials.
1/2" Combination Blade - 4 teeth per inch, 2" minimum turning radius
For heavy-duty cutting fo wood, plywood, plastics, particle board, and soft, non-ferrous metals. Suitable for resawing stock up to 6" thick, and metalwork in stock up to 1/2" thick.
Slow (700 RPM, 2000 FPM) for hardwood, softwood, and other materials.
5/8" Woodcutting Blade - 3 teeth per inch
For heavy-duty resawing. Efficiently handles wood up to 6" thick. Straight cuts only. Note: Set the tension scale at the 1/2" setting.
Slow (700 RPM, 2000 FPM) for hardwood and softwood
Several blade manufacturers make bandsaw blade stock for a variety of special purposes -- intricate scrollwork, cutting iron pipe, etc. If you need a special blade, you can have it made at a well-equipped commercial saw shop. Use only high-quality blade stock 1/16" - 1/2" wide. Be sure that the finished blade is 72" long, plus or minus 1/2" and that the weld is ground perfectly smooth.
*Caution: Do not use 1/16" blade without special guide blocks. Failure to use special guide blocks will ruin the blade and damage the standard guide blocks. **Note: these speeds are for 60 hz. operations.

[cpowell]

I'm NOT piling on...seriously.

Were you running the DC? I just imagined very hot chips going into a DC with a whole lotta air (oxygen) flow. Probably not hot enough to ignite...but I would definitely open the DC bags and take a peek to be sure. Just a thought. I found a screw in some stock I was resawing once and I saw sparks. It concerned me enough to check out the bags. Better to be sure. (I also discovered that a steel screw dulls a silicon steel blade beyond usefulness in the blink of an eye)

Not sure from the pic if the blade is backwards but I have done that - exactly once - and check every time I mount a blade now.

A 1/2 blade sounds narrow for the tight radius outside curve cut.

BTW - nice looking ply after sanding. Baltic birch?


Chuck

[Travis Porter]

The blade looks upside down to me as well. Teeth should be pointing down. Otherwise, time for a new blade IMO.

[Joe Scharle]

How do you mount a blade upside down?

[Bill Mason]

Not that I would know first hand...

Turn it inside out first and then when you put it on, the teeth are going the wrong way.

Bill

[gazzer]

Same thing happened to me once. Sure enough, the blade was upside down. Smoked up the shop big time.

-G

[Travis Porter]

I have done it once myself on the bandsaw. Just last week I put a shaper cutter in upside down with similar results.