Help with Smoking Bandsaw Blade

[Ed from NY]

Hi

I got this blade smoking cutting C1080 steel at 215 FPM.

I looked up feed rates on machining manuals and it looks like it is right where it should be.

The feed was the lightest one that would prevent the saw from jumping. The blade came with the machine and is marked Lenox 4007278. I could find no reference to it. The teeth are 6/10, and by looking at the Enco site I think it is their bi-metal sold as Enco's.

If I'm cooking this blade I do not want to do the same with the next one

Should I be concerned? May be it is just the oil getting a bit hot

Any ideas?

You can see the smoke towards the end of this video.

"http://www.youtube.com/watch?v=NoldeJHtKZg"]YouTube - Enco Turn-Pro BandSaw - 2nd Cut - Square?

...and ... since I'm posting already... How do we make small corrections to the angle of the cut. Right now it is coming down and going off 0.080 (EDIT: Oops, the correct number is 0.008) in 4 inches, which is not that bad, but if it is something easy to improve we might as well.

Thanks!

[Dropout]

I'm not a big saw expert but:

The adjustable roller is too far from the material. It should be so close that it almost hits.

The smoke could be coolant vapour. It also looks like the coolant is not adjusted well. It should travel on the blade to the steel being cut, not drop as it does in the video.

[Ed from NY]

I hear you, can't move the roller any closer though, that is as far as it goes. I could get a loc-line for the coolant and get it closer to the blade

[One of Many]

Hi Ed,

Running oil, I'd expect it to smoke at that blade speed too. Look at the chips. If they are turning color from heat, the blade speed is too high.

I look at it this way. A cutting speed chart is a guide, not gospel. If time is money and the savings in time well covers the cost of a new blade, then do what ya needs tado. If half the speed gives 2-4x the blade life, then what's the rush? I'm usually doing something else while it is cutting anyways. I don't want to babysit the thing for fear of some sudden catastrophy.

.08 taper isn't all that bad in 4". You can tweak a new blade to cut straight if that critical, but the chances are high on 3/4" and smaller blades, that it will always wander in one direction or another as the teeth get some wear. You can end up chasing it forever, until you realise what you can live with to get just one more cut out of that blade. The blade guide bearing support blocks can be swiveled on some saws if not welded solid. Any taper compensation will be for that blade at that time.

These are beast of burden saws. I find it easier to see what I get on the first cut and add excess from there. If you are the only operator, at least it will be reliable with the conditon of the blade known. In a maintenance shop, no telling why the last person ran the inner or outer tooth edge on a weld or a hard spot and left it as a surprise. That will make .08 seem minor in 4 inches. LOL!

DC

[Superman]

The rear blade guide also looks adjustable ( slighlty ).

Could you adjust your rear vice jaw forward a couple of inches and the rear support the same accordingly ?

It may take lomger to cut, but to get less taper, turn the bar 90° to cut along the 4" edge.

---less pressure on the blade arm when cutting will also minimise taper---

[Ed from NY]

Hi Ed,

Running oil, I'd expect it to smoke at that blade speed too. Look at the chips. If they are turning color from heat, the blade speed is too high.

Oh! Okay, I looked at the chips and they are clear. But a lot of them are very small, like in furry... I suppose I need to increase the feed. I had reduced the feed as much as I could because I thought that is what was causing the smoke.

I'll try to put on a loc-line to get more coolant closer to the blade entrance and perhaps getting more going all the way. I suppose I can not really have coolant on top of the material as it would run and drip who knows where making a huge mess.

I look at it this way. A cutting speed chart is a guide, not gospel. If time is money and the savings in time well covers the cost of a new blade, then do what ya needs tado. If half the speed gives 2-4x the blade life, then what's the rush? I'm usually doing something else while it is cutting anyways. I don't want to babysit the thing for fear of some sudden catastrophy.

Got it

.08 taper isn't all that bad in 4". You can tweak a new blade to cut straight if that critical, but the chances are high on 3/4" and smaller blades, that it will always wander in one direction or another as the teeth get some wear. You can end up chasing it forever, until you realise what you can live with to get just one more cut out of that blade. The blade guide bearing support blocks can be swiveled on some saws if not welded solid. Any taper compensation will be for that blade at that time.

Ai!

I'm perfectly happy with 0.080 (EDIT: My bad, the correct number is 0.008) in 4" when cutting stock. If I live it as it is for now would I be able to correct it later when I decide to cutting square tubbing. Meaning does "not adjusting it" makes it more and more crooked?

Thanks DC!

The rear blade guide also looks adjustable ( slighlty ).

Could you adjust your rear vice jaw forward a couple of inches and the rear support the same accordingly ?

It may take lomger to cut, but to get less taper, turn the bar 90° to cut along the 4" edge.

---less pressure on the blade arm when cutting will also minimise taper---

You can adjust the angle of the rear jaw but you can not slide it. The guide also starts to hit the "table" if I try to move it further.

I could use a block and position the work closer to the guide. That is an interesting idea if I'm cutting 2" square tubbing for example

The first cut I took was of that same bar horizontally as you suggested. It took 1:45 min. The reason I took the second cut vertically was because I wanted to see what was the taper.

[DSL PWR]

I have a smaller saw than yours, but it looks like I have the same cheap style of blade guide on mine. The biggest problem is the how they cheaped out on the bearing blocks. On mine the tounge and groove has a lot of slop, so even when the end bolt is snug, it will rotate over time. I ended up getting it as square as I could, then I tacked it in place. The next big problem is the slide that you move in and out for larger cuts. This isn't rigid enough, or acurate enough to hold the bearings square thru its travel length. So even if you get everything set up in one spot, as soon as you move the slide all bets are off. You could try and see if a wider blade would fit in the saw.

I got sick of the poor design and build of my band saw, and bought an Ellis a couple of years ago. Now when the saw cuts with a taper I know the blade is done. I just did some 3 3/4 1018 round bar, and the taper was under .010".

Fuzzy chips could be several things
Too light of a feed
Too fine of a blade
Dull blade

I hope you get the cuts that you want out of your saw, but I know mine was a POS.

[One of Many]

The Turn-Pro brand is often the same iron as Grizzly, Jet, Wilton, Birmingham tags. Still import quality.

The swivel head versions I have seen used the 4x6 frame running 1/2" blades. DSLPWR is right. Adjusting the slider roller guide after getting it set to cut straight, changes how the blade travels in the bearings. Back to resquaring and compensating for drift, if you can't live with it.

As with any machine, there are several modes of thought and machine limitations that could be taken into account to get the best result, where and when critical.

Standing the material up verses laying it down:

The thinner cross section will cut faster, but problems that come with this are:

The taller the cut, the more chance of taper.
The taller the cut, the wider the adjusting support must be open at the top and too wide at the bottom.
The taller the cut, the feed rate drastically changes from top to bottom due to frame weight shift.

Laying the stock down still includes other issues.

More teeth in the material, the less bite it can get, forcing you to slow the feed rate to something the blade can handle. Sometimes a test in patience with a bad combination of material and blade tooth count or sharpness. But hey, if all is well, you might gain a straighter cut....

Was there ever a line in Star Trek where someone said. "Damnit Jim, It's a saw, not a laser" ?

DC

[DareBee]

I will add to what has already been said.
The taper is (I am quite sure) limitations to that bandsaws build design (yes I have used saws like that one).
You will get less than .005 taper on a HydMec, Ellis, Bomar, DoAll, Etc.
IMO your blade as too fine.
I wouldn't use any finer than a 3-5 TPI and I DO use 4-6 for everything (tube, solid, pipe, aluminum, tool steel, stainless, etc).
The only time I change to a finer blade is when I need to cut a pile of SS sanitary tubing (.060 wall).
I am not familiar with your blade choice but I will say that the higher end blades pay for themselves over the lesser blades by making more cuts per dollar spent.
I am fortunate (due to business accounts and co history) to be able to buy the good blades for what some people pay for the "cheap" blades.

[Ed from NY]

The biggest problem is the how they cheaped out on the bearing blocks. On mine the tounge and groove has a lot of slop, so even when the end bolt is snug, it will rotate over time. I ended up getting it as square as I could, then I tacked it in place. The next big problem is the slide that you move in and out for larger cuts. This isn't rigid enough, or acurate enough to hold the bearings square thru its travel length. So even if you get everything set up in one spot, as soon as you move the slide all bets are off. You could try and see if a wider blade would fit in the saw.

I got sick of the poor design and build of my band saw, and bought an Ellis a couple of years ago. Now when the saw cuts with a taper I know the blade is done. I just did some 3 3/4 1018 round bar, and the taper was under .010".

I suppose this is the guide that straightens the blade for the material... it does not have any play on the slide or the bearings. Everything looks pretty solid. The only thing is that there is some flex (not play) side to side when it is extended, but there is no apparent torsion flex. It actually feels pretty solid.

May be a project for one day would be to mill a new guide with dovetails and a gib, adding a second set of bearings next to the casting. So that the new set of bearings would straighten the blade up always in the same position next to the casting and the current set of bearings would just support it as it approaches the material. It should be a nice project and may get more consistency out of it.

This bandsaw was already a stretch for me, only got it because of the extra 20% off during a 2-day event. The Elis would be out of my range at this point.

Fuzzy chips could be several things
Too light of a feed
Too fine of a blade
Dull blade

I'll work on that

The Turn-Pro brand is often the same iron as Grizzly, Jet, Wilton, Birmingham tags. Still import quality.

The swivel head versions I have seen used the 4x6 frame running 1/2" blades.

This takes 3/4 x 0.035.

I'm happy with it.

I just want to get the most out of it.

It's 400 lbs and rather sturdy. The only other thing I see with it is that I wished there was a way to fine tune the 0, 15, 30, and 45 stops. There is a lock, but you have to put a square to it and fine tune by hand every time. If you set it it will hold, and there is absolutely no drift while setting it. The whole mechanism is very massive. But you still need to take your square out every time you change it. Or at least I have not figured out a way not to.

Standing the material up verses laying it down:

The thinner cross section will cut faster, but problems that come with this are:

The taller the cut, the more chance of taper.
The taller the cut, the wider the adjusting support must be open at the top and too wide at the bottom.
The taller the cut, the feed rate drastically changes from top to bottom due to frame weight shift.

Laying the stock down still includes other issues.

More teeth in the material, the less bite it can get, forcing you to slow the feed rate to something the blade can handle. Sometimes a test in patience with a bad combination of material and blade tooth count or sharpness. But hey, if all is well, you might gain a straighter cut....

Was there ever a line in Star Trek where someone said. "Damnit Jim, It's a saw, not a laser" ?

DC

LOL, and thanks, that will help!

I will add to what has already been said.
The taper is (I am quite sure) limitations to that bandsaws build design (yes I have used saws like that one).
You will get less than .005 taper on a HydMec, Ellis, Bomar, DoAll, Etc.
IMO your blade as too fine.
I wouldn't use any finer than a 3-5 TPI and I DO use 4-6 for everything (tube, solid, pipe, aluminum, tool steel, stainless, etc).
The only time I change to a finer blade is when I need to cut a pile of SS sanitary tubing (.060 wall).
I am not familiar with your blade choice but I will say that the higher end blades pay for themselves over the lesser blades by making more cuts per dollar spent.
I am fortunate (due to business accounts and co history) to be able to buy the good blades for what some people pay for the "cheap" blades.

This was the blade that came with the machine which is a Lenox 6-10 (unsure of the model number and specs). Unfortunately the spare blade I got is also a 6-10, but from Irwin.

Next time over I'll take your advice and get a 4-6 or 3-5 and look at the higher end ones as well.

Thanks!

[Edit]

BTW, I got a little loc-line kit, so I'll be able to move the coolant closer as well.

[HuFlungDung]

For an initial check, I'd clamp a good square in the vise, near the saw blade. Raise the saw and measure the gap between the square and the band. Check the gap with the saw near the bottom. If there is any variation, that is the natural 'taper line' which the saw will cut along, no matter what you do with the blade guides.

I run a bandsaw which I built myself, and over the years, that is what I have observed: if the band's tooth set is undamaged on both sides, the saw cuts perpendicular to the pivot plane of the saw axle. If you have some way to adjust that axle angle, do so. Otherwise, shim beneath the work, or shim the infeed table to raise the work so that it is perpendicular to the saw pivot axle plane.

[Ed from NY]

For an initial check, I'd clamp a good square in the vise, near the saw blade. Raise the saw and measure the gap between the square and the band. Check the gap with the saw near the bottom. If there is any variation, that is the natural 'taper line' which the saw will cut along, no matter what you do with the blade guides.

I run a bandsaw which I built myself, and over the years, that is what I have observed: if the band's tooth set is undamaged on both sides, the saw cuts perpendicular to the pivot plane of the saw axle. If you have some way to adjust that axle angle, do so. Otherwise, shim beneath the work, or shim the infeed table to raise the work so that it is perpendicular to the saw pivot axle plane.

You got it!

and

I'm an idiot!

The taper is 0.008 in 4 inches not 0.080

I guess that explains why I was happy with such a large taper :lol:

Anyway, the taper related to the axle angle is about 0.022 in 11 inches which kinda explains the 0.008 in 4 inches or 0.002 per inch.



[Edit]

Changed the video to reflect the real number.

Based on the numbers you guys gave me I should just celebrate while apologizing.

Thanks!