Band saw blade breakage

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Hi all, I just got a new FMB Phoenix for a big job and I keep braking blades!?I broke the blade in properly and I'm cutting bundles of 9, 1 1/2" 16gauge square tube on a 45.I've got the down feed set pretty slow so the motor isn't straining. Can't figure out what I'm doing wrong. Help please.Also I'm running bandaid 1:10 per spec. with the tap full open.Thanks for looking
Reply:to much blade tension.    Probably breaking when one of the cut parts tries to drop but gets pulled sideways and jams into the blade.     You might have to baby sit the saw and clear every part in the bundle as its cut through.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:Here is a pic, it definitely has signs of stress. Attached Images
Reply:Also check your guide bearings. They can cause that type of problem if to tight.Millermatic 252XMT 304'sDynasty 280DXHypertherm PowerMax 1250Miller Trailblazer 302 EFIOptima PulserXR feeder and XR Edge gun and more athttp://members.dslextreme.com/users/waynecook/index.htm
Reply:Probably parts moving in the vise as they are being cut. Lots of problems with vises not holding parts from moving. It helps to use additional clamps outboard of the vise to keep the parts from moving, also to cover stationary face of vise with sandpaper/grit surface to help with traction.  Parts of the bundles are moving as you cut, break blades faster than you can change them. Most saws I have seen the back jaw is moved to the 45 position then the front moveable jaw is left trying to clamp the work while the jaw itself is sliding toward the blade. Extra clamps to hold work together and to the saw surface will fix the problem.
Reply:Originally Posted by GjertsonHi all, I just got a new FMB Phoenix for a big job and I keep braking blades!?I broke the blade in properly and I'm cutting bundles of 9, 1 1/2" 16gauge square tube on a 45.I've got the down feed set pretty slow so the motor isn't straining. Can't figure out what I'm doing wrong. Help please.Also I'm running bandaid 1:10 per spec. with the tap full open.Thanks for looking
Reply:Thin gauge tubing is a nightmare for bandsaws and 45degree miters are nightmare to clamp well.  suggestions:-If the blade in the pic is what you're using, it looks too course.  To made interupted cuts in 16g tubing all day I'd run a 16-18t blade.  Leave a little speed on the table but make up for it by not eating blades.-crank up the blade tension.  The difference in presure between the interupted cuts (teeth between the two walls of the tubing) is what's fatigues the blade.  This is compounded by the low tooth count.-welding the ends of the tubing will help.Syncrowave 300Maxtron 450, S-52E, 30A
Reply:What kind of blade are you using? That type of break is caused by work hardening. That generaly happens when the blade is too thick for the radius of the wheel. Normally the blade should run at 44000 lbs. per square inch of tension.  Mac
Reply:The guide arms might be loose  or you over feed the stock on the blade. Or lack of band tension .PlasmaCam CNC cutterLathe and Band SawClamps
Reply:Originally Posted by wendellThin gauge tubing is a nightmare for bandsaws and 45degree miters are nightmare to clamp well.  suggestions:-If the blade in the pic is what you're using, it looks too course.  To made interupted cuts in 16g tubing all day I'd run a 16-18t blade.  Leave a little speed on the table but make up for it by not eating blades.-crank up the blade tension.  The difference in presure between the interupted cuts (teeth between the two walls of the tubing) is what's fatigues the blade.  This is compounded by the low tooth count.-welding the ends of the tubing will help.
Reply:Thank you all so much for taking the time to give advice. I have my LWS has been suggesting a 5-8. That may be part of the problem. The FMB does have one heck of a vice on the plus side though.
Reply:Originally Posted by GjertsonThank you all so much for taking the time to give advice. I have my LWS has been suggesting a 5-8. That may be part of the problem. The FMB does have one heck of a vice on the plus side though.
Reply:the blade came with the saw lasted forever. after that ive been buying my blades from grizzly and thay are doing the same thing.so i bought the best. there working great Attached Images
Reply:Originally Posted by dave powelsonAre you going to weld the bundle ends to stabilize them in the cut?If not-then forget about cutting bundles.
Reply:What are those saw blades ?PlasmaCam CNC cutterLathe and Band SawClamps
Reply:there lenox classic bi matel 3/4x.035 6/10 vari-tooth blades. Attached Images
Reply:Looks like a you have a strong band saw! I got 501 bi metal blades too , I normally use it for cutting structural steels.PlasmaCam CNC cutterLathe and Band SawClamps