help needed

[solarman216]

OK you guys and girls are any of you butchers that operate a Biro 3334 meat saw, I have a big problem with one of my customers saw, it keeps kicking blades off and cannot fathom why? Rick

[solarman216]

to illustrate the importance that this deserves, £100 goes to the man that can solve it, Rick

[AlexD333]

Originally Posted by solarman216

to illustrate the importance that this deserves, £100 goes to the man that can solve it, Rick

The answer "if you cant fix it, it's broken"

[solarman216]

Originally Posted by AlexD333

The answer "if you cant fix it, it's broken"

very rare am I defeated, but this one is a real pain both pulleys are in line, belt tension is correct but still sheads blades, Rick

[AlexD333]

Can't see a forum for it, or any problems on Google with same symptom

I did find this though, has a few measurements that may help

http://www.birosaw.com/products/wp-c...ssseries92.pdf

[Lazy-Ferret]

Not sure if you have the manual...

http://www.waltonsinc.com/PDF/Model%...w%20Manual.pdf

On the Band saws I have used in the past (not Meat), assuming it was all working fine, and then started playing up after a blade change, blade run off was normally caused by a bad welding in the band saw blade loop, where it was not properly aligned, and when you looked closely, the back edge had a small step at the join.

Now knowing you, you have already tried a new blade, but is it from the same manufacturer, e.g, is there a manufacturing fault?

[Lazy-Ferret]

Just found this...
http://meatcuttersclub.activeboard.c...topic=44059424

Read down to the bottom, not sure where they mean to put the metal though.

[zippy656]

Ah, its a band saw.

First check rubbers on wheels. Dammage can cause it to jump off. Smooth flat or convex

Second, check top wheel moves freely, not round and round but tips back, as needs to keep blade runnin in center of rubber on.wheel, (only if rubbers are convex)

Third. If rubbers flat, top wheel should be tiped back a little, pullin blade back.

Fourth. Chech top and bottom.wheel guides are free running, not worn with chips dents or chunks missing.

Last, the guides that the blade is pushed onto when cutting is set correctly. Both set same one above table, the other below, if to far back. After cutting the blade will sprin forwards, jumpin off wheel.

Info from woodworking machines, 20+years. Not meat. But think info still sound as machines are the same.

[bud]

Same principle as a band saw in a Saw mill...and resaws..(which is what I do)

THe saw will need tracking to run true....

it could have a crook /worn bearing which will create more pressure on one side of the band then the other causing it to move forward of the wheels.

[rustic]

Having read the posts and the links, I find it amazing that the blade stays on at all.
A bit like how a train stays on the track at over 100 mph, with a very small lip on the edge of the wheel.

It's all about curvature of the pulleys on the saw, which should be convex so if they are aligned correctly, will self centre, and for the train, about taper on the wheels.

Cutting edge technology.

[rustic]

Maybe time for some lateral thinking.
Maybe the blade is coming off as a consequence of something else rather than the pulleys.

If the blade jams in the meat a little, then as the drive pulley rotates it will squeeze the blade off as it slips.
So what is the blade tension like, it needs to be quite high, and consistant.

What you don't know, is which pulley the blade is coming off first, but more likely the drive one.

[solarman216]

Thanks for suggestions so far, already have the literature suggested but neither gives any set up info for blade alignment other than tension, which is set with a feeler in the spring, when the feeler becomes tight the spring is compressed correctly, both pulleys are in line and no play in the bearings, the motor is powerful and on startup you can see the blade pull forward a little on the bottom drive pulley, this is as the blade leaves the pulley, this to me is saying that the blade is going slack or there is some other distortion going on, but this machine is very heavy and very solidly constructed so hard to see where any flexing can take place, have Emailed the manufacturers for info, I have found some forums re this issue and some say these machines are renowned for this fault but no info as to the cure, Rick

[Banshee]

Originally Posted by AlexD333

The answer "if you cant fix it, it's broken"

Exactly what I was going to write

I had to read the thread title and user 3 times and then still had to open it to check I'd read it correctly

[rustic]

Originally Posted by solarman216

to illustrate the importance that this deserves, £100 goes to the man that can solve it, Rick

I speak for myself and maybe a few others, No need Rick, ok it's part of your work and income, but then you give part (a lot) of your work time and income to help members on this forum too.

About time we can help you for a change.

I hope you can get it sorted.

If I work on something that is broken, I see it as a challenge to be able to fix it, sometimes with more time and effort than it's worth...
I think most of the members on this forum are like that too.

Good luck,
Rustic

[AlexD333]

Originally Posted by Banshee

Exactly what I was going to write

I had to read the thread title and user 3 times and then still had to open it to check I'd read it correctly

With a look of confusion on your face I bet