Band Saws

[coolreed]

I have a 14" Shop Fox Band Saw I use for woodworking. There have been times that I was tempted to purchase a replacement blade for cutting metal so I could use it for cutting some angle iron. I asked if this was possible and a salesperson just gasped when I asked if I could cut metal with my bandsaw and stated my warranty would be invalid (as if I ever friggin cared about a warranty).

So I asked around about what is the difference between a bandsaw that cuts wood as opposed to one that cut steel, other than the blade. So far,
no one has been able to explain what exactly is the difference. Stay with me.

Now about a year ago I transferred to a new department at work and in the technician area I noticed they had a 14" Craftsman Band Saw made for woodworking. However, they had a metal cutting blade in it and had been using it to cut metal for years. WTF !!!

So,...the question still remains. What is the big difference between a metal cutting Band Saw and one that is used to cut steel, other than the blade?

(Keeping in mind that I am not talking about some beomuth $20k band saw made expressly for cutting 6" solid steel ingots.)

 

[454ragtop]

It's all about the bass, I mean blade speed. Blade speed needs to be roughly 1/10 of wood speed for steel.
Jim

 

[slip knot]

Yeah, blade speed. most wodworking saws cant turn down slow enough for a metal application.

 

[OccupantRJ]

Speed, blade pitch, and frame rigidity.

 

[Bondo]

Ayuh,.... I think blade speed is the Most important difference,.....

Steel cuttin' needs s l o w speeds, 'n coolant,...

Now Aluminum,....
Wood saws work Great,... just watch out for the chips, 'n keep yer work piece Cold,....

 

[justme-]

#1 is blade speed, but #2 is blade guide. A wood saw blade guide will have at most 1 bearing behind the blade edge (as a thrust bearing) and friction guide blocks "pinching" the blade on the sides for lateral stability. Remember a saw has a guide assembly above the table and another below the table.
Wood cuttings (saw dust) is soft as is most wood in comparison to metal so the torsional forces on the blade are usually less and saw dust collecting on the friction guides is no big deal. Metal chips on the other hand will cause problems on the friction blocks and add friction increasing heat and decreasing blade life. torsional forces are higher adding to that. As such, metal saw guide assemblies have ball bearings instead of friction blocks.
Further difference #3 is wood being soft (in general - yes there are some really hard woods) there is no need for cutting lubricant however you won't find a machine shop out there without it. Metal saws usually have a table and bottom panel design to be friendly to cutting fluid reservoirs or built in ones to collect or properly drain cutting fluid. cutting fluid not only decreases heat on the blade and piece and lubricates the blade and guide bearing interface, but it also helps evacuate chips from the cut.

#4 difference may not be as much today as it was in the past, but the metal saw wheels had a higher rear lip on the to help blade retention. tension on the blade is a factor in metal versus wood cutting - blade tension is essentially the only thing holding a wood blade on the wheels. lighter tension for metal cutting would allow the blade to walk.

Can one be converted to the other - sure if. a quick couple of cuts are not going to kill a saw, and if you have the knowledge and ability one can be modified. My father has an older (20 years old ish) Delta vert/horiz convertible bandsaw that it's previous owner (a machinist) converted. Friction blocks were replaced with a new holder with bearings, a fluid res was made and attached to collect in both positions (with a pump, and assoc parts), and rubber flaps made to "contain" fluid from riding the blade into the housing.
He also made a few other mods like a tank between the legs to hold the fluid and lower mass/center of gravity, redoing pivots to increase accuracy and repeatability...

 

[kctyphoon]

some saws ( i have a 16" grizzly) i belive you might have options on how to wire the motor for blade speed, like a blower motor for a furnace... not 100% if mine does - but can always upgrade guides to full bearings - thats a common upgrade for wood band saws too.. i have them for mine.. also - if you needed - im pretty sure you could always get one of those variable speed switches that they make for router tables and use it with the saw.. or cant you just make your own with a rotary dimmer switch? theres always a way. i wouldnt bother for anything small.. just cut slow, add oil..