Converting bandsaw from wood to metal/wood

[bjmh46]

You really need at least a 10 or 15:1 hard reduction--you're looking for 100-150 sfpm for steel, 500-1000 for non-ferrous (brass and aluminum), 3000-3500 for wood and some plastics. Cutting wood and metal on the same saw has never been a problem for me, I've been doing it on the same saw for 33 years. The 20 inch DoAll we had at work cut everything from Steel plate to 6 x 8 wood skids and never missed a beat. A little sensible housekeeping is in order, but not a problem. A bandsaw is a machine that, in order to get the most out of it, you have got to change blades. Best thing is to develop some facility in doing it, even if it means modifying the guides to make it easier to change blade size. A vertical contour band machine is a wondrous thing, I couldn't imagine having a shop without one.

So, get yourself a 10 or 15:1 gearbox, and devise a drive--you'll love the capability.

Bob

 

[GaryK]

Thanks for all your comments, but I just bought a dedicated metal cutting bandsaw. Seemed like more trouble that it was worth.
Thanks again.


Gary

 

[iron man]

I just did this conversion I got a 14 inch jet bandsaw really cheap I built a small jack shaft and geared it down but it was still to fast. But then a friend of mine come over with a 2 1/2 horse dc treadmill motor with a PWM variable speed control which gives you full power or full voltage through out the range. I have the best of both worlds with just a turn of a dial it works and looks great. Ray

 

[rdhem2]

What speeds did you use for the METAL High-Low?

In feet per minute I can not answer. I got the local bandsaw blade sales guy to come over and we we set the speeds by look, feel, and reaction of several types of materials. Roughly set by reading the cycles screen on the VFD.
High Speed Wood-60hz Delta factory wood speed.
Low Speed Wood-49hz
High Speed Metal-30hz
Low Speed Metal-23hz

That is the beauty of a VFD.
Greatest thing since sliced bread.

Blade life is great. :drinkingbeer:

 

[AlanR]

I have a PM 143 which is a metal cutting BS that has a high and low speed more so for the thickness of the metal,so a VFD would be perfect but.I would think that mixing wood and metal on one BS would contaminate the wood w/metal shavings.Not good--Kroll

You can pick up inexpensive wood bandsaws for cheap on craigslist, I've got one that was given to me that I'm not using. They don't hold up - then trash them.

I've got 3 phase motors kicking around, I might do this, how about 5 HP?

 

[OrangeAlpine]

You can pick up inexpensive wood bandsaws for cheap on craigslist, I've got one that was given to me that I'm not using. They don't hold up - then trash them.

I've got 3 phase motors kicking around, I might do this, how about 5 HP?

I've operated my bandsaw with as little as .5 hp, so I guess 5 hp would work. As they say, there is no kill like overkill.

Bill

 

[rdhem2]

I have a PM 143 which is a metal cutting BS that has a high and low speed more so for the thickness of the metal,so a VFD would be perfect but.I would think that mixing wood and metal on one BS would contaminate the wood w/metal shavings.Not good--Kroll

Mr. Kroll;

Pls explain why I would care if my wood shavings were contaminated with metal---or vise versa.
Man, I am lost on this one. :thinking:

 

[hman]

Mr. Kroll;

Pls explain why I would care if my wood shavings were contaminated with metal---or vise versa.
Man, I am lost on this one. :thinking:

There are two issues here.

First off, if your blade is crudded up with metal shavings, especially aluminum, the shavings would embed themselves in the cut surface and deposit on the top surface of the wood. Any blade lubricant would transfer, too. Depending on your proposed finishing steps, and how "pretty" the wood piece is supposed to be, this could become a headache.

Second is be the possibility of dropping hot metal (especially steel) chips and/or sparks into the deposits of wood sawdust below the table. Could lead to smoldering, maybe even a fire. I'm not sure how common this is, but I have heard it mentioned as a general caution on working wood and metal with the same tool.

I have a wood-cutting bandsaw (the green Taiwan-manufactured Harbor Freight special), and have been considering a conversion - but hesitated for several reasons, including the cross-contamination issues. If I do decide to go ahead, I'll probably use the "hillbilly jack shaft" method - install a second motor with a small diameter pulley, run a belt to the largest pulley on the original motor, run the saw from the smallest pulley on the original motor. Using the original motor as a "hillbilly jack shaft" obviously requires that you only power up one motor at a time!!! And when not using the second motor, remove the belt.

- John
(hman)

 

[bjmh46]

There are two issues here.

First off, if your blade is crudded up with metal shavings, especially aluminum, the shavings would embed themselves in the cut surface and deposit on the top surface of the wood. Any blade lubricant would transfer, too. Depending on your proposed finishing steps, and how "pretty" the wood piece is supposed to be, this could become a headache.

Second is be the possibility of dropping hot metal (especially steel) chips and/or sparks into the deposits of wood sawdust below the table. Could lead to smoldering, maybe even a fire. I'm not sure how common this is, but I have heard it mentioned as a general caution on working wood and metal with the same tool.

I have a wood-cutting bandsaw (the green Taiwan-manufactured Harbor Freight special), and have been considering a conversion - but hesitated for several reasons, including the cross-contamination issues. If I do decide to go ahead, I'll probably use the "hillbilly jack shaft" method - install a second motor with a small diameter pulley, run a belt to the largest pulley on the original motor, run the saw from the smallest pulley on the original motor. Using the original motor as a "hillbilly jack shaft" obviously requires that you only power up one motor at a time!!! And when not using the second motor, remove the belt.

- John
(hman)

--Nobody who is serious about wood working is going to cut with a metal cutting blade that has been used for metal. I repeat myself, but a bandsaw will serve you best if you are willing to change to the appropriate blade for the job.

--First off. I've never had a spark sawing metal at regular metalcutting speeds. Friction sawing is another story--did I mention housekeeping?
Bob

 

[Fabrickator]

I've used an import 14" band saw for cutting wood & metal for many years now. I added a 6" riser block in the backbone to cut up to 12" logs with it for bowl turning blanks and slicing off veneer board strips. I run a 1 HP motor at 1750 RPM and it has more than enough power to cut a 12" log in two, or a 1" thick block of steel. I reduced the std. speed by about half by a simple pulley change and it worked well for aluminum and wood, but still too fast for steel. I reduced the speed by half again with a jack shaft and now it cuts at 75 FPM which is ideal for steel but slow for aluminum and wood. I can live with slow for cutting aluminum and the occasional wood because I don't work in a production environment and have plenty of time.

All you have to do is be sure that you're using the correct blade for the material that you're cutting and practice good housekeeping when changing from wood to steel, non-ferrous metals & wood are OK together.

I keep an assortment of blades for wood and metal in multiple sizes (1/8", 5/16", 3/8", 1/2" and a 3/4" wood rip blade). If you use them correctly at the right speed and don't force them (overheat), they almost last forever. Remember, if the part being cut is so hot that a wood pusher block is starting to smell burnt, the blade won't be much farther behind it. Narrow blades heat up quicker and burn up faster. They also dissipate heat faster, so stop and let it cool for a few minutes.

Rick