Central Machinery bandsaw, should I buy?

BGHansen said:
I was taught that the rule of thumb for teeth per inch is 1 1/2 teeth finer than thickness of material. 1/4" stock is 4 divisions per inch. 1 1/2 times that is 6 so a minimum of 6 tpi for 1/4" stock. Too coarse of a blade and you hammer the teeth of the blade. Depending on what you cut, you may want a variety of tpi. I had as fine as 32 tpi or a spacing of 1/32". Could cut 0.036" sheet metal without much of a problem though I'd liked to have a finer blade.

Bruce
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Dabbler said:
My shop teacher (In the 60s) and my current toolmaker mentor both have told me that you need 3 teeth in contact with the work or you can (will?) lose teeth. FWIW :cautious::apologize:
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Interesting. Not sure why I have this in my head, but I was under the impression that the harder the material the more teeth per inch. So for instance wood or plastic might get say 4 TPI, aluminum and brass 8-10 TPI, and steel may be as many as 32 TPI. Again, not sure of where I got that idea, but it is contrary to what you folks are saying
 
Hi Investigator,
determining blade TPI is not difficult as it may seem.
the idea is for the greatest stock removal for the thickness of the material
a thin piece of material will require a finer pitch, in order to have moore teeth in contact with the work to avoid tearing.
a thicker and wider piece of work can have wider spaced teeth to more easily remove chips that would otherwise clog up the cut

an 8-10 tpi blade may be a good choice for general work in a lot of materials
if you are doing a lot of thin work you'll need a friner pitch
if you are doing 4"x6" work in solid materials, a 4TPI may be better suited for your saw
 
Ulma Doctor said:
an 8-10 tpi blade may be a good choice for general work in a lot of materials
if you are doing a lot of thin work you'll need a friner pitch
if you are doing 4"x6" work in solid materials, a 4TPI may be better suited for your saw
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I'm thinking the largest solid material will be about 2x3, and maybe some 1.5" rounds.
 
I agree with Ulma Doctor; On my saw I run a 14 tooth blade normally, because I mostly do cuts with about 1/4 to 1/2 " cross section. I have a 4/6 variable for cuting larger stuff and it is really worth it to change out the blade, rather than waiting 2 hrs for a 6" round to be cut with the 14tpi.

When I do thin wall tubing I have a 20tpi I had custom made 20 years ago, and only take it out for big jobs. I also set the downfeed to the slowest possible to help prevent the teeth from catching and ripping off. On really thin stuff I put a sacrificial piece of scrap in the cut to help.

BTW do you know about conditioning the blade? there are several good vids on youtube on getting more life out of the blade by conditioning it.

-- I also exclusively dry cut, due to the mess of wet cutting, but I also lightly lube the blade with candle wax, which seems to extend the life a lot.
 
Congratulations with the little bandsaw. I have a similar 4x6 (now a 4x8), and I use it just about every day. I spent a little time initially setting it up, but it just doesn't stay dialed in exactly. That being said it still is a great useful tool in my shop. I replaced the screw that held the cover closed with a threaded T-handle. Its much easier to open and close the blade cover now. The plastic blade tension knob cracked and came off the blade tension screw so I machined a big knurled aluminum knob to replace it that is a light press fit with a set screw for extra security. I find it to be much faster and easier to use than the little plastic knob was. I have used 3 different pitches of Starrett blades, Harbor Freight blades, and the SuperCut blades from Harbor freight. I found the SuperCut blades to be the best value for general cutting. I don't recall the pitch off hand, but HF only offers them in one pitch in the local store anyway.

The little stand of sheet metal legs is cute. I used them initially, but found the low height and need of a stand to be inconvenient for me. I suppose for occasional use they would be fine. It is nice that you can grab the handle and tow it around like a wagon. I took the legs off and threw them in my scrap metal pile after a couple weeks. I mounted some steel extension bars on the end of a roller table and mounted the saw on that. Now I set bar stock on the roller table, and feed it into the saw to be cut off. I don't worry to much about squaring up the saw anymore. I just leave a little extra to be machined off. It saves me a lot of time that way. If I wanted precision square cutting (which I really do) I'd go with a high end slow speed cold cut saw, and mount a micrometer stop on the outfeed. The problem with most slow cut cold saws that I could afford is they won't quite handle the stock sizes I need to cut. Lots of guys brag they have their bandsaws dialed in perfectly, but after spending a couple days playing with it I decided that it wasn't worth the effort to get "pretty close." I square stock up on the mill or on the lathe and I "know" its good.

The big huge fantastic advantage of the bandsaw to me is the ability to break down stock while I am doing other things in the shop. It really is incredible at that. Once you get used to having a horizontal auto shutoff bandsaw. Even a mediocre one like an HF 4x6 you will wonder how you ever got by without one. Speaking of auto shutoff. I wouldn't leave it cutting and go to lunch. You have to keep the chips cleaned off the saw or they can build up and prevent the saw from dropping that last little bit to shut off. Also, if there is any slop in the pivot (doesn't take much) you may want to play with the switch pusher tab to make sure it will turn the saw off every time at all extremes of movement. Even if it seems fine a piece of metal can wedge up with the blade slightly and push the saw over a little more than its normal slop. It can also wedge the blade to a stop with the motor whining. Make sure you approach the saw when its done cutting with care. If its whining or the belt is slipping reach down and push the off switch down with your thumbnail or a screw driver before trying to mess with the stock or the saw. That's probably a good practice anyway. Its possible for the saw to be off, but the switch to not be pushed far enough down to snap over. When you lift the saw it starts back up again.

Its a great tool and you will get thousands of cuts out of it.
 
Got it home, unloaded and tried to use it a bit. Not sure if it had anything to do with the reason for selling, but the blade was on backwards, pointing up.

Also, looks like it needs some adjusting on the rollers. Overall though, looks good. I'm happy so far.
 
Did you get the little table so you can use it as an upright band saw? I do not use mine that way very often, but I do use it. Taking the minute or so to install the table when using the saw in the upright position makes a big difference. Also, there is a pin you can install when using it in the upright position to prevent it from coming down. If you don't have that find one. On my saw it goes in the arm where the spring attaches.
 
Bob La Londe said:
Did you get the little table so you can use it as an upright band saw? I do not use mine that way very often, but I do use it. Taking the minute or so to install the table when using the saw in the upright position makes a big difference. Also, there is a pin you can install when using it in the upright position to prevent it from coming down. If you don't have that find one. On my saw it goes in the arm where the spring attaches.
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No table for upright use. It has a lock tab on the cut off side that levers up and locks against the movable upper section. What does the 'table' look like? Is it something I can fab easily?
 
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