In the process of making my 3 wheel bandsaw. I am wanting to use a DC motor of 1 1/2 hp with a speed controller, but would like to add a jack shaft. as well, just to make sure I can keep up the torque on the saw at the necessary speeds needed for general metal cutting. The motor I have is 1 1/2hp Leeson Electric, (removed from a typical treadmill) and runs up to 5120 rpm and pulls 15 amps. The controller I have for it is made by Dart and is supposedly capable of handling up to a 2 HP motor. I understand this controller is supposed to be able to keep the motors torque up at low speeds, but I would not bet my life on it. Guess I am just paranoid, as I do not have to much dealings with DC motors and controllers.
So what ratios would I need to go with to get the saw down to useable speeds for metal cutting? (Looking for 65 to 550 SFPM from what I have found out in regards to speed), although it would be nice to jack it up in speed for wood cutting.
Would I be better off initially reducing the speed with a gear reducer that drives a jackshaft and then the saw or what? Or should I still be able to get by with just a 4:1 ration jackshaft and rely on the speed controller to do its job?
So far except for this problem, the project is going fine. I have one more wheel (drive wheel) yet to cast and machine, shuld have my tires next week, have the caster / camber tension assembly made, starting to work on the blade guides. This brings anopther question to light. Lots of saws today use simple ball bearing for guides. They seem to last ok on my H/V bandsaw, but have a habit of allowing lots of crub get by or get beat into the bearings or blade, so I was thinking on using some guides similar to what DoAll uses. Is there any materials out there that I can machine in a home shop thatw ould serve usefull in making these guides. They need to work with 3/8" at a minimum to no more than a 3/4" blade. Buying those Cool Cut guides is out of the question, so I need to come up with a home brew deal. I was also thinking of using a small engine valve tappet (like found in B & S engines) that runs in a bushing and is adjustable in and out with a setscrew. Any other ideas greatly appreciated.
Presently I have just the basic shape of the frame laid out and am concentrating on making all the actual working parts, so I can juggle things here and there, and the frame will be built around these last.
Looks like it will have a 17" + - 1" throat size, 8 1/2" to 9" cutting height, stand 71" tall, have a width of 29" and be 8 1/2" in depth, take a 107" blade is usiing the three wheels or a 86" blade if utilizing just two wheels. Table size 20 x 22.
The table is still one item that I need to dio a bit of thinking on. I wiuld like to be able to mill it out so I can use a push type rip fence so it looks like a piece of steel plate or perhaps 1/2" thickness is in order, so if anyone has any other suggestions on a table they would also be appreciated. I already have a mitre / rip gauge from a large Delta belt / disk sander that I would like to use. Visit my website: