Reviving a back burner project

The Math -- :lmao: -- Motor turns 1750 RPM. Reduces to 29 RPM thru reduction unit. Blade is approximately 8 feet. wheels are 14 inches in diameter. I get 116 FPM for speed of blade. Thats slow. I'll have to pick up at least another 120 FPM. Translates to 2:1. 29 RPM at the reduction unit to 58 RPM at the driven blade wheel ?

Am I right here or is it late and I'm tired and got it wrong?


"Billy G" :))
 
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That's what I thinking when I saw the 60:1. You could use a larger pulley on the motor to double (or whatever) the speed.

I like the hardware you made up for the saw. Very nice.
 
I am looking to get aproximately 250 FPM Shawn. The same speed as I have on my Horizontal saw. It works best as far as I can see.

"Billy G"
 
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shawn said:
I just picked up an old bandsaw on Craigslist and was thinking about doing something similar. I have a 60:1 reduction drive, what would be the ideal fpm speed I would be looking to achieve?
Click to expand...

Shawn,

The cutting speed depends on the material you want to saw. The 250 SFPM number that Bill is shooting for is perfect for aluminum and brass, but if you want to cut mild steel, it should be in the 125 SFPM range and tool steel or stainless should be around 80 SFPM. Many saws have a back gear to create two speed ranges and then step pulleys for minor adjustments in each range.

Tom
 
This will be the set-up for now. Motor side of the reduction unit will be 1:1 Outlet side of the reduction unit is 60:1. Now on the reduction output side witll be a 10 inch pulley. On the driven blade wheel will be a 4 inch pulley. This will yield 266 SFPM. If I replace the 10 with a 9 it will yield 236 SFPM.

"Billy G" :thinking:

I used this link

http://vintagemachinery.org/math/sfpm.aspx
 
New game plan. :lmao: I'm gonna turn two multiple sheeves. The one on the blade wheel will be 4-4-4. The one on the reduction unit will be 10-6-3. Speeds will be 266-159-80 SFPM. This gets better all the time. I will use the same belt for all speeds with the addition of an idler pulley to catch the slack.

"Billy G" :hi:
 
Rounding third base and headed for home. The drive is all that is left. I am driving the reduction unit now and have to drive the blade wheel yet.

"Billy G" :thinking:

rthh 001 (750 x 563).jpg rthh 003 (750 x 563).jpg rthh 002 (750 x 563).jpg
 
First thing I saw when looking at your pictures was this face looking back at me.


face.jpg




Project looks good! I need to do some work on mine as well.

face.jpg
 
Redoing the math using the link below got us in the ballpark.

Reduction RPM = 28.7

Reduction Pulley (Motor Pulley) = 6 inches

Wheel Pulley = 2.5 inches

Wheel Dia. = 14 inches

Calculated SFPM = 255

I need to get the 6 inch pulley and a 47 inch belt and this project is complete.

http://vintagemachinery.org/math/sfpm.aspx

"Billy G"


I never would have noticed that little guy if you hadn't pointed him out. Thanx.
 
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This project is finished. We went for 250 SFPM. Calculations said 255 SFPM. Real world ended up at 248 SFPM. Done deal.

I will post the last pics a little later.

"Billy G" :thumbsup:
 
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