Silver Mfg 32" Bandsaw

[CHIZZLER]

Here is my recent Cl find. Early 1900's saw. It's a wood cutter now. Looking to convert to metal cutting. Is there a formula to figure out Feet per minute and what gear reduction I may need? Currently it has a 2hp motor spinning at 1705. It's 3ph so i can't run it. Thanks for any help. CHIZZLER

[mongocanfly]

Chizzler.. if my "rusty math" still works for metal you will need about 50 sfpm for steel and 100 sfpm for aluminum..ours at work is a variable speed saw. Assuming your silver saw has the 26" wheels and if you run a 1750 rpm motor you will need approx 116 to 1 ratio to get 15 rpm which should then be 100 sfpm... and 250 to1 ratio to get 7 rpm which should get you 50 sfpm. i may be wrong but it should be close..even your 1705 rpm motor wouldn't be much different on the ratios to get about the same sfpm

1750 rpm -116.1 ratio- 15 rpm- 100 sfpm
1750 rpm -250.1 ratio- 7 rpm -50 sfpm

[Advanced Design]

I will defer to all others on the math...that is a cool CL find though Chizzler!

[CHIZZLER]

Thanks for the info Mongo. Here is a pretty cool website that has a sfpm calculator.

www.vintagemachinery.org/math/sfpm.aspx

My machine comes out to 4508 sfpm. If ideal for metal cutting is about 65 sfpm then divide the numbers and it's 69:1 gear reduction.

[mongocanfly]

Chizzler that is a good site you found...I assume that 69:1 is in addition to the reduction your saw already has..good find though

[CHIZZLER]

My setup is 6" pulley on motor, 19" pulley on saw, 32" wheels.

[mongocanfly]

32" wheels...wow...i just caught you were dividing sfpm by sfpm to get 69:1..thats not going to be the same as getting the rpm you need to slow it down..by my ciphering you need those big ol wheels turning about 8 rpm to get 65 sfpm..gonna need a lot of reducing to get it that slow.i still come up with around 200 to 250:1 ratio from motor to wheel to get it down that slow.. here's the one I used.http://www.ollivier.nl/html/SFM-RPM-calculator.htm

[BR3W CITY]

Thats rad

[CHIZZLER]

Thanks mongo for the help. This is not my area of expertise at all. Im looking for a motor and gear reduction locally but nothing right now.

[dwcsr]

Wow, you get tangled up in that and your a pretzel. Cool saw for sure

[mongocanfly]

Chizzler here is a place I've bought a lot of stuff from over the years...surplus center... might give you some ideas

[mongocanfly]

They have a 1 1/2hp motor (10-2538a) that runs 1730 rpm...they have a 60:1ratio gearbox (13-325-60) as well...if you dropped that 6" pulley down to a 5" that should give you a final drive rpm of about 7.5 rpm..
1730÷60=28.8 rpm....28.8 rpm÷ 3.8=7.57 rpm.....19" pulley÷ 5" pulley to get 3.8 reduction..all that adds up to about 7.57..
7.57 final rpm and a 32" band wheel will give you 63 sfpm.. with all the reduction you need a 1 1/2hp motor should be plenty I think. And PLEASE don't use that saw until you build some guards for it..like dwcsr says that thing would wrap you up in it if something happened.

[mongocanfly]

Sorry..I thought this link went in the other post..http://www.surpluscenter.com/

[CHIZZLER]

Thank you for the info mongo. You have been very helpful. I did view both parts on there website. I would need a 5" double pulley to mount to the gear reduction. They list the shaft on the gear reduction as a hollow shaft but no size. There is nothing local for sale at this time. Thank you again.

[mongocanfly]

Hmm ...I don't see it listed as a hollow shaft..its 1 3/8" output shaft..here's the specs.SPECIFICATIONS..Ratio*60:1Power*2.03 HP max.Input Speed*1725 RPM max.Output Speed*29 RPM max.Output Torque*3127 in-lb. max.Output Centerline Height*3.5"Overhung Load*882 lbs.Input Shaft*7/8" dia. x 2-7/16" keyedOutput Type*Left hand shaftOutput Shaft*1-3/8" dia. x 3-1/4" keyedMount*7-1/2" x 4" centersSize*10-7/16" x 7-13/16" x 9-3/8"Shpg.*82 lbs....gearbox item number 13-325-60 L or R

[CHIZZLER]

I see the one you specd. I figured the gear reduction would slide over the shaft of the motor.

[mongocanfly]

Just looking at the picture it looks like the keyed shaft just sticks out ,not over the motor shaft..meaning it would need a coupler between motor and gearbox...we use these style boxes at work and that's the way they are. Its not a cheap endeavor to do all that reducing but you would have one heck of a saw when you get it setup.

[CHIZZLER]

I do see they offer A 7/8" keyed coupler for pretty cheap. Again Thanks for your help and time. I will Post when I have come up with something.

[CHIZZLER]

I think this is what you are suggesting mongo.

http://www.surpluscenter.com/shop.axd/Cart

[CHIZZLER]

Quick update. Scored A massive 60:1 renold gear reduction off my local CL for $60. I had a local machine shop make A shaft to slip inside the gear box and accept the new pulley. Got A metric new 2HP take off motor from Ebay. Today we Hooked the gear reduction and motor together and used a Adjustable sliding base plate that the band saw came with. Earlier this week I had some time and made a all steel pallet to mount everything to. Finally it's getting closet to having this thing come alive. Thanks Mongocanfly for the help.

[Advanced Design]

That gear reduction was a nice score. Are you making chips yet?