nine4's projects, restorations and blunders
- Thread starter nine4gmc
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drivesitfar
Well-known member
Don: no i think it wasn't Tampa because he's a pro, but it might have been DLC. or it could have been from my past internet browsing that was of a different learning or viewing experience before GJ? more than likely it was from that damn solitaire game. 
Nines: i know your shop is getting in shape for the new year so any preview pictures while you are slaving away in there?
Nines: i know your shop is getting in shape for the new year so any preview pictures while you are slaving away in there?
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dlcwent
Member Emeritus
Don: no i think it wasn't Tampa because he's a pro, but it might have been DLC. or it could have been from my past internet browsing that was of a different learning or viewing experience before GJ? more than likely it was from that damn solitaire game.
Nines: i know your shop is getting in shape for the new year so any preview pictures while you are slaving away in there?
You got me drives. It was in the e-mail about the big vise. JK, I'm so computer illiterate, I can barely send an e-mail say nothing about a virus.
Nines, what goodies did you get for X-mas, other than cake?
drivesitfar
Well-known member
Nines: you might want to post you cooking skills on here too which looked like you know your way around the kitchen too. hope you had a good Christmas. i really like that the days are going to get longer again now.
DLC: i would never say that you sent a virus on purpose. you are one of the good guys in my book.
not that i have a real book or am keeping track of all the members, but there are a few that are better than others in many respects.
DLC: i would never say that you sent a virus on purpose. you are one of the good guys in my book.
not that i have a real book or am keeping track of all the members, but there are a few that are better than others in many respects.Well it seems good things come in threes, I had a 14" Delta band saw that I did a mechanical resto on and then the 12" Craftsman band saw that I did the complete resto on and now look what I found...
A 20" Delta band saw needing a resto-mod! She's a working 120/240v single phase 1.5hp wood speed machine right now but I will be swapping out the single phase for a 1.5 hp 3ph and adding a VFD for metal and wood cutting. She will get a complete makeover to hide the scars and hard times she's been through. Stay tuned for updates!
A 20" Delta band saw needing a resto-mod! She's a working 120/240v single phase 1.5hp wood speed machine right now but I will be swapping out the single phase for a 1.5 hp 3ph and adding a VFD for metal and wood cutting. She will get a complete makeover to hide the scars and hard times she's been through. Stay tuned for updates!
slodat
ALLIANCE MEMBER
I have one of those! Great machines.
Before and after photo:
Before and after photo:
dlcwent
Member Emeritus
I didn't think I wanted one of those, but I think I'll keep my eyes open. Might be a good addition to the shop.
Slodat, very nice. The grey is killer. And replacing the box with a switch looks a lot better.
Slodat, very nice. The grey is killer. And replacing the box with a switch looks a lot better.
I have one of those! Great machines.
Before and after photo:
Holy smokes! What a beauty!
Awesome!!
Does yours hsve the metal cutting option, did you add a vfd, more info please!
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Nine, amigo, after many discussions on this I would thought it would have been engraved by now. You are going to need more than a VFD to get down into the metal cutting range. If you have a single phase motor right now, just skip the VFD and put the money into a ~40:1 gear box.
Hey Z! Glad you stopped in, would you mind a few questions? The 3ph motor i planned to use is rated at 1735 rpm at 60hz and its rated for 1450 rpm at 50hz, you don't think a vfd would work for me?
The motor on there now is a 1725 rpm 60hz single phase. The motor pulley is 4" diam and the spindle pulley is 7" diam. There is room for a jack shaft and pulleys if i can go that route. Anyone know a good pulley calculator site?
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The motor on there now is a 1725 rpm 60hz single phase. The motor pulley is 4" diam and the spindle pulley is 7" diam. There is room for a jack shaft and pulleys if i can go that route. Anyone know a good pulley calculator site?
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You won't get it slow enough with just a vfd, and if you do you will be so low on the frequency (speed and power) that it won't have much cutting capability. From the factory those run ~4500 sfpm IIRC making it more difficult than converting a smaller saw that run ~3k. You want to be around 125sfpm you need a gear box.
1/2 Cup
Member Emeritus
That bandsaw is a great pick up nines and I am looking forward to seeing your resto mod.
Just a tip using a VFD we are 50 hz out this way and never take a drive below 30 hz. The first one I ever played with I had a brand new motor hooked up to it and was fiddling round with the settings as you do and smoked it running it to lower speed.
Regards
Just a tip using a VFD we are 50 hz out this way and never take a drive below 30 hz. The first one I ever played with I had a brand new motor hooked up to it and was fiddling round with the settings as you do and smoked it running it to lower speed.
Regards
piro222
Member
Nice catch on the 20 incher … boy, those hinges look oogly … I am anxiously awaiting how you handle those ...
You don't really need a pulley calculator … to a first order, the speed reduction (or increase) is directly proportional to the ratio of the pulley diameters … to be more accurate (especially for small diameter pulleys) you would use the ratio of pulley pitch diameter for the belt series you are using (given in a pulley catalog) …
So in your case of a 4” dia drive pulley and a 7” dia wheel pulley, the ratio is 4”/7” which is approximately a 0.571 reduction of speed at the wheel pulley. So if your motor speed is 1725 RPM, your wheel will be running (4/7)*1725 RPM = about 985 RPM. For a more accurate value, the McMaster Catalog lists 6.75” as a pitch diameter for a 7” and 3.75” pitch diameter for a 4” diameter zinc pulley with an “A” section V-belt. In this case, you would clackalate a driven wheel speed of (3.75/6.75)*1725 = approx 958 RPM (about 30RPM or 3% error from using straight pulley diameter).
So your blade speed for the 20” Bandsaw should be 958RPM x 2*pi * radius of the 20” wheel in feet = 958*2*3.1416*10/12 = approximately 5012 fpm … whew, blade really whistling along there …
My “American Machinists Handbook” gives recommended band speeds of 1500-6000 fpm for various non-ferrous metals (like aluminum, brass, or copper) but 50 to 250 fpm for various steel alloys … the harder the steel the slower the saw speed …
So to slow down the saw to be reasonably close to the middle of the steel range, say 150fpm, the driven wheel must run at approximately 28.6 RPM or 30RPM in big round numbers. This requires a 1725/30 which is approx. 58:1 speed reduction. The highest pulley reduction in zinc “A” section drive belt pulley systems, using McM-Carr catalog, would be a 10” to a 1.5” dia system (9.75 to 1.25 inch pitch diameters respectively) which would give you a 9.75/1.25= app. 7.8 to one reduction ratio … doing this twice on a jackshaft might get you 7.8*7.8 = approximately a 60:1 reduction … which might get you in the ballpark.
This is, however, the theoretical discussion … the 1.5 inch dia pulley is awfull small, and center to center distance of the pulleys need to be considered to make sure belt life is acceptable. Also the 1.5” pulley is not offered in a keyway version, and at the 1-2 hp range, I think a keyway would be necessary. In my opinion, I wouldn't use less than a 2 or 2.5 inch dia small pulley, which would result in a 9.75/1.75 = 5.6:1 single reduction for the 2” diameter small pulley (or 31: 1 with double setup and jackshaft – this would give you about a 300 fpm band speed = a bit high, but might work anyway). The 2.5 inch diameter pulley would give a 9.75/2.25 = 4.3:1 (18.5:1 ratio with double setup and jackshaft – gives about 488 fpm band speed).
To get some realism into this, I ran out to the shop to look at my vertical woodcutting bandsaws (I've got three 14 inchers .. a 50's delta, 60's Buffalo, and a Taiwanese knock-off). All three use 1720 RPM motors with a 2.5” and 6” pulley's to reduce the speed and give a theoretical 1720*(2.25/5.75)*2*pi*(7/12) = 2467 fpm or approximately a 2500 fpm band speed …
I have three horizontal 4x6 bandsaws (50's Craftsman, two Taiwan/Chinese knock-offs) and a 7x14 Carolina (US made) … went out and looked at those … all of 'em gotta gearbox, can't tell on the Carolina, as it's buried in the back …
So I went to the DoAll Vertical Metal bandsaw site … they got a bunch of 20 Inchers … looking at a 20x12 inch vertical … it's got band speeds ranging from 30 to 5500 fpm … has a two speed gearbox with 30-320fpm low range and 550-5500fpm high range .. looks like the gearbox mechanically is shifted between ranges and has a continuous adjustment of about 10:1 within the range, probably through an electrically variable speed drive.
I ain't got a whole bunch of experience with variable speed drives yet, but I just bought one for my 3 phase 1hp J-Head Bridgeport, mainly to get into a cheap and easy to use single to three phase converter … a converter more than the variable speed capability … I don't know the useful speed range this will provide the machine … it already has a heap of pulley systems to provide speed variability in the head. I assume that it's a 3 phase induction motor. The other motors I have stashed for other projects are a pile of 1-2.25 hp servo motors with drives from treadmills, these are already single phase motors … I don't know the speed variability available through those drives as I haven't fired up any yet … just waiting their turn in the project cue …
From a practical standpoint, I've been successful in metal cutting non-ferrous stuff (as well as wood) in my verticals and soft (mild) steel in my horizontals without paying any attention to band speed in all these years … I don't know I would want to cut steel in any of my verticals … takes so long with steady pressure to cut through any significant amount of steel, I just rather have the material clamped in the horizontal with the head weight providing the constant pressure, while I do something else worthwhile in the shop …
If I was dead set on making the vertical cut steels, I would think about some combination of the treadmill motors and double pulleys with jackshafts … you might consider the cost also … 2 sets of the zinc pulleys will run about $40 a set for a total of $80 not including the belts, shaft and bearings for the jackshafts … steel pulleys will run whole heaps more … but I think that you can get away with zinc at about 1 hp … if you don't abuse it … I'd also pay attention to the guy down under who has had the experience of smoking a motor by running it at too low a frequency … personally, I don't smoke anything other than salmon or beef or elk jerky ...
The 2012VH DoAll with Hydraulic table (to give a constant feed pressure/feed rate) appeared to be at about $26K new by comparison … whew … don't have enough biz to support that cost ...
Good luck on the project ...
… boy, those hinges look oogly … I am anxiously awaiting how you handle those ...You don't really need a pulley calculator … to a first order, the speed reduction (or increase) is directly proportional to the ratio of the pulley diameters … to be more accurate (especially for small diameter pulleys) you would use the ratio of pulley pitch diameter for the belt series you are using (given in a pulley catalog) …
So in your case of a 4” dia drive pulley and a 7” dia wheel pulley, the ratio is 4”/7” which is approximately a 0.571 reduction of speed at the wheel pulley. So if your motor speed is 1725 RPM, your wheel will be running (4/7)*1725 RPM = about 985 RPM. For a more accurate value, the McMaster Catalog lists 6.75” as a pitch diameter for a 7” and 3.75” pitch diameter for a 4” diameter zinc pulley with an “A” section V-belt. In this case, you would clackalate a driven wheel speed of (3.75/6.75)*1725 = approx 958 RPM (about 30RPM or 3% error from using straight pulley diameter).
So your blade speed for the 20” Bandsaw should be 958RPM x 2*pi * radius of the 20” wheel in feet = 958*2*3.1416*10/12 = approximately 5012 fpm … whew, blade really whistling along there …
My “American Machinists Handbook” gives recommended band speeds of 1500-6000 fpm for various non-ferrous metals (like aluminum, brass, or copper) but 50 to 250 fpm for various steel alloys … the harder the steel the slower the saw speed …
So to slow down the saw to be reasonably close to the middle of the steel range, say 150fpm, the driven wheel must run at approximately 28.6 RPM or 30RPM in big round numbers. This requires a 1725/30 which is approx. 58:1 speed reduction. The highest pulley reduction in zinc “A” section drive belt pulley systems, using McM-Carr catalog, would be a 10” to a 1.5” dia system (9.75 to 1.25 inch pitch diameters respectively) which would give you a 9.75/1.25= app. 7.8 to one reduction ratio … doing this twice on a jackshaft might get you 7.8*7.8 = approximately a 60:1 reduction … which might get you in the ballpark.
This is, however, the theoretical discussion … the 1.5 inch dia pulley is awfull small, and center to center distance of the pulleys need to be considered to make sure belt life is acceptable. Also the 1.5” pulley is not offered in a keyway version, and at the 1-2 hp range, I think a keyway would be necessary. In my opinion, I wouldn't use less than a 2 or 2.5 inch dia small pulley, which would result in a 9.75/1.75 = 5.6:1 single reduction for the 2” diameter small pulley (or 31: 1 with double setup and jackshaft – this would give you about a 300 fpm band speed = a bit high, but might work anyway). The 2.5 inch diameter pulley would give a 9.75/2.25 = 4.3:1 (18.5:1 ratio with double setup and jackshaft – gives about 488 fpm band speed).
To get some realism into this, I ran out to the shop to look at my vertical woodcutting bandsaws (I've got three 14 inchers .. a 50's delta, 60's Buffalo, and a Taiwanese knock-off). All three use 1720 RPM motors with a 2.5” and 6” pulley's to reduce the speed and give a theoretical 1720*(2.25/5.75)*2*pi*(7/12) = 2467 fpm or approximately a 2500 fpm band speed …
I have three horizontal 4x6 bandsaws (50's Craftsman, two Taiwan/Chinese knock-offs) and a 7x14 Carolina (US made) … went out and looked at those … all of 'em gotta gearbox, can't tell on the Carolina, as it's buried in the back …
So I went to the DoAll Vertical Metal bandsaw site … they got a bunch of 20 Inchers … looking at a 20x12 inch vertical … it's got band speeds ranging from 30 to 5500 fpm … has a two speed gearbox with 30-320fpm low range and 550-5500fpm high range .. looks like the gearbox mechanically is shifted between ranges and has a continuous adjustment of about 10:1 within the range, probably through an electrically variable speed drive.
I ain't got a whole bunch of experience with variable speed drives yet, but I just bought one for my 3 phase 1hp J-Head Bridgeport, mainly to get into a cheap and easy to use single to three phase converter … a converter more than the variable speed capability … I don't know the useful speed range this will provide the machine … it already has a heap of pulley systems to provide speed variability in the head. I assume that it's a 3 phase induction motor. The other motors I have stashed for other projects are a pile of 1-2.25 hp servo motors with drives from treadmills, these are already single phase motors … I don't know the speed variability available through those drives as I haven't fired up any yet … just waiting their turn in the project cue …
From a practical standpoint, I've been successful in metal cutting non-ferrous stuff (as well as wood) in my verticals and soft (mild) steel in my horizontals without paying any attention to band speed in all these years … I don't know I would want to cut steel in any of my verticals … takes so long with steady pressure to cut through any significant amount of steel, I just rather have the material clamped in the horizontal with the head weight providing the constant pressure, while I do something else worthwhile in the shop …
If I was dead set on making the vertical cut steels, I would think about some combination of the treadmill motors and double pulleys with jackshafts … you might consider the cost also … 2 sets of the zinc pulleys will run about $40 a set for a total of $80 not including the belts, shaft and bearings for the jackshafts … steel pulleys will run whole heaps more … but I think that you can get away with zinc at about 1 hp … if you don't abuse it … I'd also pay attention to the guy down under who has had the experience of smoking a motor by running it at too low a frequency … personally, I don't smoke anything other than salmon or beef or elk jerky ...
The 2012VH DoAll with Hydraulic table (to give a constant feed pressure/feed rate) appeared to be at about $26K new by comparison … whew … don't have enough biz to support that cost ...
Good luck on the project ...
Hey Piro, that puts it into perspective, thanks! One thing to mention, I'm not wanting to cut thick metal, I have a plasma cutter and other methods for that. I'm looking to cut seat brackets and frames etc, mostly 1/8" or less thickness. Also, things like 12-20ga sheet metal. I have a 14" Delta Milawaukee with the gearbox on it to slow it down for metal cutting and figured I could slow this 20" down as well. I guess it will be more of a challenge than I imagined but game on, there has to be a cheap alternative like a gear box from a scooter or lawn tractor that I can fab up to work. The base is plenty big enough for lots of ideas. I have a lathe and can make some parts if necessary.
One thing I do know, the speed is too fast as-is since the motor and motor pulley are not factory. As you said the speed is over 5k fpm, owners manual states a 3.5" pulley(I measured 10x mine is 4") is 4500 fpm. I have several treadmill motors, a couple 3ph motors and this 120/240v A.O. Smith motor. Maybe I could mod the gas scooter or tractor engine/trans in there and have a monster gas powered band saw.
No I keed, I keed...
Here is a pic of my 14" Delta, I did a mechanical resto on it changing bearings and tires and polishing up various parts. This pic was taken today, it gets used often, mostly on metal. I'll try to get a pic of them together later, the 20" is comically huge...
One thing I do know, the speed is too fast as-is since the motor and motor pulley are not factory. As you said the speed is over 5k fpm, owners manual states a 3.5" pulley(I measured 10x mine is 4") is 4500 fpm. I have several treadmill motors, a couple 3ph motors and this 120/240v A.O. Smith motor. Maybe I could mod the gas scooter or tractor engine/trans in there and have a monster gas powered band saw.
No I keed, I keed...Here is a pic of my 14" Delta, I did a mechanical resto on it changing bearings and tires and polishing up various parts. This pic was taken today, it gets used often, mostly on metal. I'll try to get a pic of them together later, the 20" is comically huge...
McBrownie
Well-known member
Maybe I could mod the gas scooter or tractor engine/trans in there and have a monster gas powered band saw.
Nines,
Many years ago, in my IT career, I worked for a company where the headquarters caught on fire. The main computer server survived the fire and fire hoses. I had to hook it up to generator. I think it was the only pull-start HP9000 in existence. That was a great machine and even better when I had to make sure there was gas in the tank.
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piro222
Member
I'm probably in violent agreement that a gearbox is the way to go. I'd like to see what kind of gearbox could be scared up for cheap ... I like the scooter/garden tractor/lawnmower ideas for gearboxes ... I know you just keeding, but I've discovered that the fewer gas powered engines I have, the less time I spend messing around with getting **** around here to run (excepting recent Honda, Husquarna and maybe Stihl ...).
My 14" Delta is in the process of restoration ... still sitting in cue behind the Farmall 100, 72 Chev PU, and Aristocrat Loliner .... and a seriously organization challenged shop ...
Looking forward to how this turns out ...
My 14" Delta is in the process of restoration ... still sitting in cue behind the Farmall 100, 72 Chev PU, and Aristocrat Loliner .... and a seriously organization challenged shop ...
Looking forward to how this turns out ...
I was actually keeding about the gas engine part, I would love to scrounge up a gear box from something being scrapped and make it work. My old shop just had a scooter warehouse burn up and there are lots of scooters there, along with a few riding lawmowers and a zero turn. I haven't messed with many so I don't know where to start but there has to be something out there with a gear box that could work.
Thanks for your posts Piro!
That's funny McB!
ZK, I'm not opposed to using a gear reducer box but the way Piro explained it I would need two gear reducers inline with the motor and I think that would loose too much efficiency. I'm also not to fond of the price of new gear reducers so I would need to find a single used gear reducer or some sort of transmission from something I can get cheap for parts(like a lawnmower or scooter with smoke damage )
Thanks for your posts Piro!
That's funny McB!
ZK, I'm not opposed to using a gear reducer box but the way Piro explained it I would need two gear reducers inline with the motor and I think that would loose too much efficiency. I'm also not to fond of the price of new gear reducers so I would need to find a single used gear reducer or some sort of transmission from something I can get cheap for parts(like a lawnmower or scooter with smoke damage
)No you don't, he just made a long winded post that goes in circles without saying much of value. Do you as you like.
Trust me on this, the makers of successful metal cutting bandsaws from the ~40's on up, almost all of which used a gear box , know much more than anyone on this forum. It's a practicality issue of asking too much from a belt reduction system which are typically limited to ~7:1.
Pulleys, belts, shafts, bearings all add up quick. There are tons of low HP 30:1,40:1 and similar boxes out there that can be had for under $100 used.
Trust me on this, the makers of successful metal cutting bandsaws from the ~40's on up, almost all of which used a gear box , know much more than anyone on this forum. It's a practicality issue of asking too much from a belt reduction system which are typically limited to ~7:1.
Pulleys, belts, shafts, bearings all add up quick. There are tons of low HP 30:1,40:1 and similar boxes out there that can be had for under $100 used.
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Gizmosity
Well-known member
I've had a couple of these through the years and I'm looking to get one again. One I used many years ago was dual speed. A gearbox was an option in these. Long shot, but you might do a bit of research on that gearbox and see what comes up.
Outlawmws
Well-known member
With all due respect to ZK:
One jack shaft, two pillow blocks, two pulleys, and a treadmill motor, and you will have near infinite speed options and you can't hardly stop a treadmill motor at any speed.
Not "all" band saw MFG's used gear boxes either.
One jack shaft, two pillow blocks, two pulleys, and a treadmill motor, and you will have near infinite speed options and you can't hardly stop a treadmill motor at any speed.
Not "all" band saw MFG's used gear boxes either.
I already have a jack shaft and several pillow blocks and pulleys of all sizes. I need to brush up on my math skills but ive been using an online pulley speed calculator and a sfpm calculator on the vintage machinery website and cant even get close to 200 sfpm.
I think two jackshafts or two gearboxes are out of the question due to system loss.
There is a Baldor 60:1 gear reducer on ebay right now for about $100, thats looking like an option if i read right.
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I think two jackshafts or two gearboxes are out of the question due to system loss.
There is a Baldor 60:1 gear reducer on ebay right now for about $100, thats looking like an option if i read right.
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Outlawmws
Well-known member
Nines, what size is the drive wheel for the blade, and the pulley on it?
Therobdog, i primarily use rustoleum but the Craftsman band saw was done with Hammertite that i got from a garage sale.
Outlaw, the drive wheel is 20" and the pulley is 7" on it. The motor has a 4" pulley.
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Outlaw, the drive wheel is 20" and the pulley is 7" on it. The motor has a 4" pulley.
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The factory gear box option is integrated into the lower wheel to be driven from the output of the gearbox to the lower frame/wheel. Another problem with converting a saw is getting all the (now multiplied) torque transferred from the gear box to the lower wheel. Belts are not good at low speed high torque transfer applications.
Not trying to be a Debby downer or know it all on the band saw conversions, but I have been through this over the years and have learned what works and was does not. I've gotten to the point in my life where I have a hard time tolerating cobbled together, make shift tools.
Converting a 9 or 10" bandsaw with belts and special motor is fine and cute, 14" is borderline, but once you get into 18"+ saws you are really doing the saw a disservice by using a non optimal drive system. Honestly I might just recommend Nine to leave the 20" as a wood/plastics saw and keep his proper 14" w/m saw as a dedicated metal saw. If all he is doing is sheet metal up to ~1/2" there won't be much of a performance difference. The biggest drawback to the 14" and even the 20" is the table truninos just can't take the weight of a good sized chunk of steel. As nice as the 20" delta is, it is still a pretty light duty saw compared to a true commercial vertical metal saw (I have 2 14" w/m, 1 14" wood and 1 20" delta w/m saws now).
You need ONE gear box and an overall reduction of ~70:1 between the 1725rpm motor and the driven wheel shaft. The way the delta W/M version VS version accomplishes the variable speed part is through a CVT reeves setup. Nice, but not necessary.
If you are serious about this, I would start searching for a gear motor 1/2hp minimum with a ~100 RPM output. That would be your most compact solution.
On the smaller saws that can be OK, but once you get into the larger saws that can tolerate higher blade forces and larger wheels it becomes problematic, primary due to belt slip. Or you end up with an entire line shaft shop below your bandsaw.
I can't think of one commercially made, true metal cutting vertical saw that does not use a gear box reduction. There is a reason the designers use a gear box, it is the most practical solution. Lets take the ubiquitous 4x6 horizontal saws for example. We know they build those as cheap as possible and even they know it is best to use a gear box for the high reduction.
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slodat
ALLIANCE MEMBER
I had a Powermatic 20" metal cutting vertical bandsaw. It has a two speed gearbox and a reeves drive. Great saw. Would like to find another!
That would be fine, but so would anything in a ~20:1-70:1 range. Again your overall reduction from the output of the 1725RPM motor to the input of the drive wheel needs to be ~70:1, The smaller the changes with the belts the better, especially on the backside of the gearbox going into the drive wheel as that is where the most torque is going to be, may want to consider a toothed belt or even a sprocket system. Remember gear reductions multiply like fractions. So say you have a 2:1 between the motor and the input of the gear box, a gear box at 30:1 and then a output of the gear box to driven wheel in the 1.2:1 range, you have met your ~70:1 goal.
Outlawmws
Well-known member
Nine, your ratio issues is primarily that 7" pulley and the 4" on the motor. One or the other needs to change, better if both did.
Belt slippage can be an issue, but can also be dealt with on the primary drive (the only real place it would be a real issue) Anything beyond that primary drive should not be a problem as the gearing factors are on your side.
To get anywhere near what you need on the SFPM and assuming a 1725 RPM motor with the Jack shaft you need a 10" and 2", and the 2" could be an issue from a slippage point of view. (probably why they used a 4" on the motor from the factory)
If you can get a suitable gear reduction at a reasonable cost, then it can get easier; my experience is that gear drives are pricey.
What gear reduction you need will be driven by both what pulleys you put on it, and what is on both the motor and the drive wheel. using a 4" on the input and a 7 on the output (for 1:1 on those drives) on a 50:1 gearbox puts you below 200 SFPM @ a 1725 RPM motor. (181 to be exact)
ZK, assuming the same 4" drive pulley, and the same 7" driven pulley that 100 RPM gear motor lands at 299 SFPM, no? Did I misread you guys were aiming for 200?
The suggestion to keep the smaller metal cutter for metal, and this one for wood/foam is probably the most practical except from a shop space perspective.
Belt slippage can be an issue, but can also be dealt with on the primary drive (the only real place it would be a real issue) Anything beyond that primary drive should not be a problem as the gearing factors are on your side.
To get anywhere near what you need on the SFPM and assuming a 1725 RPM motor with the Jack shaft you need a 10" and 2", and the 2" could be an issue from a slippage point of view. (probably why they used a 4" on the motor from the factory)
If you can get a suitable gear reduction at a reasonable cost, then it can get easier; my experience is that gear drives are pricey.
What gear reduction you need will be driven by both what pulleys you put on it, and what is on both the motor and the drive wheel. using a 4" on the input and a 7 on the output (for 1:1 on those drives) on a 50:1 gearbox puts you below 200 SFPM @ a 1725 RPM motor. (181 to be exact)
ZK, assuming the same 4" drive pulley, and the same 7" driven pulley that 100 RPM gear motor lands at 299 SFPM, no? Did I misread you guys were aiming for 200?
The suggestion to keep the smaller metal cutter for metal, and this one for wood/foam is probably the most practical except from a shop space perspective.
piro222
Member
NineFour:
I'm just being your pulley calculator here:
For "A" and "B" section V belt pulleys, 1725 RPM drive motor, and 20 Inch Bandsaw Drive Wheel:
a 2.5" motor pulley with an 8" pulley on Bandwheel will give you 2622 fpm
a 2.5" motor pulley with a 9" pulley on Bandwheel will give you 2323 fpm
a 3" motor pulley with a 10" pulley on Bandwheel will give you 2547 fpm
All else equal, I would go with the largest motor pulley (3"), but all my factory 14 inch saws run with 2.5" pulleys quite well on 3/4 hp motors ...
I think this gets you in the ball park ... if you want other ratios, let me know and I will crank em out for ya ...
I'm just being your pulley calculator here:
For "A" and "B" section V belt pulleys, 1725 RPM drive motor, and 20 Inch Bandsaw Drive Wheel:
a 2.5" motor pulley with an 8" pulley on Bandwheel will give you 2622 fpm
a 2.5" motor pulley with a 9" pulley on Bandwheel will give you 2323 fpm
a 3" motor pulley with a 10" pulley on Bandwheel will give you 2547 fpm
All else equal, I would go with the largest motor pulley (3"), but all my factory 14 inch saws run with 2.5" pulleys quite well on 3/4 hp motors ...
I think this gets you in the ball park ... if you want other ratios, let me know and I will crank em out for ya ...
Outlawmws
Well-known member
Is that a factory motor or pulley? Maybe it was designed for a motor @ 1150 or so? or possibly a multi speed motor? (I have a motor that has 4 wired speeds, but was probably designed for a big blower or fan...)
IDK if I can get a 9 or 10" bandwheel pulley on there due to the way it is setup but I'll have to measure.
The owners manual does recommend this speed motor but with a 3.5" pulley, this motor and pulley are NOT factory. I can tell it was added later, this was most likely a 3ph machine in a school or city work shop(it has state property tags like all my other auction items). Here is a quote from the manual:
Yes, or 3800 depending the motor option used.