Needs Pictures: 0
Results 1 to 6 of 6
-
10th Apr 2024, 08:45 PM #1Diamond Member
- Join Date
- Sep 2006
- Location
- Australind , WA
- Age
- 58
- Posts
- 1,281
Another Vertical Bandsaw mod to cut Metal
I bought a Carbatec Vertical Bandsaw ( 345C )recently and could not justify the cost I variable speed model as it cost me $1800 as it was.
I am not thinking of modifying it so I can cut differnt metals as well as wood.
My first thought was to use a DC motor and speed control due to DC motors having very good lower speed torque. (They are expensive and would take alot of moding to fit. Also ,none S/H locally )
But then I thought if I could keep the motor speed closer to 50Hz at metal cutting speeds, then a 3 phase motor would have enough torque.
I could do this by fitting a 4 pole 3 phase motor and VFD and then run it at higher frequencies for cutting wood.
With a 2 pole motor, presently the blade speed is 880m/min.
If I fitted a 4 pole 3 phase motor, that would reduce to 440m/min ( still a bit fast?)
So if 440m/min was when running at 50Hz,
Getting back to 880m/min ( not really required, I think ) I would need 100Hz.
300 m/min would be 34 Hz, and
200 m/min would be 22 Hz.
I'm thinking that would probably work OK. 22Hz is not *too* slow, I think. I may not even need to go that slow...not sure yet.
Will try to get a 3 phase 4 pole motor that bolts straight up and get a cheap VFD off Ebay. Shouldn't be too expensive.
Steve
Cutting Speed Calcs.jpg
-
10th Apr 2024, 11:54 PM #2
Have a look a the VFDs on Aliexpress (half price of eBay - around $60 delivered to Australia).
Cheers, Joe
retired - less energy, more time to contemplate projects and more shed time....
-
11th Apr 2024, 11:33 AM #3
I have a 6 pole motor here I plan to use for a large disc sander.
960 rpm same as a Wadkin 30” disc.
These are not easily obtainable like 4 pole but might be worth keeping an eye out for.
H.Jimcracks for the rich and/or wealthy. (aka GKB '88)
-
11th Apr 2024, 12:04 PM #4I break stuff...
- Join Date
- Aug 2010
- Location
- Toorloo Arm, VIC
- Age
- 39
- Posts
- 1,297
If you want to cut anything other than aluminium, you're still going to be running at least 3 times too fast for bimetal at 22hz, and even more so for carbon steel...
https://austechsaw.com.au/documents/Speed%20Chart.pdf
Always the downfall of converting wood saws, you usually need two steps due to the amount of speed change required - in other words, you'd need to combine a pulley swap with your motor change.
-
11th Apr 2024, 02:00 PM #5Diamond Member
- Join Date
- Sep 2006
- Location
- Australind , WA
- Age
- 58
- Posts
- 1,281
-
11th Apr 2024, 03:28 PM #6Diamond Member
- Join Date
- Sep 2006
- Location
- Australind , WA
- Age
- 58
- Posts
- 1,281
I just spotted an obvious mistake on my part.....which makes all this moot.
My motor is already 4 pole, as it spins at 1440 rpm. I'm a bit rusty and the motor doesn't have a name plate.......grrrrr
A 4 pole 3 phase motor won't improve things. I will need more pulley speed reduction than what I have, as mentioned, by others.
Similar Threads
-
Vertical metal cutting bandsaw
By epbrenner in forum WANTED TO BUYReplies: 2Last Post: 31st May 2021, 02:55 PM -
Metal and wood vertical bandsaw?
By Onslo_tas in forum METALWORK GENERALReplies: 7Last Post: 25th Apr 2021, 05:08 AM -
Metal Bandsaw Horizontal Vertical - Hafco RF115 - still in box
By John T K in forum METALWORK - Machinery, Equipment, MARKETReplies: 1Last Post: 20th Apr 2018, 07:16 PM -
Vertical Bandsaw - Convert Wood to Metal ?
By electrosteam in forum METALWORK GENERALReplies: 6Last Post: 13th Dec 2017, 09:03 PM -
Horizontal/Vertical bandsaw
By Stustoys in forum METALWORK GENERALReplies: 12Last Post: 17th Jul 2010, 08:18 PM