I am acquiring a G4 (B I think) that has a 3 phase motor.
I want to swop out the motor for a single phase motor. Is there a particular motor that is recommended?
I am also concerned about mounting. Is there anything to know about mounting and pulley size?
Alternately, is there any reason not to purchase a 3 phase converter instead?
I will be using this saw to cut maple blocks for making wooden printing type.
Glider G4 3 phase to single phase
Moderator: crzypete
Hi Bill,
Welcome to the forum.
There are two options that you have presented. Option one involves modifying the saw, option two involves modifying your electrical supply.
Knowing more about how you will want to use it helps decide which is the correct direction to go in.
If you told me you would be buying more 3Ø equipment, I would recommend a rotary phase converter. You can make these in house or buy a ready made one.
If you are going to have employees or turn it off and on very frequently, I would advise to take the time to convert it to a single phase machine.
For less effort, you can make 3Ø power with a VFD, Variable Frequency Drive. This is probably a pretty good option. There is much on the internet about VFD's, Id recommend the VFD section at practical machinist for advice on this subject, they are really into their electric http://www.practicalmachinist.com/vb/tr ... rters-vfd/
Static converters are cheap, but they lose about 33% to 50% of the HP of the motor.
If you want to talk about replacing the motor with a single phase one, I can help. The motors are odd sizes and often feature the outdated 3/4" shaft size. It is best to find a motor that is appropriately powered for your needs and make a motor mount adapter and buy or bush the pulley to size.
For wood type, I would think the 1 hp motor that was originally supplied with the saw would be a decent amount of power and I would replicate that. I would definitely want a TEFC motor (totally enclosed, fan cooled) for use around sawdust.
Pete
Welcome to the forum.
There are two options that you have presented. Option one involves modifying the saw, option two involves modifying your electrical supply.
Knowing more about how you will want to use it helps decide which is the correct direction to go in.
If you told me you would be buying more 3Ø equipment, I would recommend a rotary phase converter. You can make these in house or buy a ready made one.
If you are going to have employees or turn it off and on very frequently, I would advise to take the time to convert it to a single phase machine.
For less effort, you can make 3Ø power with a VFD, Variable Frequency Drive. This is probably a pretty good option. There is much on the internet about VFD's, Id recommend the VFD section at practical machinist for advice on this subject, they are really into their electric http://www.practicalmachinist.com/vb/tr ... rters-vfd/
Static converters are cheap, but they lose about 33% to 50% of the HP of the motor.
If you want to talk about replacing the motor with a single phase one, I can help. The motors are odd sizes and often feature the outdated 3/4" shaft size. It is best to find a motor that is appropriately powered for your needs and make a motor mount adapter and buy or bush the pulley to size.
For wood type, I would think the 1 hp motor that was originally supplied with the saw would be a decent amount of power and I would replicate that. I would definitely want a TEFC motor (totally enclosed, fan cooled) for use around sawdust.
Pete
Personally, I shy away from cheap imported motors. If you are going to take the time to do the conversion, I prefer a motor worthy of your time like a Leeson or Baldor.
I have always use a piece of metal as a mounting. I prefer to tap it for the motor mounts and drill holes to mount to the machine. This way the bolts for the motor are flush to the base of the plate and it is easily positioned. Think 5/16- 1/2" thickness for the plate. I'll often use aluminum because I have a bunch of it about.
You may also need to modify the belt guard, easy re-drilled.
I looked at one of my saws today and it had a 7/8" shaft on the 3Ø motor, so you may get lucky and not need to replace the pulley.
What model saw do you have?
Pete
I have always use a piece of metal as a mounting. I prefer to tap it for the motor mounts and drill holes to mount to the machine. This way the bolts for the motor are flush to the base of the plate and it is easily positioned. Think 5/16- 1/2" thickness for the plate. I'll often use aluminum because I have a bunch of it about.
You may also need to modify the belt guard, easy re-drilled.
I looked at one of my saws today and it had a 7/8" shaft on the 3Ø motor, so you may get lucky and not need to replace the pulley.
What model saw do you have?
Pete
I have my saw now
It is different from the one I was originally looking at. The model is G44B and the serial number is 7521.
I still have the same problem with a 3 phase motor and will probably need to go the replacement motor route.
I do want to consider the static phase converter route.
I realize that I will lose 30% or so of the rated power and that should not be a problem. My current saw uses a 1/3 horse power motor and it is adequate. It does bog down if I push too hard but it seems that losing a bit of power to a 1 hp motor would not be a problem.
The question is whether that is the only thing I will encounter. I often use my current saw for an hour or 2 at a time continuously.
Thanks for your help. The new saw is really clean and the motor appears to be the only problem that I need to solve.
Bill
I still have the same problem with a 3 phase motor and will probably need to go the replacement motor route.
I do want to consider the static phase converter route.
I realize that I will lose 30% or so of the rated power and that should not be a problem. My current saw uses a 1/3 horse power motor and it is adequate. It does bog down if I push too hard but it seems that losing a bit of power to a 1 hp motor would not be a problem.
The question is whether that is the only thing I will encounter. I often use my current saw for an hour or 2 at a time continuously.
Thanks for your help. The new saw is really clean and the motor appears to be the only problem that I need to solve.
Bill
Hi Bill, I don;t have great experience with the static converters, but would think they would have a rating on them to determine the duty factor. I would assume that if they have a standard service factor of 1.15- common to most motors they would be fine running the saw continuously for 2 hours.
Of course, with any motor if you tried to start and stop it hundreds of times in that period you might start to have a problem. Running continuously creates way less stress on the motor than starting.
Pete
Of course, with any motor if you tried to start and stop it hundreds of times in that period you might start to have a problem. Running continuously creates way less stress on the motor than starting.
Pete
I just got my 3 phase saw running on a 220 volt circuit
I bought a phase converter from Grizzly and it works great. I learned a bit watching my electrician get things running.
They say that the static phase converter robs the motor of power--around 30%.
Anyhow the motor is really smooth and I ran it for around an hour with no problems.
The saw will go through 1" thick maple without bogging down at all.
Of course that leads to my next question--about calibrating the finger scale. How do you calibrate the finger scale. I am using points and picas as I am making wooden printer's type so I am not converting to inches or anything. I just want to get the gage accurate to a few thousand's of an inch. I think this saw should be capable of extreme accuracy. It would be nice to get to .001" or finer and have it be dependable.
Here is a conversion from picas to inches:
American and English type measurement
1 line = 1 pica = 0.1656"
1 pica = 12 points
2 lines = 0.3312
3 lines = 0.4968
4 lines = 0.6624
5 lines = 0.828
6 lines = 0.9936
8 lines = 1.3248
10 lines = 1.656
12 lines = 1.9872
15 lines = 2.484
1 point = .0138"
They say that the static phase converter robs the motor of power--around 30%.
Anyhow the motor is really smooth and I ran it for around an hour with no problems.
The saw will go through 1" thick maple without bogging down at all.
Of course that leads to my next question--about calibrating the finger scale. How do you calibrate the finger scale. I am using points and picas as I am making wooden printer's type so I am not converting to inches or anything. I just want to get the gage accurate to a few thousand's of an inch. I think this saw should be capable of extreme accuracy. It would be nice to get to .001" or finer and have it be dependable.
Here is a conversion from picas to inches:
American and English type measurement
1 line = 1 pica = 0.1656"
1 pica = 12 points
2 lines = 0.3312
3 lines = 0.4968
4 lines = 0.6624
5 lines = 0.828
6 lines = 0.9936
8 lines = 1.3248
10 lines = 1.656
12 lines = 1.9872
15 lines = 2.484
1 point = .0138"
Bill,
Adjusting the finger scale is actually quite easy.
First set the finger and make sure the 12 position indexer is at zero.
Lock the finger it in place.
Make a cut using the finger and mic the piece that you have cut.
Without unlocking the finger, you can loosen the setscrew that is the zero position and rotate it to whatever setting your micrometer read.
recut and make sure it is spot on.
Yes, it is just this simple.
It you have the setting block- a piece of cast iron ribbed beyond belief you can use that to assist.
I hope this is clear.
Pete
Adjusting the finger scale is actually quite easy.
First set the finger and make sure the 12 position indexer is at zero.
Lock the finger it in place.
Make a cut using the finger and mic the piece that you have cut.
Without unlocking the finger, you can loosen the setscrew that is the zero position and rotate it to whatever setting your micrometer read.
recut and make sure it is spot on.
Yes, it is just this simple.
It you have the setting block- a piece of cast iron ribbed beyond belief you can use that to assist.
I hope this is clear.
Pete
I think I understand.
I will try it first thing tomorrow--I am done for today. I moved machines around all morning. Oh and disposed of a lot of saw dust.
Thanks
Bill
Thanks
Bill