Servo motor question

[Mrstsb]

In the UK there seems to be a choice of 2 sizes/power of servo motors. One is a 550w and the other is a 750w. Obviously there is a slight difference in price between the two but would there be any reason to have one over the other? Would the 550w one be more than adequate for sewing leather or for the sake of £30 would you go for the more powerful one?

[Northmount]

Obviously the answer depends on what you are sewing including the thickness and temper of the leather, and how slow you want to go.  Without those facts, there is no real answer.

[Mrstsb]

3 hours ago, Northmount said:

Obviously the answer depends on what you are sewing including the thickness and temper of the leather, and how slow you want to go.  Without those facts, there is no real answer.

No idea what I will be sewing at my stage of learning, just having a play with different materials at the moment. As to the speed, they are both quoting 200spm to 5000spm for the 550w and 3500spm for the 750w which doesn't make sense to me

[Northmount]

55 minutes ago, Mrstsb said:

No idea what I will be sewing at my stage of learning, just having a play with different materials at the moment. As to the speed, they are both quoting 200spm to 5000spm for the 550w and 3500spm for the 750w which doesn't make sense to me

At least give some specs for your machine.  Machine brand and model, maximum thickness it can sew, maximum thread size it can use.  If you are a beginning sewer, even 200 spm is fast when you are trying to follow a curve or go around a corner.  If you aren't surer what you are going to be doing, it might be best to do some had stitching for a few items, then see where you want to go from there.

[kgg]

1 hour ago, Mrstsb said:

which doesn't make sense to me

If both are brushless servo motors there will be less torque, punching power, available on the 550 watt and spread over 5000 rpm while the 750 watt will have more available torque spread over less rpm's, 3500 rpm. However that can be like comparing apples to oranges if they weren't constructed with the same number of coils. More coils basically equals more torque and are more expense. A expensive 550 watt with 12 coils could be better then a cheap 6 coil 750 watt. You really have to look at the spec of the servo motor for things like brush vs brushless, number of coils, speed range, torque rating, etc.

The cheap servo motors generally have 6 coils while the better high torque ones like the Reliable SewQuiet 6000SM have 12 coils.

What machine are you planning on installing a servo motor on? I personally have 550 watt brushed servo motors on my machines which may not be available or common in your country.

kgg

[Mrstsb]

19 minutes ago, kgg said:

If both are brushless servo motors there will be less torque, punching power, available on the 550 watt and spread over 5000 rpm while the 750 watt will have more available torque spread over less rpm's, 3500 rpm. However that can be like comparing apples to oranges if they weren't constructed with the same number of coils. More coils basically equals more torque and are more expense. A expensive 550 watt with 12 coils could be better then a cheap 6 coil 750 watt. You really have to look at the spec of the servo motor for things like brush vs brushless, number of coils, speed range, torque rating, etc.

The cheap servo motors generally have 6 coils while the better high torque ones like the Reliable SewQuiet 6000SM have 12 coils.

What machine are you planning on installing a servo motor on? I personally have 550 watt brushed servo motors on my machines which may not be available or common in your country.

kgg

Thanks for the detailed information regarding the motors. In the UK they are probably all imported from China and rebadged so I don't think I'll get the answers about coils etc. The machines I'm wanting to use them on are an old singer walking foot and a Karpet King carpet over edger

[kgg]

18 minutes ago, Mrstsb said:

The machines I'm wanting to use them on are an old singer walking foot and a Karpet King carpet over edger

With info being hard to come by I would probably go with the 550 watt on the Singer and the 750 watt on the carpet edger. You are probably going to need more punching power doing jute/hard back carpets.

kgg

[Mrstsb]

1 hour ago, kgg said:

With info being hard to come by I would probably go with the 550 watt on the Singer and the 750 watt on the carpet edger. You are probably going to need more punching power doing jute/hard back carpets.

kgg

Great, I think that's the conclusion I've come to as well.