Slow Down A CB4500

[1Poet]

Hey All,

     I apologize for not having a profile up, but it doesn't load for some reason. Anyway, I have a new to me CB4500 and I have a problem with the speed, especially starting up. I do not need anything fast, but would like to start slow and keep it slow. However, the foot pedal is something that requires a lot of pressure to start and does not seem to be very sensitive to my foot input. I am doing short length stitching on smallish items, 4" to 8". Is there any way to make the servo start slow and stay slow? I have tried everything I can safely try, but no solution. Advice greatly appreciated.

[kgg]

14 minutes ago, 1Poet said:

I have a new to me CB4500 and I have a problem with the speed, especially starting up.

A couple of questions:

i) does your machine have a speed reducer or just one belt from the head directly to the motor??

ii) does your machine have a clutch motor or a brush servo motor or brushless electronic servo motor???

iii) what size of motor?

A couple of photo's would help clear up your particular setup and narrow down possible solutions.

kgg

[Wizcrafts]

15 minutes ago, 1Poet said:

Is there any way to make the servo start slow and stay slow? I have tried everything I can safely try, but no solution. Advice greatly appreciated.

First of all, what type of servo motor is installed on the machine? Does it go directly from the motor to the machine? Or, is there a speed reducer between them?

In the early days of the CB4500 and Cobra Class 4 machines (e.g., 2011 - 2013), they all had digital servo motors with a readout display and push buttons to change functions. these motors started spinning at about 200 rpm. Sometime after that, they began to ship with analog servo motors featuring a simple knob to limit the top speed, plus a 3:1 speed reducer to triple the torque. My analog servo and speed reducer lets me sew so slowly that it's like watching grass grow if I just slightly engage the speed pedal.

[1Poet]

Wiz,

My machine has the analog servo with a single knob for speed. I have it set on the lowest setting. It has the 3:1 speed reducer. My issue is do I have the pedals and connections set right or is it something else. On start up I have to push on the foot pedal a little too much and then try to slow down to a slow speed. I would like to adjust it where I start slow and it will run slow. I currently don't have it running fast even with the pedal all the way down.

BTW, thanks KGG, I think Wiz has nailed what I have.

[dikman]

As mentioned, photos will help, particularly the foot pedal linkages and where they connect to each end.

[Northmount]

7 hours ago, 1Poet said:

I have a new to me CB4500 and I have a problem with the speed, especially starting up.

Moved your post to leather sewing machines.

[1hp]

i put a 40mm pulley on the motor. made it a lot easier to get used to the machine.

https://www.ebay.com/itm/124309601543?var=425199910545

in addition to having speed reducer. no expert here.

 

Edited July 12, 2024 by 1hp
more info

[1Poet]

Hey, y'all! I don't know how to add photos! DUH! Any guidance appreciated!  

[bladegrinder]

I have a CB4500 and notice a big improvement as far as pedal reaction to foot pressure by removing the brake pad in the back of the motor. you could try that and if you don't like it just put it back.

 

 

[bladegrinder]

To add a picture, it has to be resized for this forum to take it. I resize mine to 650 as the largest size, then save that resized photo, come back here click add a photo and choose the one you just resized.

anything bigger and it won't post.