Centec 2b

Hi all I recently brought a Centec 2b local to me very cheap with a quill head

Didn’t realise the size of the swarf tray

2 questions

I need a new bellows for the z axis lead screw what do people use

also I use carbide end mills don’t have hss I find 1400 rpm a little slow for using the vertical head

do people change the motor to a more powerful 2 pole or play around with different size pulleys thanks in advance

Re the bellows, it's not very elegant, but I use a modified macadamia nut tin to provide a shield/mounting for the lower end and a corrugated shock absorber cover for the main bellows unit.
It seems to work fine.

I'm not sure I would want to run the main gearbox as fast as a two pole motor.
Maybe consider a second variable speed motor to replace/drive the rear V pulley on the vertical head.

Bill

Vertical head gets pretty hot if you run for extended periods at 1400 rpm, I wouldn't want to run it any faster

Yes fair point, and also worth considering removing the chuck, if on MT2 taper, whilst it's still warm, to save it jamming tight when it cools down.
Don't ask me how I know.


Bill

and also worth considering removing the chuck, if on MT2 taper, whilst it's still warm, to save it jamming tight when it cools down.
Don't ask me how I know.

Too late by then. That will make no difference at all. Problem arose when a cold taper was inserted into a warm socket.

On my 2B I kept the original 3ph motor, converted it to delta by splitting the star point, and run it with a VFD. This gives me a speed range from about 30-2800 rpm. I've not experienced problem using carbide tooling, and it makes tapping under power a doddle.

Almost exactly the same except I changed mine, from the (non-original) single phase fitted, to a 3 phase motor.

I’m not sure whether the vertical head rpm’s are the same as the horizontal output - I’ve simply never checked.🙂. I don’t thinkI’ve ever exceeded about 2000 (indicated rpm) on mine.

The power feed is operating perfectly adequately using the 3 phase motor and a 240V VFD.

I would not actually recommend a more powerful motor. The 2B was increased from 3/4HP to 1HP (over the 2A model). I am not aware if the gearbox internals were changed at all. If not, that is already a 33% increased rating. Mine can actually deliver about 1.2HP, but I am careful not to use all the power available. My Centec is a valuable asset and I don’t intend to try to destroy it by over-loading it!

Is you Centec 2b motor a 2800 rpm motor as standard mine is only a 1400 rpm

There is a 7:8 ratio between, can't remember which way

Centecs were available with 2800rpm motors. There has been a previous discussion on here.