Re: [CAD_CAM_EDM_DRO] Anyone Convert BOSS to servo's?

Hi Scott,

The Z axis can be changed to 2:1 using a smaller pulley on the motor.
The next smallest standard size belt gives pretty much the correct
pulley centres. Unfortunately the belt now fouls one of the gearbox
studs so you need to shift the motor back by about 3/4". It takes a
while to move the hole with a die grinder :-(

The X and Y can be changed to about 2.6:1 by using 15mm wide 5mm pitch
HTD belt. I have forgotten the exact pulley sizes but I can look them
up. Y is dead easy but X is a bit more awkward because the shaft is
quite large diameter and you also have to clear the ballscrew lube pipe.
I removed the old pulley (it was VERY tight) and machined about 1/4" off
it's width. I then turned the inside of the new pulley to 1/4" thick and
the correct diameter. The old pulley then became a spacer to go behind
the new pulley.

Les

Polaraligned wrote:

>Thanks everyone for your detailed answers on servo vs. steppers on the
>BOSS machine. I have aquired 3 servo motors already, as I was going
>to convert my '69 series 1 to CNC. I just aquired this BOSS 4 last
>week, thinking it would be easier, and better, to upgrade the BOSS 4.
>My BOSS is a 1:1 drive ratio and the servos I have (and most servos)
>need a higher ratio. I need to get at least 3:1 or higher. Problem
>is that I don't think it is possible to do, at least not reasonably,
>on this machine. The X axis has the ball housing (whatever it is
>called) driven, and not the screw itself. The pulley on it is quite
>small, so I don't think I can reasonably up this 1:1 ratio. The
>spindle pulley does not look easy to up the ratio on either. I would
>probably have to make the current driven pulley an idler pulley and
>add another belt. This does not seem like a good way to go.
>An extra stage of reduction will introduce errors.
>Maybe this all points to keeping the steppers. (which are a strong
>consideration) A servo conversion actually seems easier to do on a
>non-CNC machine.
>
>Has anyone done this BOSS to servo conversion? If so, how?
>
>
>Thanks,
>Scott
>
>
>
>
>
>--- In CAD_CAM_EDM_DRO@yahoogroups.com, Doug Fortune <pentam@c...> wrote:
>
>
>>My SuperMax cnc mill has the original Nema42 triple stack 1100 oz*in
>>Superior Electric motors, driven by Gecko G201s with my 72VDC
>>
>>
>
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