# Spindle Resting Position



## mlepisto2 (Sep 24, 2014)

Is it normal for the spindle to drop quickly right down to the spoil board when the machine and air compressor are turned off?

Our router allows for the spindle head to drop very quickly when all is powered down. We currently have a wooden block in place that we have to carefully locate at the end of every session. Is this normal? Is there a better fix?


----------



## bcfunburst (Jan 14, 2012)

mlepisto2 said:


> Is it normal for the spindle to drop quickly right down to the spoil board when the machine and air compressor are turned off?
> 
> Our router allows for the spindle head to drop very quickly when all is powered down. We currently have a wooden block in place that we have to carefully locate at the end of every session. Is this normal? Is there a better fix?


Need more info to answer any question. Are you asking about CNC Router? I only use hand held and Table mounted routers. No dropping anything, allowed with those!!
I'm sure someone here will be able to help if we have a little more info.


----------



## Phil P (Jul 25, 2010)

Hi Mallory

"Spoilboard" sounds like a CNC to me. Every CNC I've used (Wadkin, SCM, Biesse, etc) has two ranges of movement for the spindles - the rise and fall into operating position is by pneumatics working against fixed limit stops (for raised and lowered positions respectively) together with a Z-axis screw for fine positioning. In the program there should be a command (or commands) somewhere at the end of the program which tells the machine to raise the head (pnuematics), park the head - so return to the X-Y axis home position (where the head is clear of the work area) - and finally to zero the Z-axis (i.e. move to the highest position the ball screw allows; note that the sequence on these may be Z-zero then X-Y zero). On a servo-driven Z-axis the servo motor combined with friction within the ball screw and ball nut will hold the head in place when the machine is powered down. If your head is dropping is the end of your program file missing a Z-azis zero command I wonder? Or possibly is there a fault with the Z-axis control circuitry? Which CNC/contoller are you running, may I enquire?

Regards

Phil


----------



## bgriggs (Nov 26, 2008)

Check you manual to find out if there is a park command. This moves the Z axis to a safe position and will prevent the head from dropping.

Bill


----------



## Phil P (Jul 25, 2010)

bgriggs said:


> Check you manual to find out if there is a park command. This moves the Z axis to a safe position and will prevent the head from dropping.


Unfortunately, Bill, they don't all work like that - older Biesse's needed to have the vertical spindel zeroed first befor issuing a home/park command. If not you'd end up wrecking a spoilboard and/or bending a cutter!

Regards

Phil


----------



## bgriggs (Nov 26, 2008)

Thanks Phil,

I missed the model router he was using.

Bill


----------



## Phil P (Jul 25, 2010)

Hi Bill

The OP didn't actually say, but having had the experience of that fault with one entire range of routers and being aware that CNI controllers were/are fitted to other brands I thought it best to mention an obvious flaw in at least one controller found out there in case other controllers had the same "feature"

Regards

Phil


----------



## mlepisto2 (Sep 24, 2014)

Hi there!

Sorry for the delayed response! I wasn't receiving notifications that anyone had replied to my inquiry. Thank you so much for your time!

I am operating a ShopSabre 4896 CNC Router. When done with running the machine for the day, I always send the CNC to the park position. If I manually lower the Z axis to zero then the head would be resting directly on the bed/spoilboard causing for the dust skirt bristles to fray. We place a wooden block underneath the head to prevent this from happening.

When we hired a professional to train us on how to operate the CNC and the software. He (with 20 years + experience) said that he had never, in his career, seen a CNC that allowed the head to drop like ours does. 

We have worked around this obviously, but was just curious if anyone else had experienced this issue.



Thanks again!


----------

