Bridgeport cnc conversion?

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Koep
Posts: 3
Joined: Tue Oct 16, 2018 4:17 pm

Bridgeport cnc conversion?

Post by Koep » Tue Oct 16, 2018 5:10 pm

Hi All :D

I'm currently wondering if I should convert my old Bridgeport to CNC or just replace it with something else.

Major unclear is how to config for the combination of tilted milling head and quill feed.
In my workshop I have a fully analog person that needs the possibility to operate in manual mode.
Slaving the axes to hand wheels is not a problem, but I'd like to dump the whole milling head and replace it with belt driven spindle.
This means that I'd need a synced XZ move that is controlled "quill handle" encoder and where the ratio of X and Z is derived from head tilt angle obtained from abs encoder(as5048).
How would I go about slaving both X and Z to one encoder?

Has anyone considered or is anyone using SnapAmp with hubmotors from a hoverboard? I'm wondering if it would be feasible to use these as
integrated handwheel/axis servo?

Rgds,
Tapio

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TomKerekes
Posts: 212
Joined: Mon Dec 04, 2017 1:49 am

Re: Bridgeport cnc conversion?

Post by TomKerekes » Tue Oct 16, 2018 5:57 pm

Hi Tapio,
Major unclear is how to config for the combination of tilted milling head and quill feed.
In my workshop I have a fully analog person that needs the possibility to operate in manual mode.
Slaving the axes to hand wheels is not a problem, but I'd like to dump the whole milling head and replace it with belt driven spindle.
This means that I'd need a synced XZ move that is controlled "quill handle" encoder and where the ratio of X and Z is derived from head tilt angle obtained from abs encoder(as5048).
How would I go about slaving both X and Z to one encoder?
I'm not sure I entirely understand, but I would think you could do a Master/Slave configuration where X is Slaved to Z and the Slave gain was set based on the tilt angle which was periodically read from the as5048 via SPI. The Quill handle encoder would then move Z.
Has anyone considered or is anyone using SnapAmp with hubmotors from a hoverboard? I'm wondering if it would be feasible to use these as
integrated handwheel/axis servo?
I have no idea but found this if it helps:
https://hackaday.com/2016/06/10/reverse ... tor-drive/
Regards,

Tom Kerekes
Dynomotion, Inc.

Koep
Posts: 3
Joined: Tue Oct 16, 2018 4:17 pm

Re: Bridgeport cnc conversion?

Post by Koep » Tue Oct 16, 2018 7:53 pm

Hi Tom,

I mean this from 0:12 to 0:17 https://www.youtube.com/watch?v=QyW4-Rbju4w.

I imagine doing that with cnc/G-code takes hadful of drillbits for practice, but can this be done

in for loop of init file?
X slaved to Z, gain from tilt, Z slaved to quill handle encoder?

So basically the question is: Is (daisy)chaining slaved axes allowed/possible?

Rgds,
Tapio

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TomKerekes
Posts: 212
Joined: Mon Dec 04, 2017 1:49 am

Re: Bridgeport cnc conversion?

Post by TomKerekes » Wed Oct 17, 2018 1:33 am

Hi Tapio,

Yes that should be possible. Any number of Slaves can follow a Master. But I don't really see this really as necessary or a daisy chain in this case. It should be a simple Master/Slave situation where the Master is then commanded to move in some manner such as an MPG or other.
Regards,

Tom Kerekes
Dynomotion, Inc.

Koep
Posts: 3
Joined: Tue Oct 16, 2018 4:17 pm

Re: Bridgeport cnc conversion?

Post by Koep » Wed Oct 17, 2018 4:11 pm

Hi Tom,

As allways I find your answers very helpful. After rethinking and digging deeper I noticed that all that I need is already in the
c programs folder.
Since you have allready done the heavy lifting I figure I'll have few minutes of ctrl-c/-v, few hours to add the abs encoder with math for XZ relation, few days to figure out why it will not compile and general debug and presto "manual" milling machine for fully analog user.
Some more and rigid tapping with/without tilt should not be impossible

Rgds,
Tapio :D

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