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View Full Version : Mach 3 control of DC Brushless motor?



templecorran
10-08-2009, 03:26 PM
I'm keen to get a DC Brushless motor (DCBM) going much like Jeremy did for his spindle project ( is it really 2 years ago?).

Mach claims to have a PWM output, has anyone tried using that to drive the DCBM driver module?

I'm hoping that this is a solution to the noise my router makes! Also most routers aren't rated for more that 3 or 4 minutes running anyway. I typically run mine for up to 1 hour.


the duty cycle topic is discussed else where

John

HankMcSpank
10-08-2009, 03:56 PM
Can't answer your querey, but as someone who was equally concerned about spindle noise levels, one solution is a Proxxon BFW 40/E spindle.

AudioAndy lent me his, here's his video of it in action...


http://www.youtube.com/watch?v=gYanKmyzLfg

it's astonishingly quiet. The only downside is that its max RPM is 7,000, there's no 6.35mm collet available & it maye be a little underpowered for some (I believe it's 250W) - but hey, you can' t have it all...if it's quiet you want and can live with those downsides, it's a contender.

templecorran
10-08-2009, 04:22 PM
well, thanks for that info. That thing is so quiet I'm not convinced it is even running ... I don't see any cuttings!

I have gathered a lot of 1/4" and 1/8" shank tools so I must have the 1/4" chuck.

Starting at the beginning of Jeremy's series on the self build spindle - he is using an ER16 straight shank milling chuck. I checked and there weren't any imperial collets listed that I could see. I'm now searching for imperial milling chucks similar to the ER16 that might be made to work. I'm not afraid to run it through the lathe and make a mess! :heehee:

John

HankMcSpank
10-08-2009, 04:32 PM
well, thanks for that info. That thing is so quiet I'm not convinced it is even running ... I don't see any cuttings!

I have gathered a lot of 1/4" and 1/8" shank tools so I must have the 1/4" chuck.

Starting at the beginning of Jeremy's series on the self build spindle - he is using an ER16 straight shank milling chuck. I checked and there weren't any imperial collets listed that I could see. I'm now searching for imperial milling chucks similar to the ER16 that might be made to work. I'm not afraid to run it through the lathe and make a mess! :heehee:

John

well it was running! (& as I have it at the minute, I can confirm it really is that quiet)

The collets that come with it are 2mm, 3mm, 3.2mm, 4mm, 5mm & 6mm.

I'm considering buying an extra Proxxon 6mm collet & boring out the extra 0.35mm needed! (because if I ever need to use a 1/4" bit...it'd be for 'grunt work' & therefore accuracy wouldn't be key, so the little runout I cause shouldn't be a problem! )

templecorran
10-08-2009, 05:01 PM
in the past 30 something minutes I have found some interesting things out there in .net land :smile:

ER11 C8 100L (ebay ref 170370225742) and ER11 16mm dia (ebay ref 110391685240) (only good for a few days until the time's up)

However I also found Specifications for these collets, which all you mechanical engineering types knew already.
Bottom line is that I can easily make use of either the 8mm dia or 16mm dia chucks and attach them to a DCBM.

Now ... off autocad land to make some drawings :wink:

John

John S
10-08-2009, 08:11 PM
What about this one

http://www.arceurotrade.co.uk/Catalogue/Collets/ER-Collets-Collet-Chucks/ER16-Collets-Collet-Chucks

Part way down the page, ER 16 on a 20mm parallel shank.

ER16's are good to 10mm
I suspect you have found out but they close a full mm so they will hold any size.

6 to 7mm will hold 6mm and 1/4", 3 to 3.5 will hold 3mm or 1/8" and 9 to 10 will hold 3/8" and 10mm so you only need about 4 collets to hold eith standard sized cutters.

templecorran
11-08-2009, 12:55 PM
Yes, John, That's the one Jeremy used in his spindle design. Must confess I didn't notice the 1mm range in compression. After all, we were told as apprentices "that to be an electrician you need to be able to read or write, not necessarily both!"
I've now got a MSc in Electronics but keep that quiet :heehee:

I was thinking along the line of the smaller shaft for ease of coupling to the DCBM, but looking at the spec for them I see they feature a 4 or 5mm shaft. So a bit of lathe work is needed whatever way.

John

HiltonSteve
11-08-2009, 01:25 PM
I am watching this thread with great interest because building my own spindle and interfacing it with mach is something that I also would like to do.

The mechanics will not be a problem for me but designing electronic boards and putting them together has never been one of my strong points!

What I do have though is a selection of various good quality DC motor speed controllers that may be of use and would be happy to send one to you if it will help. Let me know the spec of the motor and I will see if I have anything that will be any good to you.

John S
11-08-2009, 02:59 PM
What I do have though is a selection of various good quality DC motor speed controllers that may be of use and would be happy to send one to you if it will help. Let me know the spec of the motor and I will see if I have anything that will be any good to you.

Don't give him one of MY damn DC speed controllers..........:surprised:

.

HiltonSteve
11-08-2009, 03:20 PM
Well I wasn't going to give him one of mine....:naughty:

You better add one of them to your 'u owe me' list as well.

templecorran
11-08-2009, 05:19 PM
Now now boys, Calm down... no fighting.:nope:

I don't need one "of YOUR damn DC speed controllers".
I can make my own!

HiltonSteve
11-08-2009, 05:36 PM
I don't need one "of YOUR damn DC speed controllers".
I can make my own!

Smart arse.......


But seriously, if you do want one they are four quadrant, digital speed controllers, switchable between 24-36v 200A max, speed control accepts 0-5v or 0-5ohm, forward and reverse, fully programmable acceleration and decel. All parameters changed by using 3 buttons on the front. Lots of either features that I won't go into. If you want a manual then I can email you one so you can have a look to see if there any good to you.

As long as you point me in the right direction for when I do my spindle electronics then you can have one for nothing.

And before John says anything, yes they are mine!

templecorran
14-08-2009, 02:40 PM
This is off topic but I wanted to share this info with you all:
Our 2nd year Mechanical students are expected to enter "The Power Tools HotRod races" by taking a battery operated power tool and using it to provide the drive for a racing car.
The designs are many and various and often too fragile to race.
Having discussed with other staff over the past years, especially since Robot Wars was featured on the telly, what we could do to build an entry for the competition.
The Hot Rod challenge is not so hard, as all you need is a bit of light board, a motor and battery.

My friend found these motors:
http://www.greenweld.co.uk/acatalog/Shop_LowVoltage_347.html
and we put together a challenger for the race.

That's not the point of this post:
My point is that these motors exist, are very cheap, will pull the solid curd off rice pudding (bowl and all) and run fast.

However, I'm not so sure that in it's raw state without a reduction drive that it would be suitable for life as a spindle motor.
:feedback:

John

templecorran
10-11-2010, 11:23 AM
It's now a year later since I was active on the forum.
Wifey made me a present of polystyrene sheeting for my shed last Christmas. The upheaval of lining the walls and roof left the shed in an unusable state. and on it goes... I wonder if she was telling something? Anyway, now I'm back to running my redesigned in Aluminium Rockcliff model A.

I'm desperate to get a quiet as possible spindle that can handle bit sizes in the range 3/4" (1/4" shank) to 0.050" (1/8" shank). The 3/4" is a router bit and may only ever be run in my 1020W B&Q router.
I stumbled upon a series in cnczone (http://www.cnczone.com/forums/457977-post54.html) where a fine engineer (Herbertkabi) has designed and published his work.

He is adimant that he will not make spindles for others, so I'll just have to call in some favours with my colleagues and get help to make my own.

This thread is about Mach3 control of DCBLMs. If Mach3 outputs a PWM, is it reasonable to assume that it has similar parameters to the Radio Controller Modules??
In which case if it does, then the conclusion to this thread is YES.

Jonathan
11-11-2010, 04:21 PM
'similar parameters to the Radio Controller Modules'

You might fins what I've posted on this thread (towards the end) very relavant:

http://www.mycncuk.com/forums/showthread.php/2122-Fingers-crossed-it-ll-cut-ally

M250cnc
18-11-2010, 04:20 PM
Have you considered a water cooled spindle

They come in ER16 size you need a VFD to use & control the speed OK in Mach3

They run from 8 to 24K

As they use water for cooling they should be pretty quiet as it's the air cooling fan that makes the noise in routers

Search for lovehappy shopping on that well known auction site he has a good reputation

Phil