Another 4" CNC rotary table

[tumutbound]

It's probably a little late seeing you've already bought your stepper driver but ...

The annual Gecko sale is on so you can pick up a G251 driver for $US49.

It would easily fit in your existing enclosure.

[kwackers]

Looking good. Have you checked it changes direction if you press the opposite direction? (About all that's left to go wrong - mechanics excepted).

I doubt the driver will get that hot, if possible I'd build it into the box (mainly because I like stuff like that as self contained as possible).
Try running it for a bit and see how warm it gets.

[j45on]

tumutbound if I did not have one I would consider that 

kwackers I will check tomorrow I think I had the motor going both ways actually I'm sure I did as I increased the backlash compensation to see what it did and it was noticeable in one direction and that only affects one direction right ?

I was thinking about cutting out the back of the box so that the driver heat sink could poke through and seal it up with a bit of silicone but after playing around today the only thing that got warm slightly was the motor

[j45on]

Got some aluminium tube today for the stepper motor mount I'm thinking about machining the ends that fit the motor and table out of separate pieces and threading them into the tube and securing them with locktite


I found this while browsing another site it's a 20x4 character LCD with extra large digits ( great if you have poor eye sight )
Would not fit the controler pcb but may be of use to someone
http://www.mcustore.com/displays-i-o-boards/56-20x4-large-digit-character-lcd.html

[cidrontmg]

Hi j45on, others,
I´m also building one of these, got finally all the electronic components, still missing the stepper + mechanicals. I will mount the electronics to an Eddystone cast ali box, looks like this. The keypad has ready printed symbols, so it won´t look nearly as nice as yours. But I guess I can live with those.
The bombproof box is so far otherwise empty. I´ll use stripboard and solder some components during the weekend.
 

[j45on]

Looking good Cidrontmg
That is one bomb proof looking box 
Keep us posted with updates

[Bogstandard]

OK, I have read all the posts, and I even got totally baffled by the very first one.

I am OK with all the cutting out bits, hacking lumps of metal up and soldering thingies up, but how on earth am I supposed to make the boards and get all the components together when I am completely at a loss about them. It is 30 years since I was 'into' elektronical bit's n bobs, so you can understand how far behind I am.

I really need to make something like this to help me because of the very limited power I have in my hands, and I have power drives on everything except for the RT.

Does anyone do a full electronics and bits kit for this control box, or do I have to succumb to the lesser and more expensive Division Master.


Bogs

[j45on]

I have still not finished this yet my standoff's have still not arrived
I did run it for a while at the weekend and the only thing that got hot was the
voltage regulator it needs a bigger heat sink I think.

Bogs how much would you want I could build the board for you ? I have some spare components.
Or would you need a built unit ?

[Bogstandard]

Hi Jason,

If you look at the second picture for the division master, as a kit. It doesn't need to have the main box cutout or any assembly. Just a means of me having together in one place all the bits required to make it and it's power supply.

http://medw.co.uk/wiki/index.php?page=DivisionMaster

It is such a daunting task for me now just to find a few item of electronics that I can remember and understand about. When you guys are on about writing to pics etc, and which bits to buy from where, my mind goes totally blank because of all the new technology that I just don't understand.

I was going to buy the Divisionmaster kit, but John Stevenson recommended the one you lads are building because not only does it work out cheaper, supposedly it has better functionality.

BTW I am not expecting charity, I am quite willing to pay for the help to achieve what I need.

I now know what you lads who can't reach the higher levels of machining feel like, it is the same feeling for me when it comes to things like this.


John


ADDED

Or, if someone can supply me with complete details of what to order and from where, plus how to get hold of a board, ready blown pic and overlays, plus anything else that is needed, and where to obtain them from.
I don't know if it makes any difference to the component list, but I want it for a 6" rotary table, which supposedly uses a larger stepper than one for a 4".

[John Stevenson]

Bogs,
If you are willing to use an old laptop or desktop computer I can supply everything except the table.
It will be a box with mains plug on, USB plug for the computer and a lead out going to a stepper motor.
You start the computer, start the program and this is what you see.



Does basically all a Division master does but not hand held.

John S.

[spuddevans]

I know I'm coming in a little late ( as usual ) but I just wanted to throw my hat into the fray and offer to get and burn the pic for you John. I cant make PCB's yet, but I guess I could botch something together out of stripboard if it was needed.



Tim

[kwackers]

And back on track...

How many people would be interested in a 'kit' of parts? I've only done some preliminary research but I'm guessing the components would run to around £15-£20 (no connectors, presume soldering wires to the board edges for connections) with pre-programmed PIC's, and with say 10 people on board PCB's would run an extra £10-£15.

On top of this to complete the whole thing you need:-
A keypad (£13 ish from Farnell if you used the one I use), a box (say around £10).

Then depending on what you were driving - but lets say a typical 4"-8" rotary or lathe head or similar dividing head, then:-
Stepper motor (say £25), along with a stepper motor driver (typically around £35) and a power supply (say £25).

Some savings can be made, you can find cheaper drivers or even make one (say using a L298/L297 pair for around a tenner), laptop power supplies (18v plus) are ideal for driving this and can often be found v.cheap or even free and a bit of digging around may find savings on the keypad (or you can make your own) and stepper motor.
Finally you can build it on strip board saving the cost of the PCB, although the more people were interested in PCB's the cheaper they get - e.g. aprox £100 for 10 and £250 for 100 (assuming my original PCB design can be used).

[Spurry]

Not sure where the queue starts, but would like to put my name down please.

Pete

[BillTodd]

Hi Kwackers,

You can put me down for a  kit, or just a PCB if that'll help. 


Bogs - I'm sure young J45on will do a fine job, but if you need someone to solder a kit together, give us a shout.


OT:

I've been browsing most of the engineering forums for a while now, and it is remarkable, out of the hundreds of semi-anonymous posters, how just a few names stand out as the advice and assistant providers. Bogs here is one of them - treat him well or bemoan his loss!

Bill

[slowcoach]

Hi Kwackers, put me down for one please,if you decide to offer them, I would certainly be up for a kit   A proper printed PCB would be very helpful to ease assembley

Cheers
Rob  

[HS93]

yes me to a full kit or whatever you can do

thanks for your offer

Peter

[z3t4]

Jeez! A bloke spends a few days away with his Jaffa cakes and returns to carnage!!
I got this lot from Farnell in the summer, waiting for the cold weather. The part numbers work,
* means I had some in a bucket somewhere. And the formatting's crap. Sorry a bit better now .

Part Number

Value

Farnell

Qty

Notes

C1, C2

33pF

1141761

2

C3, C4

100nF

1469310

4

Decoupling -- spread liberally.

C5

470uF 25v elec

9451200

1

VR1

10k Preset

1689844

1

Contrast control

R1 - R4

10k

*

4

Keypad pull downs

IC1

18F452

9762230

1

Pre-programmed with firmware.

IC2

7805

1755508

1

And small heatsink.

40 pin IC Socket

4285669

1

For PIC 18F452

Xtal

10Mhz

1611856

1

Keypad

4 x 4

1171224

1

(or 16 buttons)

LCD 4line x 20

*

PCB

Or stripboard construction.

8 Pin SIL socket

1218869

1

Only if using Farnell keypad.

Case

Power supply

To suit stepper/stepper controller.

Beeper

LS1

Passive sounder

1192513

1

Q3

BC337

1574379

1

NPN transistor (500mA IC)

R5

4k7

*

*

D2

BYV27

1469371

1

Any fast switch diode

Sense/Ack

D1

BYV27

1469371

1

Any fast switch diode

Q1, Q2

BC337

1574379

2

NPN transistor (500mA IC)

R8, R9

4k7

*

*

R6,7,10,11

10k

*

*

HTH

John

[tumutbound]

I  created a component list with Mouser a couple of weeks ago.. Total cost of everything except PCB is approx $US43 - plus shipping.
I don't know if Mouser is an option for UK based purchase but I can share the project file if anyone is interested.
I can do the same with Digikey if there's interest.
Update: $23 of that cost was for a 20x4 LCD. You can pick these up from a number of online sources for $10 - $12

As far as PCB go, I use pcbcart.com which is a Chinese based manufacturer. Prices are pretty good e.g. 20 off 100mm x 150mm double sided boards, silk screen cost $US144. Turn around of 12 days.  Artwork must be provided as  Gerber files.
There are also a couple of places that specialise in prototyping boards i.e. 10 boards, 100mm x 100mm double sided $US28 plus shipping. Add an extra $US10 if you want blue boards.  
I haven't checked the size of the driver board  so don't know how useful this information is.

[Brass_Machine]

I am not happy with direction this started to take. I am glad to see that it has gotten back on track.

So let's cool the hostilities. We are all adults here. This is Jason's thread... I am removing the posts that do not add to this thread.

Eric

[Bluechip]

Bogs,
If you are willing to use an old laptop or desktop computer I can supply everything except the table.
It will be a box with mains plug on, USB plug for the computer and a lead out going to a stepper motor.
You start the computer, start the program and this is what you see.



Does basically all a Division master does but not hand held.

John S.

PS Send photo of hairy arse.

Last line of this looks a bit  .. er ... surreal now Eric   

Dave BC