motorised mill

[Bluechip]

Hi Malcolm

Only if it is a permanent magnet motor.

If it is series connected, or shunt connected, the armature current will reverse, as will the field current.

A 'reverse with a reverse' will mean it still goes in the original direction.

You have to switch either the field OR armature connections, but not both.

I suggest inserting the c/o switch in the armature supply, rather than the field.

It's easier, the connections of the field are often split either side of the armature.


Dave

 

[tel]

Easy peasy mate - just a double pole, three postition switch (ON. OFF. ON.)

Take your power wires (pos & neg) to the middle connections. Now take your first set of motor wires to one end of the switch. Now, put in two links, that change sides to the other end of the switch - done! I got 'arf a drawer full of those switches - I'll dummy one up & take a pic for you shortly.

 

[tel]

Here y'go - the two wire running off right and left are the pos & neg of the supply, the two heading south go to the motor.

 

[jack404]

The shopping list is getting bigger

the cheque will clear and i'll be broke again in 4 hours (maybe 3 )

cheers for that tel

jaycar 2 x double pole 3 posi switches

sorted!!!

cheers

jack

 

[tel]

Tel
I've been sitting looking at two wiper motors in my shed for about two years. :-\
AWAY WE GO.
PS Used to be three but one turned into a BBQ rotisserie.
BR

;D I've used dozens of the things over the years, they are grand little motors for all sorts off applications. Down to me last 4 or 5 now tho' - might 'ave to go 'midnight shopping'

 

[jack404]

drop in down this way tel

our "unidentified middle eastern friends " dump 2-3 cars a week at the end of the road minus various bits

Sydneys strange that way

i miss Adelaide....

 

[Bluechip]

Hi Folks

Yup Tel,

Easy to do provided it is a permanent magnet motor. But it will not work with a 'wound field' motor.
The sense of the magnetic field if the armature must be reversed with respect to the fiels coils to reverse a non permanent magnet motor. Otherwise it will still go in the direction it first thought of

It can be done by inserting a bridge rectifier in the circuit tho'.

I can't post pics, one of the many 'tuits' I need to get a grip of sometime, but if you want I can email you some simple diags I did when I had to get some motor theory into the whippersnappers at work

Dave

 

[tel]

Wouldn't mind a look at wot you've got Dave, tho' I've yet to find a windscreen wiper motor that didn't work with that set-up. Also get the choice of the two speeds through another, identical switch, used t'other way round.

I did have trouble trying to get a starter motor to run t'other way, that was for a winch project I had in mind - gave up in the end and (shudder) bought a winch.

 

[Bluechip]

Hi Tel

Will Do. Will also take a pic or two, better than my diags. About 24 hrs. Gotta go to hospital shortly, to have my arthritis fooled about with. There'll be ten or so folks there, all with 2PM appointments.
PITA.
Still, an internal Nark session won't go amiss. Long time since I enjoyed one.
Dave

 

[tel]

Good luck with it mate. I hate 'ospitals with a passion.

 

[Bluechip]

Hi Tel

Me too :'(

email sent I think

dave

 

[firebird]

Hi

This is nothing to do with motorising the mill but shows how versatile wiper motors are. Both julian and myself built one of these wiper powered saws when we first got going in model engineering. Much easier than cutting by hand. They really are quite powerful.

Cheers

Rich

 

[jack404]

Rich

wished you hadda put that up a week ago

woulda saved me the bucks i sent to the US to get a hand held band saw

oh well it will be here monday

but will keep that in mind

it looks bloody fantastic!

wish i had the ideas you folks get

all my brilliant ideas generally go BANG!!

cheers

jack

 

[firebird]

Hi Jack

You will find it posted on this forum somewhere, do a quick search and you will find it.


Cheers


Rich

 

[jack404]

GOT IT!!

thanks mate i'll post it alltogether with the text and PDF it and
and send it back to you for your approval before uploading to the downloads section

cheers

jack

 

[malcolmt]

HI Bluechip

"Hi Malcolm, Only if it is a permanent magnet motor."

OOPS !!! Yes of course you are absolutely correct. I must have been half asleep when i added that little gem of misinformation. SORRY folks, Thanks for spotting that BC.

Kind regards

Malcolm

 

[firebird]

Hi

We have upgraded the motorised mill. The stepper motor we originally used was OK but not powerful enough. I bought a new motor from arc eurotrade ( check their website, they are on offer at the moment ) The new motor has a power rating of 220Ncm compared to the 70Ncm of the old one. The old motor had a small 6mm shaft so I had to make an adapter to fit into the slot in the end of the lead screw

The slot in the end of the lead screw

The new motor shaft is 10mm with the old adapter on the right

I decided to cut the shaft on the new motor to make a tang that would fit directly into the slot. The slot is 4 mm wide. I cut the motor shaft down to 3 mm with a dremmel type tool and then fitted a piece of rubber to pack/cushion the drive.

Julian did the technical bit, rewiring the motor to the control box. He has wired it to give maximum torque. I'll get him to fill in all the details and answer any questions.

To test the new drive I clamped a bit of inch round bar in the vice and chucked the biggest end mill I have. It performs beautifully. Heres a video of the test.



Cheers

Rich

 

[mnewsholme]

I am currently working on a bolt on kit for the X3 X axis with a simple controller.
The only problem is the kit is fine but the controller can't be sold as a completed item because of the CE hurdle.
Probably it will have to be sold as a kit and assembled at home.

I was hoping to have it at the Midlands show but it won't be there because of pressure of work and the CNC's taking centre stage.

.

has this project progressed any further john?

Matt