Power Feed to Milling Machine Table

[AjohnwParticipant @ajohnw51620]

In some ways a stepper may be easiest because more or less off the shelf parts could be used. To avoid using a huge one a gearbox could be added. They can be bought with them but the costs tend to escalate and it's probably well worth buying or making gears to form your own.

I assume just like other drivers the TB6560 boards just need pulses for the drive and have a direction input. There are chips about that can produce a variable frequency output at the turn of a knob. I doubt if it would be much of a problem with these to cause them to run faster for the return feed if that is needed.

What I don't know is how fast the steppers can be made to rotate at. All I know on that score is that higher voltage ones such as 6 and 12v can produce a lot more torque but for a given supply voltage can't match the speed of lowere voltage ones. 24v volt for the supply is sensible anyway. Higher voltage drivers tend to be much more expensive.

The cheapest drivers I could find that really are in the UK are these

**LINK**

Not so sure about the others as RM are likely to deliver them where ever they come from. The above actually shows the connection details in the listing as well.

John

–

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Ajohnw on 03/08/2016 10:46:46:

In some ways a stepper may be easiest because more or less off the shelf parts could be used. To avoid using a huge one a gearbox could be added. They can be bought with them but the costs tend to escalate and it's probably well worth buying or making gears to form your own.

.

Toothed-belt drive, from an off-axis motor would probably be cheaper/easier/quieter.

MichaelG.

[AjohnwParticipant @ajohnw51620]

Did you notice feeds and speeds cropped up again Michael ? Cutting tools can't rub unless something is loose. Something usually is due to flex rigidity or what ever so there will be a min feed rate. + and depth of cut.

I thought gears so that it could be a nice compact unit. 1/2 or 1/4 stepping maybe to reduce noise but plastic gears are probably feasible.

Clutch – swing said motor in and out of mesh. I see that as an advantage as it's easy. Doing that with a belt wouldn't be so easy. I have a telescope drive that uses single stepping and brass gearing though and it isn't half noisy especially when it's quiet at night. Annoyingly it's the best one I have – old Vixen

This is on the back burner for me due to lack of info on max rotational speed. Not worth measuring the torque at my feed handle until I can get some info on that. At some point I will probably finish up buying to find out.

The wiper motor is for raising and lowering the head. Actually cost of a decent 24v wiper motor is likely to be similar to a 3" Nema 23. I had to look hard to get a new one at that sort of price.

John

–

Edited By Ajohnw on 03/08/2016 12:35:47

[Ian S CParticipant @iansc]

The 12v wiper motor that I use is run on 18v, 12v automotive electric motors are usually quite ok at up to 24v. i think the speed at the worm wheel is about 120rpm, that gives 60rpm at the lead screw, and 3 mm per rev. It's a Lucas motor, probably at least 40 years old, with a wound field, not like some /most with permanent magnet field, so the power supply doesn't need too much smoothing. I don't think a rough supply is very good with permanent magnets.

Ian S C

[MWParticipant @mw27036]

Would using a DC shunt motor be a good idea, if not a little big?

Michael W

[David lawrence 3Participant @davidlawrence3]

Hi all, The 24 volt truck wiper motor I used was new and cost around £ 100.00 . it only draws around 1/2 amp at 24 volt so a small power supply is all you need. I guess you could find a cheap one on ebay but I happen to have it lying around. They are used in tv studios a lot to lower and raise lights from the ceiling, I was in that game for years and had one on the shelve, the problem is its too slow, you need a motor that can go quite fast to quickly move the table from one end too the other as well as fine slow adjustment.

[AjohnwParticipant @ajohnw51620]

Interesting. I expect a wiper motor to draw over 10 amps really well loaded. May be wrong, have to see. In my case I want to raise and lower more than I can comfortable lift to any height. I know that because I had some trouble fitting the head and only just managed with the motor off.

When the supply arrives I can see what the stall current is.

I found a 24v NOS motor on ebay for about £20. Lucas. I may have to remove any built in gearing. They did make some that were just a bare motor but no luck finding one. Actually I am not at all sure what is in this one. Finding out what it does can wait for the supply to arrive.

John

–

[John Stevenson 1Participant @johnstevenson1]

JohnW

Cutting tools can’t rub unless something is loose ?????

That’s the biggest load of Bollocks I have ever read.

Take a 20mm bar and you take 1mm off it, it will measure 19mm. Stop the job with the tool still on it and measure it. Then start up again and it will rub. The only way it can’t rub is if the bar is 18.95 mm

[AjohnwParticipant @ajohnw51620]

Posted by John Stevenson on 03/08/2016 15:16:25:
JohnW

Cutting tools can't rub unless something is loose ?????

That's the biggest load of Bollocks I have ever read.

Take a 20mm bar and you take 1mm off it, it will measure 19mm. Stop the job with the tool still on it and measure it. Then start up again and it will rub. The only way it can't rub is if the bar is 18.95 mm

More Bollocks – not what I actually said

John

–

[John Stevenson 1Participant @johnstevenson1]

Sorry, copy and paste must be broken.

A tool left in contact with the work will rub – fact

Just as being welded to an armchair will remover the knapp off moleskin trousers

[Neil WyattModerator @neilwyatt]

Many wiper motors have brushes designed only to run in one direction as a recent correspondent to MEW pointed out.

Neil

[Enough!Participant @enough]

Posted by Michael Gilligan on 03/08/2016 11:04:12:

Toothed-belt drive, from an off-axis motor would probably be cheaper/easier/quieter.

I built my original version (before I got "the real thing"  ) that way and just as you say it was cheaper/easier/quieter. I cobbled together a 555 timer circuit, controlled by a pot, to generate pulses. Regular NEMA-23 stepper. I didn't have any form of clutch but I did incorporate a switch to disconnect one side of each winding during manual feed and it wasn't too bad. (A number of experts, elsewhere, told me that was a Bad Thing for any number of technical reasons but it worked just fine for me – I'll take my practice over their theory any time).

(Edited to remove phantom smiley)

 

Edited By Bandersnatch on 03/08/2016 17:25:45

[Michael GilliganParticipant @michaelgilligan61133]

Posted by John Stevenson on 03/08/2016 16:43:12:
Sorry, copy and paste must be broken.

.

[AjohnwParticipant @ajohnw51620]

Posted by Michael Gilligan on 03/08/2016 17:25:50:

Posted by John Stevenson on 03/08/2016 16:43:12:
Sorry, copy and paste must be broken.

.

You being ish again Michael. I'm not biting otherwise I would post 2 shots showing what happens when I run the same cut on my Boxford. JS is more or less correct but lathes vary. Until my bearings warm up mine tends to take a very light cut, a better one if it is warmed up but then any vibration in the machine also shows up in the finish. Some rubbing too at times when they have warmed up.

I did mention flex and etc when I originally posted and min depth etc. Hence use of Bollocks with a big B.

John

–

[NJHParticipant @njh]

John ( Ajohnw)

I was sat here musing about your prolific posting on this site and ( as one does!) I wondered how much time you spend at it.

Now I'm on here fairly often – and have been since the site first started. You will see my current number of posts on the left <.

I calculate that, at your rate of posting, I would have made around 17,000 posts in that time. Good grief man when do you find time to eat!

Norman

[JasonBModerator @jasonb]

Or do anything in the workshop

[AjohnwParticipant @ajohnw51620]

Surprise surprise I don't sit here all day and have no problem popping out – I often do sometimes part way through posting. No problem eating either. But yes I suspect I do post too much at times. Depends what I am doing at the time. Actually I usually disappear from forums i am on at some point. I was even missed on one. That should be a couple actually.

The workshop isn't doing much. I am part way through an immense reorg and tidy up. It's reached breaking point. I have been holding back on that waiting for a builder to knock one wall down and build another as then things would be a lot easier. Getting a builder to actually do it is proving to be a problem. I am slowly stirring myself to manage with the set up I have without the new wall. Looks like one lathe will have to go and later another which is in storage. There are still a few "bits" of of other tooling to go. A couple are pretty heavy. Getting the lathes right for selling might take time as I wont sell junk.

When it is sorted will I be making something. Maybe maybe not. I tend to machine things when I want them and feel like doing it. I have enough ideas to keep me going for a long time so it comes down to do I feel like doing it. First job when I can get at it easily will be some sorting on the Boxford. New bearings and probably some changes to the drive. Resite the inverter or get rid of it. Not sure which yet..

Just add there is a minuscule amount of oval bearing wear on the boxford. It tends to cause it to take a minute recut near the end if I run the same cut again. Infuriating.

I might decide to actually power the head lift on the Dore Westbury I might not. Much depends on if the motor I have is suitable. The power supply is bound to be useful at some point. The motor could go back on ebay.

I most certainly will rejig my dividing head at some point for the maidstone engineering plates and very probably change the worm and wheel as well.

3D printing and casting are closely connected for me. I do know where to get what I need now and have some of it. Unlikely to happen this year.

I do want to make a clock and have more or less sorted ideas on what I will do for that but still some to go. No shiny gearbox for me though. It has to keep good time.

I also tend to buy things I need for potential projects rather slowly. In that respect I have at least 4 on the go at the moment. Some may never happen.

John

–

Edited By Ajohnw on 03/08/2016 19:54:19

Edited By Ajohnw on 03/08/2016 20:00:25

[Steve SharmanParticipant @stevesharman33815]

At the risk of upsetting Neil et al. ( linking off-site) I have recently recounted my own mill table power feed project here and it may prove useful to someone wishing to try their own version. If nothing else, it highlights some of the pitfalls to avoid. The unit is not pretty but it works well and cost next to nothing.

Regards, Steve

[Michael GilliganParticipant @michaelgilligan61133]

Steve,

I doubt if you will upset Neil et al, but …

It would be nice if I had permission to view the thread that you linked.

MichaelG.

[Steve SharmanParticipant @stevesharman33815]

Ah! Sorry, I don't know how to sort that problem. I expect that non-members can only view the "General Chat" area.

Apologies to any who cannot access the article, I will remove the link if requested.

Regards, Steve

[JasonBModerator @jasonb]

Thats the case steve, non members only get to see the top couple of topics which include the general discussions. Easy enough to register though for those thinking off using a wiper motor as the power source.

The link can stay.

[Steve SharmanParticipant @stevesharman33815]

Gentlemen,

My sincere apologies to anyone who has wasted their time following my earlier link.

I am currently logging my locomotive build on my own website and I have written up my mill power feed on there in the tools and jigs section. If anyone is interested, you can link to the article here

If Neil or Jason feel this is inappropriate, I am sure one of them will remove this post.

Regards, Steve

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Steve Sharman on 04/08/2016 07:22:59:

… I have written up my mill power feed on there in the tools and jigs section. If anyone is interested, you can link to the article here

.

Great stuff, Steve … Much appreciated

MichaelG.

[Neil WyattModerator @neilwyatt]

We have no issues with forum members linking to their own blogs elsewhere, although it's nice to have things posted here

Neil

[here againParticipant @hereagain]

Havent seen anyone suggest a 90w 230v speed controlled sewing machine motor..Must be a reason -what is it?I have one looking for a use☺

[Author]

Posts