Thread: New South Aussie Machine - Build Log 2010

Sorry Noel,in my dotage can't remember who's who.Neil is another of my "wards" he's a young bloke about 67 or so that keeps getting himself in hospital hence the mix up.Baz

Baz
Absolutely no need to apologize, your support over the past six or seven months has been worth gold.

Very glad to see that you have emerged from the shadows.

NOW - Get going with a post of your own - we would all like to see your efforts.

Don't worry about 'simplicity'in your design, etc, - everybody has to start somewhere, and I am sure that many people will get a lot of encouragement from your efforts.

Cheers mate!

Noel

Hi Guys
Well - after a 12 month batch of ill-health, I have finally gotten around to resuming my build.

The worst part about having to leave it for so long was that I found I had forgotten a great heap of stuff, and have had to slowly re-learn a lot.

Anyway - ta da (sound of trumpets blaring, etc, etc) - I have finally got the motors to move - always a thrilling event, as until they actually move, it is difficult to work out if everything is in the right place.

With a bit of assistance from some of the guys on this site, I worked out the speeds to suit my rack and pinions, and I am very happy to say that the mill moves VERY SMOOOOOOOTHLY - oh so satisfying!.

Not only does it run smoothly - but it is QUICK (maybe a bit too quick - might have to slow the motors down a bit - at the moment it can reach an unloaded speed of about 11 meters/minute).

I have used two LPT leads from the computer, and two B.O.B's. This did give me a bit of angst, because after installing the second port, the computer (running Windows XP) would not recognise it, and put yellow question marks into the device manager.

Anyway - long story, short answer - the port did not come with PCI drivers, and it is extremely difficult to find any one the Web. However, did eventually trace some down, andf after loading them, the problems went away. (If anyone esle is having similar problems,- and looking at CNCForum, and MachForum it appears to be a common issue - let me know and I can give you the drivers).

So - now to wire up the limit switches and home switches.

As far as the home swithes go - I have çribbed' from a site on CNCForum, and am using 'Hall effect' switches. (Cut the housing from perspex on my old machine, and a mate helped me put them together - Piccys below).

Anyway - that's the latest state of play, and I will post more as the machine develops.

Cheers, and thanks for all the support last year.

Noel

Very cool Noel I notice you've five gecko's in there. I can see four in use, so what's the fifth do?

Brad.

Hi Spidey
Four for the three axes (X, Y, Y2(A), and Z - two drives on the Y axis).
The fifth drive is for my future expansion into a fourth axis.
need to finish the basic machine first - couple more weeks - then I am buildinhg a fourth axis.

Cheers

Noel

Noel,

Excellent work there. Very nice and tidy. When you get a chance, my unit needs some TLC and probably retrofit to rack.

How did you go with the step setup. Did you manage to calibrate each axis accurately?
Is the last photo of hall effect switches?

/Michael

Mike

Yes - many thanks for the help.
I managed to calibrate each axis without any dramas at all.

And yes again - you have ot on the ball - the last photo is a shot of one of the Hall switches.
I milled out plastic housing and had some help fitting the switches and resistors into them. just as well - I'm not that good at soldering small finicky bits.

We tested the switches out after assebly and they all worked without a hitch, so I am looking forward to seeing them on the machine. Supposedly they are far more accurate than roller or vane switches, and have a much higher repeatability fraction than other switches. from memory, I think they were claiming on CNCForum that the repeatability was within something like 0.006mm - not bad if true.

Anyway - another 'toy 'to p[lay with, and something else to exercise my brain with.

Cheers

Noel

Hi all

Now that I look more closely at the photo of the Hall switch, the more çruddy'it looks.

I will take a better shot and post it as I think this is an interesting idea.

Cheers

Noel

Hi Noel,

You might want to switch the 2nd Y axis to B or C if you're going to get that 4th axis going next. The A axis is the norm for the rotational axis.

Brad.

More photos of the Hall Effect switches - still not good images.

These things are really tiny - the red spot is a 3mm l.e.d., and the tiny black square is the Hall switch. If you look closely you can see the two resistors underneath everything else.

The wiring was a bit of a bitch, but as I said previously, I handed that job over to a friend who is really good at soldering small connections.

Cheers

Noel

Whoops!!!!

Sorry - good idea if I actually post the photos.

Originally Posted by PsychoPig7

More photos of the Hall Effect switches - still not good images.

Have you tried using macro on the camera it should take a much better picture.

I have this type of home switches on one of my machines.

They work really well. The actual Hall Effect package is smaller than a grain of rice (excluding the leads).

Greg

Hi Greg,
Can all the limits be run off one pin?
I think it would have to be done on parallel rather than series if at all possible?