Author Topic: Oh Blimey I bought a CNC Lathe !!!! (Read 272730 times)

dawesy · « **Reply #525 on:** January 23, 2014, 06:16:33 AM »

just read this thread from start to here.
hats off to you sir, i wouldnt have known where to start. its good to see someone not giving up but persevering and overcoming the hurdles that come up.
top work

awemawson · « **Reply #526 on:** January 23, 2014, 06:41:27 AM »

Thanks Stuart, no major voltages involved, mild stuff really just horrendous data consequences if I'd fluffed it

Dawesy, I appreciate your kind words but I reckon you deserve a medal if you've just read it all

The battery float charge mod has had 24 hours of 'uptime' now and everything seems to be stable, so I've battened down a few hatches and will leave it a week or so before measuring again.

Andrew

vtsteam · « **Reply #527 on:** May 15, 2014, 09:40:08 PM »

Last entries about the battery backup -- so Andrew, what have you been making in the completed lathe?

awemawson · « **Reply #528 on:** May 16, 2014, 02:55:06 AM »

In all honesty Steve not a lot. I made up a batch of shouldered heavy duty washers, but even that was really playing. As you well know it was the journey rather than the destination that motivated me.

I still have to turn up a replacement for the ptfe sealing bush that feeds coolant to the powered tools, and one of the bearings in the motor for the powered tooling needs changing when I get time as it is rather noisy, but neither of these thing stop the machine, nor are they currently priorities. Farming type things have come to the fore with the season changing.

vtsteam · « **Reply #529 on:** May 16, 2014, 03:41:25 PM »

Andrew, knowing you, I think it's probably time to sell that smoothly functioning masterpiece of investigative restoration, and get a REAL piece of junk.

That one was really on the small side anyway! Do I recall a video of a lathe here somewhere on the forum turning a ship's crankshaft?

awemawson · « **Reply #530 on:** May 16, 2014, 05:43:45 PM »

Oi - stop it. Coming back here causing trouble

tom osselton · « **Reply #531 on:** May 17, 2014, 07:44:11 PM »

So just wondering what is the longest article posted on this site?

dsquire · « **Reply #532 on:** May 17, 2014, 08:12:32 PM »

Quote from: tom osselton on May 17, 2014, 07:44:11 PM

So just wondering what is the longest article posted on this site?

Tom

Follow this link and it will give you answers to some of your questions.

http://madmodder.net/index.php?action=stats

This thread seems to be at the top for members that are still active. We are still waiting while Andrew decides what type of widget he is going to flood the world with.

Cheers

Don

awemawson · « **Reply #533 on:** August 26, 2014, 03:08:53 PM »

Sorry to revive an old thread chaps, but I'm using this as a way of recording what I've done to this machine - a sort of blog I suppose:

Some of you may recall that I managed to pick up a very nice, apparently unused, 'Hydraulic Power Chuck' complete with masses of jaws. I never fitted it as when I came to remove the collet chuck that came with the lathe, I was a bit stumped as to how it came off.

As I was just playing learning to program the machine it didn't matter, wasn't at the top of the list, and I let it be.

To refresh your memory this is the chuck with its jaws:

awemawson · « **Reply #534 on:** August 26, 2014, 03:27:16 PM »

Now what had stumped me was that I knew that the Collet Chuck fixed to the main spindle with four M12 bolts, and the socket caps for these bolts were covered by the collet closer front plate, itself retained by a ring of M8 socket cap bolts. I'd removed the closer, removed the collet, removed the four M12 cap heads, and could NOT budge the actual body of the collet holder.

Yesterday, I awoke to pouring rain, and decided that being a Bank Holiday I'd actually get up in a more leisurely way than normal. So there I lay, drinking my coffee and going through my list of things that needed sorting, and this conundrum came to mind. Then, in a flash of inspiration it came to me

I'd always relaxed the collet before removing it, and on this lathe the collet is PUSHED to close onto the collet closer front plate, not pulled like a normal collet. This meant that the mechanism was in this instance PULLED backwards, as was the bit I was trying to remove (despite the power being off)

So today I had a couple of hours free as the sides of bacon I had to slice were chilling in the freezer. (Never try slicing bacon at room temperature, as it goes all over the place!)

So off to the workshop, CLOSED the collet, powered down, gingerly removed the closer plate that now was being pushed off), removed the collet and was able to unscrew the collet closer from the operating tube and remove the body of the collet

awemawson · « **Reply #535 on:** August 26, 2014, 03:34:12 PM »

Shortly after I had bought the chuck, I'd identified and sourced the correct adapter flange to fit it to the spindle nose, so in theory all that I have to do, is turn up and thread a draw tube adapter that takes the hydraulic draw tube at one end, and the chuck operating 'ring nut' at the other.

It involves some careful length measurement and probably won't happen for a few days

awemawson · « **Reply #536 on:** August 26, 2014, 03:35:56 PM »

Anyway it's progress, and I'm relieved to say that the adapter flange fits the spindle nose, which until today I hadn't actually seen

vtsteam · « **Reply #537 on:** August 26, 2014, 07:52:19 PM »

Nothing like going away from a puzzle for awhile in order to solve it. And mornings are the time for inspirations and solutions!

awemawson · « **Reply #538 on:** August 27, 2014, 04:31:41 PM »

Thanks Steve.

Just a little bit of progress today. I managed to withdraw the co-axial hydraulic cylinder chuck operating tube from the main spindle of the lathe so that I could measure it's diameter and pitch. That well known standard 74 mm x 1.5 mm

It unscrews from the co-axial cylinder, but to lock the spindle meant I had to have power on the machine and use it's hydraulic spindle brake. Upside was that the correct tubular spanner was in the bits that came with the machine.

I also measured the chuck operating nut that the other end of the adaptor will screw into - another nice standard at 53 mm x 1.5

So now I know that I need an adaptor with a female 74.0 x 1.5 mm thread at one and, and a male 53 mm x 1.5 at the other, with an outer diameter of no more than 78 mm. with the biggest bore I can get away with.

Just need to determine the exact length. Gets slightly complicated as the chuck needs a different length of movement to the collet chuck that I've removed, and the 'far' side of the co-axial hydraulic cylinder has a proximity switch checking the movement and determining if the chuck is locked on safely or not - so the length has to fall within fairly close limits.

My thoughts at the moment are to err on the long side of the male thread and adjust to fit.

Kjelle · « **Reply #539 on:** August 28, 2014, 02:32:35 AM »

Nothing like a standard, everyone should have his own!

Good luck Andrew, I've been following this from the beginning!

Kjelle

awemawson · « **Reply #540 on:** August 28, 2014, 08:22:19 AM »

Thanks Kejelle

Today I dug deep in my pockets and ordered a length of 4" EN8 steel to make the adaptor - I did have an end of 5" mild steel that was long enough but I prefer to have a slightly better steel for this component

awemawson · « **Reply #541 on:** September 04, 2014, 12:56:48 PM »

Well quite a bit of progress today. That huge chunk of EN8 steel arrived, and I decided before I started hacking it about, I would make up a functioning mock up from bits from the scrap box. So that I could adjust the length 'in situ' I decided to make a separate male and female thread, both unbored save for a 12 mm threaded hole so they would screw onto 12 mm threaded studding.

This way I can adjust it and check the chuck fully closes and fully opens while still operating the proximity sensor thus keeping the TX8-F controller happy.

awemawson · « **Reply #542 on:** September 04, 2014, 12:58:34 PM »

I started with the male thread, dug out a bar end of mild steel and started making swarf:

awemawson · « **Reply #543 on:** September 04, 2014, 01:00:39 PM »

Then I attacked the female thread. Stock this time was the end of a roller scraped from a paper mill.

awemawson · « **Reply #544 on:** September 04, 2014, 01:02:39 PM »

The two bits then screw onto a length of 12 mm studding, allowing me to adjust their separation in a 'suck it and see' fashion

awemawson · « **Reply #545 on:** September 04, 2014, 01:03:39 PM »

And then putting the hydraulic draw tube, my mock up, and the chuck together we get this:

awemawson · « **Reply #546 on:** September 04, 2014, 01:05:32 PM »

So tomorrow I hope to assemble this lot back in the lathe spindle, which will allow me to make adjustments and trials to finalise the length of the 'proper' adapter.

But first I need to make some tubular spanners so the bits can be tweaked in place.

vtsteam · « **Reply #547 on:** September 04, 2014, 02:23:11 PM »

me want to see tubular spanners.....

awemawson · « **Reply #548 on:** September 05, 2014, 06:15:43 AM »

Nothing complicated Steve - just heavy wall tube with projecting lugs.

So I started today by milling pockets in the female threaded part to match the big tubular spanner that came with the lathe

awemawson · « **Reply #549 on:** September 05, 2014, 06:26:48 AM »

This spanner fits 'up the spout' of the lathe and was intended to tighten the tube that couples the hollow hydraulic cylinder to the chucking device.

Next task was to fit the adapter on the spindle nose that converts the A6 nose to this particular chuck (A5) - easy task, but then I discovered that the bore through the adapter was a tad less than the spindle bore, no issue functionally except that the big tubular spanner won't go through it

But that's why we have lathes . . . . modify the spanner

Rather a lot of over hang here - but it's very thick walled tubing - I had to reduce it by 1.5 mm diameter

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Author Topic: Oh Blimey I bought a CNC Lathe !!!! (Read 272730 times)