Building the Division Master and modding my RT

[NickG]

Nice 1 John, this makes it ultra clear for other people considering this mod. I really could do with a rotary table of any sort but one day will have one like this.

Nick

[Bogstandard]

Sorry about being a day late, but the weekend was a little too much for me.

So anyway, I got another bit made today, and it wasn't as straight forwards as I thought it would be. A couple of fixit jobs had to be done, all because I thought I had everything covered.

You know what thought did? He thought he had only farted, but in fact, he had s**t himself.


So it all started this morning, after I got back from taking Bandit for his run, he has to run, otherwise he gets left behind, as I am on my buggy.

I thought I had some 60mm ali bar to make this unit out of, but it turned out to be 75mm, and I wasn't going to waste material by having to turn it down that much, so I settled on a smaller piece, that was 2mm under my ideal size. But it won't matter that much.
So the first job was to part it down to rough length.

Building the Division Master and modding my RT


Following that, faced up to exact length and the spigot end that is going into the flange was turned on the end.

Building the Division Master and modding my RT


Followed by a 19mm drill all the way thru.

Building the Division Master and modding my RT


The boring out took a bit of time, but with lots of patience and plenty of lube, I got it to final size.

Building the Division Master and modding my RT


The now tube was flipped end over, and the 19mm hole was opened out to the required 21mm.
So that was the basic tube made, or so I thought.

Building the Division Master and modding my RT


It was tried for a rough fit, looks OK.

Building the Division Master and modding my RT


Then an assembly fit, spot on. I was getting very cocky by now, things were going great.

Building the Division Master and modding my RT


So just a roughie mark up where the access hole needed to be, and it was time for lunch. Bad move.

Building the Division Master and modding my RT


So duly fed and watered, I decided to carry on, instead of my usual beauty nap in the afternoon.
Onto the mill with it now, and I hacked a 10mm slot thru to roughly where I had marked it up. It isn't critical, it is only there for guiding the coupling down the tube on assembly and tightening up the grub screw.

Building the Division Master and modding my RT


This is where I needed my RT, to put the three holes in the bottom, but because it is stripped down, I used the PCD function of my mill DRO for doing it.
So the first thing was to get the hole in the tube centred up with the quill and the DRO zeroed.

Building the Division Master and modding my RT


This is where things started to go pear shaped.
I was just about to drill the third hole, and then realised I had fed the wrong data into the DRO, and I was drilling on an arc rather than a circle. The second hole I had drilled was way off position.
So all I could do, rather than making a new tube, was to accept the extra hole (it won't be seen), re-enter the correct data and carry on drilling the second and third hole. They ended up in their right places.

Building the Division Master and modding my RT


After that bodge up, I tried to fit a screw thru one of the holes from the inside. It was then I realised I hadn't allowed for the cap screw heads while boring, and they were catching on the inside of the bored tube, kicking them over at an angle.

So what I did, was to remount the tube back onto the lathe and from about 15mm in, I enlarged the internal bore, so that the screws would fit OK.

This pic shows the duff screw hole, and the enlarged bore.

There is something to be learned here, don't try to machine while you are tired, as I was. Not just for safety's sake, but you can easily make simple calculation mistakes, as I did.

Building the Division Master and modding my RT


So anyway, things turned out OK in the end. It is now awaiting the flange to be made, which is tomorrows job.

Building the Division Master and modding my RT


I'm now going to catch up on my sleep that I missed this afternoon.

Goodnight


Bogs

[Divided he ad]

Does the job John 


At least you had a way out of the bodge!   




Hope you manage to get what you want done tomorrow 







Ralph. (listening to a bit o' Elvis  )

[NickG]

Bogs, unfortunate error but no harm done really though. I often make silly mistakes when am tired but am just beginning to know when to down tools and go in now.

Nick

[Bogstandard]

Ralph,

You know what it is like here, one unexpected visitor, and the day is gone for me. I have to plan each hour I can be in the shop at the moment.

I'm glad you like the oldies   


Nick,

At one time, things wouldn't happen like that with me, everything would be checked and double checked, and very rarely would something be amiss. But I have to accept now that I am just not the same guy I used to be a year ago, and I now work to the best of my abilities. It is very frustrating at times.

But I am still enjoying what I do, and that is the only thing that matters now.


John

[NickG]

John, that is exactly right, enjoying it is the only thing that matters and it's great to see you back in the shop, still turning out brilliant work and writing brilliant articles.

I think some of the loco brigade at our model engineering club sneer at me at the fact I've got a fair sized lathe and milling machine and mess around with piddly little engines. Maybe they think I should be blindly following the plans and machining castings to build a 5" gauge loco that's been done a million times before. I appreciate that there's a lot of work in them and some excellent workmanship but I get more enjoyment messing around with small scale things and working out designs for myself. It also lets me see projects to completion (although not quickly), with only a few hours a week of workshop time there'd be no point in me starting a huge project - it wouldn't be finished until I retire!

Nick

[kvom]

I had a bigger bonehead move yesterday  although it somehow turned out OK.

I was CNC drilling some 3/16" through holes (4.76mm) in a piece of 12L14 3/4" (19mm) thick.  Except I "forgot" to set the drill height above the surface.  So I got a rapid move (~50ipm) straight down at 1400 rpm.  Somehow it punched right through and didn't even break the drill.   

I can't claim fatigue as it was the first work of the day.

[John Stevenson]

I had a bigger bonehead move yesterday  although it somehow turned out OK.

I was CNC drilling some 3/16" through holes (4.76mm) in a piece of 12L14 3/4" (19mm) thick.  Except I "forgot" to set the drill height above the surface.  So I got a rapid move (~50ipm) straight down at 1400 rpm.  Somehow it punched right through and didn't even break the drill.   

I can't claim fatigue as it was the first work of the day.

Now you know your speeds and feeds for the rest of the job. 

[madjackghengis]

I had a bigger bonehead move yesterday  although it somehow turned out OK.

I was CNC drilling some 3/16" through holes (4.76mm) in a piece of 12L14 3/4" (19mm) thick.  Except I "forgot" to set the drill height above the surface.  So I got a rapid move (~50ipm) straight down at 1400 rpm.  Somehow it punched right through and didn't even break the drill.   

I can't claim fatigue as it was the first work of the day.

Now you know your speeds and feeds for the rest of the job. 

Hi John, I have to support John S. as to the feeds and speeds, it ought to go pretty fast that way though.
nice looking pieces going together, makes me look forward to the day I get on the ball on that job for my rotary table. mad jack

[Bogstandard]

Sorry I didn't get this finished yesterday, I nearly got it done, but not quite, so I finished it off today.


The final part to be made is the stepper mounting flange. I made this out of a bit of 12mm thick ali gauge plate.

First off was to get the top and bottom parallel and to the right size.

Building the Division Master and modding my RT


Next off I machined one of the untouched sides sqaure to the two finished ones, then it was stood up on that end to have the fourth side brought down to correct size.

Building the Division Master and modding my RT


This is it showing the four square finished edges.
Becasue the stepper actually has slightly tapered edges, I made this to a nominal size as shown on the sketch.

Building the Division Master and modding my RT


The next job was to machine off the anodised surfaces and bring it to 8mm thick using my large flycutter.

Building the Division Master and modding my RT


After that, I found rough centre, and marked a circle to 1mm under what is required. This will allow me to blitz to this mark, then take it steady after that to bring it to size.

Building the Division Master and modding my RT


Using a range of drills, most of the excess material was got rid of, much quicker than boring it all the way.

Building the Division Master and modding my RT


For me, it is easier to bore using my mill, purely because I have a power feed on the Z1 axis.

Building the Division Master and modding my RT


Even though I only have an Imperial boring head, because I have learned to work in both standards at the same time, I find I can usually get close enough to what is required.

Building the Division Master and modding my RT


Not bad, only 0.01mm (0.0004") out.
That will be just fine, as the Loctite requires a bit of space to work.

Building the Division Master and modding my RT


The tube fitted just right, a nice sliding, but not sloppy fit.

Building the Division Master and modding my RT


The next bit were the four holes for stepper mounting. As I mentioned earlier, the info sheet with the stepper didn't match exactly, so I resorted to manually measuring it.
Because I had made the plate spot on size all ways, it was a dead easy job to use an edge finder on two sides to find the first hole centre, then it was just a matter of moving the plate around, push up to the stop and drill. All holes ended up spot on in line with the ones in the stepper.
It always pays to spend a little more time getting your base sizes correct.

Building the Division Master and modding my RT


It was exactly the same for when the corners were rounded over, set up the first and the rest follow suit.

Building the Division Master and modding my RT


The finished mounting plate.

Building the Division Master and modding my RT


Everything fits OK.

Building the Division Master and modding my RT


Before I could progress any further, the RT had to be completely built up.
Correct greases and oils used in the right places, and the thrust washer underneath adjusted to give no drag or backlash.

Building the Division Master and modding my RT


The reason for assembly was so that I could get the just made flange in approximately the right position in conjunction with the tube.
The worm was engaged using the cam arrangement, and the parts marked up before being removed.

Building the Division Master and modding my RT


Some fast acting, but high shear strength Loctite (clone) was used to join the two pieces together.
I clamped it up in the vice, and went and had some lunch.

Building the Division Master and modding my RT


It was rock solid when I got back, but for a belt and braces measure, I drilled and tapped four 4mm holes at the joint between the two. Grub screws with a little more Loctite were inserted, making sure they were below the surface when tightened.
There is no way these two are going to come apart in normal use.

Building the Division Master and modding my RT


So the assembly was finished off, and the whole lot bolted to the mill table in the normal RT permanent position.
Once everything is fine tuned, I will put a piece of metalic tape over the tube access hole, just to stop swarf getting in there.

Building the Division Master and modding my RT


This is just a quickie demo.

On the third move, I noticed that the motor strained just momentarily, I think I have the worm a little too tight against the wheel, but if that is all that is wrong, I am very happy with it.

This is just the way I did things. There must be dozens of other ways to mount up the stepper.
Also you would have to take into account the sizes and shapes of the bits you will be trying to join together, so don't follow my actions religiously, you will most probably have to make the sizes to fit what you have got in your hands.

Hope you enjoyed the journey.


Bogs

[Divided he ad]

Nice...   


I'll have a look see next time I'm over. And see if I can't get a  push of the odd button or two under tuition     



How big is that drill bit      






Ralph.

[Spurry]

Great job !!

Thanks for the inspiration.

Pete

[spuddevans]

Great write up as usual Thanks for documenting this. I too have a rotab that I will be converting to stepper control, so I am bookmarking this thread as a reference.



Tim

[NickG]

Really professional job that John, works brilliantly. Thanks

Nick

[John Stevenson]

How big is that drill bit      

Ralph.

That's not big,

This is big 



John S.

[DeereGuy]

Nice job there John.  Glad to see you have it up and running.

[Divided he ad]

That's not big,

This is big   

He says as he slaps it on the table and photographs it!!!     





Couldn't resist 




Ralph.


P.S. No size ref' it could be a little tiny model of one!

[John Stevenson]

Not sure what size it is, it started life as a 5 Morse taper which has enough meant on the shank to convert it to R8

You can often get these at car boots for peanuts as they don't think there is any life left in them but in fact you want just the worn out stub.

John S.

[Bogstandard]

Ralph,

I don't look at the drill size when working in the rough, I just use one that is big enough to get rid of excess material.

The one I used was from a slightly larger 'blacksmiths' set, having a 3/4" shank rather than the standard 1/2". I have had these for a fair while now, but only just starting to use them in anger. I could use them on the mill in a collet, but I had no chuck large enough to hold them in my lathe tailstock. But RDG came to the rescue fairly recently when they started to sell these, which match my other hand tight chucks, and the quality is great for so little money. 6th one down, 5 to 20mm keyless.

http://rdgtools.co.uk/acatalog/3MT_Keyless_Drill_Chuck.html

I also treated myself to an R8 one for the mill at the same time and price.

I thought you would have noticed them on my drill rack when we were in there the other weekend.

Using large drills can save you hours of machining time, by getting rid of excess material very fast before final boring.

John

[NickG]

The only big drill I have is a 3MT 1" and I love it! My grandad must have sharpened it as with about 1/4" pilot hole it'll go through anything - if the time ever comes when I need to sharpent it I'll probably cock it up though!

[Bogstandard]

The larger they get Nick, the easier they become to sharpen, as they are much easier to see what you are doing. If pushed I suppose you could even do it with an angle grinder.

John

[NickG]

True. I found that out last night. I tried a drill that made a horrid scraping noise on some stainless, it looked ok but had to try sharpening the smaller one 3 times before I got it to cut acceptably. Ended up putting more of a point on it and that seemed to work.

I've got a bench grinder, might be able to do it on that, not sure whether the drill is too big actually suppose it should be ok. I've got a cheapo drill grinding jig but it's a PITA to set up and it really needs careful adjustment for each different size of drill so just do it by eye now!

Nick

[madjackghengis]

Hi John, I took a gander at the video, after going through the log, and it looks great, I know what mine should work like when I get to doing it up, and I can't say I've seen better from a rotary table, and what yours does will suit my needs perfectly.  Now my only choice is whether to build or buy the electronics, very nice job all in all, and fine performance.  I don't know how common the six by 48 belt sanders are there, but they are very popular here, and they have a nine inch sanding disk, usually, which goes dull with its first use, usually, unless you're working wood.  I was replacing the bearings on mine, and realised the shaft being five eighths, and a nine inch disc grinder having five eighths eleven threads, I threaded the end of the shaft, pressed a shrink fit shoulder on it, and replaced the aluminum disc for sandpaper, with a nine inch grinding disc, and have used the first disc for a couple years and it's still in good shape, and will flat out eat steel at the edge, and at the same time, flatten and leave a fair good finish on steel, when pressed against the face of the disc and the disc remain sharp.  It will dress up drill bits two and a half inches and larger with no problem, and it doesn't move about like a disk grinder lying on a table when trying to use it as a grinding wheel.
   All in all, a good build log, great expose on the division master to start with, and well managed assembly and machining of the parts to make it work, nice job all around.  I hope you get many good years of use out of it.  mad jack

[ieezitin]

John.

This was a great build; I thank you for showing it.

It makes me smile to see the extra effort you spent on putting the grub screws in on the flange where you had previously sealed it, when this piece of equipment gets handed on and the guy opens it up for whatever reason he should recognize the little quality touch.

God bless,     Anthony.

[arnoldb]

Good going John; excellent build log as always as well.
I like the way the controller software accelerates and decelerates the rotation near the start and the end.

Regards, Arnold