# The life of an old mill(K&T 2HL)



## MrCrankyface (Nov 25, 2019)

Hello everyone!

Been posting some of this machine on another machinist forum but figured I should post here as well.
Always fun and education to have more input considering that I'm very much an amateur at these things.
I consider this entire machine an ongoing project hence why it's here as a members project.

*WARNING, I LIKE TO POST A LOT OF PICTURES *

Long story short, I've wanted machines that could work metal ever since I was in the early teens, I like making things simply put.
16 or so years later I finally had the funds and space to turn my dream into a reality.

I had been looking at various ad sites for a while and eventually this 1947 K&T 2HL showed up for aprox $600 so I went and picked it up as fast as possible.
Weighing in at around 2600 pounds it's a bit of a handful for someone with no real equipment. The seller helped us load it up on the trailer I had borrowed.



Had a friendly contractor working in the area help me lift it off the trailer with his digger but getting it the rest of the way into the garage was a bit of an adventure..
Drove our little golf in and attached a chainblock to try and pull it in, which often resulted in the car sliding rather than the mill...


Eventually managed by very carefully hoisting the rear up and letting the jack act as a dolly of sorts ontop of some scrap plate.



Here it sits with my entire 'arsenal' of tooling in the background. 
What followed was what felt like an eternity of cleaning to get rid of old grime, loosening seized components and just generally trying to understand my first ever milling machine.


And here's my first "real" project with it.
I had done some tiny milling before but here I milled out all the "teeth" on the bottom thing and milling a bunch of other stuff to square and size.
The whole thing is a manual splitter for firewood
Sure, you could do this with an angle grinder but where's the fun in that?



After using it for a while I decided to do a small teardown since I was constantly worrying how the ways and oiling systems looked underneath.
It is after all 72 years old.


On top of the knee ways you have a saddle for Y movement and also Z axis rotation(ie the entire X table can rotate).


This is one of the nicer looking parts... Lots of sludge to remove and the oilwicks were .. Let's say they had passed their "best before" date.



Here's the little X screw, mid-cleanup.


I also started going through the vertical head that would every now and then let out black goo through the spindle bottom..
It was filled to the absolute brim with grease, most of it looking to be from the early 1800's(Ok, maybe not that old)
I took a whole lot of fistfulls of grease out of it...


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## MrCrankyface (Nov 25, 2019)

Here's almost all the parts that go into the vertical head attachment, cleaned up and nice. Most things still in good shape.


Greased up and re-assembled, ready for install.


Whole machine is starting to look a lot better, besides the worn paint.
I have also started installing a DRO here.


With a decent working matt it was a pleasure to play around here!



Sometime after this I made a bad mistake as I was testing out the overtravel stops...
One didn't work.
When it was supposed to trip and turn the powerfeed off, it instead jammed and caused the entire powerfeed gearbox to bind up and shatter the weakest link...
This is the input gear to the entire knee gearbox, controlling all feeds except rapid traverse.



Here's the powerfeed gearbox taken out, quite the procedure.
The above gear sits on the backside of this.


I did my best to repair my mistake but without the proper tools and knowledge, it never became 100% good.
I welded on material where the teeth were missing and cleaned it up on my mini-lathe.


Cut the teeth back out with a home made tool, basically a horizontal flycutter I guess. Ground the HSS bit as close as possible to the orginal tooth shape and used a 3D printed indexing plate.



The gear didn't come out 100% good but it worked pretty well for quite a few weeks, probably closing in on 80h of actual work.



During those 80h I managed to finish my DRO install, just a "cheap" asian import DRO but works well enough for an hobbyist amateur.


All the brackets cleaned up and painted.
I'm big into re-using materials. Most of what I've used here is scrap that was going to be thrown away or had already been discarded.
Feels good to not let more stuff go to landfill and also tends to be cheaper.


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## MrCrankyface (Nov 25, 2019)

Enter ... Stepper motors and CNC controllers.
I'm going to use the Mach3 software which needs a dedicated PC for it.
The power supplies and stepper drivers were bought but the rest have just been lying around for years.



About halfway wiring everything together, took me quite a while with lots of pauses, trying to figure out what goes where and why.


Finished all the wiring and it should pretty much be a CNC controller by now.
3 fans in the front suck in air through the filters and 2 fans in the back throws it back out.
This hopefully keeps the box slightly pressurized so it doesn't suck in dust through small leaks in the box.



Prototyping up some motor mounts I started with paper templates, later moving on to 3D printed templates of my designs.
Rather find flaws on a easily reprintable piece than a piece of metal I've spent all day on. 
	

	
	
		
		

		
			






Lots of hours later .. Bugs ironed out and remade everything in mild steel.
Left is Z and has a torquier(is that even a word?) motor, right is the Y axis.



Simpler holder for the X axis. Z and Y became overcomplicated due to my lack of experience designing things like these.



Still mostly using old scrap to make these things. Got a few of these old pipe lids that I managed to use up making motor plates.


Voilá, one CNC almost ready to run! 
	

	
	
		
		

		
		
	


	



Feeds perfectly now. You can mill "as normal" by just jogging it with a wireless keyboard or you can send it a full program to do more advanced manouvers.
Keep in mind it's still using the original screws with tons of backlash.
The software can compensate for that backlash up to a point but I'm not expecting thous here.
Screen on the wall can show both the hidden raspberry and the CNC computer, just select input depending on what you're doing.
The wireless keyboard on the worktable is to the CNC.


I also dabble in making youtube videos so here's a summarization of the project up to this point:


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## Martin W (Nov 25, 2019)

Excellent!
Cheers
Martin


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## Boswell (Nov 25, 2019)

Welcome to the forum. Thanks for the pics


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## NCjeeper (Nov 25, 2019)

Man I wish I could find a decent K&T for 600 bucks.


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## FOMOGO (Nov 25, 2019)

The universal table is a great feature, and nice job on the CNC conversion. Thinking your going to want some sheet metal covers (clear lexan would be cool) on your belt drives to protect them from swarf. Welcome to the forum, and looking forward to watching your project progress. Cheers, Mike


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## markba633csi (Nov 25, 2019)

Very nice conversion- you have been busy!  As to the broken gear earlier, a better repair would be to machine off all the teeth and find/make a new spur gear with the center cut out, then pin the two together and braze or weld
Mark


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## MrCrankyface (Nov 26, 2019)

Thanks everyone!

*NCjeeper:* Not sure if this qualifies as decent. The ways are VERY worn down 
Want to give scraping and rebuild a shot but currently got too many projects to go that route.
*FOMOGO:* Guess you're in for a treat! 
*markba633csi:* I considered going that route but the gear is nonstandard and I had a hard time enough just making those 3-4 teeth with a broken mill so making an entire ring would've been horrid. Sending it to a shop wasn't an option due to the cost of it which was my only other alternative.

Pictured is two driveshafts driven by the one and only motor in the mill, they're responsible for powerfeed and rapid traverse respectively.
I removed the bevel gears here to make it stop driving the knee and feeds entirely since that gearbox doesn't need to turn anymore, reduced both noise and load on the motor.



I then started looking into making a cover for the Y and Z motor so they'd stop getting chips on the belts. Originally I was just going to put a plate here that'd double as a tool area ...



But then I kinda let my creativity loose on this thing... I believe this is the point where things start getting out of control. 
My DIY sheet metal bender also didn't quite like this 1/8" plate. 



Attached a foldable 'desk' area.



Overkill? Probably. But fun!
Switches from left to right:
On(impulse) for PC box.
On/off for CNC PSU's(if driver sees an error you need to reboot it to reset alarm).
On/off for lights(there is none yet).
Manual-0-auto switch for cutting liquid pump.
Manual-0-auto switch for spindle.
Emergency stop(Yeah I know this isn't correct kind of switch for this purpose).



I've always been a bit annoyed by how far chips can fly and with the machine "automated and unreliable" I'd prefer to have some kind of shield between me and the machine.
I could've gone the 'easy' route and just had something around the spindle but I didn't like that idea since it might hit the work piece/clamps and so on.

I started with a rough concept and ended up around here somewhere.
The main requirement was to shield from any chips aimed "out into the room" and also fold up to minimize space when not in use.


It was going to be manual until I realized I'd be too lazy to use it .. So automation here we go.
Plastic sheet that will get raised up to bea couple of inches above the spindle.
With the plastic sheet down it stays below the top level of the table, incase I have to mill something that extends the table.


Here's a look of one sides mechanism. Another motor closes/opens the doors.


Tore down the control panel and sanded the middle plate while painting everything around it.
Tried to get that "brushed aluminium" look on the panel.
Also added a third switch for the shields/windows in/out.


Everything except the plastic windows is now mounted, still need to start running wires.


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## MrCrankyface (Nov 26, 2019)

I decided that it was an absolutely horrible idea to have the CNC screen so far to the side since I need to look at it more often than I thought ...
Found a cheap replacement monitor(used) and of course over-engineered the heck out of the new mount.


A small geared DC motor runs a winch through a pulley system to raise and lower the screen with the flick of a toggle switch, it stops at either end.
A small string lifts the "shield" when it's down in "use mode".






This allowed me to move the smaller screen to the machine instead.. But I still want to keep the DRO on there due to the backlash in the screws.
Just need to make some kind of bracket so I can mount both.


First time welding steel with TIG, a lot of fun! 
	

	
	
		
		

		
		
	


	






Just need to plug them back in now but might move computer box first to a better location.


PC box has been mounted to the wall to keep it free from chips.
It has a flex hose going to the control panel for all the wiring.


Rewired inside the PC box. All DC 0V are now going to one point in a star configuration. This is to make sure there's no floating ground potential between the different PSU's and simplifies wiring.


Control panel also has a bar for connecting all grounds. Should be plenty of space for potential expansions(feed hold/run for example).
Both this and the other connection bar are sitting on plastic spacers, insulating it from the metal around it.


This brings us almost up-to-date on this project.
I'd say I'm fairly on track of my original idea of "let's spend one week and just throw on some stepper motors and run it".(it's been over 3 months)


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## Janderso (Nov 27, 2019)

Incredible.
To me, you are like Einstein.
I bow to you sir.
Did I miss something? Are you using ball screws?


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## MrCrankyface (Nov 29, 2019)

Thank you! I am not using ball screws but I hopefully will in the future.
I'm currently using the softwares backlash compensation and it works alright for light cuts and drilling. I wouldn't try to take a heavy cut tho, I'm sure the cutter would bite and pull the table/saddle off position.

Slowly making progress. Been so tired this week and wiring isn't the most exciting thing to do ...


I've started hooking up a VFD, gave it a testrun with a regular rubber cable and it works alright.
Pulls my RCD on the first startup though so I need to get that replaced to a type B apparently.
It's pretty neat seeing the machine start up smoothly over 2-3 seconds instead of just pulling a contactor and slamming into full speed..
The white contactor above will be controlled from the control panel to be able to shut the VFD on/off or let Mach3 automate it.
Waiting for the RCD to be replaced(hopefully today) and also some shielded cable between the VFD and mill to avoid electrical interference.


Found this in a closed box on the back of the mill when I was hooking up the VFD, look at that blue cable!
Not sure what's happened here but part of it has been overheated and insulation was VERY crispy.



Current-ish overview.


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## MrCrankyface (Dec 7, 2019)

Progress is slow with lots of stress at work and autumn darkness isn't exactly boosting my energy either but here's what I've gotten done.

Had to install a seperate RCD for the VFD as the old one was no bueno.
It's now possible to start the PC, CNC PSU's and spindle from the control panel.
There's also the emergency stop to the far right which kills CNC PSU's and spindle.
Also added a USB receptacle for transfering cad/gcode stuff.


Everything is now prepared for LED lights around the spindle and some kind of cutting fluid pump.
I'm still not decided on wether I should go with just cutting fluid or have the option for pressurized air/mist cooler setup as well..


I've returned to working on the shields/doors which is starting to become more and more of a turd, no matter how much I polish it, it's still **** at the end of the day.
I will need to remake it completely in the second prototype but this will have to do for the moment as I'm out of energy for this part.
The window lifters work great but the door open/close is a nightmare, not to mention the lack of proper cable paths.
Cable attachments are very temporary since it will all be replaced.
For now I have disconnected the open/close mechanism and will do that manually.


"Shields" in versus out:


There will be a seperate piece in the middle but haven't started designing it yet.


Short vid of the lifters.


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## Tim9 (Dec 7, 2019)

The K&T mills are very nice mills. I think they are still in business but not making mills anymore. I forget the details but remember investigating KT a few years back because one showed up locally. It too was a huge bargain. But I had to pass because it’s just too big of a machine for my limited space. 
But they really made great mills. Not a machine that shows up a lot but very much a stout mill. 
   FWIW... if you ever need to move heavy stuff again...4 short lengths of 3/4 or 1” black iron pipe makes it real easy to roll stuff if you have a smooth concrete floor


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## MrCrankyface (Dec 17, 2019)

Yeah this is pretty much a mini version so works in a garage. The bigger brother(2H) would be difficult to fit! 
Also pretty sure the concrete slab wouldn't like the weight.
Good tip!

I've come to the conclusion to remake the doors and lifters ASAP.
Got plenty of help with the 3D-CAD re-design from my new assistant.



Meanwhile I did a temporary solutions. The tinted window(protective plastic still on) is just placed into two holders, this locks the doors into position.
The switch on the control panel can raise/lower the windows at any time but it's not 100% reliable so sometimes you need to push one of the windows a bit.


Finally also got the control panel back in place.


I will let the machine produce one of the parts from plastic(HDPE I think) so this required me to finish the VFD install. Now the software can directly control the VFD's output so for easier work I can just leave the mill in top gear and let the VFD control the speed.
I've activated backlash compensation in Mach3 but either it's set wrong or my backlash is just too big to compensate because it doesn't come out right. Either way it's a constant learning experience!


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## MrCrankyface (Dec 31, 2019)

Starting working on this accessory attachment for the head the other day, using whatever scrap I had lying around.. 
	

	
	
		
		

		
			




Kinda going off the top of my head here as opposed to my usual routine of cadding everything up first.
Tried to get a rough shape of what I wanted first, limited by the material I had.


The horizontal plate was a bit flimsy despite being almost 1/4", it's from an old sign so probably very low grade aluminium. Bent this 'skirt' for it to also encase some lights.


Still struggling with AC TIG, I'm fairly sure a big part of the problem is not making sure the material is clean enough as it was impossible to keep the puddle clean.


Here's the 'final' outcome. The aluminium block can be raised and lowered with the red lever above to adjust for different size and length endmills.
The different tubes are air and cutting fluid, selectable from the control panel by one of the switches.
The block is a bit oversized at the moment but I will leave it like that incase I come up with some other ideas in the future.



This is the air supply I cobbled together, re-used stuff hence why the pressure meter only goes to 6 and not 10 bar as the compressor delivers.
After the pressuremeter is an electric solenoid and a pressure regulator.
Currently the solenoid gets a signal from the control panel directly, I might let the CNC control this itself in the future but haven't decided yet.
When in use I will connect the hose to the bottom of this rig.


The cutting fluid comes from this "tank".
Re-purposed can(what's the proper english term here?) with a level sensor(turns off pump is too low and gives alarm on the control panel).
The pump is a quite small diaphragm version but seems to do the trick, it's also controlled from the control panel for now.


The table drains into this outlet, I made a new piece to fit here so I could use a regular hose back to the tank.
It seals with an o-ring between the plate and the casting.
This was the first time I ground a HSS tool for putting in o-rings, spun the plate up in the lathe and just went for it.
Definitely fun trying new things!


I also managed to figure out the backlash issue! I measured the backlash 2 inch intervals along entire X and Y.
Not only were my steps per mm not calibrated well enough(It moved 607mm when I called for 600) but X-axis would also lose position sometimes.
I tracked the loss of position down to the big pulley not staying put on the shaft with only the grub screws so I opted to secure it with a through-pin.
Managed to slide-fit this bearing using just a small endmill, sure saves time when it's not a critical fitment!
	

	
	
		
		

		
		
	


	





The part I've been trying to mill belongs to the new door-opening assembly.
Definitely an overcomplicated solution, but fun and I'm learning a lot by doing it.


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## MrCrankyface (Jan 15, 2020)

Managed to make some filler rod holders using the machine!
The thick white slab is machined in one go, terribly convinient. 
	

	
	
		
		

		
		
	


	



I think total runtime was maybe 10 minutes, excluding tool swap time between drill and endmill.
The tubes are regular plumbing pipe, roughly 1.5" diameter.

Also started hacking together a cover for the X motor, probably among my worst welds I have ever made.
Between the lack of gas and extremely thin sheet(23 thou), it was overall a horrible experience but I was impatient to get it done.
Some grinding and paint will fix it up.

I started over on the doors, replacing the square tubing, painted the steel sheet and redesigned every plastic piece in one way or another..
Assembly is now smooth as butter and functions as it should.

Here's the completed setup.
The doors rotate out and raise the windows at the hit of a switch whilst the middle window is on a hinge and manually operated.
I skipped the doors folding in half, simply wasn't worth the mechanical complexity that it caused.
I also simplified the middle window with just a hinge, which works out well as when it's folded down, it protects the control panel really well whilst still letting you operate the switches.


Here's a short video earlier in the process, of one door opening and raising windows.


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## MrCrankyface (Jan 28, 2020)

The saga continues.
After testing the flood cooling a bit I realized there was a middle ground I was missing between air-blast and flood...
So I made and revised the cooling system with these pieces, lathed most of it from bar stock since that's what I had on hand.
The cooling pump will pump when either solenoid is on, one solenoid goes to flood and the other goes into the air-blast pipe, effectively making a mist-feature.


I finally went ahead and marked up the panel as well and added a small selector switch above the main control for coolant.
It will light up airblast/mist or flood depending on what it's set to, then you activate it with the bigger toggle switch.
Hopefully I can let the CNC activate this itself later on.


I've been letting it do some aluminium work and it's been a crazy amount of learning.
All tool paths has been generated by fusion360 and is hands down the most complex thing I have ever tried, although I'm sure it's absolute peanuts to people with the slightest bit of experience! 



I believe the piece came out quite nice overall despite the little mistakes here and there.



It's going to be a light fixture after some more work on it.

I've already started looking into ball screws as the current screws are highly limited when it comes to rounded paths.
Vibrations and end mill rotation can sometimes cause it to wander into the backlash area and remove material where it shouldn't.
This requires you to run very conservative cuts to avoid it.
This isn't news just stating the obvious 
However ball screw conversion has to wait as this project has taken up too much time from other things that need doing.

What's left to do currently is mostly wiring jobs and screw the panel back into place.
-"error" wire from the stepper drivers so the entire machine stops if any of the stepper drivers gives out.(Almost need to swap pants when one driver faults and the rest keep milling...)
-Wires to each home sensor(I realized it'd be quite convinient to be able to set a "machine home" automatically)
-Extra wire to VFD to make sure it goes into FWD mode. Currently I have to climb behind the mill to go from "neutral" to fwd.

But once this is done it should be a very capable machine even without the ball screws!


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## MrCrankyface (Mar 10, 2020)

Finally got this video cut together.
It's part 2 out of probably 4, sums up a lot of the process better than I can word it.


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## MrCrankyface (Jun 16, 2021)

If anyone is following my threads, you can probably notice I'm all over the place right now.
Since the belt on the Z motor broke some days ago, I started thinking about regearing it.
The Z has always been a weak point, the motor often stalls out and moving it slowly (<10mm/min) was a sure way to cause it due to the axis being a bit sticky.
Following the datasheet speced at 60V AC, I've been calculating the torque over various gearings.
Torque in Nm on the Y axis and feeds in mm/min in the X axis.
Looking at this new graph, clearly a gear reduction of 4(yellow) to 5(light blue) times is MUCH better than the current 2:1(orange), I gain torque across the entire spectrum.
A 5:1 direct gear reduction would probably come out pretty huge so probably need to do a 2 stage gearing.
My goal is to make the Z speed reach 800mm/min, anything above that would be a great bonus, currently it maxes out at 300mm/min.


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## FJsapper (Jul 8, 2021)

Great work! I’m considering going down the same path potentially. How intense would the ball screw conversion be? That’s one of the issues that gives me pause.


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## MrCrankyface (Jul 8, 2021)

FJsapper said:


> Great work! I’m considering going down the same path potentially. How intense would the ball screw conversion be? That’s one of the issues that gives me pause.


Thanks!

I haven't landed there yet but I it will definitely require modification of both sideplates and somehow making space for the nut inside the saddle for the X axis.
Y axis should be simpler, bolt a plate with the bearings to the front and shove it through like the old one.
Z I haven't yet started thinking about and don't really know how it looks in there.
Will definitely update once I get there. 

Hopefully I can start working on it in a few weeks.


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## MrCrankyface (Jul 9, 2021)

I'm such a scatter brain. Took me until today to realise I forgot to post part 3, which by now is old but if anyone likes watching youtube, here's the video.


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## MrCrankyface (Jul 14, 2021)

I've been giving this a fair bit of thought before arriving at this solution...

I realized going with a 1:5 ratio or larger would need a really large second pulley, or gearboxes, or a 2 stage gearing.
I really like the idea of doing the gearing in one single stage, without gearboxes.
This limits complexity which should keep down losses and points of failure.
However, a large pulley is hard to find and quite expensive.

So what I'm going to try is having an aluminium hub of sorts, which I can bolt different 3D-printed pulleys on!
After spending quite a few hours trying to model up a pulley in CAD, I think I got it nailed down!
The belt matches the 192 tooth pulley pretty much perfectly all around!



I started with a 104mm cylinder of aluminium and made this hub, the DRO on the mill helped me locate all the holes for bolts which then got drilled, chamfered and threaded.
And yes, I know my lathe needs a deep cleaning.




A quick prototype print was then used to verify that the hub of the 192 tooth pulley will fit on the hub.
The pulley itself is a very snug fit on the shaft of the mill, hence why I've barely put it on.
I'm both afraid and hoping it's not going to move anywhere once I push it all the way in. 



Currently printing the "real" pulley, a 18 hour long print.
I suspect I will have to redesign the Y unit to the right as well since the Z gear will probably collide with some parts of it.


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## markba633csi (Jul 14, 2021)

You should get (make/buy) an indexer (mechanical/electronic) then you could cut your own aluminum timing pulleys
-M


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## Weldingrod1 (Jul 14, 2021)

Here's a 3mm pitch pulley I printed for a swerve drive.
	

	
	
		
		

		
			





Sent from my SM-G892A using Tapatalk


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## MrCrankyface (Jul 15, 2021)

markba633csi said:


> You should get (make/buy) an indexer (mechanical/electronic) then you could cut your own aluminum timing pulleys
> -M


It's been on my wishlist for years by now! I want a "real" indexer so I can convert it with steppers and use both as a 4th axis and for gears and all kinds of stuff.
I think in this case 3D printing still wins though, if it lasts, since just the stock for this large pulley would be quite some $$$.


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## MrCrankyface (Jul 16, 2021)

It ended up taking almost 24 hours to print this but it came out great!



I did a real quick hackjob of fitting it and also had to cut into the Y mount on the right due to the large diameter but it works great!
The motor pulley is missing a flange and there's a slight misalignment so the belt wanders a bit but should work until I tear it all apart for renovations/restoration of the slideways and installation of ballscrews.



Took a quick video of it.
Managed to get the speeds up to 450mm/min and still be reliable, with a much higher acceleration than before.
Above 450mm it sounds like the stepper is revving too much, might give 5:1 a try instead of this 6:1 ratio.
The idea is to run 6:1 for a while to start with, should give me more of an idea if I really need more speed or not, previously it's maxed out at 300mm/min so it's still a big improvement.
When it comes to low speed movements it's absolutely amazing, I can go 1mm/min without the slightest stutter or tripping the overcurrent alarm!


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## MrCrankyface (Jul 19, 2021)

As I've mentioned before I'm just waiting to have the time and resources to completely overhaul this mill.
This will be a full on renovation, tear it all to bits for a deep cleaning and repaint along with scraping the ways and such.
Obviously this will be a massive task.
Before I do this I'm trying to come up with a comprehensive list of all the things I want included, drawing a lot from my experience with this mill and it's CNC conversion over the last few years.

I will try to update and add to this list if I can think of anything more at a later date, it's going to be a few months probably before I can tackle this.

*General mechanics:*
-Entire machine needs to be stripped down and cleaned.
-All slideways need to be scraped back in, currently they're noticeably tighter at the end of travel. Might need to shim with turcite or similar.
-Gibs might need to be remade/shimmed
-Leadscrews will be replaced with ballscrews
-Covers need to be made to protect the Z and Y slideways, currently they're completely open except the front of Y where I have rubber sheet.
-DRO will be removed, I don't need it with ballscrews and I can use it on my smaller drill press/mill.
-Z motor mount needs to be remade sturdier and with a sheet metal cover for the belt. Might also go down to 5:1 ratio from 6:1.
-Considering adding either a counterweight system or a pneumatic piston to offload the heavy knee and make the Z motors life easier.
-I want to remove all parts not relevant to the mill anymore, like powerfeed axles that are not hooked up anymore etc.
-Replace the belts between motor and mill.
-Renovate/clean the motor.
-Implement a new oiling system(one-shot or similar)
-Replace the oil drain cap with a  valve for easier servicing.
-Fabricate covers for the gaping holes left by removed items.

*Control panel:*
-The control panel will be remade much more compact and I will try to "hide" all the electronics behind the mill, out of the way.
  This lets me run wires in better routes where they're less likely to become a space where chips start piling up
  The panel will be mounted on a swingarm from the base of the mill, similar to how it is on Maho 300C mills, should make it slimmer and less in      the way.
-Control panel needs integrated mounts for the hand tools I use for the mill, wrenches and such so I know where they are.
-Also needs a mount and powersocket for the impactwrench I use for the drawbar, if impossible add it as a powered drawbar.
I'm hesitant about a fixed powered drawbar as it will most likely be bulky and get in the way when/if I tilt the head.
-It would be amazing with some space for tool holders and endmills in here.
-The panel needs to incorporate at least a 19" monitor and a small work surface for the keyboard and pendant to lay.

*Cooling:*
-Cooling needs to be divided into three groups, air, air with mist and flood.
  Air for chip clearing with carbide tools
  Air with mist for chip clearing and lubrication with HSS tools
  Flood when using slitting saws where heat and lubrication becomes a bigger problem.
-I need bigger splash guards along the foot of the mill, a lot of the coolant splashes around and the floor tends to be soaking wet.
  The more I can catch and reuse the better.
-I need to make or buy a new proper coolant tank and I also need to get a pump that's really reliable unlike my previous attempts.
  I'm considering making a custom box and having it on wheels underneath the foot of the mill, this way it's easy to get all the fluid to run back      down into it and I can just roll it out to the side if I need to refill/service it.

*Vertical head:*
-Some kind of lights are needed on the head, it needs to be a very compact unit that won't get in the way.
-The coolant needs to be delivered from at least 2 directions, preferably with long and thin tips so I can get real close to the work.
  This needs to have plenty of adjustment both in height and width to accomodate different length of tools, I'm thinking a larger dimension of loc-line so it's plenty stiff.
-Preferably the head needs to have a machine mounted holder/crane, for taking it on and off with less hassle as it's currently a 45 minute procedure.
-One slightly more exotic idea is to rebuild the head mount to gain more space in Z, or build a second head bridgeport style with seperate motor. It's quite often I find the lack of Z height annoying but this alone would be a massive task and maybe better left for the future.
-A bonus would be having a weaker seperate high-speed head for small endmills since the big one maxes out at 1400rpm, this could easily be sourced on aliexpress/ebay for most of the parts I'd need and then just mount it to the two top bars for horizontal milling.

*General control:*
-Homing sensors need to be placed in a way that they're both protected and maximize travel lengths.
  Currently losing around 60mm in X, 15mm in Y and around 30mm in Z due to stupid placement.
-RPM encoder needs to be incorporated into the spindle, I think I can mount this on the rear of the mill, hooked up to the horizontal spindle.
-Coolant systems need to be hooked up to the CNC for automatic on and off.
-Handpendant needs to be included for easier jogging.


Generally I have massive problems with concentration and getting it all right the first time so I will try to draw up as much as possible in CAD so I don't start shooting from the hip when it comes to control panel placement, coolant lines, lights etc etc.


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## Janderso (Jul 19, 2021)

MrCrankyface said:


> Enter ... Stepper motors and CNC controllers.
> I'm going to use the Mach3 software which needs a dedicated PC for it.
> The power supplies and stepper drivers were bought but the rest have just been lying around for years.
> View attachment 306537
> ...


Amazing work. Nice save on the gear!
What, are you like Einstein or something?


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## MrCrankyface (Jul 19, 2021)

Janderso said:


> Amazing work. Nice save on the gear!
> What, are you like Einstein or something?


No I just learn from a massive amount of mistakes and then only show what went right.


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## MrCrankyface (Jul 1, 2022)

Came across some really cheap, used, aluminium sheet.
Without much thought I started chopping it up and practicing TIG-welding.
The idea was to make a coolant tank that could fit beneath the foot of the mill.
Somewhere in the process I completely forgot my goals and made it too big so it doesn't fit, and I don't feel inclined to chopping it up again. 
Either way pretty simple construction, complicated by the beat-up sheet.
4 sides folded up, with 2 extra ledges for mounting the top to, and works as reinforcement.



Cheap mains-power pumping unit, added some extra shape to this part because I had no piece big enough to span the entire width and figured I might as well experiment a bit.
The idea is that this part will just "sit there" and be easily removeable.



Second plate covers the rest and gets nutrivets and bolts to stay on.



Continuing with the "let's just get stuff done" mentality, I welded together a frame underneath to support the tub and tacked on some wheels.
Makes it easier to roll it out of the way after filling/checking/whatever.



So "kinda done". It's too big compared to what I initially aimed for and because the pump inlet needs a clearance beneath it, I suspect I will need a ridicilous amount of fluid in it to keep the pump happy.
I'm not satisfied with it but I also dont' want to cut it apart. 
So lesson learnt, make a plan and follow it, don't stray.
BUT I got a ton of TIG time, really managed to improve my skills and nail down some weird bugs in my welder.
It will definitely get used as a coolant tank for the mill in some shape or form, we'll see in some months I hope.
This is a bit of a practice spot, hence why there's so many different beads around it.


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## MrCrankyface (Monday at 4:29 AM)

Temporarily back on this project.
Chopped the tank up and re-bent all the edges, now fits somewhat neatly under the mill.
Tried annealing it this time by marking the aluminium with permanent marker pens before heating until it disappears, worked quite well!
To control this I have a 24V contactor for on/off of the pump which then goes to two valves.
Valve1 is electrically controlled so I can adjust the flow with a switch on the control panel.
Valve2 is a "regular" valve that recirculates back into the tank.
Not only does this make sure to mix the coolant but also makes sure I always have flow going by the pump, even when valve1 is throttled way down.




Since this mill has been quite low on the priority list there's been a lot of "emergency solutions" the last years.
Like when the Z-belt broke last time and I changed the gearing, which makes the control panel not fit anymore. and hence has been hanging on the side for a long time...



I got a bit inspired from seeing how some MAHO machines have their control panel and started replicating it.
I think this will be superior compared to the original setup for several reasons:
1. Monitor and DRO will not be affected as much by the machines vibrations and coolant spatter(monitor is already damaged from it)
2. I can move things around wether I want to work from the front or the side
3. When not in use everything can be moved out of the way.
4. Standing in front of the panel should keep you well protected from flying chips etc.




Since this lead to a full re-wiring I decided to overhaul everything whilst I was at it.
Changed out the old plastic hoses to these rubberized ones, way more flexible, spacious and looks neater.



All home-switches have been replaced with proper sealed ones, and adjusted so I can get maximum travel, this nets me another 2" of travel in X and 1" in Y in combination with having moved the magnetic scale to the front as well.




Control panel is still a work in progress but now incorporates switches for:
Main breaker(turns everything off in emergency)
PC on/off
CNC PSU's on/off
VFD on/off
Lights on/off
Coolant on/off/auto(controlled from mach3)
Stop and start for Mach3 programs
on/off/on switch for adjusting amount of coolant fluid
on/off/on switch for adjusting air regulator pressure
Also finally added a "proper" pendant but haven't configured it yet.
Once I can confirm that all functions work properly I will clean up the wiring mess and close this up.


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