Lathe suggestions?

[routercnc]

The lathe arrived this week - hurray!

It arrived in a big wrapped wooden box:


The drip tray was on top in bubble wrap:


Levering off the lid revealed the well packed machine with all the accessories:




The invertor is behind this cover. A branded model, with a branded contactor, so bodes well:




A look behind the end cover panel:


Sensor for the rpm readout (there is a once-per rev small metal rod sticking out of the shaft):

Should be quiet easy to add a multi-pulse index wheel for cnc threading (at some far distant time!)

Declared run-out not too bad (will check if this is accurate later):


Started stripping off some of the parts to make it lighter and give better access to fit the DROs:



Started on the cross-slide DRO. A bit worried that the one supplied for this machine is 100mm travel but the cross-slide travel is about 115mm. Admittedly it probably won't go right to the back of the machine but if in the future I forget it could damage the sensor. I'll ask Warco about it this week if I get a chance. May have to limit slide travel.

I can't see any way to make the standard brackets which come with the DRO fit. The slide has to be stepped back to give access to the saddle lock cap head (and clear the gib lock bolts), be low enough to miss the top slide, and the read head has to be positioned so that it can travel the whole range. This puts it in the middle of no-where. So, made some measurements and did some CAD. Printed it out as a trial fit:


Setting up some 6mm aluminium plate:


Done:


Light coat of Zinc spray, drilled and tapped the carriage (M4) and offered it up:


Starting to dial in the read head bracket. So far looks like it needs about 0.4mm shim on the left. Note that the main body is NOT attached to the slide yet, it's just loose on the reader. Once dialled in vertically I'll do the fore/aft dial in using the slots in my bracket.


This is in the same position as the Warco display model but I do need to be careful that the tailstock does not get slammed into the back of it during use. It will hit the 6mm bracket not the sensor itself but it is only secured with 2off M4 into soft cast iron so could do some damage. Maybe add a rubber bump stop on the tailstock front edge?

Thinking ahead I had a look at the longer DRO for the Z axis. Since this mounts on a non-machined surface it needs to be levelled. I was disappointed that the kit did not come with levelling blocks so I'll have to make my own.

Here is the Warco display example which uses grub screws top and bottom to dial it in:



Looking further ahead - I will obviously need to lift it onto the bench I also tried to feel the weight at the tailstock end and the chuck end and it is still very heavy. I had got a few friends lined up to help lift it but now I'm not so sure. Will probably hire an engine crane to be on the safe side.

[Neale]

I note from photo 3 that they are still printing "This Way Up" arrows on the wrong face of the box...

[Jonathan]

A friend of mine recently got a lathe (Colchester student, model up from mine) and bought some carbide-tipped tools for it from aliexpress. I was a little hesitant, but they seem pretty good and very cheap, so you may want to consider that. It's all to easy to spend as much as the lathe cost on tooling for it, given time...

[Doddy]

Looking further ahead - I will obviously need to lift it onto the bench I also tried to feel the weight at the tailstock end and the chuck end and it is still very heavy. I had got a few friends lined up to help lift it but now I'm not so sure. Will probably hire an engine crane to be on the safe side.

When faced with the similar problem (Myford ML7) I bought a couple of block-and-tackle pulleys from Amazon for ~£5 each and hung them from some 4x2 across the eaves of the shed. Not claiming it was the best* way, but it got me out of a pinch.


* Nor the worst - that'd be my lifting of an air conditioning unit 10ft off the deck using a ladder-against-the-wall, some rope, a load of buckets and a hose-pipe.

[routercnc]

Hi Jonathon,
Thanks for the info. I've actually got a set of carbide tools on back order. It was a set of 9? for ~£52 but they came 'free' as part of the Warco lathe bundle, along with bits I was going to buy anyway. I also bought a nice cut off tool for about £30.
Should get me started but I'll look into Aliexpress as well once I know what I really need for tooling.

Hi Doddy,
Sounds like an interesting way to do it! My garage is part of the house so wouldn't want to put load on the first floor joists. I had a look at crane hire and there is a hire place about 2 miles from me at £35 for one day for a 1 tonne engine crane. If this includes delivery (not clear on the website) I'll go for that.

[routercnc]

Well I had lots of problems trying to dial in the bracket using shims. Eventually realised that I'd counterbored the bolt holes quite deep leaving only a bit of material at the bottom of the hole and every time I tightened the bolts it was extruding aluminium out of the bottom surface - this varied the height each time!

Anyway, I started again and made up a new bracket. This time it had 4 grub screws to do the levelling and shallow counterbores with smaller holes. I wanted to get each side of bolts and grub screws in a line, but there was not enough space. So I had to offset them a bit. Before levelling I ran an end mill down the grub screw holes to clear the paint off the cross slide to make sure they were biting onto the metal, not the soft paint.

Didn't take too long to dial in left to right:




Instructions say within 0.1 mm - I managed to get 0.01mm so OK there. Then dialled it in front to back.

At this point I realised there was another problem. The slide I'd been supplied had a travel of 100 mm but the cross slide travel was 115 mm. Although I might not use all the travel, it bothered me that at some point in the future I might damage the read head. I phoned Warco and they did say this was the model they fitted to this lathe. I mentioned that I'd be happier with the 150 mm travel model, even if the scale stuck out the back ~30mm and they were OK to swap it (just £5 more). I should get that next week so I stopped that job.

The longer slide was next. I made some brackets with grub screw levellers in:




Clearing the paint with an end mill:






After ALOT of messing about, clamping, adjusting, shimming I managed to get the other end pretty close to level then drilled the tapped hole. Once this was bolted I set about dialling the scale in vertically (slots in scale ends) and fore/aft (grub screws):





I'm thinking about using a cable guide for the 2 cables. I don't like the idea of them being loose and getting caught in a bird's nest and pulled into the chuck, or sliding around on the drip tray.



Now for the drop link bracket:


Last part to make will be a space block between this drop bracket and the read head. I measured 6.86 mm gap so I'll machine something to suit. I think there is a tolerance fore/aft on the read head so as long as it sits somewhere in the middle of the channel on the scale it should be OK.


Then I'll tackle the cable guide shelf and start routing the cables off to the tail stock end and behind the splash guard up to the read out. This will mount somewhere up on the left side near the motor controls.

[routercnc]

Finally finished both DROs at last!

Z axis
Here is the spacer plate between the drop down bracket and the read head. This needs to be reasonably accurate in thickness to put the read head in about the right place on the scale:


Checking to see if it would work - also to see if the numbers went the right way (positive to the right). It wasn't obvious which way round the read head should go and there was no mention of anything in the instructions for the scales:



Bump-stop to bump-stop is a bit less than the quoted travel (450 mm) unless you angled the top slide round and included that as well(~70mm), otherwise all good.

I'll stop briefly here to point out that initially I was uncertain about fitting DROs given that it is likely to go CNC in the future. However I'm glad I did because the handwheel graduations on Z are not something logical like 10 lines of 0.1mm (giving 1mm per big number). No, they are 10 lines of 0.25mm, which means each big number is 2.5mm. I guess they are trying to get a metric-ish imperial system. The X axis cross-slide had a different number but was also not 0.1mm per line. Can safely ignore all that.

Back to the Z axis DRO. I added a 60mm x 60mm x 3mm aluminium angle bracket to run the energy chain in. This bolted to the holes used to fix an optional mill head attachment.





Note that I had to cut the energy chain open to lay the cables in as it was not the type with slots in. I couldn't feed the cable through as the connectors on the end were too big.

I think the angle bracket shelf will attract swarf etc. so thinking about a plastic curtain arrangement of some kind hanging off the top of the saddle. Not decided yet.

X axis
I wasn't happy with the original 100mm scale so swapped it for the 150mm model. This hangs out the back a bit so needed a bracket making:






Seemed to have made a Minion!



Here it is fitted:


The other end was just a simple round spacer tube.

Dialling it in:

In this shot you can also see I swapped out the cross slide locking bolt from a cap head to a hex head, otherwise I wouldn't be able to use it. May swap the gib bolts in the future too.

Last bit to do was fit the splash cover. After looking at lots of options I decided to go for a bracket off the back of the scale. Here roughing a pair out of a bit of box section:


Done:






I'll leave fitting the display readout until the lathe is set up on the bench - hope to do that this weekend.

[cropwell]

It is interesting to see how you have done this, as I have the Sino DRO as a factory fitted option to my Amadeal 290-VFF.


I notice that the bracket on the cross slide will limit the tailstock. On my machine the read head is fitted into the recess of the saddle. This means that the tailstock can get closer to the chuck (only about 10mm further away than without the DRO). I seem to do a lot of centre drilling of short pieces, and I prefer to do it with as little stick out of the quill as possible.


Here are a few pictures to show you what I mean.





You may note that the cap-head screw that stops the tailstock smashing the DRO scale is bent and needs replacing. Also the gib screws are not accessible with a hex key and the cross slide lock can't be used. If I need to adjust the gib or lock the cross slide the easy answer would be to replace these with hex head screws, then you could just pop a spanner on them.


I think the spacers that the factory fitted are a bit naff and would look better as a single piece. I may make something better if I ever dismantle the DRO fitting. The other thing I would do is tidy up the cable routing and use P clips rather than cable ties.

As a last note - the red things are plugs in the T slots to stop coolant pissing over the apron and onto the floor and/or me. They are only red 'cos that's the colour ink I had in the 3D printer.



Cheers,


Rob

[routercnc]

Hi Rob,

Cheers for that. Yes, I looked at different ways to mount the cross slide read head because I didn't want to lose tail-stock travel, plus was worried about it smashing into the DRO. I tried to fit it as yours is to get more travel but it wouldn't fit. I can't remember if it hit the gib lock screws, or it didn't allow enough cross-slide travel. Maybe I'll look again in the future now I have the extra 150mm version.

I also looked at adding a hard bump stop strip behind the DRO (to do the same job as your 'bent' screw) but it was all getting complicated. At the moment it will hit the plate that the read head sits on, which will probably put it out of alignment if it is hit hard enough.

Some lathes have the gib screws on the head stock side, which would make this installation much more compact/safe.

I'm thinking of leaving it for now, getting it set up and levelled, then having another go in the future once I've tried it all and looked at what tailstock travel I have / need . . . watch it be like this for years!