Denford Software & Machines

So after a real busy last few years setting up my own business, my tds is the main part of it.
I'm planning to turn my Viceroy TDS 1/1GB metric. into CNC as i need to cut both inch and mm threads, now i did plan to go the change gears rout, got the quadrant cut out to do it a few years back. in.09. just a few weeks before the company i was working for went bust... but now looking at the hole thing,and price.....i'm thinking cnc over gears, plus i think their will be a limit of threads i could cut with the gears and then the carry on of reversing the lathe all the time after each pass would be a pain, plus i will always get some erro in the thread and the amount of time per thread will be alot longer than on cnc.. so i remember dazz saying he was going to do it , unsure how far he's got to date??
now whats turned mr into a cnc fan is after watching this vid
https://www.youtube.com/watch?v=Rt2ceHE ... ture=inbox

i've been talking to the fella and he's given me some good advice on what to get..

so i'm planning on running
mach3
The G540 4-Axis Digital Step Drive from Gecko as it should not take up much space so a smaller housing
plus a 425oz nema 23 motor geared 2.1 down for the
x axis.. but i think i might just go nema 34
and a 906oz nema34 motor geared down to 3.1 for the z axis
and 1 x The SF1605x1100 machined ball screw for z axis
and 1 x SF1610 C7 Precision Ballscrew Spindle for the x axis

now what i'm a little stuck with, is to make it fully cnc only or just to mod the ball screws so i can fit handels . i do think i would be better that way as i don't want the motors sticking that far out ?
has anyone else done this yet?

Hi there, why do you need a 4 axis drive unit, you only have 2 axis to drive, you can get single axis drives from many sources in the uk.
I would go for a smaller pitch on the x axis, 5mm max.
If you're going to use rolled screws go for C5 this way you'll get zero backlash with one nut. (bxr ballscrews).
Forget handles, you'll soon get past the need to have your "hands on" and you'll have the keyboard to use or a pendant (contour shuttle) for the rare time you want manual operation.
I've converted a Harrison M300 lathe to cnc, and have plans to convert the boxford AUD lathe soon.

angel-tech wrote:Hi there, why do you need a 4 axis drive unit, you only have 2 axis to drive, you can get single axis drives from many sources in the uk.
I would go for a smaller pitch on the x axis, 5mm max.
If you're going to use rolled screws go for C5 this way you'll get zero backlash with one nut. (bxr ballscrews).
Forget handles, you'll soon get past the need to have your "hands on" and you'll have the keyboard to use or a pendant (contour shuttle) for the rare time you want manual operation.
I've converted a Harrison M300 lathe to cnc, and have plans to convert the boxford AUD lathe soon.

Hi mate thanks for your info. this is what i'm wanting from members, because i'm just new to cnc
and as you'v pointed out 4 axis, where is i over looked that..
I'm picking things up real slow. have you any links to the items you'd have me using for my lathe? i'm not rushing into this i'm planning 3 to 6 month before i jump in, as i'd rather read up/ post what i want to no and only buy once!

plus if admin don't mind could you post photos of how you've done your m300?

do you think the motors i've picked out are ok for my lathe?

the main problem with most lathe conversions is getting the x axis ballnut under the cross slide. I've mounted the ballnut to the rear of the apron and the bearing, ballscrew, motor, and pulleys to the end of the cross slide.
The z axis is mounted under the ballscrew from the rear of the bed, this way you can use a shorter ballscrew and not have it sitting under the chuck.

angel-tech wrote:the main problem with most lathe conversions is getting the x axis ballnut under the cross slide. I've mounted the ballnut to the rear of the apron and the bearing, ballscrew, motor, and pulleys to the end of the cross slide.
The z axis is mounted under the ballscrew from the rear of the bed, this way you can use a shorter ballscrew and not have it sitting under the chuck.

YEA i'm just thinking on how to get the x xais on, i'v found a Square Nut Model, but we'l see how that go's, as i'v only got 25mm..max

could you put some photos up of yours as i'm finding it hard to take in how you've got z axis .. or inbox them to me?


i'm sure admin wont mind you posting on here as its to help, us denford lot out!
cheers

pm me your email address and i'll send you some pics

plus if admin don't mind could you post photos of how you've done your m300?

post away!

I don't think I've seen a Viceroy converted to CNC before...Dazz seems to make all kinds of great stuff with his manual m/c.

Hi

Progress on my CNC conversion is pitifully slow. I am too busy making stuff the old fashioned way.

The first step is to get electronic control of the speed. This is not essential but very useful. I am most of the way through changing the 4-step pulley to a single poly-Vee pulley with VSD. I have a 1.5kW motor to retain high torque at low speeds. VSD provides constant torque regardless of speed, and allows the motor to be driven at up to 150% rated speed. With VSD, a single pulley will go from near zero to 1500rpm.

I plan on using LinuxCNC. It is free and I like Linux. There is an active development team who will answer questions. Nothing wrong with Mach3.

Most CNC conversions fit a sensor that ticks once per spindle revolution. If you want good threads, this is not good enough. It doesn't provide enough information to keep the spindle in sync with the tool. I plan to count gear teeth with one sensor, and another sensor counting a one tooth gear. (most cars use a single sensor that locates TDC with a missing gear tooth) The combination will give accurate spindle speed and position.

I plan on using DC servo motors but that is only because I know something about control systems engineering and PID loops. Nothing wrong with good steppers.


The X axis ball screw arrangment will be tricky. a 16mm x 5mm screw will fit under the cross slide but the support bearings won't. I am thinking of putting the motor at the rear of the lathe rather than sticking out the front.

Not sure that I will replace the lead screw with a balls screw, but either way, mounting the support bearings will be an issue. If the lead screw is replaced, then it would make sense to replace the entire apron.
The apron would then only hold the ball screw.

Just my thoughts.

Good luck wth your conversion. Post lots of progress photos. I suggest posting them in the Projects forum.

Post photos on here mate, if you struggle with size just upload to photobucket, then copy the links, or email them to me on graham.jakeman (A)yahoo.co.uk and i'l put them up.
well i'm planning to get
this https://www.ebay.co.uk/itm/3Nm-68V-CNC-S ... 4ab602b6b6
or
https://www.ebay.co.uk/itm/3Nm-CNC-Stepp ... 33742af65d

Daz have a look on this site https://www.mycncuk.com/forums/lathe-bui ... rsion.html
or you could get a balnut like this https://tech.thk.com/en/products/thk_ca ... php?id=884

I'm to now playing with linux cnc, i did not even no about it, but i'm running linux mint on both pc only downloaded the free cad stuff on that, then i come a cross emc2 and it seams easy to use!

so far i'm thinking of stripping the apron off and making a new one then adding ballscrew/nut to that.....or making one at the rear of the lathe so its all at the back ,,,unsure..but i've a lot of time

here's a myford ML&/S7 converted to cnc https://www.jeffree.co.uk/pages/ml7-cnc/ ... r-Ar-11234

I like the way he's mounted the motors so they are not sticking out ,
I hope you don't mind me posting links to other sites admin>?

Hi

Some interesting CNC retro fits.

For a CNC Viceroy, if the apron is discarded, it would be worth looking at replacing the carriage and cross slide. There would be no requirement for a top slide either. This would allow a taller and thicker carriage giving more space to mount the ball screw. It may be easier to make a new carriage/cross slide than to modify the existing one.

I already have a Myford looking T-slotted cross slide made by the previous owner. This could be used as a poor man's tool changer by fitting different tools along the cross slide.

The cheapest CNC lathe is to buy a faulty one with good mechanics. It would then be relatively easy to fix the electronics and use Mach3/LinuxCNC for control. I haven't found one like this in my part of the world. Good used lathes are very rare here.

Dazz

dazz wrote:Hi

Some interesting CNC retro fits.

For a CNC Viceroy, if the apron is discarded, it would be worth looking at replacing the carriage and cross slide. There would be no requirement for a top slide either. This would allow a taller and thicker carriage giving more space to mount the ball screw. It may be easier to make a new carriage/cross slide than to modify the existing one.

I already have a Myford looking T-slotted cross slide made by the previous owner. This could be used as a poor man's tool changer by fitting different tools along the cross slide.

The cheapest CNC lathe is to buy a faulty one with good mechanics. It would then be relatively easy to fix the electronics and use Mach3/LinuxCNC for control. I haven't found one like this in my part of the world. Good used lathes are very rare here.

Dazz

Hi
I'm just thinking of getting some steel and making an apron out of that. never even thought about making a hole new saddle, but it might be worth doing in time,
I have a book/plans to make this metal casting set up https://www.artfulbodgermetalcasting.com/
so if i'm any good with castiron i could make one, i've done casting in ally so don't see why not..
but i'm like you, other things get in the way...

well the topslide is coming off thats 100% going, what i was thinking is getting a T-slotted cross slide,like yours.. but say a row of 4-6 t slots made with a lot more space under to fit a ballnut as you say, if you look at https://www.latheparts.co.uk/ he makes all sorts of stuff, back in 08 i think i got a price for a boring table for my TDS and if i remember right it was only going to be £110 plus shipping! so i could sharp kncok up a drawing for him to copy where i could have room to put my ballnut!


I did think about getting an old Denford orac lathe , theirs one on the bay for £650. just needs finished off as its only 80% converted to mach3..

But the problem with that is the space i have..well don't have
and i could not sell my TDS

I'm struggling with the thought of selling the thread dile and travling steady to help fund the costs of the cnc , then when i do go cnc i will have a spare gear box top slide and other parts
which i'm unsure if i'd sell them!

could you not ship a lathe over from ozz ??

that's actually a Starturn not an Orac.

angel-tech wrote:that's actually a Starturn not an Orac.

aye mate so it is! its smaller than the orac ?

Hi

I have looked at home foundry work but for me it is not viable. The cost of the furnace, crucible, tools and safety equipment make it too expensive for a small number of jobs. If I ever get to do a CNC conversion, I would focus on making the pattern (the labour intensive part) for the carriage and get a professional foundry to do the pour. That is reasonably cheap to do and the chances of success are good.

Turning a casting into a finished CNC carriage wouldn't take that many machining operations.


I wouldn't sell the original apron/carriage. I can't think who would pay a decent price for those items. I would keep them just in case I or any future owner wanted an original manual lathe. Not everyone wants a CNC machine.

Dazz

dazz wrote:Hi

I have looked at home foundry work but for me it is not viable. The cost of the furnace, crucible, tools and safety equipment make it too expensive for a small number of jobs. If I ever get to do a CNC conversion, I would focus on making the pattern (the labour intensive part) for the carriage and get a professional foundry to do the pour. That is reasonably cheap to do and the chances of success are good.

Turning a casting into a finished CNC carriage wouldn't take that many machining operations.


I wouldn't sell the original apron/carriage. I can't think who would pay a decent price for those items. I would keep them just in case I or any future owner wanted an original manual lathe. Not everyone wants a CNC machine.

Dazz

yes that whould be a better way to do it, theirs a foundry not to far from me, so i could sharp pay a falla to cast one for me, tho i woul like to have a go myself one day, the cost of the furnace is real cheap if you build it yourself, think it works out about £60-80 but thats for the reflectory as the body is an old beer kegg, or gas bottle, problem is the long time to make a patten, when i tun to cnc it will be staying with me for life, would keep the saddle and apron, but gerabox and everything to go with it and topslide could go, as i don't think it would get used again by me!

going to have a look at a TDS lathe tonight for my mate as he wants one, showing him mine to day and got on about cnc and its seams he wants to go that way,
so if everything is sound with lathe, you might be saying 2 TDS lathes turned to cnc soon!

Hi

The post here viewtopic.php?f=34&t=3218
includes drawings of a ball screw saddle and ball lead screw. The cross slide drive arrangement is quite compact without excessive overhang. It wouldn't be too hard to copy this arrangement and retrofit to a Viceroy. I just wish I had the time to do it.

If the gearbox is removed, that would be the obvious place to fit the ball lead screw drive.

This would be an ideal project for those sad looking Viceroys for sale with half the parts missing.
The hard chromed bed means zero wear. As long as the bed isn't mauled, it should be OK for a CNC retrofit.

The problem I have is that Denford lathes are incredibly rare in this part of the planet. I am only aware of two other Viceroys and no Denford CNC lathes. Most small lathes here are ex-schools (worn, battered and lost/nil accessories), Myfords (versatile but too small) or Chinese junk (just not worth looking at in any condition). Very occasionally a good lathe comes up for auction and attracts fierce (high) bidding.

Importing used machinery from other countries has high risk and lots of cost. I got a quote for shipping a Viceroy/Easiturn from the UK to New Zealand. This shipping cost is the same as the value of my lathe. Over half of the cost is in getting a lathe to the port within the UK. Importing a lathe from the UK is not economic.

I have decided that my Viceroy is too good to tear down for a CNC conversion. In the unlikely event I find a suitable (old and tired) Viceroy, I would consider doing an Easiturn type conversion.

Dazz