Just bought a Viceroy TDS6 short bed

[CHJ]

I HP is more than enough to bite you if you don't give it due respect.

 

[minilathe22]

Go for the VFD, it is well worth it. Some advantages of the VFD other than just the variable speed:

Emergency stop button locks the motor shaft (like most cordless drills do nowadays)

Spinup time can be set (eg 5 seconds from zero to the full speed)

ability to run the motor at higher than 50Hz. Most motors can take at least 10 - 20% over their recommended RPM

ability to run the motor in both directions (be careful as faceplates/chucks will need a locking screw)

motor fault/overcurrent protection built into the VFD

probably others that I am not aware of myself.

 

[CHJ]

.......Emergency stop button locks the motor shaft (like most cordless drills do nowadays)
......

A little caveat on that dependant upon invertor and whether it has current absorbing and associated heat dissipation resistors attached, otherwise it just coasts to a friction stop (The motor energy has to go somewhere) also another need for locking chuck to spindle to stop inertia unscrewing it on most lathes.

 

[Farmer Giles]

Thanks Guys

I've fitted VFDs to a Colchester Chipmaster lathe and a Tom Senior M1 mill, the lathe was a Mitsubishi, the Tom Senior was an Allen-Bradley. I sold the Chippie with the VFD but I still have the mill. The mill currently has a 1hp 3 phase motor on it and it could really do with 1.5hp.

So I think the solution is to move the motor and VFD from the mill to the Viceroy and get a bigger motor/VFD for the mill later. Also the motor is an old Brooke Gryphon so shorter than modern motors so will fit in the cabinet.

Sometimes it takes a while for a plan to come together!

Cheers
Andy

 

[Farmer Giles]

The motor saga has nearly ended. I believe I have found out why the Tom Senior mill was struggling, for some reason I have used a 1hp VFD with a 1hp motor, you should look at the current required not the hp, usually I use the 2 x rule of thumb, I did with the Chipmaster and it went like a bomb. I can't remember why I did it, I suspect I bought the VFD for another project then didn't do it and it sat on the shelf so go re-used. I'll check the full load amps to confirm this but it is highly likely to be the issue.

So I have bought and older Brooke Crompton 3ph 1425rpm 750w (1hp) motor second hand for the Viceroy with physical dimensions that fit the lathe cabinet with room to spare, with a bit of luck the shaft size will be the same as existing too. It is dual voltage so I don't have to delve into the windings to break out the star point to make it delta as I have done before with old motors.

Once the motor is delivered I will look at the FL current at 240 3ph out and then decide on a VFD size. The VFD on the Tom Senior mill will probably be relegated to the meddings pillar drill I'm renovating which is 1/2hp so fits the rule of thumb but will check the FLA on it first, I'm working away from home at the moment so will do it when I get back.

EDIT - the 2 x motor hp rule of thumb is only a guide, you need to check the full load amps of the motor at the supply voltage to the motor and the VFD output amps to get it accurate. Places like inverter supermarket are good at sizing so a 1hp VFD is more likely to suit a 1hp motor but if you buy one off the bay then make sure they are not being optimistic. Either way check the FLA
Cheers
Andy+

 

[Farmer Giles]

The motor arrived yesterday, I didn't get much chance to look at it other than unwrap it to make sure there was no physical damage in transit. Physical size wise it looks perfect, from an full load amps perspective, it has one of those awful dot matrix punched ID plates and I believe it says 3.6 amps however I will double check this with the motor type data etc. The bearings sounded OK, it's previous life was driving a Boxford 280T metal lathe which has a cream ilivery, hence the motor colour.

If the 3.6 amps holds up, I may go for a WEG cold plate inverter, this has no cooling fan and relies on being bolted to a nice flat heat conductive surface. I would use an aluminium plate, possibly with a heat sink but I'm in Yorkshire where it is always a bit chilly, with a reasonable sized plate I think the 50W full load heat output will dissipate nicely. There is a model that has a rated continuous 4.0 amps output with 6.0 max, i.e. for 1 minute in every 10 minutes. Thinking about it, I do have a spare heatsink from a solid state relay so I may put that on the plate as belt and braces.

Why cold plate? Well, less noise so I can hear the radio rather than a cooling fan, plus less likely to draw dust from turning and other woodworking activities into it's innards. Also smaller so there is a chance I could mount it in the cupboard under the lathe, there is space above the motor and I don't think the combination of both will exceed 50c, plus I can bolt the aluminium plate to the steel wall of the lathe for additional cooling. Once the VFD set up, I shall not be fiddling with it, and if I ever do I shall make the plate easily removable so I can fiddle with it comfortably without the motor belt and pulley getting in the way. Alternatively I will mount it on the wall behind the lathe, I shall get it first then think about it.

Cheers
Andy

 

[minilathe22]

Yes I would think a fan cooled heatsink is asking for trouble. I am now wondering if my 1.1kW rated VFD has a high enough current rating for the 3/4HP motor I have. More low end torque would be nice. I found space to mount mine to the inside of the lathe casting.

 

[Farmer Giles]

I think you will, a 550W motor and a 1.1kW VFD should have enough current however you will lose torque at lower speeds irrespective of current, see previous post with examples for a 2hp motor. Now if you have belt/pulleys and a VFD you have best of both worlds, just select a low gear when you really need low end torque

 

[Farmer Giles]

The VFD and other bits purchased, so time to take the old motor out, and at the same time give it a bit of a make-over. The winch is on a beam trolley on the other side of the workshop so used the engine hoist to lift the lathe away from the cast base and motor.

You can see how tight it is in there for the motor, the VFD is going in there too, very soon

The new 3 phase and the old single phase on the bench, similar physical size but the white one is 1hp and the rusty old one is 1/4hp.

Happy days, the shaft diameter is the same, and similar lengths.

While it is on the bench I'll clean the base up, paint it, get the motor and VFD working together, then reassemble it with the new motor in place. I have a reasonable match for the original hammered paint in Rustoleum Combicolour, Hammertone Light Blue. I have a small tin plus a couple of aerosols. I found it difficult to get a decent consistent hammered finish by brush without sags or conversely brushing it out too much leaving it flat.

So I am putting the base coat on by hand to get some coating thickness, flatting it a little when dry and finishing it off with the aerosol. I would have got the sprayer out but it isn't a large surface area and by the time I had bought the thinners it was cheaper to buy the aerosol. I have no real desire to master the art of applying Hammerite beyond this lathe

Cheers
Andy

 

[Farmer Giles]

I started painting the door first, it, can be laid flat to paint and easy to get the DA on it if I make a mess. It doesn't look too bad but closer up there is a fair amount of rust and scratching.

So gave it a wash then sanded it down to remove all loose paint and gave it a rub down with degreaser.

The a light fill with Upol Dolphin Glaze. Normally I would fill and sand at least a couple of times but this isn't too bad so should get away with one.

Rub it down, I didn't bother going any finer than 120 grit on the Abranet.

I hand painted it very quickly so to avoid brush strokes, after a couple of days, here it is on the machine with very visible lines, you can't cross hatch like you can with enamel otherwise you get no hammered effect and given it is a Xylene based thinners I didn't want to add a paint conditioner. So this will be lightly flatted then sprayed to see if it gives better results.

If is warm enough tomorrow I shall give it go

Cheers
Andy

 

[Farmer Giles]

**WARNING - this is the most dangerous thing I have done to date, anybody of a sensitive nature may not want to go any further, don't try this at home unless you don't mind singing castrato**

Well, the base of the lathe was filthy, and my parts washer is hidden behind the blast cabinet which is hidden behind an IBC cage of firewood so I couldn't be bothered to drag it out. But the base needed a good clean before painting. The wife said she was taking the youngest to the market so I had a couple of hours at least :twisted:

So I threw the base in the sink in the utility room, she will never know, you won't tell her, will you? Please don't!

And drying on the draining board next to some kind of root vegetable, she grows loads of weird stuff so I have stopped guessing as I am invariably wrong.

And now painted up in Colchester lathe Dove Grey, I was going to use Bridgeport milling machine grey as I has some left over from painting the Manchester hacksaw but couldn't find it.

Next job was repainting the door with the aerosol, I flatted it with 240 grit, a bit of panel wipe and it came out much better with a nice even hammered effect.

I then starting concentrating on the main body of the lathe. I unbolted the left hand cast table and laid the lathe down and started giving it a sand ready for filler. The base was dented a little so straightened that up. I've placed the VFD on a 8mm Aluminium plate to start sizing up where it will go and whether it will fit. The inverter will go on the inside roughly where it is shown on the outside in the photo below. The aluminium plate is 8mm thick so I can tap it for the VFD, heat sink, fixings to the cabinet and the p-clips for cable strain relief.

The heatsink will be attached next to the VFD on the plate, as the plate is bolted to the lathe it will also be able to transfer heat to the cabinet. It will have a bit of heat conductive paste on the back of the VFD and the heatsink, and I will put a bit between plate and cabinet if there is any left in the tube. On full 4 amp load the VFD dumps 50W so it should be fine without a fan. The motor consumes 3.1 amps in delta configuration at max load so the VFD should run it fine given it can exceed the 4A for short bursts too. We will soon find out

Cheers
Andy

 

[minilathe22]

Impressive paint skills, that door looks brand new! I just went over mine with a brush...

 

[graduate_owner]

Farmer Giles - a couple of points about inverters. I bought one and the instructions specified mounting in a IP 55 ( or so) cabinet, to prevent ingress of dust and moisture. My previous inverter failed and I suspect because of dust etc. So I mounted my new one in an airtight oversized metal cabinet, to allow plenty of air moment around the unit, and hopefully allow warmed air to conduct to the outside. I also wired via a 50 degree thermal cutout, which hasn't operated yet. The lathe is operated using a remote switch and rheostat housed in a plastic box which has magnets glued to the base, so I can attach it to any convenient metallic part of the lathe, or milling machine, or surface grinder - the inverter is used for all three by plugging in the appropriate lead.
My second point is in regards to the use of low speed. The motor is cooled via a fan, which obviously slows down as the motor is slowed down, thus reducing the cooling draught. You could therefore cause the motor to overheat which is not only more expense, but more hassle in re fitting a motor in the lathe cabinet ( done that myself, I know how much hassle it is). One solution would be to fit a small single phase motor with a fan running at full speed to keep the cooling going, but there is not much space for this in the viceroy. Just be aware of this issue though, perhaps keep very low speed usage to a minimum, and arrange the pulleys so as to help with this.

K

 

[Farmer Giles]

Impressive paint skills, that door looks brand new! I just went over mine with a brush...

Thankyou, I never intended to give it the full monty, but it always happens, I start giving a machine a bit of TLC and before you know it its in bits. It will be impressive if I can replicate that finish on a vertical surface, it is easy when it's flat on the bench

Farmer Giles - a couple of points about inverters. I bought one and the instructions specified mounting in a IP 55 ( or so) cabinet, to prevent ingress of dust and moisture. My previous inverter failed and I suspect because of dust etc. So I mounted my new one in an airtight oversized metal cabinet, to allow plenty of air moment around the unit, and hopefully allow warmed air to conduct to the outside. I also wired via a 50 degree thermal cutout, which hasn't operated yet. The lathe is operated using a remote switch and rheostat housed in a plastic box which has magnets glued to the base, so I can attach it to any convenient metallic part of the lathe, or milling machine, or surface grinder - the inverter is used for all three by plugging in the appropriate lead.

Thanks G-O. The inverter I'm using has two thermal sensors, it will cut out if the ambient temperature reaches 50c or the heatsink reaches 103c. With regards to the dust, all the switch gear and the inverter will be in the cabinet, and with the door shut there is not much room for dust ingress. I don't think I will be giving it as much hammer as your good self, plus the inverter has no fan so attracts less dust. So I'm nearly using a similar method, not completely sealed as yours is, I'll see how it goes when I start making shavings, the motor fan is bound to drag some dust in.

My second point is in regards to the use of low speed. The motor is cooled via a fan, which obviously slows down as the motor is slowed down, thus reducing the cooling draught. You could therefore cause the motor to overheat which is not only more expense, but more hassle in re fitting a motor in the lathe cabinet ( done that myself, I know how much hassle it is). One solution would be to fit a small single phase motor with a fan running at full speed to keep the cooling going, but there is not much space for this in the viceroy. Just be aware of this issue though, perhaps keep very low speed usage to a minimum, and arrange the pulleys so as to help with this.
K

Thanks G-O, you also get much less torque at low motor speeds so using the gears rather than just the inverter to slow it down is a very good idea for two reasons. When I put the inverter on the Colchester Chipmaster, I replaced the variator (a very ingenious variable drive based on cones in oil) with the motor and VFD so effectively I had no other gears, but I only used really slow speeds for jogging the chuck around. On the Tom Senior M1 mill I have both belts and VFD, you can soon tell if your using too slow a motor speed as the torque drops off reminding you to use the belts, it comes second nature after a while.

I believe there are also some settings in the VFD so you cannot go past set low/high frequency hence motor speed thresholds. I'll check them out during commissioning.

I managed to do a bit more while the neighbours frightened the animals with fireworks. Plate drilled to M5 tapping size then holes transferred to the case and drilled 6mm. I'll tap the plate tomorrow and put it on the inside of the cabinet after mounting the VFD on the plate for a trial fitting.

Yes it does say "back bottom" on the plate, no sniggering in class please

I also got much of the cabinet filled and partially rubbed down, then ran out of 120 grit Abranet, I found enough later to probably finish it.

Cheers
Andy

 

[graduate_owner]

You certainly are making a good job of refurbishing that lathe. Mine - I had enough after changing the motor and repairing the tailstock, so it sits in my workshop resplendent with all original scratches, paint splashes and rust patches, but I enjoy using it.

K

 

[Farmer Giles]

Thanks G-O, it's a good point, why do I refurb it when it will probably not perform much different if I just fixed the main mechanical bits and start turning? I guess it is because it is a hobby and I enjoy using nice tools, but it may be genetic, my dad was the same One of the plus sides is you get to know the machine inside out which helps a bit when using it.

The main reason I am concentrating on this rather than my Roubo bench is paint, it will be too cold to paint soon so want to get this painted and put back together pronto.

I filled and sanded the body at the weekend, and the underside of the table was flaky rust so gave it a rub down and it will get a couple of coats of Alfa red. I only had a couple of hours as I had building work to do.

The various knobs and levers I had ordered arrived. The large knobs are for the missing meddings quill handles, I have one, with two missing. The smaller ones come in two flavours, 4 imperial for the meddings various levers, and I bought 7 metric ones for the various T handles on the tailstock and rest bases/banjos. I always buy at least one spare knob (said the actress to the bishop ) The levers are to lock off the tailstock quill and tighten the rests.

This evening I sat in the warm kitchen cleaning, sanding, degreasing then filling the tailstock, left hand table and the two banjos while quaffing a pint of home brew stout while the dog wandered the house whining trying to find somewhere to bury it's bone. Far better than watching the box

Tinkering time over until Friday.

Cheers
Andy

 

[Farmer Giles]

Busy day, I was working from home and there is lots going on at work, then I had a tonne of wood pellets delivered for the log/pellet boiler I've just had fitted and will be commissioned next week. Then the builder turned up, then the roofer so I had to work a bit later to complete the bits I had to get done.

So it was nearly 8pm by the time I got into the house, and the wife went out to a charity karaoke party with her theremin leaving me with the youngest, the eldest is at camp this weekend.

I wanted to get some of the lathe done as the heat sinks and some other bits had arrived. So I quickly drilled and countersunk the plate for some M3 bolts as the heat sinks were pre-tapped.

The youngest made a brew then we set about mounting the heatsinks and VFD on the plate with some hex head bolts and thermal grease.

Eight year olds never do anything without explanations so we discussed what the VFD did and why while we bolted it together. So I went through single and three phase theory which struck a chord as she recognised the similarity with sound waves her music teacher has been talking about, she plays trombone. She picked it up surprisingly quickly and went to bed with a book to learn more about volts, amps, AC and DC etc.

Once she was abed, I set about the tailstock with some Abranet to sand down the filler from last week and opened a bottle of homebrew. Tinkering time over today.

Cheers
Andy

 

[Phil Pascoe]

A karaoke party with a theremin?????? Bleddy hell, that must be an education ....... :lol:

 

[Farmer Giles]

A karaoke party with a theremin?????? Bleddy hell, that must be an education ....... :lol:

She plays the saw as well, but I don't think she has taken that with her this time

 

[Phil Pascoe]

Bill Bailey plays a theremin amonst other things - if you ever get the chance to see him he is brilliant. My wife hurt for two days from laughing - and she wasn't bothered about seeing him.