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Thanksgiving.
I'm sitting on the sofa still feeling stuffed I'm a brit but SWMBO / XYL is a California girl.
My main lathe is an early Myford ML7. I'm only the 4th owner as far as I can tell. I've replaced the old single phase motor with a 6 pole 3 phase motor and variable frequency drive (VFD). The single phase motors are rough and noisey due to torque ripple and don't like frequent starting and stopping. That is why the Super & had a clutch. Adding the VFD makes the lathe much quieter, gives better surface finish and doesn't mind stopping and starting. Next modification is an electronic lead screw (ELS). This is stepper drive for the carriage thet is syncronised to the spindle. It allows you to cut any pitch thread without a gearbox or manually ghanging gear wheels.
Probably of more use for electronics is my small vertical mill. It's lightweight so would not be great for hacking out lumps of steel. However it has a relatively high speed spindle and long X travel on the table. The high speed spindle is good for running small cutters foe light alloy or plastic. It makes tasks you normally hate like cutting a hole in a panel for a meter or display soo easy.
I don't want to go down the CNC route as A. I don't do enough and B. I don't use CAD.
Robert, thank you so much for your post. I was well aware of the difference in torque ripple between single and three phase motors and was wondering whether my heavily tweaked Hobbymat lathe (bought new) would benefit from a three-phase motor, so I bought it a three-phase motor. Annoyingly, my static three-phase converter (used for the Colchester Bantam) won't go as low as 250W. Whoops! Internet searches didn't come up with anything useful regarding VFD drive and ripple. Any other comments you might have regarding VFDs and motors would be very welcome.
I'm happy to swap change wheels (Hobbymat) or pull levers (Bantam) to cut threads, but I can see the attraction of an electronic leadscrew. I have recently learned that it is a stupid idea to think that you can cut internal threads in 306 grade stainless steel; horrible stuff.
I suspect I am fully with you on your A and B points.
Zenith wrote: ↑Thu Nov 27, 2025 4:08 pm
I hope you are having a nice time.
Is it a fairly relaxed day of eating and drinking too much, or is it a family thing where you are obliged to invite relatives you don't see very often? Then they kick off on politics, or their great interest in some sport nobody is interested in, or some family row everyone thought was forgotten, such as who collared granny's clock and shouldn't have. Then you remember why you don't see them very often.
It can be both. In our case it was indeed some individuals you don't see often but was a relaxed day. No politics nor sports or other stupid bullshit.
An old gray beard with an attitude. I don't bite.....sometimes
Robert wrote: ↑Thu Nov 27, 2025 9:29 pm
Thanksgiving.
I'm sitting on the sofa still feeling stuffed I'm a brit but SWMBO / XYL is a California girl.
My main lathe is an early Myford ML7. I'm only the 4th owner as far as I can tell. I've replaced the old single phase motor with a 6 pole 3 phase motor and variable frequency drive (VFD). The single phase motors are rough and noisey due to torque ripple and don't like frequent starting and stopping. That is why the Super & had a clutch. Adding the VFD makes the lathe much quieter, gives better surface finish and doesn't mind stopping and starting. Next modification is an electronic lead screw (ELS). This is stepper drive for the carriage thet is syncronised to the spindle. It allows you to cut any pitch thread without a gearbox or manually ghanging gear wheels.
Probably of more use for electronics is my small vertical mill. It's lightweight so would not be great for hacking out lumps of steel. However it has a relatively high speed spindle and long X travel on the table. The high speed spindle is good for running small cutters foe light alloy or plastic. It makes tasks you normally hate like cutting a hole in a panel for a meter or display soo easy.
I don't want to go down the CNC route as A. I don't do enough and B. I don't use CAD.
Robert.
Thread cutting and change wheels is sure an art but on my Harrison 12 I'm lucky to not need to venture into the gearchest as this lathe is fully optioned and with a Metric/Imperial changeover lever. There are a very few of the less common pitches I can't cut but with fingers crossed I'll never need them.
In the Harrison Lathe io group one of the dudes went to a lot of trouble to build a SW package to help with change wheel selection to enable use of the main gears you have and an assortment of change wheels.
Sorta mix and match to get the correct pitch or so darn close to it not to be an issue except for loooong nuts. https://ridethegeartrain.com/
I wound up excavating my South Bend 10K last night to shorten a piece of lamp coupling pipe.
Got it a few years ago from a friend who had a machine shop, and I'm running it on single phase 240 using a TECO VFD with soft start.
It doesn't get used often (obviously; it's half buried), but when I need it it's a really handy thing to have. One of these years I'll get my hands on a vertical mill...
And in the bottom photo a Lincoln MIG set. I've got a modern inverter MIG set, which also does MMA. I haven't used it for a time, but it paid for itself welding patches on the bottom of my Ford Mondeo, before it got beyond and had to be scrapped. The MMA function is OK, but I have a couple of MMA inverters, which are smaller and I'd rather use. I haven't used those for a time either.
Yup. Bought the Lincoln in the early 00s when the catalytic converter flange on my Miata's exhaust broke off. The flange was mild steel while the rest of the catback was SS, and in near perfect condition. I’d wanted to get an aftermarket exhaust, but as the OEM one was still in such good shape, I just couldn’t see scrapping it that soon and elected instead to drop the $600 on getting the welder to fix the old exhaust. Got a new toy and several more years out of the original exhaust - win-win.
nixiefreqq wrote: ↑Fri Nov 28, 2025 1:20 pm
Somehow I always expect you guys to show off your hybrid wafer and die wire bonding setups.
Instead we see engine lathes and welders.
Stone knives and bearskins.
Agreed, lathes and welders are low technology, but the great thing about them is that:
(A) They're affordable and very versatile
(B) You can use them to make high technology
I've made a lot of test gear in steel cake tins and tobacco tins. (If it can keep stuff fresh, it's good for keeping EMC out.) Didn't look much, but the laughter stopped and throughtful expressions appeared when people saw results better than (expensive) commercial equipment.
EC8010 wrote: ↑Fri Nov 28, 2025 1:49 pm
I've made a lot of test gear in steel cake tins and tobacco tins. (If it can keep stuff fresh, it's good for keeping EMC out.) Didn't look much, but the laughter stopped and throughtful expressions appeared when people saw results better than (expensive) commercial equipment.
nixiefreqq wrote: ↑Fri Nov 28, 2025 1:20 pm
somehow I always expect you guys to show off your hybrid wafer and die wire bonding setups.
instead we see engine lathes and welders.
stone knives and bearskins.
You need the space for a tool, to be able to afford it (not so bad these days with a lot of good used equipment around), and an amount of work to justify it. You also need the skill to use it, and that can take a lot of practice.
About 15 years back I was queuing for the ferry from France and in the next line was a 1931 open top Rover. It had a brass badge on the side saying "The Duchess". I asked the lady sitting in it if she was The Duchess. She looked coy and said that was just the name of the car. Her husband came back (The Duke?) and I asked about the car. Vintage car owners always like to talk about their cars. So he told me about it. Then I asked him about spares and mentioned piston rings. He said they were fairly easy. You got some cast iron pipe of a particular sort, and then he described how it was machined into piston rings. It turned out he had another half dozen similar vintage cars and a fully equipped machine shop. I gathered he had a small business on the side, producing impossible to get spares for other vintage car owners. He was about retirement age.
Half a dozen vintage cars worth thousands, the room to keep them garaged and a fully equipped machine shop. He can't have been short of a bob or two.
sorry....forgot that according to the pictures in magazines, high tech electronic fabrication these days is done only by gray haired grannies or tiny Asian girls peering into microscopes.
Zenith wrote: ↑Fri Nov 28, 2025 2:32 pm
You need the space for a tool, to be able to afford it (not so bad these days with a lot of good used equipment around), and an amount of work to justify it. You also need the skill to use it, and that can take a lot of practice.
Agreed with all of that, although buying a used machine tool is a lottery unless you can talk to the chap who has used it for the last ten years. Shortage of space is part of why Myfords have become so expensive; you can put a Myford (or smaller) in a converted loft or box room. Anything bigger needs a concrete floor and probably three-phase electricity. I first used a lathe at age of 14 at school; frightened the willies out of me. Forty years later, I was very nervous the first time I pulled the big red lever on my Colchester Bantam (3 HP motor). I'm still very cautious but my skill has improved significantly and I've enjoyed learning.
Sounds like your vintage car chap had found a way of making his hobby pay for itself.
But the key thing about a hobby, whether it be solder-slinging or swarf production is that it keeps the brain active. I looked around at work some years ago and wondered what many of them would do in retirement...
EC8010 wrote: ↑Thu Nov 27, 2025 10:26 pm
Robert, thank you so much for your post. I was well aware of the difference in torque ripple between single and three phase motors and was wondering whether my heavily tweaked Hobbymat lathe (bought new) would benefit from a three-phase motor, so I bought it a three-phase motor. Annoyingly, my static three-phase converter (used for the Colchester Bantam) won't go as low as 250W. Whoops! Internet searches didn't come up with anything useful regarding VFD drive and ripple. Any other comments you might have regarding VFDs and motors would be very welcome.
I'm happy to swap change wheels (Hobbymat) or pull levers (Bantam) to cut threads, but I can see the attraction of an electronic leadscrew. I have recently learned that it is a stupid idea to think that you can cut internal threads in 306 grade stainless steel; horrible stuff.
I suspect I am fully with you on your A and B points.
What size is your motor? I have a small VFD spare...
EC8010 wrote: ↑Thu Nov 27, 2025 10:26 pm
Robert, thank you so much for your post. I was well aware of the difference in torque ripple between single and three phase motors and was wondering whether my heavily tweaked Hobbymat lathe (bought new) would benefit from a three-phase motor, so I bought it a three-phase motor. Annoyingly, my static three-phase converter (used for the Colchester Bantam) won't go as low as 250W. Whoops! Internet searches didn't come up with anything useful regarding VFD drive and ripple. Any other comments you might have regarding VFDs and motors would be very welcome.
On this subject I have but one image to refer to:
That's what comes out of my sockets, if you wire them right, and pick the right cables in the fuse box.
402V. OK, 2% low from 415V, but nothing to worry about. I'll have a look in my incoming box, but I'll be amazed if all three phases are there. My understanding is that houses in the UK are wired sequentially with phases down the street; whereabouts are you to have three-phase?
EC8010 wrote: ↑Sat Nov 29, 2025 11:11 pm
402V. OK, 2% low from 415V, but nothing to worry about. I'll have a look in my incoming box, but I'll be amazed if all three phases are there. My understanding is that houses in the UK are wired sequentially with phases down the street; whereabouts are you to have three-phase?
Yes, repeat no.
There are four overhead lines in my street. Every 1930s house is connected to the bottom line, with the upper three lines being distributed sequentially.
OTOH there is my mother's ex-house. The cable emerges in the middle of the basement of the 1857 four story house (walls 3ft thick in the basement, 9" on the top floor). How it got there was never clear to me. I was talking to the person who bought the house and took a year renovating it. Apparently it has all three phases; no idea why, and I believe they are still only using one.
Would be nice if we had 3 phase residential service over here. Electric motors would be more efficient and such. Instead residential service here is a single phase drop to a center tap grounded transformer. 120V hot leg to ground. 240V across the hot legs. It's called "split phase" service. 3 phase service typically businesses only.
An old gray beard with an attitude. I don't bite.....sometimes
Three phase residential supplies are rare in the UK. Blocks of flats may have 3 phase. Industrial sites will have it. I've come across a couple of more or less normal houses with 3 phase. One I looked at with a view to buying, was built against a hill. In the bottom storey was a room in which a big lathe and a couple of other sizeable machine tools has been installed at one time. God knows how they got them down there and removed them. They must have used a crane.
Probably, most houses on most streets could have three phase installed, but it would cost a fortune.
EC8010 wrote: ↑Thu Nov 20, 2025 2:00 pm
Oooh er! Hadn't considered that. Anybody buying aged test equipment for its valves is an idiot; if not worn out, the valves will be well on their way. Would I buy a DMM using nixies? Not really; I want better accuracy than was achievable in that era. I can't imagine much useful test gear is lost to that cause. I know the late Jim Williams favoured a valve oscilloscope but I can't imagine any valve test gear would be useful today. I await a frenzied response telling me how wrong I am.
I wouldn't argue against your position strongly, although I do have two or three pieces of TE using valves or Nixies. I don't use them much and I certainly don't seek out TE like that these days. Valves can throw up unexpected results when you put them on a tester. A grotty looking octal with the envelope taped to the base very often performs at the top end of its spec.
However, there are one or two members here who are into Tek 500 series, vintage HP sig gens and such, and they've sometimes bought things which have been ravaged by valve strippers. They might see the world differently to you.
Getting back into playing with vacuum tubes for audio amplifiers is what initially led me down this test equipment collecting rabbit warren. Being on some of the DIY forums led me to purchase an HP 3562A Dynamic Signal Analyzer. This led me to the HP mailing list, where members at the time happened to be bitching about nixie tube rapists buying and stripping counters for their displays and scrapping the rest. I then perhaps foolishly bought a 5245L from the 'bay to 'save' it from the vultures, and this reignited interest in nixies (had played a bit with them back in HS in the early 80s). I started seeking out OTHER HP stuff with nixies, then expanding my interests to TE in general and now have a house on the verge of collapse.
As for usage, the HP 3439A and 3440A DMMs are permanent fixtures on my bench and get frequent use and the others come out to play occasionally as well. The other workhorse DMM is a Data Precision 3500 with a Panaplex display. If extreme precision is needed the 3455A or 3456A come out, but for day to day use the others by and large suffice.
The counters are largely for their cool factor as I don't typically have a huge need for frequency counting (though I am really afraid to actually count how many are lurking about here...), and my 5340A with nixie display has option H1, extending its top end from 18 to 23 GHz, so it's quite capable.
For my tube audio stuff, I normally use 'regular' tubes, and don't pretend to be an audiophool who can hear the differences between gray or black plate 12AX7s, or that 6DJ8s expand the sound stage and make the highs higher, the lows lower and cure cancer so no 'tube rolling' goes on here. 6DJ8s belong in Tek scopes and other test gear, and it infuriates me when people try to sell stripped carcasses.
-Pat
So... have you started collecting the parts to build a UniLoader to complete your "estate"...? Your survivors will be glad you did...
I'm a brit but SWMBO / XYL is a California girl.
