I wouldn't bother using the change wheels to get a feed rate as that needs to be variable......a better way would be to fit a small 3 phase motor to the other end of the leadscrew and drive it with a VFD which is very variable.
I've seen lead screws driven by stepper motors and speed controls, which I gather work OK. 3 phase motors tend to be very large, and I guess an expensive option. The fine feed tumbler gear does have some control through the VFD. Cheers Nobby
Hello Nobby, I’ll be interested in hearing about your gear lubrication goes. I’ve been using Vactra way oil on my Super 7 gear train because it has some tack; this seems to reduce slinging. 👍
Hi, I've been recommended to use EP90 gear box oil. The oil recommended by Myford is probably too light. I'm going to give it a try. Will let you know how I get on. Cheers Nobby
Hi David I have lots of projects lined up for the Myford. Now the motor is so much quieter, I notice the noise from the change gears more. I use SAE30 oil as recommended by Myford, but I've been told grease may be better. What do you think? Cheers Nobby
@@nobbysworkshop Hi Nobby. SAE 30 oil is thin for gears. Pop along to Halfords and get yourself a squeezy bottle of EP 90 or EP 120 Differential oil, they are thick. I say squeezy bottle as they used to be a tall round bottle that had a long tube on so you could lay under your car, remove the filler plug and squeeze the bottle upright and force it up the clear tube. I seem to recall that they were 400 or 500 Ml size. You could try grease but you might get a squelching noise as the gears run. Good luck, let me know what you decide and how you get on. Regards from Australia.
Hi Nobby. This should give a better finish with HSS tooling, but with carbide the original medium speed gear will be better in most cases. As Kev pointed out, a QCGB is really by far the best solution to vary feed rate and will do it in seconds. The trouble with being set in fine feed is that it takes forever to get jobs done. A QCGB allows you to rip metal off fast without regard to finish, and then quickly switch to finer feed for finishing. Cheers Rob
@@Xynudu Hi Rob, I agree with you and Kev, a gear box would be ideal, but way beyond my pocket. I've often looked at used ones, but they are generally more than I paid for the lathe. Fortunately the tumbler gear is fairly easy to switch over if the job requires it. Thanks Rob. Cheers Nobby
@@nobbysworkshop Hi Nobby. I had a look to see what QCGB the Myford uses and it appears to be a Norton as OEM. I suppose they charge a lot for them as a stand alone because there would only be a few available units from scrapped lathes for what would be a popular item. Cheers Rob
@@XynuduMyford list them new at about £1674 used ones on eBay from about £700 from scraped machines. My lathe clutch came from a scraped lathe. Took a long time to find one I could afford. I'm more than happy with what I've got now. All the best Rob. Cheers Nobby
Hi Nobby the Tufnol / paxolin gears are designed as a weak point so if you crash the lathe carriage they will strip the teeth off and prevent any serious damage. Let’s just say I have tested this feature 😳
I should have mentioned that Julia. The change gears seem so much noisier now, but I guess that's because the new motor is so quiet. My mini lathe has nylon gears, and some years ago the lead screw jammed and stripped a gear. Fortunately not too expensive to replace, but put the lathe out of action for a week. All part of the fun 😕 Cheers Nobby
@@julias-shed I've been using SAE 30 oil as recommended by Myford, but when I got the lathe the change gears were covered in thick grease. Grease is a bit messy, but maybe the answer. Thanks Julia. Regards Nobby
nice explanantion Nobby if you ever get chance of the quick change gearbox snap it up, there a godsend, i know there expensive, but never lose there value. Makes life on the lathe very much easier. see you next time👍👍👍👍👍👍😉😉 Kev
Hi Kev. Yes, definitely gotta have a QCGB on this sized lathe. Makes turning much easier and faster. Fine feed is great for HSS, but not for carbide. Most new lathes this size come with a QCGB as OEM. Cheers Rob
@@MrFactotum I will keep a lookout Kev, but the used ones I've seen are way too expensive for me. Myford still have them new, but they are more than twice what I paid for the lathe. Cheers Nobby
Nice upgrade Nobby 👍 Something to note; in most cases it's ok to over speed the motor if it's a 4 or more pole (1800 RPM or less nameplate) It requires increasing the frequency range output to say 90 Hz on the VFD. That way you can run a lower belt drive ratio and have less torque loss at the lower speeds and still retain the higher speed range. If you have a local VFD guru buddy, might worth offering a pint or two to help with the setup 😁😁 Cheers....ATB...
I've been testing it out over the last few days Rob. The job we all hate is parting off. But this motor seems to handle it really well. As you'd mentioned, being able to monitor speed change under load is also useful. I'm really enjoying the new setup. Cheers Nobby
It's going to make such a difference to the lathe Julia. So much quieter. I have another little accessory to add, which I hope to show on Wednesday. Looking forward to the first project. Cheers Nobby
Nice work Nobby, that should be a lot more convenient to change speeds. I wonder if an American Southbend lathe could be done like this? I know exactly nothing about 3 phase motors, wiring, vfd's.
@@jeff1176 You could always contact Newton Tesla Jeff. They have these Vfd'd and motors for other makes of lathe, and various motor powers. This one is a 3/4hp, and they have a 1hp as well. They are pre-wired so easy to install. Regards Nobby
You're absolutely right there. I looked back at the footage, and the switch did seem to be on the wrong side. 😕Need to remember that in the future. Thanks for pointing this out. Cheers Nobby
Well done Nobby, I am sure you will enjoy it. I put a rubber glove over my clutch lever because I kept going for it to stop the lathe, out of habit 😂 I have removed it now I am use to the new controls. 👍
You've certainly gained a super lathe from the lovely upgrade Nobby, good luck with putting your workshop back together before you get to play with the new toy.
It's going to make such a difference being able to instantly stop and start the motor, and change the speed while making a cut. Looking forward to my first project on it Bryce. Cheers Nobby
You have certainly advanced a tech level with that vfd set up! I am lucky as I have three phase in my workshop. You may find that the vfd motor does not produce as much power at lower rpm as you would have by changing speeds through belts, but no matter as you still have the option of running the motor at higher speed and swapping belts! Be careful not to exceed the max speed of the chucks and the lathe headstock bearings! You certainly have a lot in a small space but it looks like a very neat and well equipped workshop! Phil, “Phil whitley, my week this week” on RU-vid.
Thanks Phil, I'm so pleased and grateful to have this. Thank you for your advice. I'm going to give the new setup a test to compare with the old motor, which I believe was also a 3/4hp. I guess the real test with be parting off. Regards Nobby
Great Outcome Nobby. So glad that you are pleased with it and hopefully will get plenty of use over the coming Years. On your next visit to Lidl, have a nose around at their cake / sandwhich boxes. You may find one of a suitablw size that you can cut about and fit it as a lid over the buttons panel. Take care. Best Wishes from Australia.
Thank you David. I'm very pleased with how it turned out, and all due to you. Good idea on a plastic box to cover the control panel. I have a project lined up to test it out. Regards Nobby
Hi Nobby, quite by coincidence my Friday video this week is the installation of my Newton Tesla 750, which I fitted a couple of months ago and it completely transforms the lathe, I did have a problem getting the old pulley off the old motor. Unfortunately mine wasn't a very generous gift 😂 I did have to make a chart to convert the speeds on the control panel to the pulley speeds on the Myford, so keep your tachometer connected. you will have far more control over your speeds with the new motor, I never use the back gear now, I did have a problem engaging the clutch and the motor cutting out, I did contact them and they never got back to me, but I never use the clutch now anyway. I find it useful when facing a large diameter to increase the speed as you get closer to the centre. Good Luck Mark
Hmm yes Newton Tesla are not good at after sales. One of the button caps on my unit cracked badly and I asked about how to replace it. Yes you've guessed it they never got back. I suspect that the warranty will fall into the same black hole. Oh and I fixed the cap with super glue!
I feel so lucky to have received this generous gift from David. I would not have one otherwise. I had replaced the motor pulley some time ago, as the old one was in very poor condition. It wasn't running true. I would certainly recommend fitting a tachometer to keep a check on the actual speeds. Can't wait to start using it. ATB Nobby
That is a really useful lump of kit! Can’t wait to see it in use! I am lucky in having a3 phase workshop, it makes a huge difference. Phil “Phil whitley, my week this week” on RU-vid
I count myself very lucky to receive such a wonderful gift Julia. It's going to make using the lathe even more pleasurable and peaceful. Can't wait to get it installed, and in use. Cheers Nobby
Hi Nobby. So glad that you will be soon be machining at the correct cutting speeds.😊 You will now be able to adjust the speed whilst cutting to get the optimum metal removal. No more tool chattering because you can not be bothered to stop and change the belt, just a turn of the knob. Looking forward to see it in action. Small warning, watch out that the key does not fly off when running it on the bench. Thanks for the shout out again, much appreciated. Regards from Australia
Thank you again David for your generosity and kindness to me. It was my pleasure to give you the shout out you deserve. I hope it brings you more subscribers to your channel. I'm sure it will. I did try to remove the key, but it was such a perfect fit, I couldn't shift it. Hope to show installing it in my next video. Can't wait to start using it. All the best to you David. Cheers Nobby.
I'm so proud to own it Jim. I dreamed of having one since my early 20s. Took me until I was 69 to get it. I'm 76 now and hope to pass on some nice machinery to my boys. Cheers Nobby
Hi Nobby. The way you've got it mounted works fine, so it must be right. That slight difference in speeds is very minor and not worth worrying about. LOL. My turning speeds are almost never correct and I still get good results :) Some people just get carried away with the technicalities and make life hard for themselves. Looks good to me. Cheers Rob
Thanks Rob. I'm perfectly happy with it. Testing it against my hand held tacho it reads the same. One comment was that there was no point in having a tacho on this lathe. But there is a method to my madness! 🤔 Cheers mate. ATB Nobby
@@nobbysworkshop Hi Nobby. I have a tacho on mine, left over from when I converted it to variable DC drive years ago and then back to AC. I find it handy to glance at and know what belt drive is set rather than open the cover and peer inside. Certainly does no harm having a tacho. Interesting to see how much the lathe slows down under load ;) Cheers Rob
@@XynuduThanks for that Rob. It makes me feel better about fitting it. Especially as I hadn't thought about a change in speed under load. Take care. Cheers Nobby
Unless you have a variable speed motor I cannot see the need for a tachometer as the belt/pulley arrangement will give the speed. Your correction chart gives the true speed. I hardly ever change speed on my lathe and usualy run at top speed, using tipped tools, top speed on my ML10 is 840rpm
If it works Nobby thats all that matters, there's always more than one way to skin a rabbit, and what suits one may not suit another; You know what Frank sang, "i did it my way" !!! great neat job👍👍👍👍 atb Kev
Thanks Matthew. I had thought of that, although they do tend to be very expensive second hand. If I could find one cheap enough I would consider it. The Tachometer kit was only £11 and I didn't want to pay £50+ for a cover 😂 Cheers Nobby
Hi Nobby. Great video. I mounted my Hall Sensor on the rear of the spindle. I 3D printed a collar to hold the magnet and clap over the rear nut. The sensor goes through the gear cover and is held in place by a combination of 3d printed parts with the readout above.
Thanks Paul. Probably less important on the Myford lathe as the speeds are pretty much present. But absolutely invaluable on the mini mill. Cheers Nobby
Those little tachometer kits are handy. I put one on my big lathe just because the selector handles can be a pain to decipher what speed the lathe is in. So the tach really helps.
That's right Tom. Although these Tachos only cost a few dollars, they are incredibly accurate. They give a clear check of the rpm, without having to think about it. Cheers Nobby
