Here is a list of all the postings James Jenkins 1 has made in our forums. Click on a thread name to jump to the thread.
|Thread: Drummond / Myford M Headstock Bearing|
Thanks for your replies. Yes, I have the additional bearing in. Would babbit be better than turning a new one from bronze?
I'll have another look tomorrow, I can hear the motor working harder than it was, so I am a bit nervous about tightening much more, but I didn't think I would get it better than 2 thou. Although I suppose it all depends a bit on how hard you are pulling / pushing to get a reading.
Apologies for igniting an old thread, but hoping I can get some advice.
I was turning some aluminium bronze last week and had a lovely finish, even with fairly heavy cuts. Decided to let everything cool, to take closer measurements and when I started up again I got a rotten finish. I decided that the headstock bearing must need adjustment, as I was never 100% happy with it. When I tried to tighten it found I couldn't get any sort of resistance, despite tightening it really quite hard (hammer on c-spanner).
I happen to have another old M laying around, so today I took out the front bearing in this and used it on the lathe, where I was indeed able to tighten the bearing, first so that I could just turn it by hand and then when the oiler was tightened down so that it turned with some slight resistance.
With this level of tightness I was able to get it so that a 9" wooden down in a large 3 jaw chuck could be pushed upwards so that the check moved up around 2 thou. This is cold.
Do the above settings seem about right? With the lathe be fine with another lathe's bearing in it?
|Thread: Lovely old surface gauage on ebay - how to make it!?!|
I was including postage in my head, I'll message them - worth a chance.
I need to dig out the chapter on worm gearing, but any suggestions on what pitch would be good for this?
Also if anyone is able to sort out my typo in the thread title I would really appreciate it!
Images here for ease and longevity.
I was frustrated to miss out on this small surface gauge that sold on ebay last night. I was rather unusual (at least to my eye) and also rather old by the look of it (111 years).
I'm thinking it would be a nice little project to make one, but the gearing used to fine tune the height is a new one for me. Presumably the tolerance between the gear teeth would need to be very tight, so as to not allow movement after setting. Any thoughts on making it?
Do you think the tightening screw on the side is just to hold the scribe point, or does it lock the gears, once the correct height is set?
A lovely little thing, but I didn't really want to pay £40 for it (I went up to £35) and no doubt the buyer is pleased with it too.
|Thread: Homemade Grinder Advice|
Thanks so much for your feedback, looks like I was on the right track the first time, so that's what I will go with.
I'm not happy with the results I'm getting freehand, so I will probably make the simple Harold Hall tool rest.
I'm coming back to this, as I need to get something in place to allow me to properly sharpen lathe tools and drill bits.
With fresh eyes and thoughts, I've started to wonder if building something is best use of my time and money. It maybe a good route, but I've been looking tonight at Clarkson Mk1 grinders for around £350/400. That might end up being £200 more, but obviously the time in building a grinder and then a rest could be put to other projects, and the motor on a Clarkson could easily be replaced with a solar powered DC unit.
I realise that a Clarkson is a very capable machine, so would hopefully grow with me and allow me, in time, to sharpen items that a home made setup couldn't dream of (e.g. reamers), but how easy is it to set it up to touch up a lathe tool? Do you end up spending hours on what should be a simple task, because it is so complex?
Also I don't have a surface grinder, so is it possible to use one of these for small surface grinding tasks?
All and any feedback very welcome and appreciated.
|Thread: L. H. Sparey Running Centre|
All my kit is imperial, so it's just more natural for me!
I should have said, if anyone would like a .pdf of this design please just let me know.
I have worked through L. H. Sparey's design and modified it for modern metric bearings. I have used slightly smaller ones than Jens Eirik, to maintain the same proportions as Sparey, but taken up the suggestion of an angular bearing at the front. This will be used on a 1MT lathe, so I didn't want it to become any bigger, already, sadly, some of the lovely proportions of Sparey's 2MT design have been lost.
One ideal I did have since doing the drawing is to put a small hole up the morse taper, so as to be able to knock the shaft out when it needs cleaning (obviously then re-turning the taper).
I would be interested in any thoughts you might have or suggestions.
|Thread: Lathe Vibration|
I ran the lathe yesterday, most of the day playing around and didn't really notice the vibration causing a problem. I was struggling to get a fine finish, but I think that's me needing to get a proper grinding set up so my finishing tools are less of a point and generally sharper. Plus the Myford/Drummond has a minimum fine feed of around 6 thou, which I have always found leaves ridges.
Yes, we have a battery bank, which gives us capacity once the sun goes down, but being my place of work I'm mainly there during the day. Yesterday, which was reasonably sunny, although late autumn low sun, the lathe was using 160w to tick over at 800rpm and 240w to take 10 thou cuts in 1/2 to 3/8" mild steel at the 6 tho feed at around 800/900 rpm. Using a die to cut a 3/8" BSW thread with the backgear required around 80w. The solar panels, were producing around 300w at the time I looked, so running the lathe and still charging the batteries. They have a theoretical power when new (they are ex-solar farm) of around 750w on the perfect spring day, at the perfect angle etc etc.
|Thread: Safety Switch/Circuit Design?|
Thanks so much for this - I will play around, but this looks like it should work well.
Thanks again - really appreciated and I will let you know how I get on.
Hmmmmmm guess I would need some sort off diode in there or else the motor would come on when the momentary switch was pressed.
Apologies, the foot switch is just on/off the potentiometer is a rotorary one on the control panel. The pedal control's real function is for stopping the lathe, sort of a deadmans handle. The system you describe would work, although the ideal, rather than a timer setting, would be that it reset on the pedal being pressed.
I did think, if I had a non contact relay, which had a 36v input and activated the potentiometer circuit, a momentary switch could activate the relay, then be replaced by a feed off the motor power (once the foot switch on the potentiometer circuit is pressed). Once the motor turned is turned off the potentiometer circuit wouldn't be activated again until the end momentary switch is turned on.
That's exactly what I'm looking for, but I just want the relay, so I can build it into the system myself. I don't seem to be able to find one. Obviously it would have to be DC low voltage.
I wonder if someone with a bit of electrical know how can help. I have my lathe working using a 36v DC motor, which connects to our central solar system. My usual system for any machine in the workshop is as follows:
Central workshop switch panel: Switch that activates the relay, providing power to the machine
Then at the machine itself:
On/off switch on the speed controller
Foot switch on the speed controller
Both of these are on the power feed going to the potentiometer
In other words, once it's on at the wall, you need to have the switch on on the machine and then press the foot switch for the machine to come on (likewise to turn it off just take your foot off the pedal).
So far, so good. However, I noticed today that for one reason or another there is less room for the foot switch at the lathe and, despite my best intentions, every time I stopped and fiddled with the lathe, I forgot to turn it off at the switch. This means that if I accidentally stood on the foot switch the lathe would come on. No I have it set to accelerate very slowly, so not the end of the world, but that's not the point.
So I would like to add a circuit/relay into the system that allows the following:
Turn on the on/off switch - activate potentiometer circuit
Turn on the foot switch - turn on lathe (by completing potentiometer circuit)
Turn off the foot switch - turn off lathe and deactivate potentiometer circuit
The circuit should not then turn on again until the on/off switch has been set to Off and then On (i.e. pressing foot switch shouldn't bring on the lathe)
I realise many will see such a system as being OTT, but I guess we are each responsible for our own safety and being a little absent minded I would rather have one feature too many, than one too less.
Has anyone got any suggestions on how to do the above??
|Thread: Lathe Vibration|
I have fiddled about and managed to reduce it quite a little, took some initial cuts today and I cannot see that the vibration is causing any issue. Which is good news.
Rather excited as I took the first cuts, with the sun beating down - using the free power!
Thanks so much for the advice and feedback. I'm going to have a fiddle about over the next couple of days and will feedback.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.