Member postings for Bill Phinn

I recently bought some M36 studding and nuts, which were advertised as "stainless steel".

Can anyone tell me whether the coding B7 BP on the end of the bar indicates a kind of stainless steel, or at least whether this bar looks to you like stainless steel.

Thanks for any help.

P.S.  Can anyone tell me how to get round the fact that when I insert images from my albums they often seem to flip top to bottom?

Edited By Bill Phinn on 08/02/2019 00:43:19

Many thanks, JRow and Roger.

Roger, I've tried pulling on the motor after removing the screws but there doesn't seem to be a hint of willingness to budge. I suspect I do have the older version. It seems I was wrong about having had the item eight years; I've actually had it over ten.

Many thanks to everyone for your replies.

Michael, the motor appears not to be seized if the free turning (by hand!) of the spindle and commutator et al. is anything to go by.

JRow16, on the plus side your double failure of an MF70 makes me feel less unlucky than I otherwise might have done, but it has virtually sealed my unwillingness ever to put money into a piece of Proxxon machinery again. Was this the place you ordered the motor from: https://www.fluidonline.de/proxxon-28481-19-motor-mit-stuetzring-fuer-ib-e-ibs-e-ersatzteil/a-5776/.?

If so, I'm not sure whether it makes any difference, but the part number is one digit different from mine (which ends -11, not -19). While we're at it, I'd be interested to know how you uncoupled the old motor; I did try removing the two retaining screws at the base of the motor but it seems it can't be lifted away unless the spindle locknut is first removed, and I'm not sure how that's done.

John Paton, I wil try your second suggested test this weekend, thank you. I'll have to desolder the motor terminal wires anyway if I'm to do Tim's suggested resistance testing.

Tim, it turns out my brother has a decent quality multimeter and he used it only yesterday to check the resistance on his newly installed underfloor heating; I could always buy my own rather than wait till I see him next. I will try your suggested tests as soon as I am fixed to do so.

Posted by Martin W on 01/02/2019 00:22:30:

Bill

If you can do it safely then test the point at which the blue wire is connected/soldered to the pcb with the power on. If the neon lights up then you would appear to have a break in the neutral line to the mill. If there's no reaction then the neutral should be OK and we can discount the supply cable for the time provide the plug has been wired correctly.

Martin, I have just done this test, touching the screwdriver tip to the solder at the back of AC wire. The potentiometer was turned all the way up and yes, the neon illuminated. You say this would appear to mean a break in the neutral line. Can you tell me in simple terms how we know it means that, and how I can trace the location and or cause of the break?

Incidentally, can anyone tell me why this message occurs, which appeared multiple times when I attempted to post this latest post, and has occurred frequently in the past: "Your posting is 112556 characters too long, please split it into two or more separate posts".?

Thanks, Martin.

I've attached two images showing the result of a neon screwdriver being held to each of the two motor terminals in turn. The fact that it lights up suggests to me a working circuit from the mains via the switch and control board. Does this necessarily mean either the control board or the circuit is healthy? I know it says nothing about the health of the motor.

Tim, I forgot to say, I tried the drill battery with an in-line fuse. It didn't power the motor.

Edited By Bill Phinn on 31/01/2019 19:05:27

Another photo of the windings:

Thanks for the further replies.

Andy, the windings are partly viewable. I've taken the best photos I'm capable of. I've also shown the commutator. The brushes are higher up than is really photographable, but they do look to have plenty of meat on them, although it's a little difficult to tell given the fact that most of their meat is hidden in the (spring-loaded?) holders. I've got to say I don't really suspect the brushes given the relatively short run time this machine has experienced since new.

Not now, but the acrid smell did linger for about half an hour after the event.

John, I don't know whether it's relevant but over the course of about one minute before the machine actually terminated, the motor stuttered a little and an intermittent gritty sound, lasting only one or two seconds each time, came out of the housing before the motor picked up speed again as normal.

Eta: Derek, there is no apparent sign of anything defective with the power cord where it enters the machine.

Eta no.2: John Paton, I can't smell smoke on the circuit board now but there was certainly a strong smell of burned something or other when the failure occurred.

Edited By Bill Phinn on 31/01/2019 14:59:34

Many thanks to everyone for your helpful replies.

I replaced the fuse at the outset with a new 3A and then a second new 3A just in case. No joy.

The socket outlet the machine was plugged into is working normally, at least as evidenced by its ability to power other devices.

I connected a 100W incandescent bulb to the motor terminals, connecting the negative terminal to the screw fitting on the bulb and the positive terminal to the foot contact. No joy.

I don't have a 12v battery to hand; my drill batteries are all 18v. I've tried using a 1.5 volt AA battery in the hope that this might produce a flicker of movement in the motor but there was no sign of any movement.

I'm afraid I don't have a multimeter and would be pretty clueless anyway about how to test individual components on a circuit board.

If there is anything obvious I might be missing and that my almost non-existent electrical knowhow might allow me to explore, I would be grateful for the suggestion.

Inspired brutality, Michael. Thank you!

Many thanks to everyone for your replies. It's very generous of people to be prepared to look at it in person. I live in Manchester. If it came down to it, I could put the (very small) machine in the back of my car and do the travelling myself. Incidentally I did try several times to add my location to my profile, but, in spite of pressing the save button each time, this change appears not to want to take place.

I've added some more photos here and in my album, which hopefully convey a tiny bit more information to the initiated.

I have tried to extract the circuit board with attached wiring from the housing so that we can see what we're dealing with, but the speed control shaft passing through the wall of the housing is preventing me from lifting things upwards and I can't see any easy way of removing the external knob from the shaft (I've tried gripping the shaft with needle nose pliers while pulling the knob away from it, but it is stuck fast). I can't fathom out another way of getting the circuit board out at present short of desoldering the connections.

I can't see any obvious blackening of internal components; only the copper windings glimpsed though the cut-aways in the motor body looks quite dirty, but this may just be accumulated dust.

Any ongoing advice is greatly appreciated.

Edited By Bill Phinn on 31/01/2019 01:36:22

I've had this machine for about eight years, but it's not had a lot of use in that time (easily less than 100 hours). Today I was milling some brass with it, and it had been in use for about five minutes when a loud bang and some smoke emanated from the motor housing. The machine stopped working permanently.

Does anyone have any advice that might help me to diagnose the cause of this and get it working again? I am ill equipped, in more than one sense, to do anything but the most basic fault finding of electrical items.

Thanks for any help.

Yes, the primary objection I've heard to laying the plane on its side is that it risks knocking the "iron" out of adjustment.

This guy knows a bit about planes and doesn't appear to lay them down on their side:

https://m.youtube.com/watch?v=gE4yVgdVW7s

Ady, assuming you have a road-going bicycle of some kind already, I would opt not to buy an exercise-bike as such, but a turbo trainer.

Turbo trainers take up less space, allow you to use your own bike (that you are used to and comfortable with) on it and generally provide a much smoother ride with more realistic resistance than a lot of the dedicated exercise bikes at the lower end of the food chain.

I own this one: https://www.cyclestore.co.uk/kinetic_road_machine_2_0_smart_trainer-ID_73443

but less expensive and perfectly competent ones are available, e.g. https://www.wiggle.co.uk/lifeline-tt-02-fluid-trainer/

In case you're wondering, I used to race competitively in a club, and had done for over thirty years, until an immune disorder (that developed a few years ago) confined me to slightly more sedate riding. But I still use my trainer quite a bit.

Bang on cue an example of another kind of machine "translation" at work: I use someone else's computer for ten minutes and their undisabled (unlike on my computer) autocorrect/autocomplete function obviously doesn't recognize or like the adverb "somewhat".

Would a compression spring (such as found on carburettor jet screws) between nut and screw help?

Mick, have you seen today's Airfix instructions? There appear to be no accompanying words at all. The pictorial approach is the way instruction leaflets/manuals appear to be going generally, and the loss of clarity in some cases is colossal.

Bad English translations in manuals won't change as long as corporate decision makers happen to be non-linguists, or at least people without the intelligence or humility to realise that translation is a specialised skill that you skimp on (and that includes handing over responsibility for it to a machine) at your peril.

I've done something of a study of Chinese-English translation and I can say with some confidence that generally speaking the only reliable translation work from Chinese to English done in the PRC is at the behest of central government.

On the UK/US lexicon topic and continuing the aviation theme, I do remember flying with American Airlines many years ago and being someone taken aback when we were nearing our destination and the captain announced we would be "landing momentarily". I caught the eye of my fellow passenger (who was also English) and said I hoped they would at least give us enough time to get off.

Two nations divided by a common language, still.

For some reason, jewellers never call precious metal filings etc. swarf; they/we call it lemel.

Thanks, FF, Nick and Clive.

To update, the retailer has agreed to give me a gift card by way of compensation, and the listing description has been amended to remove the claim that the vice as sold has "lockable slideways".

Edited By Bill Phinn on 22/01/2019 16:47:28

Yes, the fabrication method shown is rapidly being replaced by castings. The disabled jeweller is certainly very accomplished.

I've done quite a bit of claw setting, and hand fabricated quite a few collets in my time.

Here are some simple earrings I made a few months ago and took a photo of:

ETA: The photo was there for about ten minutes, but now isn't.

Edited By Bill Phinn on 21/01/2019 00:05:56