Here is a list of all the postings Martin W has made in our forums. Click on a thread name to jump to the thread.
|Thread: Telephone / Internet Scams|
This morning my wife answered the phone to be greeted by someone, a male, who claimed to be a police officer. The conversation went along the lines of, 'Sorry to disturb you but are you xyz etc., which of course was correct, as any fool could find that data on the net if they wanted. He then went on to say that 'We have arrested some people in London and found in their possession a VISA credit card in your name'. My good lady being pretty streetwise asked, before entering into any conversation with aforementioned "officer", to identify which bank/building society the card had been issued by.
This proved too much for "said officer" who immediately hung up. What amazed me is that he didn't just reel off a high street bank as a wild shot; not the brightest con artiste out there evidently.
So be warned they may start to smarten up their act, but knowing my good lady they will meet a brick wall when it comes to her supplying any important data; still sharp at 70 plus.
|Thread: What are you using for Lathe Way Oil?|
I oil when the slideways start to lose their film of oil and use Mobil Vactra No 2 Slideway oil. To date the beds have never shown any signs of rust/corrosion and a litre lasts for well over a year.
|Thread: What do YOU call it?|
Just Modging About or Furgling Around, often while like others I try to remember why came to the workshop and should I have a revelation then trying to remember where the required tool/item is. The latter rarely happens and if it does then reason for looking has vanished into the unfathomable mists of forgetfulness in the remote corners of my brain.
|Thread: North West 200 coverage|
I have never heard the expression 'circuits round the sun' but for me it puts a perspective to time that I hadn't thought of before. Thanks.
Perhaps I should get out more while I have a few circuits left having run up a mere 75.
|Thread: Anglepoise Lamps & CFL/LED lamps|
You can get get LED bulbs that are practically identical to the old incandescent bulbs in weight and looks, like these, which in warm white is not tiring on the eyes as the whiter varieties can be.
|Thread: Changing Broadband|
Well I have got Virgin cabled broadband and in general I have found it fast and reliable. On the odd occasion when there has been a fault I have always managed to get to get through to a 'representative' within a few minutes albeit in India or similar and they have always been extremely helpful. On one call where they couldn't help I was transferred to a UK engineer who was brilliant. I have always been polite and friendly and have invariably had the problem resolved. I wouldn't consider changing to any other provider and NO I don't have any connection, electronic types excluded, to the supplier other than being a very satisfied customer.
Credit where credit is due.
|Thread: LED replacement bulbs|
While it won't work on all LEDs I have got round the problem of using a mix of incandescent and LED bulbs on the same circuit. The average dimmer needs some form of load to operate correctly and this can be obtained from the incandescent lamps. My solution was to fit an even number of LED to incandescent lamps, we have 6 bulb ceiling fittings so it is 3 of each alternating. It has an interesting effect as when the lights are dimmed the incandescent lamps turn, as expected, much more red while the LEDs just dim while maintaining their colour, again as expected. The mix of lights tends to give a better less warm light when they are dimmed than incandescents on their own.
|Thread: Soft Feel Finish on Radio|
Isopropyl Alcohol can be bought from CPC (Farnell) in either 400ml aerosols or 1lt cans. I always have some around for general cleaning as it leaves a smear free finish and does not attack most plastics though it will affect some paints. It's also good for removing emulsion paint after it has dried, as is methylated spirits, which it useful for cleaning those bits you didn't really mean to paint.
|Thread: Turning over a new Leaf|
Welcome to the madhouse that said there are a whole pile of people on here who will be only too pleased to give you sound and valuable advice. I know that there will be interest in your pictures and videos and once here they could well be of benefit to others.
|Thread: Mini lathe|
If the speed control board drives a similar motor with no problems then the problem is the motor. I take it you are using a Digital Multimeter to measure the volts across the motor and this can give erroneous readings when measuring switched waveforms, even the so called true RMS meters as they are limited to a range of form factors (waveform shapes). If the motor is not running smoothly then as Neil suggested it could be the brushes or the motor connections to the brushes, shorted turns on the armature, carbon build up around the brushes causing tracking to earth. As I said above If the electronics drive another similar motor without any problems then the fault is with the motor.
|Thread: Smoke detectors|
The domestic smoke detectors I have running and those which have been replaced are/were all 'ionization' devices. The one near the kitchen had an override as it will activate from fumes from the cooker grill/oven when there is no smoke in the air. That said I haven't checked on the latest domestic alarms to see if they have changed the type of sensor used.
Just checked the Screwfix site and they are now offering a full range of detectors including heat and smoke combined. Tomorrow I will purchase a couple, offered in pairs, to fit near the kitchen or even have one in the kitchen. Thanks for the heads up.
Edited By Martin W on 24/03/2019 11:32:18
|Thread: 24v dc motor powering a drill press|
There is no need for a transformer as you can buy switched mode power supplies here. They have 24V DC units with output currents that will easily meet the 11A input current for under £30, a 24V 20A DC smps is listed at £28-99p postage included. All that is then required is a speed controller that can handle 20A or so and the jobs done. No need to try and build your own and spend a fortune on large transformers, bridge rectifiers, capacitors and a suitable case to hold it all. Just 2 relatively small units that can be mounted in a smallish enclosure.
A suitable speed controller can be found here
Edited By Martin W on 22/03/2019 01:29:19
|Thread: Brazing after milling whilst preserving accuracy|
You say that the type holder is subjected to repeated heating and pressure cycles. I take it that this happens when tools are used to fix the gold leaf or substitute on the book covers/spines, what is the typical temperature that the print holder is heated for this transfer process? I assume that for the smaller type holders the pressure is only applied by hand and not in some form of mechanical press. The reason I ask this is that Ian has suggested the use of adhesives and these could fail if the tool working temperature is high.
|Thread: Pitched aluminium rings. Any ideas how to machine them?|
Just printed out one of the photos showing the bezel ring edge on and measured the angle of the bezel to the base and this gives an included angle of 22.5 deg. Before anyone jumps up and down I know that this is not the way determine the 'true' angle on the bezel. I think that SOD by offsetting the top slide by 20 deg actually cut an included angle of 70 deg rather than 27 deg and this would account for SOD's bezel looking very different from the pictures. That said Dave clearly illustrates one method of producing the particular part on a lathe which is what Christopher wanted which was the point.
|Thread: Is it a drone?|
They are already being used at airports to scare other birds away, not a in seagull form but as a mock peregrine falcon that perfectly mimics the falcon's flight, glide and attack characteristics. A brief clip can be seen here.
|Thread: Spring Calculation|
Wasn't there an article in MEW sometime ago about springs, spring winding and calculations for achieving the required force, or have my grey cells finally petered out ?
|Thread: Proxxon MF70 went bang|
Not at all in fact it was FF's comment regarding and I quote, "Amidst all the electronic experts here, this will be inviting ridicule but...."
With regard to your posting I agree that using a neon indicator severely limits any meaningful tests being performed. However if this is all Bill has then use can be made of it to see if the mains supply is reaching the mill and whether physical switches are working. It may also be possible to identify, on the live side of the circuit, where there is a break i.e. Dave suggested that one of the inductors may have failed and it could be possible to identify a fault of this nature using a neon based tester. It's a case of using what is at hand to help eliminate or confirm any problems.
Hope this puts your mind to rest.
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.
FF carbon brush dust build can cause problems but most of the dust is deposited in the motor where it can provide a leakage/short to earth and this frequently causes an RCD trip. If you look at the pictures Bill has posted the actual speed controller board looks to be be reasonably clean and free of any significant contamination. That said I feel that any contribution is welcome as it can make people look again at the problem and this sometimes proves to be very useful.
I think that anybody who just dismisses another's comment as stupid or rubbish not only show themselves up but do a disservice to the forum and can make others hesitant to make a contribution.
As far as the pictures show the motor doesn't seem to have been over stressed, commutator and windings look to be OK as far as it possible to see and the same applies to the circuit board. I am wondering if it isn't, as earlier suggested, a failure in the mains supply cable near or at the point it enters the head. If this is the case then the machine fuse will have remained intact and the plug top fuse would have taken the brunt and could have blown with an audible pop. This would also fit in with the motor occasionally stuttering prior to the failure as the break in the cable intermittently failed. If the plug fuse has blown then without having the ability to check the cable with a meter it may be worth replacing the supply cable and trying it again to see if there is any response. Another way would be to use a mains indicating screwdriver/tester and after replacing the plug fuse see if there is any indication of the mains being present at the circuit board, no need to say really but just be careful when working on exposed mains.
Another possibility is that there has been a failure of the mains switch on the machine which could, remote chance, of shorting something to earth or may have just failed internally with a bit of arcing hence the smell and failure to run.
Edited By Martin W on 31/01/2019 17:48:17
Edited By Martin W on 31/01/2019 18:07:41
Again here is another site with the circuit diagram plus a picture of the pcb identifying the components. Dave beat me to posting as I was rummaging through other pages on the net looking for any other data/information, at least it is not the same site as he has identified.
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