Member postings for Glyn Davies

I have tried this, using this article as a guide: **LINK** and got good results, with or without the dye.

I bought the black dye as crystals from ebay, a Chinese constant current power supply, also from ebay, used roofing lead as the cathode and aluminium MIG welding wire to hold the components being anodised. I modelled the components in CAD to calculate the surface area and hence the required anodising current.

One thing that surprised me was how effective the anodised layer is at not conducting electricity - touching the surface with the ohm meter probes shows infinite resistance. But dunk the item in caustic soda for a few seconds and the anodising is gone and conductivity returns.

Apart from all the stuff you need to do it (tank, power supply, battery acid, dye, lead cathodes, work holders etc) what I found a faff was the time required for each stage - anodising, dying, sealing. That's about three hours to do one small component. I'd consider making the part out of black Delrin if you can and save all the trouble.

As an additional precaution, I firstly slacken the bull wheel grub screw, then adjust the spindle bearings and then tighten the bull wheel screw to give the correct drive pulley end float.

Just had another look at your pic - it looks as though R and P are the centrifugal switching connections - there should be zero ohms across them. It also looks as if blue and yellow are the ends of the start winding and red and black the run winding. Confirm with an ohm meter. If so, you should connect the red/green cap wire to R, the red wire to U1, and the black to U2. You then need to connect the live run supply to U1 and the neutral run supply to U2. The live start supply goes to P and the neutral start supply to the yellow wire. Hopefully one of the screw studs is not connected to anything in the motor and can be used to connect these two.

If you don't have a reversing switch, bridge U2 and P and connect the yellow wire to U1. Then connect the live from your switch to U1 and the neutral to U2.

If you follow these instructions, stand well back when switching on.

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Edited By Otley on 05/06/2018 20:28:25

Edited By Otley on 05/06/2018 20:52:55

I was faced with a similar problem when trying to wire an imported motor to a Dewhurst reversing switch. I hadn't appreciated that both sides of the start winding centrifugal switch are connected to terminals in the connector box. In my confusion, I managed to wire the incoming live and neutral across the switch. Not a good idea.

The basics are that a capacitor start motor has a run winding that has a resistance of 3 ohms or so and needs a live and neutral across it. The start winding also needs a live and neutral across it but has a slightly higher resistance and has a capacitor and a centrifugal switch in series with it. Swapping the live and neutral across the start winding reverses the motor direction of rotation. In my case, one of the loose wires was one end of the start winding and the other was a short wire from the output side of the centrifugal switch. I therefore needed to make two soldered and heat shrink sleeved connections - wire from switch to capacitor and capacitor to start winding. The two pairs of lives and neutrals could then be attached to four of the terminal posts.

If you see what I mean...

In your case, it looks as though the run winding is connected to U1 and U2, but why you have three loose wires as well as the cap wires is a puzzle and you might need a ohm meter to figure what's what.

I haven't used it because I just have too many vices...

I had a thorough workshop tidy-up recently and came across this bench vice. I gave it a bit of a clean and took a photo. It was made from solid chunks of steel in the apprentice workshop at Automotive Products at Leamington, where I spent some time at the start of my engineering career back in the seventies. Just wondered if there was any one else on here worked there?

The apprentice workshop was one of the best equipped I've ever seen and is a sad loss.

Another take on similar lines - this is a piece of 4mm ply with a lath glued and nailed underneath and the topcovered in B&Q sticky-backed plastic sheet:

Thanks for the replies - just what I was after! My trembling finger is now hovering over the Pay Now button on the Amazon site for a Motorola G5S. The casing is CNC-hewn from a solid billet of space ship grade aluminium, apparently, and that's what's persuaded me.

Quick supplementary question - my current phone is on a Tesco pay as you go tariff. Will I be able to transfer the number to my new phone?

My wife has been pestering me recently to buy a smart phone – i.e. one that I can access the internet with. I have a mobile phone but the 8 key is a bit sticky, which makes texting words that have T,U or V difficult.

My normal method for accessing the internet is via my desktop PC with its 22” screen. My wife’s smart phone is too big to easily fit in my pocket and still doesn’t seem to have anything like the capability of my PC, but is that a sacrifice I need to make if I am to move with the times?

I’m looking for advice on how to proceed from anyone of a similar outlook to myself. What physical size phone have others gone with? 16Gb or 32Gb or more – or less? SIM only or pay as you go? How much to spend? Etc. Any advice welcomed!

Thank you.

A MOELLER T0-4-8213 cam switch costs about £27 from RS or Farnell and will fit in the Dewhurst switch housing.

There are sixteen terminals on the switch body, four pairs of which were already linked by Moeller. You need to add additional links as follows: 1-7, 3-5, 9-11, 13-15, 4-10 and 8-14. The switch wiring is then Live in to 2, Neutral in to 6, motor start winding Live to 9, motor start winding Neutral to 13, motor run winding Live to 1 and motor run winding Neutral to 5. You may need to swap 1 and 5 to get the motor to run forwards with the switch set to forwards.

Thanks - very interesting. I visited the Chester showroom and asked about delivery. It was £100 extra to the ticket price and kerbside only. Warco seem to include delivery and a man with pallet trolley will get it somewhere near your workshop. I think I'm tending more towards green than white at the moment.

I haven't visited Warco as it's a bit far, but probably will before I make what is still quite a financial commitment.

I had a look at the SPG site and could only find a 21mm spindle bore lathe?

Hi. As per title - I want a 38mm spindle bore lathe and have narrowed the choice to the Warco GH1236 and Chester Crusader. Can anyone advise the pros and cons of each?

Thanks

Thanks for the replies - a 4" embroidery ring might do it. He went to the vet last week and a sample of poo checked out ok. He prescribed antibiotics and ranitidine and we were advised to feed him rice, pasta and cooked chicken. He goes back to normal dog food today (to his disgust).

My first job in the morning is to walk our 2 year old border collie around the estate so that he can 'make himself comfortable'. Unfortunately, he's recently developed chronic diarrhoea, which is difficult to scoop up with a hand held poo bag. I need something like a child's tennis racket with the mesh removed and some means of supporting a poo bag so that the stuff falls directly into the bag, not on the pavement.

I thought that surely such a device must exist, but cannot find one. Can anyone suggest anything that could be easily adapted to support a poo bag so that the bag can be easily removed and tied up and a fresh bag fitted ready for the next event?

Thanks

OK, sorry - I misread your post.

I think the Chinese dimmer I've ordered has a similar circuit to that - I can't see anything in the one in the link that has any motor speed feedback?

The tool post grinder motor has a no load speed of about 18,000 rpm and is fine for grinding chuck jaws (its original purpose) but too fast for any milling or drilling. I was hoping that a triac based controller would give a kind of PWM output that would maintain the motor rated torque down to low speed.

The dimmer and switch have cost £6.29 and I'll spend a bit more on box, flex and trailing plug and socket but the project will provide a little interest and education, so I'm happy.

Thanks for the replies. To XD 351 - I had assumed that with the dimmer set to max, it would still not give the full 240v to the motor - hence my three way switch. I'll check the max dimmer output voltage and see it is 240; if so I'll ditch the rocker switch.

Hmm... I've just been reading through what I've written and realised that most household appliances (or light bulbs, at least) only use a single pole switch on the live supply, leaving neutral continuously connected to the appliance. So my proposed arrangement will be just the same.

Could someone please tell me when DPST switches are used on appliances to switch both live and neutral?

Hi. I want to make a speed controller for my tool post grinder that has a series wound brushed AC motor. I have ordered from China a triac based dimmer switch as the basis. I have also ordered a three way (on/off/on) DPDT rocker switch that I want to use so that the motor is either off, on full speed or on reduced speed.

The circuit I propose to use means that the neutral will not be switched, so that with my rocker switch set to off, there will still be a continuous neutral path from motor to house wiring. Will this be a problem?

Thanks