Member postings for James Alford

Thank you for all of the replies and suggestions. On balance, I shall not attempt to rebore the centres of the stones. Aside from the comments which have confirmed my fears regarding safety, I would have to buy more equipment to do the boring which would outweigh any savings from buying new wheels. I shall make some new supporting washers and address the wobbly circlip on which everything locates. If that still doesn't work, I shall look for new stones .

My grandad, who was a very good engineer, dinned nto me the need for cardboard washers either side of the stone. It is a lesson that for some reason really stuck. However, the reminder was was appreciated.

Edited By James Alford on 13/05/2022 17:32:02

Thank you for all of the replies, which have confirmed my suspicions.

I have just had a good look at the machine again and mounted the wheel without the pressings and nipping it up lightly. Turning it by hand, it ran nigh-on true. I also realised that the mounting flanges butt up against a wobbly circlip, not a turned collar, again not helping.

Methinks that I shall be making some modifications to the flanges.

Thank you for the advice.

James.

Thank you, both.

John: that is what I had suspected, to be honest. Replacement wheels seem to start from about £11.00, but the reviews of most that I have looked at all seem to complain of them being out of true.

Diogenes: That is a good point as well. The washers are stamped, whereas my old, long-dead Black and Decker from the dark ages had substantial machined flanges.

Regards,

James.

I may be on a hiding to nothing, but it is worth asking the question: has anyone successfully re-bored the hole in the middle of a grind wheel and, if so, how? The only tool that I have that is large enough to hold it is a bench drill.

Both of the 8" grind wheels which came with my bench grinder are so badly bored that they both run out of true side to side so that they make the machine unpleasant and, probably, unsafe to use. With just a wire wheel on it, it is smooth and silent in use.

The holes appear to be bored at a slight angle, making the wheel sit twisted. They are also a little larger than the spindle, but not large enough to sleeve, meaning that they wobble even more.

I have had the tool for too long to return it to Wickes for an exchange.

Regards,

James.

Edited By James Alford on 13/05/2022 07:24:12

Edited By James Alford on 13/05/2022 07:25:07

I suspect not. My inside walls, admittedly lined with flake board, are painted with white emulsion and the outside is painted with Cuprinol garden paint .

I think that you are right. I do have a small computer fan over the vent holes in the apex, intended for use if I a using any noxious materials in there, but I have yet to turn it on, as much as anything else because the whole building acts like a resonating box and it is surprisingly loud.

James.

I have a 17' by 19' wooden garage which is used as a workshop. Whether it is luck or not, I do not know, but it gets no damp or condensation.

The walls and doors have foil-backed bubble-wrap insulation stapled over them with flake board on top. The roof is unlined. There is a modest amount of ventilation under the eaves and around the doors which are a "comfortable" fit. There are also a couple of holes drilled in the apex.

The wooden floor is up off the ground, standing on beams. I put a sheet of plastic damp proof membrane over it and covered this with hardboard and those cheap inter-locking rubber mats.

Originally, I also lined the roof with polystyrene covered with hardboard. This was a major cause of damp and was soon removed.

It is not the warmest place on Earth, but it is dry and damp free.

Regards,

James.

Edited By James Alford on 18/03/2022 09:21:43

Edited By James Alford on 18/03/2022 09:22:19

Edited By James Alford on 18/03/2022 09:22:43

In the 80s, there was a sign in a toilet somewhere on the south coast that read something along the lines of: "To avoid consumption, please do not spit." This conjured up all sorts of disturbing images until I learnt that consumption was another word for tuberculosis.

James.

It is good to hear how you addressed this niggle with the Flexispeed. I would be interested to hear whether the accuracy of the tailstock has been affected by reaming it out. As an observation, there is a threaded hole on the top of the tailstock, just at the front. This should have a screw in it to stop the tailstock barrel from rotating when you are drilling. I found that taking time to make a screw that fitted the slot in the tailstock barrel snugly made a large difference to the ease with which it drilled.

James.

Thank you for the suggestions. The idea of using plaster of Paris to support the mould is a good one one of which I had not thought.

I had not considered using silicone for the actual mats as the only silicone I have encountered it is too fragile to stand up to that type of use. However, I shall look at the suggested supplier to see whether there is a more robust style that would be appropriate.

Thank you.

James

A slightly unusual question, perhaps, but has anyone any experience using casting or moulding rubber? I wish to try making some rubber mats for an old car; the type that mould over and around the transmission tunnel. I have been looking for a suitable product to use and am considering Devcon Flexane 80. However, it would be good to hear from anyone who used this, or a suitable alternative product, before spending £80.00.

Regards,

James.

Thank you, Robert.

I was curious about the strength of the magnet. A quick test shows that it can easily lift up a 4g nut vertically from a distance of 0.5cm. With levers, this should be enough for my purpose... with luck.

Regards,

James.

Thank you for all of the ongoing suggestions.

Just to clarify any potential confusion that I may have caused:

For the clock that I am trying to design, there will be one electro-magnet operating a set of levers which will operate one wheel. There will be a separate set each for the seconds hand, another the minutes and so forth for the hours, AM or PM, day of the week, 1/4 strike and hourly chimes. Other than the hours and minutes, each other time division will have a separate dial, like a regulator.

The picture below is the type of electro-magnet that I am proposing to use and have bought.

Regards,

James.

I decided against the coaxial approach quite some time ago, to be honest. From memory, each wheel was smaller than the one in front of it. Each wheel was in a case with a small slot at the top. The seconds wheel had a short arm protruding backwards. The arm had a pawl hanging down and this engaged with the exposed tooth on the minutes gear and dragged it around. When it reached the case, the case disengaged the pawl until the next rotation. This was repeated for the hours. It was all becoming too complicated so I gave up.

Regards,

James.

Thank you, again, for the suggestions and links, which I shall read, especially about the Lavet motor.

I did consider stepper motors at one time, but having written the code for the Uno and built the circuitry, I am inclined to stay with solenoids, unless there is a way to operate the stepper motor with the existing code. The code simply sets an output pin on the Uno to "on" momentarily when something is required to operate.

Duncan: your idea of coaxial gears is not dissimilar to an earlier thought that I had, which used coaxial wheels, one being pulsed each second and pins on the seconds wheel dragging the minute wheel around each 60 seconds, the minute wheel doing the same for the hours and so forth for the days of the week as well.

Regards,

James.

Edited By James Alford on 29/12/2021 10:19:45

Edited By James Alford on 29/12/2021 10:29:48

A small world: I bought one as well a week or so before Christmas. About £13.00 on Amazon.

Thank you for all of the suggestions. I should have given more details in my original request.

On and off, over a couple of years or so, I have been playing around with plans for a clock which uses solenoids to pull levers which will, in turn, pull the the clock wheels around. There are multiple solenoids, one each for the hours, seconds and minutes hand. The solenoids are controlled by an Arduino Uno.

I plan to make the mechanism from brass, but with magnetic pads for the solenoids to attract. I shall need to keep the weight to a minimum as the solenoids are quite low power and will need to overcome the weight of the mechanism and pawls. Maintaining an air gap is a good idea and should be easy enough to include in the design.

Regards,

James.

Hello.

I wish to make some levers to be operated by electro-magnets. The electro-magnets are a small version of the type that are used to hold open doors. What would be best metal to use for the pad that will be attracted to the magnet? I know that some types of metal retain less magnetism than others and are more suited to this use, but I cannot remember what. It is somewhat annoying, really, as I used to work with solenoids and electro-magnets all day long at one time and simply cannot remember.

Thank you.

James.

I started down this route on my Flexispeed at one point. I bought a tailstock arbour from Peatol Tools to replace the entire arbour in the Flexispeed tailstock. They are both the same outside diameter and the Peatol part fits the Flexispeed snugly. It cost very little, has a dead centre turned ground on the end and a thread for a standard drill chuck. I never completed it, simply because I managed to cure the problem that I had had with the original taper arbour. However, it might be cheaper that a Cowells part.

Regards,

James.

Edited By James Alford on 23/12/2021 10:33:18

Does this help?

James.