Member postings for John Shepherd

Anyone been to the show at Thornbury today?

We usually have some comments by now.

John Shepherd

Edited By JasonB on 14/08/2015 20:24:55

The rolls in the above link are interesting but so was the adaptation of a sander to vibrate the cement! The steel ring made with the rolls is for part of a furnace that is filled with refractory cement and a bar was bolted to a hand held sander and used to make sure the cement was evenly distributed. I looked at the video just to see the rolls but found my self watching the whole thing.

John

Mark

Are you sure you need a replacement motor?

For example, are the brushes worn and are you sure the supply is getting to the motor OK?

You may save a lot of money if it is not the motor. I am sure help is at hand on this forum to carry out some checks if you need it. However, if you do need a replacement Neil's advice is good.

Regards

John

Ian Philips

The problem is that it appears that belts are measured in three different ways, inside circumference, datum circumference or outside circumference. For example in my case, I had two belts that were marked as size 37 but they were different sizes so I presume each is being measured to a different standard.

Ian Parkin is lucky in that he has a local supplier and his approach is a totally practical and sensible one.

Thanks everybody.

I took the practical advice and sacrificed the new belt that was too big and confirmed that I needed a belt just 1 inch smaller. So I need a z 36 instead of a z 37. The theory still doesn't add up though. (BTW I meant circumference, not diameter in my original post). Pleased I am not alone in experiencing problems with this and will try to make sense of it for the future.

Regards

John

I want to replace the v belt on my drill press. The old one is showing signs of wear and I suspect it has stretched because the tension adjustment is towards one end.

The old belt is marked M37. It appears that the M section has been replaced with Z so I ordered a Z37 belt only to find it is too long. (X section is OK)

Having checked the internet, I am now totally confused on how to determine which belt I need. Calculators I have found show measuring the two pulleys and the centre distance but don't say what part of the pulley to measure.

Specifications talk about Li (inside diameter). Some say measure in metric, take 22mm from the outside diameter and then convert to inches which I think gives the datum diameter and others say just measure the outside diameter.

As I can't use my original belt as a standard, can any one please tell me how to measure the belt length and convert this into the right belt number

Thanks

John (boy 25)

I am familiar with 110v supplies and connectors but I was interested to know what Paul was using so we can help him. From what he has said it sounds unlikely he has access to an industrial standard 110v supply so I asked the question to identify if his power source was suitable.

Paul

if you can post some photographs and more details I'm sure someone will come up with a definitive answer for you.

Paul

What is the source of your 110v And what exactly do you mean by a 110v plug?

I would put my money on it being 110v if the label looks original. The capacitor marking may be confusing, is it rated at 240v or for use on 240v ac? If it is rated at 240v it is not suitable for use on 240v ac if it is for use on 240v ac its actual rating will be much higher.

If it is 110v and you use it on 240v expect a Big Bang or at least some blue smoke sooner or later.

regards

The clue is in the directive number!

Neil - Shame on you for advertising a commercial product.

Hello

I am going to the Hay on Wye area for a couple of days soon.

Does any one have any suggestions about which book shops to browse for engineering subjects?

Thanks

So far:

It's good practice to use a ferrul when terminating a wire in a terminal. Agreed

Its ok to crimp with wire cutters! I don't think so. I hope Martin does't work in the aircraft, automotive or medical industry for example.

Contradictory advice re soldering the ends of wires - it sounds good but the reason not to do it given by Muzzer is sound advice. Also there is increased risk of a fracture where the non soldered/soldered point meets.

There's a lot I don't know about crimping but I do know that the crimp and the wire must match and the only tool to use is one of the ratchet types designed for the crimp in use. Otherwise it's a disaster.

A grey area for me is use of crimps on solid wires and the voltage ratings of crimps. Can any one give some sound authorative advice on the subject of crimping please.

Still off topic but seeing Michaels post, I did a search and found these floating tapping collets.

John

Yes please but hope these are additional pages and not instead of other content.

Perhaps it was a plastic dip you have seen. The link shows a DIY solution from Frost Automotive Restoration.

**LINK**

Or, depending on your application, you could make end caps from Sugru and cover the length with heatshrink?

Edited By John Shepherd on 23/11/2014 07:13:19

I wear Varifocals and get on well with them most of the time but there can be problems when I have to look at something from an awkward position or in a confined space with my head on one side for example.

I have wondered if a pair of these adjustable specs would be good for workshop use http://www.eyejusters.com/home/

Has anybody tried them?

Edited By John Shepherd on 04/10/2014 15:13:42

Neil

Whatever next - an editor who listens to his readers!

My understanding of editors is that:

They don't listen, after all they are always right.
They bully staff, the readers and the public to get results
They never let the truth get in the way of a good story
They do not respect the law, are no stranger to the courts and are surrounded by criminals
They promote sensationalism and stifle progress
They are exceptionally well paid.
etc

How on earth do you qualify for an editors job?

Seriously keep up the good work, with respect to previous editors who provided some good foundations, I think the forum and MEW is going forward in the right direction .

John Lewis have good prices on Philips lamps, also much cheaper than the own brand Diall from B&Q the last time I looked.

Please don't use a lead acid battery charger. The voltage is not smoothed and additionally can go well above the 12 volts needed if not connected to a battery.

As Jason says first check the jaws are in the right order.

Then:

1. Check the test bar, it is unlikely that a piece of MS bar is round or straight. If you have any ground bar or silver steel that will be a better bet.

2. With a decent test bar check for run out near to the jaws.

3 . You say the outside diameter of the chuck and it's backplate are true also check the face of both backplate and chuck.

4. Make sure the backplate is clean and the mating recess in the chuck is clean and free from burrs and that they are the same size.

5. What was on the lathe before, did that run true?

6. Turn a short length of bar and measure the diameter at both ends and check they are both the same.

Hope that helps to decide what is wrong

1. An engineer is someone who washes his hands before going to the toilet.

2. From an engineering company who supplied equipment to the police service: 'We can copper plate it but we can't copper proof it'.

3. A good machinist is someone who knows how a part will turn out before they start. (I wish).

To put things in perspective - there is is nothing much wrong with LEDs. They have come along way from being (red) low level indicators to now providing satisfactory levels of illumination with a spectrum that suits many applications, use less power and run relatively cool.

I do agree though that the way they are powered can be an issue. When 240v LED lamps first became available, I seem to remember that the interference from from the in built power supply in some of them wiped out DAB radio reception in the home. Now, in my office I have a reading lamp with an LED lamp close to a DAB radio and there is no problem. If one buys lamps from established reputable manufacturers that have a history of supplying the UK, one would hope that the safety issues highlighted (that are a serious concern) are not present.

If we are considering low voltage (12v) LED arrays, then we have a choice when selecting a suitable and safe power source that is up to the job. The problem of interference and safety becomes more of an issue when we try to do things 'on the cheap'. I know it is sometimes difficult and for instance I would not have a 'wall wart' plug in power supply in the house if I had a choice. My main aversion to the older ones is that the weight tends to cause them to not stay secure in a wall socket, the newer lightweight switch mode types overcome this but can cause interference, suffer poor reliability and I believe carry a higher fire risk if they fail.

It is doubtful if we can have much influence on preventing people from buying rubbish but if we do it right, there is no reason not to take advantage of LEDs in the home and in the workshop when there use is appropriate.

John