Member postings for Alan Donovan

Hello.

First.

To follow on from JasonB’s comments on the dimensioning of Myford parts. Myford (Beeston) used a ‘metal off’ system of tolerancing for all their manufactured parts. This was to enable the engineer actually cutting the metal to have a target dimension to achieve, but if he/she went over that dimension they would almost certainly still be within tolerance.
It also removed the need for the operative to undertake the mental mathematics needed with the plus and minus tolerancing systems, where maths errors can lead to potentially higher scrapage rates for components.

As we all understand, it is easier to remove excess metal than replace what we removed in error.

Second.

If I remember correctly, I think there was reference in this thread to wax(?) printing components to investment cast in metal. Would this require two CAD files? The second file to print an enlarged wax component to allow for casting shrinkage.  Plus the additional metal (wax) for where machining is required.

All the best to everyone. Alan

Edited By Alan Donovan on 18/09/2023 07:44:49

Very slightly ‘off topic’…….

My ‘pet hate’ is those motorists who push down the clutch, push into gear, turn the ignition key and as soon as the engine ‘fires’ release the clutch to immediately drive off. I have witnessed this many times and this MUST shorten engine life very significantly.

I am certainly not convinced the residual oil on the moving parts is good enough to lubricate, especially on a cold start up. Is modern life that busy that we cannot allow a mere 5 second pause between an engine start and driving off to allow the oil to get to pressure and lubricate under minimum load?

That’s it ……. rant over!

Alan.

Edited By Alan Donovan on 14/07/2023 07:50:08

Hi.

I have NHS hearing aids. On a recent visit my ‘major high street’ optician, who is also very proactive in encouraging clients to have their hearing checked by them, I noticed that all the advertisements for hearing aids were the same brand as my NHS supplied ones.

A.

Hi Tim.

I had the same issue with the nose bearing on my lathe motor, fitted to a Myford. I tried to find an ‘off the shelf’ replacement but was unable to find one. I then took it to my local rewind specialist who then refused to do the job. He doesn’t repair motors with plain bearings.

I was fortunate in that I had access to another lathe, so ended up making one out of phosphor bronze, this included a shallow groove in the bore to aid lubrication.  I bought a suitable reamer to finish the bore, which was a good decision as I had to ream again on assembly as the bore had closed down (as anticipated). That was more than a year ago - so far so good.

Strangely the ‘old’ bearing had an imperial OD and a metric ID (I think it was that way round, memory not as good as it was), so my assumption is that the motor was manufactured at the time when UK industry was transitioning from imperial to metric.

It’s worth a go if you can get access to another lathe.

Alan.

Edited By Alan Donovan on 30/06/2023 08:14:02

Hi Jon.

There was a ‘9’ series machine. It was the MG9. The prefix being MG for Myford Grinder. There was a significant redesign of the grinder in later years and this became the MG12. The ‘10’ series machine you know. I am not aware of an ‘11’ series machine being developed ……. unless this reference was assigned to the ‘MiniKop’ copying lathe, Maybe someone else on the forum may be able to throw some light on this.

Alan.

Edited By Alan Donovan on 30/05/2023 20:19:33

I replaced mine with a piece of leather from an old jacket. The leather was part of my ‘that will come in handy one day’ collection of bits and pieces.

I found it easy to fit and more flexible than the original rubber.

Alan.

+1 for Oldiron.

If you choose to ask for a refund, ebay have a complaints/dispute procedure you can use.  Details of how to proceed are on their website.

Edited By Alan Donovan on 28/03/2023 06:58:57

Edited By Alan Donovan on 28/03/2023 07:04:49

Edited By Alan Donovan on 28/03/2023 07:24:18

Hi Chris.

Your collet chuck problem has been bugging me, so I am back with another possibility (maybe ? ?).

You say the internal sleeve, that holds the collet (red in your diagram) ..... is a very firm push fit in the body. Is it possible that the internal sleeve has a couple on 'bruises' on the OD that is causing this tightness. I feel this should be very close fitting but a 'free sliding fit' in the main body. If there is slight bruise present causing tightness, this may be a contributory factor.

Secondly, is there a circlip groove, in the bore at the nose end of the main body (green). If 'yes', then it may be a circlip has been lost / ommited. This circlip limits the forward movement of the internal sleeve and may make it possible to adjust the clamp / open setting of the collet correctly. If you look at the arrangement drawing of the Myford Collet assembly - as provided by Swarf, Mostly - there is a circlip fitted in this area to limit the movement of the internal sleeve.

That's it. Alan.

Hello David.

I had a similar unexplained noise from my Myford develop a few days after having the motor refurbished. A rythmic knocking sound.

It turned out that the pully on the motor shaft hadn't been secured properly. So my first suggestion would be to look at that. Maybe check all the pulleys in that area as it has been modified.

A second suggestion would to look at the 'back gear' area inside the headstock. The back gear is locked and unlocked via a small cam with lever. If the lever has not been pushed right 'home' it can sometimes just catch on the internals of the headstock casting.

Hope that helps. Alan.

Hello All.

Many thanks to all who responded to my query.

I now understand what this plate is telling me and have a bit more knowledge about electric motors and their differences and workings, so my query is answered. Many thanks again.

Alan

Hello all.

I am considering purchasing a machine that has the following motor plate.

My electrical knowledge is very limited hence the question.

My interpretation of the motor plate is that it shows details for both 3 phase and 1 phase operation and how it should be ‘wired up’ to achieve that. I assume that is what the 3 legged star and delta signs convey. The seller tells me it is 3 phase.

Am I correct in thinking that I can convert this motor to 1 phase operation by just rewireing the motor to cable connection appropriately. All my domestic electrics are 1phase.

Many thanks in advance for any responses.

Alan.

Hi. Chris.

My request for a photo only needed to be an outside view, but your sectional view gives me the information that I need.

I still feel that you are over tightening the closer. If the closer (yellow) is over tightened it pushes the collet (grey) further in to the collet housing (red) thus closing down the collet. Try slakening off the closer (say one eight of a turn at a time) and then closing, and then opening, the collet with the handle mechanism.

I feel fairly confident you will come to a position where you can open and close the collet to load and unload your component without having to further adjust (unscrew) the closer to release the component. The handle mechanism will / should take up the additional slack in the collet and should still provide the necessary force to grip the component for machining.

I hope this helps. Please let us know if this solves the problem.

Best regards. Alan.

Hi.

After re-reading your enquiry, and studying the ML7 / S7 collet attachement drawing, my first thought is that you should not be loosening the closer to release the part from the collet. Are you sure you are not tightening the closer too much in the first place?

I still think it makes sense to load a couple of pictures onto this enquiry so the forum members can see what the equipment looks like!

All the best Alan.

+1 for ebay.

Hello.

I am used to the Myford lever operated collet chuck for the ML7 & S7 lathes.  Old Mart’s description of how the chuck is used / operated matches my experience for successful loading and unloading of turned parts.

My experience of the 254 and its accessories is very limited, so I am not aware if Myford (Beeston) made their own collet chuck, or this was provided by another company. The name Pfander is not familiar to me. May I suggest a couple of pictures of the unit. This may initiate a response from someone with more knowledge.

best regards. Alan

Edited By Alan Donovan on 31/10/2022 19:55:18

Hi Graham.

‘Primary gear’ is not terminology we are used to with the ML10.

I recommend you take a photo or two of the gear and area in question, and post them in this thread, I am confident you have the answers you need within the hour.

Just be aware that to post photos, you have to place them in an album first to be able to then copy them into the thread.

lastly, welcome to the forum.

Best regards. Alan

Edited By Alan Donovan on 10/07/2022 07:21:13

Hi all.

I believe I have a faulty Neutral switch on a Yamaha FZ 750. Replacement part plus new seal are now ready to be fitted, but its location on the bike is not obvious.

Close inspection of the bike and scouring thought the parts manual, I have come to the conclusion that it is located behind the drive sprocket cover. This cover also supports the hydraulic piston for the clutch (this appears to push on the end of a long rod that actuates the clutch) and also the gear change shaft passes through this cover.

I intend (hope) to remove the sprocket cover with the clutch piston assembly still attached ....... it seems possible. Before I go 'blundering on' I thought I would ask for a 'sanity check' and ask if there is anything I should be aware of, or take particular care about.

Please find below parts diagram for neutral switch (item 6) and a photo of the cover I intend to remove.

Many thanks in advance to all who respond.

Best regards. Alan.

Hi All.

Well it has been a long time coming, but further to my original posting, I have had some success altering/reducing the noise emitted by the SL 125 silencer.

I tried a plain extension tube - no good. No room to put in a perforated baffle as per my original post - so no good

I then found a piece of copper pipe that was a 'snug fit' inside the outer pipe of the silencer outlet, if that makes sense. See sectional sketch of muffler outlet - above - for details.

I managed to make and insert three baffles into the copper pipe and the whole assembly was lightly hammered into the tailpipe. I had intended to put some wire wool into the inlet side of the muffler - but decided against that - it just didn't seem right in this case. The exhaust sound is now quieter and the harshness of the note has gone, so I am happy.

So this is what I ended with ..........

Copper tube hammered into place. The visible extension is about 2.5 inches long - 3.25 inches overall length.

View on end of extension pipe, with baffles inside.

I hope the final result is of interest to you.

Thanks again to everyone for their input - I am pleased with the result.

All the best.

Alan.

Edited By Alan Donovan on 12/06/2022 21:11:35

Edited By Alan Donovan on 12/06/2022 21:12:07

Edited By Alan Donovan on 12/06/2022 21:14:19

Hello John

Many thanks for your reply. This is very much appreciated.

All the best. Alan.

Hello all.

I have been given some unmachined Cast Locomotive Wheels, and I am trying to identify which locomotive - or Locomotives these are from.

There are three differing sizes, the larger two wheels are intended as 'drivers'. The smaller wheel is a bogie wheel.

Here are the technical details followed by photos of the wheels. All dimensions are in mm and are 'as cast'.

Largest wheel - 43.2 tread diameter, 16 spoke, 6 off. Marked (stamped) 220.

Medium wheel - 36.1 tread diameter, 14 spoke, 12 off. Marked (cast) X222.

Small wheel - 23.2 tread diameter, 10 spoke, 4 off. No markings.

I have searched the website of a couple of wheel 'casters/suppliers' but have been unsuccessful in matching the reference numbers with their current offerings.

Any help would be greatly appreciated. Best wishes to all.

Alan.