Member postings for John Rudd

Either the lever is not engaging the half nut  ( not adjusted correctly ) or the half nut is worn

Edited By John Rudd on 13/01/2021 11:17:31

https://www.arceurotrade.co.uk/Catalogue/Machine-Spares/C4A-Bench-Lathe-Spares/C4A-210-Timing-Belt-1512415

https://www.arceurotrade.co.uk/Catalogue/Machine-Spares/C6-Bench-Lathe-Spares/C6-944-Timing-Belt-For-6-Speed-C6

Edited By John Rudd on 07/01/2021 18:38:26

Edited By JasonB on 07/01/2021 18:50:54

Brian, I sent you a private message....see top of page for flashing envelope...

If you can measure the belt width and length.....? Any idea of the tooth count?

The 9 x 20 lathe has a 170xLO50 belt that looks similar has 85 teeth and is available from:

https://www.bearingstation.co.uk/products/xl-section-02-pitch-timing-belt-05-wide-17-long=43213

I checked an online manual for the db8 ( Chesters website) but it doesnt give the size in the parts listing...

so over to a user on here perhaps...?

Screwed on.....
I currently have one disassembled...

That is how I know.

Edited By John Rudd on 04/01/2021 15:11:15

I have a steady for a C3 style lathe for sale in the FS section......( not sure which flavour of mini lathe...) if interested....( same centre height as an ML7 .....or not far off...)

Well done Clive, you lucky bu**er...😂😂👍

Edited By John Rudd on 15/12/2020 16:24:57

Not power transistors....

This board uses 2 scr's and 2 diodes in a fw bridge configuration....

The diode is 1000v piv rated at 6Amps....try Ebay....

Gavlar, there should be a slot in the quill to accept a 'drill drift' for removing tapered items.....

Else a long rod of appropriate diameter inserted from the top, smartly struck with a deadblow hammer ought to remove it....but the drill drift is the preferred option.

Damon, looks like the belt is failing due to being too tight and being "encouraged to roll over the pulley's edges"

If I recall, the earlier 9xx series were fitted with a 710 belt, later models of the Chester flavour had a 730.

I think of all the belt issues reported on here, most are about the shorter 710 belt....

Probably the reason why my Chester has never had a belt fail...

Hope you get sorted..

Edited By John Rudd on 22/10/2020 15:18:17

Damon,

I have a Chester 9 x 20 lathe, very similar in design/looks to the 918. I've not had to replace the belt on mine in the years it has been in service....( 10 plus....)

I added a three phase motor /inverter to mine and binned the single phase one.( stayed with the 3/4hp size, but had to machine the motor's shaft to fit the pulley)

As to your belt issue, how is the belt breaking? Is it fraying or snapping?

Some checks to make:

1) Check the pulley alignment, unlikely to be the issue but rule it out.

2) Check the pulleys for any damage to the V grooves, scoring,pitting,burrs etc.

2) Belt tension....is it too tight? With the tensioning lever in the 'run' position, the tension on the belt should be about 1/2" deflection on the longest run....( this is an arbitrary figure....'wet finger in the air' kinda measurement for the purists!)

3) It might pay to go for a longer belt if the tension is too tight.

I got my spares from Beeline Engineering in Milton Keynes cost a lot less than £16!

Edited By John Rudd on 22/10/2020 12:43:55

While I do not profess to be an expert in repairing the electronics for mini mills/lathes and larger DC motored machines, I am comfortable with the experience and knowledge I have in expediting repairs...

Even though the replacement board is new, until the wiring/switches etc test out ok and the 'overload lamp' issue is resolved, the board test at the moment will not work.....

Edited By John Rudd on 19/10/2020 14:58:55

David,

The switches need checking with a dvm on its Ohms ranges or with a continuity tester....( battery bulb and bits of wire should suffice....)

Manchester is a bit far for me...(Newcastle...) otherwise I'd look at it for you...

Test the switches then come back and we'll go from there..

David,

A bit more info please....

What model speed controller is it? For a CL250 its likely to be an FC250, can you confirm model number plz.

How was the motor tested? Ideally it should be bench tested on a DC power supply and run up to its max speed. Any arcing/sparking at the commutator needs to be checked.....Shorted comm segments/worn brushes etc...

Has the speed pot switch been tested? The contacts on the rear should close at minimum speed ( turned fully anti clockwise to off )  and be open at any other pot setting.

Edited By John Rudd on 18/10/2020 17:11:05

Yup you are right, dunno what I was thinking...🤔

Obviously not paying attention at the back....

I'm no metallurgist,

Is it possible that at the elevated temps we are talking that the qualities of the hss are impaired to the point of forming micro crystals if cooled by cold water immersion?

Surely, 50-60 degrees isnt hot enough to be effective but enough to cause discomfort?

My turn to help....

From my Stuart 10V drawings, assuming the ports are centrally displaced;

the outer edges of the ports are 7/16" apart, the inner port edges are 9/32" apart. The central port is 1/8" wide centrally displaced. I make the outer port width to be 5/64".

all ports 9/32" high

HTH..

ah. Jason beat me...my maths is a bit too slow...😂

Edited By John Rudd on 14/10/2020 14:24:53

Edited By John Rudd on 14/10/2020 14:26:17

I'll offer up my experiences with various energy suppliers and sm's

Prior to moving house 3 yrs ago, we were staunch BG customers( well I did work for them for over 30 yrs..) had smart meters fitted and had no issues...,

To 2017, moved house to a brand new estate, all properties were supplied by E-On and had smart meters fitted.

We stayed with E-On until we were acosted approached by Scottish Power in the Metro Centre one day.....They assured us lower bills...Ok, sign me up....So we left E-On for SP.....

Some time later, SP asked if we wanted a smart meter for each utility, told them they were already installed 'Oh, we cant read them' came the reply..

After being with SP for the year, conscious of the need to look for cheap deals, we returned to E-On as provider.

Sad thing is, although their meters are installed here, we still have to return readings to them on a quarterley basis..

So somewhere along the way, the system has fallen over....not working as it should..E-On's customer database isnt that clever to recognise a returning customer with smart meters already at the address.....

Thanks for the replies everyone,

So are we gashing the clearance free hand or using some jig/toolholder while doing this?

I'm thinking that anything sized under say 8mm is going to be a challenge?