I had a mishap this week when the main terminal on a tractor starter
motor became loose and rotated allowing it to contact the motor winding
terminal, while the engine was running. I didn't notice anything until
the damage was done.

As this is an old ford industrial engine the starter is going to take a
while to arrive so I thought I'd see if the old one could be made
functional again.

The armature seems okay, no shorts to the iron core and the commutator
and brushes are serviceable.

One of the 4 stator coils has shorted and burned off its wrappings, the
others seem fine, the copper is so large a cross section it is not
possible to discriminate the resistance as it is so low but the copper
rectangular section looks sound.

Now looking on you tube if anyone has the time to watch some old school
workmanship:

https://www.youtube.com/watch?v=4bFou5VIFzM

at 2 minutes the guy is cutting some insulation sheet, anyone any idea
what it is and if it is avalable?

Later at 4:20 he wraps with a tape, any ideas what it is and where I can
get some?

At 5:40 a paint is used to cover the wrapped coil, is this likely to be
anything special?

On 01/05/2021 07:13 pm, AJH wrote:

I had a mishap this week whenÂ* the main terminal on a tractor starter
motor became loose and rotated allowing it to contact the motor winding
terminal, while the engine was running. IÂ* didn't notice anything until
the damage was done.

As this is an old ford industrial engine the starter is going to take a
while to arrive so I thought I'd see if the old one could be made
functional again.

The armature seems okay, no shorts to the iron core and the commutator
and brushes are serviceable.

One of the 4 stator coils has shorted and burned off its wrappings, the
others seem fine, the copper is so large a cross sectionÂ* it is not
possible to discriminate the resistance as it is so low but the copper
rectangular section looks sound.

Now looking on you tube if anyone has the time to watch some old school
workmanship:

https://www.youtube.com/watch?v=4bFou5VIFzM

at 2 minutes the guy is cutting some insulation sheet, anyone any idea
what it is and if it is avalable?

Not seen that before (unless, as suggested by another poster, it's PVC).

We used to use Kraft sp? for layered insulation.

For example:

https://www.rajapack.co.uk/protective-packaging/paper-packaging/crepe-kraft-paper-75mmx15m-pack-of-24_skuPCKP.html?priceVAT=true&cq_src=google_ads&cq _cmp=9232197084&cq_con=101859384198&cq_term=&cq_me d=pla&cq_plac=&cq_net=g&cq_pos=&cq_plt=gp&gclid=Cj 0KCQjw-LOEBhDCARIsABrC0TnlShh9oXdT4adQ_Ihtm8l-vm_ppIwztVnvGjqlErZd6V8HO5miMXAaAvOTEALw_wcB&gclsr c=aw.ds

Later at 4:20 he wraps with a tape, any ideas what it is and where I can
get some?

That looks like a woven insulation tape, a bit like this:

https://www.mbfg.co.uk/QL5028.html?gclid=Cj0KCQjw-LOEBhDCARIsABrC0Tkl_UzPAE46ZSVhMtNtyKUOFIEgNg2Mr1x wsk1EiMzvJUwq9QK_H5QaAvOAEALw_wcB

[But completely wrapping stator coils was not common in the armature
winding world.]

At 5:40 a paint is used to cover the wrapped coil, is this likely to be
anything special?

I can see the bright colour, but suggest that that is a varnish rather
than a paint. The purpose (maybe among others) will be to hold the coil
turns firmly and prevent abrasion of the wire's own insulation by
reducing vibration "chatter".

On 01/05/2021 19:13, AJH wrote:
I had a mishap this week whenÂ* the main terminal on a tractor starter
motor became loose and rotated allowing it to contact the motor winding
terminal, while the engine was running. IÂ* didn't notice anything until
the damage was done.

As this is an old ford industrial engine the starter is going to take a
while to arrive so I thought I'd see if the old one could be made
functional again.

The armature seems okay, no shorts to the iron core and the commutator
and brushes are serviceable.

One of the 4 stator coils has shorted and burned off its wrappings, the
others seem fine, the copper is so large a cross sectionÂ* it is not
possible to discriminate the resistance as it is so low but the copper
rectangular section looks sound.

Now looking on you tube if anyone has the time to watch some old school
workmanship:

https://www.youtube.com/watch?v=4bFou5VIFzM

at 2 minutes the guy is cutting some insulation sheet, anyone any idea
what it is and if it is avalable?

'insulation sheet'; on old kit would be something like phenolic resin
impregnated paper - a sort of bakelite lookalike - but that looks
alarmingly like simple plastic sheet. Which will melt at high temperatures.

You can buy stuff like that at any model shop.
Oh thinking, I'd use ptfe.

https://www.ebay.co.uk/itm/223216541194

Later at 4:20 he wraps with a tape, any ideas what it is and where I can
get some?

Almost anything would do. Back in the day it might have been cotton or
linen.

I wouldn't use nylon - cotton 'webbing tape' is probably best these days.

https://www.ebay.co.uk/itm/191918411510


At 5:40 a paint is used to cover the wrapped coil, is this likely to be
anything special?


Typically old electric wire was insulated with shellac. French polish to
you.

That looks like 'any old muck'. Its only there to stabilise the tape.

For the authentic Awful Smell on overload, why not use shellac?




--
"Socialist governments traditionally do make a financial mess. They
always run out of other people's money. It's quite a characteristic of them"

Margaret Thatcher

On 02/05/2021 09:16, The Natural Philosopher wrote:

You can buy stuff like that at any model shop.
Oh thinking, I'd use ptfe.

https://www.ebay.co.uk/itm/223216541194

Thanks I wonder how that differs from the oven liner.

I wouldn't use nylon - cotton 'webbing tape' is probably best these days.

https://www.ebay.co.uk/itm/191918411510


Yes looks about right

For the authentic Awful Smell on overload, why not use shellac?
I wondered what that smell was.

Well some coil rewiinders tend to pot the winding if there is room to
achieve this, it often last longer than the traditional vanish approach.
Brian

--

This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"AJH" wrote in message
...
I had a mishap this week when the main terminal on a tractor starter motor
became loose and rotated allowing it to contact the motor winding terminal,
while the engine was running. I didn't notice anything until the damage
was done.

As this is an old ford industrial engine the starter is going to take a
while to arrive so I thought I'd see if the old one could be made
functional again.

The armature seems okay, no shorts to the iron core and the commutator and
brushes are serviceable.

One of the 4 stator coils has shorted and burned off its wrappings, the
others seem fine, the copper is so large a cross section it is not
possible to discriminate the resistance as it is so low but the copper
rectangular section looks sound.

Now looking on you tube if anyone has the time to watch some old school
workmanship:

https://www.youtube.com/watch?v=4bFou5VIFzM

at 2 minutes the guy is cutting some insulation sheet, anyone any idea
what it is and if it is avalable?

Later at 4:20 he wraps with a tape, any ideas what it is and where I can
get some?

At 5:40 a paint is used to cover the wrapped coil, is this likely to be
anything special?

"Brian Gaff \(Sofa\)" wrote:
Well some coil rewiinders tend to pot the winding if there is room to
achieve this, it often last longer than the traditional vanish approach.

Nice one! :-)

--
Chris Green
·

On 01/05/2021 19:13, AJH wrote:
I had a mishap this week whenÂ* the main terminal on a tractor starter
motor became loose and rotated allowing it to contact the motor winding
terminal, while the engine was running. IÂ* didn't notice anything until
the damage was done.

As this is an old ford industrial engine the starter is going to take a
while to arrive so I thought I'd see if the old one could be made
functional again.

The armature seems okay, no shorts to the iron core and the commutator
and brushes are serviceable.

One of the 4 stator coils has shorted and burned off its wrappings, the
others seem fine, the copper is so large a cross sectionÂ* it is not
possible to discriminate the resistance as it is so low but the copper
rectangular section looks sound.

Now looking on you tube if anyone has the time to watch some old school
workmanship:

https://www.youtube.com/watch?v=4bFou5VIFzM

at 2 minutes the guy is cutting some insulation sheet, anyone any idea
what it is and if it is avalable?

The sound it makes while being is the same as some very thin phenolic
resin sheet I used to have, but that was brown.

Later at 4:20 he wraps with a tape, any ideas what it is and where I can
get some?

It looks like asbestos tape and if that is being done in Pakistan, it
might be. However, there is a wide range of safer alternatives;

https://www.bevi.com/products/coil-w...s-non-adhesive

At 5:40 a paint is used to cover the wrapped coil, is this likely to be
anything special?

As others have said, that looks more like a varnish than a paint. The
same web site offers these:

https://www.bevi.com/products/coil-w...on-and-casting


--
Colin Bignell

On 02/05/2021 10:42, nightjar wrote:

It looks like asbestos tape and if that is being done in Pakistan, it
might be. However, there is a wide range of safer alternatives;

https://www.bevi.com/products/coil-w...s-non-adhesive

At 5:40 a paint is used to cover the wrapped coil, is this likely to
be anything special?

As others have said, that looks more like a varnish than a paint. The
same web site offers these:

https://www.bevi.com/products/coil-w...on-and-casting




Good find but one page says sold only in the Swedish market.

On 02/05/2021 11:19, AJH wrote:
On 02/05/2021 10:42, nightjar wrote:

It looks like asbestos tape and if that is being done in Pakistan, it
might be. However, there is a wide range of safer alternatives;

https://www.bevi.com/products/coil-w...s-non-adhesive

At 5:40 a paint is used to cover the wrapped coil, is this likely to
be anything special?

As others have said, that looks more like a varnish than a paint. The
same web site offers these:

https://www.bevi.com/products/coil-w...on-and-casting




Good find but one page says sold only in the Swedish market.

I didn't see that, but it was the first hit I got on a Google search for
motor rewinding supplies. There are plenty of motor rewinders in the UK
and they must get their supplies from somewhere.

--
Colin Bignell

On 02/05/2021 12:14, nightjar wrote:


I didn't see that, but it was the first hit I got on a Google search for
motor rewinding supplies. There are plenty of motor rewinders in the UK
and they must get their supplies from somewhere.


Thanks for taking the trouble to look. In the meanwhile I have ordered a
sheet of 0.5mm PTFE, the adhesive PTFE covered fibre glass tape and some
exhaust paint. The PTFE won't be here till June and I hope the new motor
will be fitted by then, so I will do a repair at my leisure.

On 02/05/2021 13:19, AJH wrote:
On 02/05/2021 12:14, nightjar wrote:


I didn't see that, but it was the first hit I got on a Google search
for motor rewinding supplies. There are plenty of motor rewinders in
the UK and they must get their supplies from somewhere.


Thanks for taking the trouble to look. In the meanwhile I have ordered a
sheet of 0.5mm PTFE, the adhesive PTFE covered fibre glass tape and some
exhaust paint. The PTFE won't be here till June and I hope the new motor
will be fitted by then, so I will do a repair at my leisure.

Full marks for considering a fairly out of the normal repair. That's one
job I have never done myself (although having seen from YouTube how it
is done, I realise it is not quite so daunting as it appeared when I was
a cash-strapped youth).