I've successfully managed the repairs on the Rover wheel arch liners - not
a tidy job, but strong and you can't really see it anyway.

So am thinking on modding my SIP MigMate 130 Turbo. A method of changing
the polarity for gasless wire, and improving the wire feed.

I've not even opened it up for a look yet, so these are just thoughts.

Presumably the gas/gasless models use a switch? Can't seem to find one
aftermarket anywhere, and SIP spares are expensive. So I was wondering
about using terminals and jumpers.

Looking for large insulated posts for panel mounting has drawn a blank so
far - something like a larger version of a panel mounting loudspeaker
terminal is what I want, but in 10mm or so, and with insulated nuts.

As regards the wire drive motor I was thinking along the lines of
converting it to PWM drive. Assuming it's not already.

--
*Work like you don't need the money. Love like you've never been hurt.

Dave Plowman London SW
To e-mail, change noise into sound.

On 10 Aug, 10:06, "Dave Plowman (News)" wrote:

As regards the wire drive motor I was thinking along the lines of
converting it to PWM drive. Assuming it's not already.

If it's anything like SIPs I've previous done battle with, it's not
the motor that's the problem, it's the roller drive's inability to
grip the wire.

In article
,
Andy Dingley wrote:
On 10 Aug, 10:06, "Dave Plowman (News)" wrote:

As regards the wire drive motor I was thinking along the lines of
converting it to PWM drive. Assuming it's not already.

If it's anything like SIPs I've previous done battle with, it's not
the motor that's the problem, it's the roller drive's inability to
grip the wire.

That bit seems ok on mine - you can adjust the friction between the drive
wheel and wire. But the actual speed varies dramatically at the slow end
which is where it's critical for me. You can here the motor speed changing
on its own.

--
*Growing old is inevitable, growing up is optional

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Dave Plowman (News) wrote:
That bit seems ok on mine - you can adjust the friction between the
drive wheel and wire. But the actual speed varies dramatically at the
slow end which is where it's critical for me. You can here the motor
^^^^
speed changing on its own.

--
*The average person falls asleep in seven minutes *

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" wrote in message
...
I've successfully managed the repairs on the Rover wheel arch
liners - not
a tidy job, but strong and you can't really see it anyway.

So am thinking on modding my SIP MigMate 130 Turbo. A method of
changing
the polarity for gasless wire, and improving the wire feed.

I've not even opened it up for a look yet, so these are just
thoughts.

Presumably the gas/gasless models use a switch? Can't seem to find
one
aftermarket anywhere, and SIP spares are expensive. So I was
wondering
about using terminals and jumpers.

Looking for large insulated posts for panel mounting has drawn a
blank so
far - something like a larger version of a panel mounting
loudspeaker
terminal is what I want, but in 10mm or so, and with insulated nuts.

As regards the wire drive motor I was thinking along the lines of
converting it to PWM drive. Assuming it's not already.

--
*Work like you don't need the money. Love like you've never been
hurt.

Dave Plowman London SW
To e-mail, change noise into sound.

Dave,

Ask on www.mig-welding.co.uk the forum there will have someone who
has already done it !

AWEM

On Tue, 10 Aug 2010 10:06:30 +0100, Dave Plowman (News) wrote:
Looking for large insulated posts for panel mounting has drawn a blank
so far - something like a larger version of a panel mounting loudspeaker
terminal is what I want, but in 10mm or so, and with insulated nuts.

Hmm, give Matty F from here a prod - he was making his own insulators for
tram work and doing a really good job. You could maybe make your own to
take a regular bolt to use as a terminal and provide the insulation
barrier between the bolt and surrounding metalwork. Drill a hole through
the bolt to take the wire.

For the nuts, perhaps there's some form of plastic you could heat and dip
them in to cover them (then just lightly drill either side and remove the
plastic from the threaded section once it's set) - or cast something to
take the nut using the same insulating material as for the bolts.

(why do the nuts need to be insulated? If they're securing thick wire,
I'd be concerned that you couldn't get them tight enough by hand - would
a regular old nut, tightened by a spanner, and with a flip-up insulated
cover not do? Tie a bit of rope to the spanner and hang it on the machine
so it's always nearby)

cheers

Jules

Andrew Mawson wrote:

"Dave Plowman (News)" wrote in message

As regards the wire drive motor I was thinking along the lines of
converting it to PWM drive. Assuming it's not already.


Ask on www.mig-welding.co.uk the forum there will have someone who
has already done it !

AWEM

Some time ago someone on that forum completely redesigned the speed control
for that welder using a separate*24v ? transformer*and circuitry.
Unfortunately its such a busy forum, i now cant find any reference to his web
page which had all the construction details.
\0

In article ,
Andrew Mawson wrote:
Ask on www.mig-welding.co.uk the forum there will have someone who
has already done it !

I did do a Google, but found some dreadful bodges. Since those were the
first hits, decided I'd probably better going my own route.

--
*Am I ambivalent? Well, yes and no.

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Jules Richardson wrote:
On Tue, 10 Aug 2010 10:06:30 +0100, Dave Plowman (News) wrote:
Looking for large insulated posts for panel mounting has drawn a blank
so far - something like a larger version of a panel mounting
loudspeaker terminal is what I want, but in 10mm or so, and with
insulated nuts.

Hmm, give Matty F from here a prod - he was making his own insulators
for tram work and doing a really good job. You could maybe make your
own to take a regular bolt to use as a terminal and provide the
insulation barrier between the bolt and surrounding metalwork. Drill a
hole through the bolt to take the wire.

One of my cars has exactly what I need - it brings the battery cable
through the bulkhead. Sadly. it's an old car and I can't find that bit as
a spare. But it seems to me it would be a common stock part - if only i
knew where. Couldn't find it at RS or any of the car wiring specialists.

For the nuts, perhaps there's some form of plastic you could heat and
dip them in to cover them (then just lightly drill either side and
remove the plastic from the threaded section once it's set) - or cast
something to take the nut using the same insulating material as for the
bolts.

(why do the nuts need to be insulated? If they're securing thick wire,
I'd be concerned that you couldn't get them tight enough by hand - would
a regular old nut, tightened by a spanner, and with a flip-up insulated
cover not do? Tie a bit of rope to the spanner and hang it on the
machine so it's always nearby)

I was hoping for something which didn't need a tool to use. I have a
disconnect device on the car battery which is simply a thumb wheel and
that handles the same sort of current.

cheers

Jules

--
*Depression is merely anger without enthusiasm *

Dave Plowman London SW
To e-mail, change noise into sound.

In message , "Dave Plowman (News)"
writes
In article ,
Jules Richardson wrote:
On Tue, 10 Aug 2010 10:06:30 +0100, Dave Plowman (News) wrote:
Looking for large insulated posts for panel mounting has drawn a blank
so far - something like a larger version of a panel mounting
loudspeaker terminal is what I want, but in 10mm or so, and with
insulated nuts.

Hmm, give Matty F from here a prod - he was making his own insulators
for tram work and doing a really good job. You could maybe make your
own to take a regular bolt to use as a terminal and provide the
insulation barrier between the bolt and surrounding metalwork. Drill a
hole through the bolt to take the wire.

One of my cars has exactly what I need - it brings the battery cable
through the bulkhead. Sadly. it's an old car and I can't find that bit as
a spare. But it seems to me it would be a common stock part - if only i
knew where. Couldn't find it at RS or any of the car wiring specialists.

Marine supplies?
Similar to these?

http://www.sailsmarine.com/ItemDetail.aspx?c=2246

http://homehealthsuperstore.com/Blue...-Feed/M/B000Y8
7SEE.htm



--
Bill

In article ,
Bill wrote:
One of my cars has exactly what I need - it brings the battery cable
through the bulkhead. Sadly. it's an old car and I can't find that bit
as a spare. But it seems to me it would be a common stock part - if
only i knew where. Couldn't find it at RS or any of the car wiring
specialists.

Marine supplies? Similar to these?

http://www.sailsmarine.com/ItemDetail.aspx?c=2246

http://homehealthsuperstore.com/Blue-Sea-2204-Red-Terminal-Feed/M/B000Y87SEE.htm

That sort of thing, but it would be easier to make up something similar
than import from the US. ;-)

--
*On the other hand, you have different fingers*

Dave Plowman London SW
To e-mail, change noise into sound.

On 11 Aug, 10:07, "Dave Plowman (News)" wrote:
In article ,
Bill wrote:

One of my cars has exactly what I need - it brings the battery cable
through the bulkhead. Sadly. it's an old car and I can't find that bit
as a spare. But it seems to me it would be a common stock part - if
only i knew where. Couldn't find it at RS or any of the car wiring
specialists.
Marine supplies? Similar to these?
http://www.sailsmarine.com/ItemDetail.aspx?c=2246

http://homehealthsuperstore.com/Blue-Sea-2204-Red-Terminal-Feed/M/B00...

That sort of thing, but it would be easier to make up something similar
than import from the US. ;-)

--
*On the other hand, you have different fingers*

Dave Plowman London SW
To e-mail, change noise into sound.

my old mission speakers have chunky screw terminals on them - wire
goes though the boly bit and secured by plastic coated nut....in red
and black too ;)

Jim K

In article
,
Andy Dingley wrote:
As regards the wire drive motor I was thinking along the lines of
converting it to PWM drive. Assuming it's not already.

If it's anything like SIPs I've previous done battle with, it's not
the motor that's the problem, it's the roller drive's inability to
grip the wire.

Drawn out the circuit, and it's crude in the extreme. It basically uses
the same volts as the welding side to drive the motor via a simple one
transistor controller, with no regulation. So unless the welding part is
drawing constant current, the drive to the motor will vary with that.
So I'm going to drive it off its own PSU. A quick test shows that PWM
drive increases the torque at low revs dramatically.

--
*A nest isn't empty until all their stuff is out of the attic

Dave Plowman London SW
To e-mail, change noise into sound.

On Aug 10, 10:28 am, "Dave Plowman (News)"
wrote:
In article
,
Andy Dingley wrote:

On 10 Aug, 10:06, "Dave Plowman (News)" wrote:
As regards the wire drive motor I was thinking along the lines of
converting it to PWM drive. Assuming it's not already.
If it's anything like SIPs I've previous done battle with, it's not
the motor that's the problem, it's the roller drive's inability to
grip the wire.

That bit seems ok on mine - you can adjust the friction between the drive
wheel and wire. But the actual speed varies dramatically at the slow end
which is where it's critical for me. You can here the motor speed changing
on its own.

when my sh1tty draper mig's wire feed slipped (sh1t rollers too) the
motor sound/pitch would change too....

Jim K

On 10 Aug, 10:28, "Dave Plowman (News)" wrote:

You can here the motor speed changing on its own.

Slower (dodgy motor / drive)

or faster (slipping roller) ?

In article
, Jim K
wrote:
On Aug 10, 10:28 am, "Dave Plowman (News)" wrote:
In article
,
Andy Dingley wrote:

On 10 Aug, 10:06, "Dave Plowman (News)" wrote:
As regards the wire drive motor I was thinking along the lines of
converting it to PWM drive. Assuming it's not already.
If it's anything like SIPs I've previous done battle with, it's not
the motor that's the problem, it's the roller drive's inability to
grip the wire.

That bit seems ok on mine - you can adjust the friction between the
drive wheel and wire. But the actual speed varies dramatically at the
slow end which is where it's critical for me. You can here the motor
speed changing on its own.

when my sh1tty draper mig's wire feed slipped (sh1t rollers too) the
motor sound/pitch would change too....

Presumably it slips because of increased drag somewhere on the wire?
There is a mod said to help which involves a steel strap between the
roller bearing arm pivot and a drive roller housing fixing screw - said to
stop the plastic flexing.

However, if you remove the wire and run the motor at slow speeds, you can
slow it down easily by gripping the drive wheel. Much more difficult with
PWM drive.

Thing is I had all the bits lying around for this mod. Buying new might
not make it cost effective. I should finish it tomorrow and will report on
whether it actually makes welding thin stuff easier.

--
*Filthy stinking rich -- well, two out of three ain't bad

Dave Plowman London SW
To e-mail, change noise into sound.

In article
,
Andy Dingley wrote:
On 10 Aug, 10:28, "Dave Plowman (News)" wrote:

You can here the motor speed changing on its own.

Slower (dodgy motor / drive)

or faster (slipping roller) ?

My guess is not enough torque from the motor at slow speeds.

--
*"I am " is reportedly the shortest sentence in the English language. *

Dave Plowman London SW
To e-mail, change noise into sound.