I'm currently restoring a 1971 VW Beetle 1300.
I can handle the mechanical work no problem at all, but I'm having
trouble with the welding.

I have both an electric arc welder, and a Mig welder, but have not
been getting great results with either. Mainly I keep blowing holes
through the existing metal (its thin!) when trying to weld patches in.
I've tried turning down the power and so on, but after much practising
and cursing I'm still not getting very good results.

With the arc welder I'm using 1.6mm rods with the power turned down to
about the lowest the machine will go to.

With the mig I think the fact that I'm working outside causes the gas
to get blown away too easily, and gasless mig wire (I'm told) is no
use on old, thin metal like the Beetle.

Anyway, if anyone has any tips or links to good welding sites I'd love
to hear about them.

Or if anyone lives near Kirkintilloch (Glasgow) and would like to earn
a few quid giving me a few lessons I's love to hear from you too!!!

kenny [no space] millar [at] mac [dot] com

"kmillar" wrote in message
ps.com...
I'm currently restoring a 1971 VW Beetle 1300.
I can handle the mechanical work no problem at all, but I'm having
trouble with the welding.

I have both an electric arc welder, and a Mig welder, but have not
been getting great results with either. Mainly I keep blowing holes
through the existing metal (its thin!) when trying to weld patches in.
I've tried turning down the power and so on, but after much practising
and cursing I'm still not getting very good results.

With the arc welder I'm using 1.6mm rods with the power turned down to
about the lowest the machine will go to.

You'll not really stand much chance with 1.6 rods MMA welding on car body
stuff, it's just too thin. If you're using a cheap 'buzz-box' welder then
you're really fighting an uphill battle - you're in with a better chance
with an inverter welder. But really you have TIG, MIG or gas at your
disposal and that's your lot.



With the mig I think the fact that I'm working outside causes the gas
to get blown away too easily, and gasless mig wire (I'm told) is no
use on old, thin metal like the Beetle.

I don't have enough experience with mig to comment meaningfully because I'm
still on oxy-acet, but the gas you use is important I believe as is getting
the metal totally clean of rust first.



Anyway, if anyone has any tips or links to good welding sites I'd love
to hear about them.

There is at least one very good welding news group, last time I made an
enquiry I had more good advice than you could shake a stick at.
sci.eng.joining.welding I think was the one.

Julian.

"kmillar" wrote in message
ps.com...
I'm currently restoring a 1971 VW Beetle 1300.
I can handle the mechanical work no problem at all, but I'm having
trouble with the welding.

I have both an electric arc welder, and a Mig welder, but have not
been getting great results with either.

snip

Forget the arc... even Noah couldn't MMA weld very thin steel.

With the mig I think the fact that I'm working outside causes the gas
to get blown away too easily,

possibly, but you can always turn the gas flow up a bit, or try to
shield yourself from the wind, and the main ill effect is a
dirty-looking, weak weld.

Anyway, if anyone has any tips or links to good welding sites I'd love
to hear about them.

Check your technique by running a bead on a piece of bright, new steel
of the same thickness that you're trying to weld on the car - say 20g,
or 1mm. If that works OK, but you struggle with the car, it's probably
because you haven't got it clean enough. It's the big shock to anyone
converting to MIG from oxy-acetylene, where you can make a passable job
welding through paint and rust. With MIG, it really does have to be
bright and shiny to keep the weld going smoothly. Make sure you've got
a really good earth connection - if necessary clean up somewhere with a
grinder for your earth clamp.

Learn to recognise the sizzle of MIG welding working properly - if it's
all spit and pop you're doing something wrong. Use an auto-darkening
helmet and a good pair of leather gauntlets

Then practice again, and again. There's a world of difference between
being able to MIG weld, say, a trailer chassis from new 3mm steel angle
in a textbook welding position and patching an old car where you simply
cannot achieve the "correct" torch angles or directions.


--
Kevin Poole
**Use current month and year to reply (e.g. )***

Julian,

Thanks for the advice!
I think I'll spend tomorrow in the garage practising with the mig.

-Kenny

On Aug 1, 9:39 pm, "Julian" wrote:
"kmillar" wrote in message

ps.com...

I'm currently restoring a 1971 VW Beetle 1300.
I can handle the mechanical work no problem at all, but I'm having
trouble with the welding.

I have both an electric arc welder, and a Mig welder, but have not
been getting great results with either. Mainly I keep blowing holes
through the existing metal (its thin!) when trying to weld patches in.
I've tried turning down the power and so on, but after much practising
and cursing I'm still not getting very good results.

With the arc welder I'm using 1.6mm rods with the power turned down to
about the lowest the machine will go to.

You'll not really stand much chance with 1.6 rods MMA welding on car body
stuff, it's just too thin. If you're using a cheap 'buzz-box' welder then
you're really fighting an uphill battle - you're in with a better chance
with an inverter welder. But really you have TIG, MIG or gas at your
disposal and that's your lot.



With the mig I think the fact that I'm working outside causes the gas
to get blown away too easily, and gasless mig wire (I'm told) is no
use on old, thin metal like the Beetle.

I don't have enough experience with mig to comment meaningfully because I'm
still on oxy-acet, but the gas you use is important I believe as is getting
the metal totally clean of rust first.



Anyway, if anyone has any tips or links to good welding sites I'd love
to hear about them.

There is at least one very good welding news group, last time I made an
enquiry I had more good advice than you could shake a stick at.
sci.eng.joining.welding I think was the one.

Julian.

On Wed, 01 Aug 2007 13:20:03 -0700, kmillar wrote:

I'm currently restoring a 1971 VW Beetle 1300. I can handle the
mechanical work no problem at all, but I'm having trouble with the
welding.

I have both an electric arc welder, and a Mig welder, but have not been
getting great results with either. Mainly I keep blowing holes through
the existing metal (its thin!) when trying to weld patches in. I've
tried turning down the power and so on, but after much practising and
cursing I'm still not getting very good results.

With the arc welder I'm using 1.6mm rods with the power turned down to
about the lowest the machine will go to.

With the mig I think the fact that I'm working outside causes the gas to
get blown away too easily, and gasless mig wire (I'm told) is no use on
old, thin metal like the Beetle.

Anyway, if anyone has any tips or links to good welding sites I'd love
to hear about them.

Or if anyone lives near Kirkintilloch (Glasgow) and would like to earn a
few quid giving me a few lessons I's love to hear from you too!!!

kenny [no space] millar [at] mac [dot] com

==================================
As already advised, forget the arc welder.

You say that the metal is thin so I would suggest that you may be trying
to make your repair patches too small. When you cut out rusted areas cut
back to good solid metal which usually means cutting much more than first
appearances suggest. The metal of a Beetle of the age you're working on
should be thick enough to be easily welded with either Mig or gas.

In non critical areas (bonnet, wings etc.) you can use your Mig welder as
a spot welder. Drill holes (about 3/8") around the edge of your patches,
clamp in place and create a weld pool through the holes until you form a
little 'mushroom' weld.

Cic.

--
===================================
Using Ubuntu Linux
Windows shown the door
===================================

Thanks Kevin, That's great advice.
I'll spend some more time practising!

The thing you said about the trailer welding is so true, I bought the
Mig thinking I'd be good at it, because at college WAY back in 1987 I
was great at welding - top of the class! But it was on seriously heavy
metal - like 8mm thick.

-K

On Aug 1, 9:49 pm, "Autolycus" wrote:
"kmillar" wrote in message

ps.com...

I'm currently restoring a 1971 VW Beetle 1300.
I can handle the mechanical work no problem at all, but I'm having
trouble with the welding.

I have both an electric arc welder, and a Mig welder, but have not
been getting great results with either.

snip

Forget the arc... even Noah couldn't MMA weld very thin steel.



With the mig I think the fact that I'm working outside causes the gas
to get blown away too easily,

possibly, but you can always turn the gas flow up a bit, or try to
shield yourself from the wind, and the main ill effect is a
dirty-looking, weak weld.

Anyway, if anyone has any tips or links to good welding sites I'd love
to hear about them.

Check your technique by running a bead on a piece of bright, new steel
of the same thickness that you're trying to weld on the car - say 20g,
or 1mm. If that works OK, but you struggle with the car, it's probably
because you haven't got it clean enough. It's the big shock to anyone
converting to MIG from oxy-acetylene, where you can make a passable job
welding through paint and rust. With MIG, it really does have to be
bright and shiny to keep the weld going smoothly. Make sure you've got
a really good earth connection - if necessary clean up somewhere with a
grinder for your earth clamp.

Learn to recognise the sizzle of MIG welding working properly - if it's
all spit and pop you're doing something wrong. Use an auto-darkening
helmet and a good pair of leather gauntlets

Then practice again, and again. There's a world of difference between
being able to MIG weld, say, a trailer chassis from new 3mm steel angle
in a textbook welding position and patching an old car where you simply
cannot achieve the "correct" torch angles or directions.

--
Kevin Poole
**Use current month and year to reply (e.g. )***

On Aug 1, 10:20 pm, Cicero wrote:
On Wed, 01 Aug 2007 13:20:03 -0700, kmillar wrote:
I'm currently restoring a 1971 VW Beetle 1300. I can handle the
mechanical work no problem at all, but I'm having trouble with the
welding.

I have both an electric arc welder, and a Mig welder, but have not been
getting great results with either. Mainly I keep blowing holes through
the existing metal (its thin!) when trying to weld patches in. I've
tried turning down the power and so on, but after much practising and
cursing I'm still not getting very good results.

With the arc welder I'm using 1.6mm rods with the power turned down to
about the lowest the machine will go to.

With the mig I think the fact that I'm working outside causes the gas to
get blown away too easily, and gasless mig wire (I'm told) is no use on
old, thin metal like the Beetle.

Anyway, if anyone has any tips or links to good welding sites I'd love
to hear about them.

Or if anyone lives near Kirkintilloch (Glasgow) and would like to earn a
few quid giving me a few lessons I's love to hear from you too!!!

kenny [no space] millar [at] mac [dot] com

==================================
As already advised, forget the arc welder.

You say that the metal is thin so I would suggest that you may be trying
to make your repair patches too small. When you cut out rusted areas cut
back to good solid metal which usually means cutting much more than first
appearances suggest. The metal of a Beetle of the age you're working on
should be thick enough to be easily welded with either Mig or gas.

In non critical areas (bonnet, wings etc.) you can use your Mig welder as
a spot welder. Drill holes (about 3/8") around the edge of your patches,
clamp in place and create a weld pool through the holes until you form a
little 'mushroom' weld.

Cic.

--
===================================
Using Ubuntu Linux
Windows shown the door
===================================

Thanks for the advice!
I did cut quite far back - definately into good clean metal - but I'll
keep at it.
Thanks for all the advice.

In article om,
kmillar wrote:
I have both an electric arc welder, and a Mig welder, but have not
been getting great results with either. Mainly I keep blowing holes
through the existing metal (its thin!) when trying to weld patches in.
I've tried turning down the power and so on, but after much practising
and cursing I'm still not getting very good results.

You're trying to butt weld in patches? Just about the most difficult thing
to do even with a good MIG and practice. A joddled joint is much easier.

--
*I don't suffer from insanity -- I'm a carrier

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

In article .com,
kmillar writes
Thanks Kevin, That's great advice.
I'll spend some more time practising!

The thing you said about the trailer welding is so true, I bought the
Mig thinking I'd be good at it, because at college WAY back in 1987 I
was great at welding - top of the class! But it was on seriously heavy
metal - like 8mm thick.

Ah!, thats metal gluing....
--
Tony Sayer

On Wed, 01 Aug 2007 13:20:03 -0700, kmillar wrote:

I'm currently restoring a 1971 VW Beetle 1300.

Learn to weld first. Get your MIG, a wheelbarrow full of scrap steel
(thickish stuff, not 20 gauge) and practice on heavy gauge until you've
got the technique spot on. Turn the dials right up, especially the feed
rate, and learn the _process_ first, only worry about toning it down for
thin sheet afterwards.

Also learn how the process ought to work. I'd suggest Gibson's
"Practical Welding" as 10-15 quid well spent, but these days you can
probably get a reasonable defintion from wikipedia. You _must_ learn
what "spray transfer", "constant voltage" and similar terms mean in the
MIG context. It's not much to learn, but it's important. You'll never
judge what's going wrong unless you know a tiny background to _how_
it;'s supposed to work.

Also, use decent shield gas (which _will_ cost you bottle rental) rather
than CO2 from the pub.

If you can find / buy one, an automatic helmet is well worth it (70ish
quid these days)

Also it's a Beetle (or a Moggy Minor), either of which is easier (ie
thicker) sheet steel to weld than a Ford Escrote, or (&deity; forbid) an
unweldable Ford Sierra.

sci.engr.joining.welding and searching this group's archives hould be
helpful too.

"Andy Dingley" wrote in message
...
On Wed, 01 Aug 2007 13:20:03 -0700, kmillar wrote:

I'm currently restoring a 1971 VW Beetle 1300.

I have found this site and intend to have a run through the tutorials when
I get the time

http://www.mig-welding.co.uk/

It looks good but I have yet to see whether it will help


Tony

On 1 Aug, 21:20, kmillar wrote:

I'm currently restoring a 1971 VW Beetle 1300.
I can handle the mechanical work no problem at all, but I'm having
trouble with the welding.

I did cut quite far back - definately into good clean metal - but I'll
keep at it.
Thanks for all the advice.

IME youve got to go much further than that. What looks & feels good &
sound is still too thin to survive welding. ISTR a few inches further
all round was needed, but am not 100% on that.

Last time I welded one up I used gasless wire, and it went very well.
Joy to use actually.

One of the biggest issues with welding thin sheet is that most welders
dont go down low enough to do it, and the excess heat just blows a
hole. The sales pitch seems to be about big numbers, you only learn
you need smaller currents later.

Arc welders are widely used in poor coutries for car work, but anyone
who's used one knows their downsides. The plus point is that if you
can use arc, gasless wire is much easier.


NT

On Wed, 01 Aug 2007 23:43:43 +0100, Andy Dingley
wrote:


Also it's a Beetle (or a Moggy Minor), either of which is easier (ie
thicker) sheet steel to weld than a Ford Escrote, or (&deity; forbid) an
unweldable Ford Sierra.

Hmm, I migged strut tops and sills on the Mk1 and one sill, foot well
and quite a bit around the n/s rear cargo bay (floor, inner arch,
chassis) on my 83 Sierra Estate and it all went ok?

Scrapped it at 23 yrs old with an MOT cos I had too many cars ;-(

All the best ..

T i m

On Thu, 2 Aug 2007 08:39:20 +0100, "TMC" wrote:

"Andy Dingley" wrote in message
.. .
On Wed, 01 Aug 2007 13:20:03 -0700, kmillar wrote:

I'm currently restoring a 1971 VW Beetle 1300.

I have found this site and intend to have a run through the tutorials when
I get the time

http://www.mig-welding.co.uk/

It looks good but I have yet to see whether it will help


Tony


Please don't forge posts to look as if you're quoting one of my posts,
and suggesting that I recommended it. Coupled with your faked posting
headers, this looks an awful lot as if you're spamming your own site.

As for the quality of the site's tutorials, then they're pretty
worthless. They're notes from one amateur welder, only using DIY-grade
kit, who has found one technique that works for them on one class of
work and they've described what they can see.

The trouble with this is that it teaches nothing of _why_ some
techniques work and some don't. There's no _understanding_ behind any of
this. How can anything claiming to be a MIG tutorial fail to mention:

* gas choice

* transfer mode (this site seems to think there's a single continuum
with a single optimum)

* positional welding beyond "push" and "pull"

There's no shortage of good tutorial material out there. We don't need
this one.

Also, use decent shield gas (which _will_ cost you bottle rental) rather
than CO2 from the pub.


Two words, argon mix. I never weld without it. Also welding
different thicknesses togther can be tricky - you need to weld more on
the thicker new stuff and let it melt into the thinner stuff but
really you should be getting rid of thin stuff and repaling it with
all new. ...for a resto. For quick & nasty get you thru the MoT then
it's a different matter.

On 2 Aug, 18:26, T i m wrote:

(&deity; forbid) an unweldable Ford Sierra.

Hmm, I migged strut tops and sills on the Mk1 and one sill, foot well
and quite a bit around the n/s rear cargo bay (floor, inner arch,
chassis) on my 83 Sierra Estate and it all went ok?

Rear panels, esp. around the rear axle of a Sierra are a high-tensile
steel (chosen so that Ford can make it thinner, lighter and cheaper).
It's not weldable without care, and if you aren't careful, you weaken
it. Naturally these thin panels are also the ones that tended to need
the welding.

Use your hoof on a powerful Sierra, like a Cosworth or a V6, and you
can get all sorts of problems where the rear axle wants to pull itself
free from the bodyshell. Similarly for estates that are over-loaded by
lumberjacks!

It's a bit like bike frames and the 753 / 853 tubing. 853 is stronger
owing to a complicated factory heat-treat process, so the tubes were
often made thinner. You can over-heat either and still get a joint,
but of you do it to 853, you convert it back to mere 753 afterwards.

On Aug 2, 8:45 pm, Andy Dingley wrote:
On Thu, 2 Aug 2007 08:39:20 +0100, "TMC" wrote:

"Andy Dingley" wrote in message
.. .
On Wed, 01 Aug 2007 13:20:03 -0700, kmillar wrote:

I'm currently restoring a 1971 VW Beetle 1300.

I have found this site and intend to have a run through the tutorials when
I get the time

http://www.mig-welding.co.uk/

It looks good but I have yet to see whether it will help

Tony

Please don't forge posts to look as if you're quoting one of my posts,
and suggesting that I recommended it. Coupled with your faked posting
headers, this looks an awful lot as if you're spamming your own site.

See some of his other posts. I think he actually wrote what looks like
your post being quoted. No subterfuge, he's just incompetent at
quoting properly.

MBQ

On 2 Aug, 13:49, wrote:

One of the biggest issues with welding thin sheet is that most welders
dont go down low enough to do it, and the excess heat just blows a
hole. The sales pitch seems to be about big numbers, you only learn
you need smaller currents later.

You can MIG weld thin sheet with a huge current (if you're doing
enough of it, quickly enough), you just need to be even more careful
about the manual skills of controlling the weld pool. Big weld pools
on thin sheet are tricky! A MIG welder is a constant voltage device,
so the current just tracks the demands you make of it, it's not a
control input.

What most DIY users don't realise is that the "current control" is
actually the wire speed (or maybe that the wire speed is also the
current control!). The amount of wire you feed has a huge effect on
the current and thus the neat input. This is why when lerning, one of
the first things you should do is to investigate the effects of
turning wire feed right up and using spray transfer mode.

One of the biggest issues with welding thin sheet is that most welders
dont go down low enough to do it, and the excess heat just blows a
hole. The sales pitch seems to be about big numbers, you only learn
you need smaller currents later.


I think you have hit the nail on the head there.
You can see some pictures of my beetle, and my welder at
http://web.mac.com/kennymillar/iWeb/...e%20Resto.html where
there is also a picture of the power rating plate on my welder.

I took the advice above and practiced on a bucket load of scrap metal
- cut from the original wings from the same car, and got it clean of
all rust and paint, down to nice clean shiny metal and just tried
running beads of weld along it - again I just ended up blowing holes
right through the metal - I was finding it impossible to get a bead.

I have read some books and web sites on mig welding technique, and on
thicker metal I can get reasonable results, but on this body work
metal I just cant.

Thanks again for all the help so far!

-Kenny

On Fri, 03 Aug 2007 02:40:44 -0700, Andy Dingley
wrote:

On 2 Aug, 18:26, T i m wrote:

(&deity; forbid) an unweldable Ford Sierra.

Hmm, I migged strut tops and sills on the Mk1 and one sill, foot well
and quite a bit around the n/s rear cargo bay (floor, inner arch,
chassis) on my 83 Sierra Estate and it all went ok?

Rear panels, esp. around the rear axle of a Sierra are a high-tensile
steel (chosen so that Ford can make it thinner, lighter and cheaper).

If you left of the cheaper bit it could sound like racing spec stuff
Andy ;-)

It's not weldable without care, and if you aren't careful, you weaken
it. Naturally these thin panels are also the ones that tended to need
the welding.

Mine only needed doing at the back (along with along the side (sill /
floor pan) because of poor post-accident damage repairs. The rear
glass had to be changed when some bright spark tried to cut it out
(via the rubber) only to find it was direct bonded to the tailgate.
The re bonded glass must have been leaking, rotting the tailgate out
and filling the under floor up with water (on the ns). Ns sill / floor
was solid but o/s was hit by a truck and badly repaired (again,
leaking and that killed it).

Use your hoof on a powerful Sierra, like a Cosworth or a V6, and you
can get all sorts of problems where the rear axle wants to pull itself
free from the bodyshell.

Understood, this was only a SOHC 2L but sill pretty lively compared
with the 1.4i Astra and 218SD Rover we have now!.

Similarly for estates that are over-loaded by
lumberjacks!

Well, I can't say it was *never* 'well loaded' .. weg. I tell you
though, I really miss that old workhorse. L o n g flat loading area
and the bay rear glass would enclose stuff that was sticking beyond
the rear body line. A l o n g roof with real gutters and Thule roof
bars that carried all sorts of (5m long) things. Towed all sorts of
things with little effort and in 98,000 miles never let us down (I
lie, a cam belt at 90K+ 500 yards from home, a seizing front caliper
that got us home slowly and a broken clutch cable but I carried a
spare).

It's a bit like bike frames and the 753 / 853 tubing. 853 is stronger
owing to a complicated factory heat-treat process, so the tubes were
often made thinner. You can over-heat either and still get a joint,
but of you do it to 853, you convert it back to mere 753 afterwards.

Understood.

A mate of mine runs his own photo copier Co and was telling me about
what happens to all the older kit he pulls back off site after lease /
rental etc.

All the really old clunky electro / mechanical stuff get's exported to
Africa / India where they can easily repair it and keep it running.

When he offered the exporter a much later colour jobby he said 'no
thanks' (as he knew it was un repairable).

Similar to a relative who has a Pug 106 going spare. It's chucking out
black smoke and the repair could be expensive. If it's the lambda
sensor (£100?) cat (£150?[1]), fuel injector pump (£150?) or computer
(£150 exchange) ..?

How much energy / pollution would fixing it create compared with my
very basic but 'dirty' 1300 Kent powered kit car which is easily /
cheaply fixable?

All the best ..

T i m

[1] Would need changing as now anyway as it's 'polluted'?

What most DIY users don't realise is that the "current control" is
actually the wire speed (or maybe that the wire speed is also the
current control!). The amount of wire you feed has a huge effect on
the current and thus the neat input. This is why when lerning, one of
the first things you should do is to investigate the effects of
turning wire feed right up and using spray transfer mode.

That sounds like the sort of thing I need to learn! Thanks for the
advice.

-Kenny

In article .com,
kmillar wrote:
I took the advice above and practiced on a bucket load of scrap metal
- cut from the original wings from the same car, and got it clean of
all rust and paint, down to nice clean shiny metal and just tried
running beads of weld along it - again I just ended up blowing holes
right through the metal - I was finding it impossible to get a bead.

As an apprentice welder with a MIG I can tell you that bit's easy. I can
do a near perfect bead down a sheet of steel. What defeated me was a butt
joint - the one thing I really wanted to do.

--
*Gaffer tape - The Force, light and dark sides - holds the universe together*

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

kmillar wrote:
One of the biggest issues with welding thin sheet is that most welders
dont go down low enough to do it, and the excess heat just blows a
hole. The sales pitch seems to be about big numbers, you only learn
you need smaller currents later.


I think you have hit the nail on the head there.
You can see some pictures of my beetle, and my welder at
http://web.mac.com/kennymillar/iWeb/...e%20Resto.html where
there is also a picture of the power rating plate on my welder.

I took the advice above and practiced on a bucket load of scrap metal
- cut from the original wings from the same car, and got it clean of
all rust and paint, down to nice clean shiny metal and just tried
running beads of weld along it - again I just ended up blowing holes
right through the metal - I was finding it impossible to get a bead.

I have read some books and web sites on mig welding technique, and on
thicker metal I can get reasonable results, but on this body work
metal I just cant.

Thanks again for all the help so far!

-Kenny


Consider a blowtorch and BRAZING. Its more than strong enough for
bodywork. I wouldn't do it on a chassis,but it is fine on a wing or
something.

"The Natural Philosopher" wrote in message
...
kmillar wrote:




Consider a blowtorch and BRAZING. Its more than strong enough for
bodywork. I wouldn't do it on a chassis,but it is fine on a wing or
something.


That would be a disaster! With a blowtorch you'd feed so much heat into a
large area of metal that it would warp and buckle like a bugger (and prolly
set the vehicle alight!) The only real way to braze car body is with
oxy-acet, but then you'd (normally) be better off with steel filler rod and
weld the joint.

BTW there are issues with braze repairs WRT MOT's. Older vehicles must be
welded IIRC. However, I believe that new vehicles are increasingly using
boron steel in their construction, and a Thatchem approved repair must be
MIG brazed - welding is unacceptable because the temperatures reached
destroy the steel's heat treatment.

Julian.

In article ,
The Natural Philosopher wrote:
Consider a blowtorch and BRAZING. Its more than strong enough for
bodywork. I wouldn't do it on a chassis,but it is fine on a wing or
something.

Not suitable where an MOT man might be interested. And very difficult to
prevent distortion on a panel due to the general heat needed.

--
*I don't suffer from insanity -- I'm a carrier

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

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Andy Dingley
saying something like:

I have found this site and intend to have a run through the tutorials when
I get the time

http://www.mig-welding.co.uk/

It looks good but I have yet to see whether it will help


Tony


Please don't forge posts to look as if you're quoting one of my posts,
and suggesting that I recommended it. Coupled with your faked posting
headers, this looks an awful lot as if you're spamming your own site.

Looks like the site is run by Malcom Vardy and nothing to do with this
Tony geezer, afaics.
--

Dave

"AJH" wrote in message
...
On Fri, 03 Aug 2007 03:39:38 -0700, Andy Dingley
wrote:

What most DIY users don't realise is that the "current control" is
actually the wire speed (or maybe that the wire speed is also the
current control!). The amount of wire you feed has a huge effect on
the current and thus the neat input.

Probably why most small migs are pants.

Has anyone tried one of the new inverter welders that can be used with
stick, tig or reel feed? I suppose they use electronics to mimic the
droop characteristics of each mode?

I've got a 200A inverter welder that does only stick. It's fantastic and
welds as smoothly as the old 'Oxford' oil cooled transformer welders. The
rod doesn't stick, striking up is easy and it is happy at the end of a long
extension lead - something that my old buzz box welder wouldn't really
tolerate. I think it is also more efficient, because I haven't had to
substitute the 13amp fuse with a 5/16'' bolt yet when on 3.2mm rods :-)

Julian.

AJH wrote:
On Sat, 04 Aug 2007 11:46:22 +0100, The Natural Philosopher
wrote:

Consider a blowtorch and BRAZING. Its more than strong enough for
bodywork. I wouldn't do it on a chassis,but it is fine on a wing or
something.

I don't think this is acceptable for MOT anymore, it must be
continuous welds. Apart from that brazing with gas tends to put a lot
more heat into a sheet compared with mig, so more distortion and
damage to adjacent paintwork.

I don't think that applies to non structural repairs. Certainly I
wouldn't braze a sill box member..but I am fairly sure brazing is fine
for making good holes in e.g. skins. I mean, if you canu se car body
filler...;-)

AJH

Dave Plowman (News) wrote:
In article ,
The Natural Philosopher wrote:
Consider a blowtorch and BRAZING. Its more than strong enough for
bodywork. I wouldn't do it on a chassis,but it is fine on a wing or
something.

Not suitable where an MOT man might be interested. And very difficult to
prevent distortion on a panel due to the general heat needed.

Solder then, :-)

"The Natural Philosopher" wrote in message
...
Dave Plowman (News) wrote:
In article ,
The Natural Philosopher wrote:
Consider a blowtorch and BRAZING. Its more than strong enough for
bodywork. I wouldn't do it on a chassis,but it is fine on a wing or
something.

Not suitable where an MOT man might be interested. And very difficult to
prevent distortion on a panel due to the general heat needed.

Solder then, :-)

That's more like it! I've got a car full of it. (lead-loading - just like a
wiped joint on a lead pipe) So much better than resin filler....

Julian.

In article ,
Julian wrote:
That's more like it! I've got a car full of it. (lead-loading - just
like a wiped joint on a lead pipe) So much better than resin filler....

I'm not sure it is - corrosion tends to start between the lead and steel.

--
*People want trepanners like they want a hole in the head*

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

On Sat, 04 Aug 2007 16:01:43 +0000, Julian wrote:


"The Natural Philosopher" wrote in message
...
Dave Plowman (News) wrote:
In article ,
The Natural Philosopher wrote:
Consider a blowtorch and BRAZING. Its more than strong enough for
bodywork. I wouldn't do it on a chassis,but it is fine on a wing or
something.

Not suitable where an MOT man might be interested. And very difficult
to prevent distortion on a panel due to the general heat needed.

Solder then, :-)

That's more like it! I've got a car full of it. (lead-loading - just like
a wiped joint on a lead pipe) So much better than resin filler....

Julian.

==================================
Didn't you find it difficult to sand to a decent finish? When I tried it
it clogged the paper constantly even using 'wet and dry'. Standard body
filler seems to be the modern way.

Cic.

--
===================================
Using Ubuntu Linux
Windows shown the door
===================================

On Sat, 04 Aug 2007 11:46:22 +0100, The Natural Philosopher
wrote:

Consider a blowtorch and BRAZING. Its more than strong enough for
bodywork.

Not on sheetmetal it isn't. Although there are brazed "birdcage" tube
chassis around, brazing alone on a thin sheet monocoque is a _terrible_
idea. It'll hold together, it'll even be strong when first made. However
any cracking that does develop (and it will) has a huge risk of truning
into an instant "zipper" fracture and the whole seam splitting.

If you're going to braze to waterproof, then at least stitch weld it
first.

There's also the issue (crazy as it might be) that it's an instant MOT
failure.

I wouldn't do it on a chassis,

This is a Beetle we're talking about. Although it does pretty much have
a "chassis" (you can rip the floorpan out of a Beetle and use it as a
separate chassis without too much trouble, hence the plastic bathtub
beach bugy), it's still a major structural component that's designed
around an integral monocoque of thin stressed sheetmetal.


You're getting to be as bad as Drivel...

On Sat, 04 Aug 2007 16:31:48 +0100, The Natural Philosopher
wrote:

I don't think that applies to non structural repairs.

read the tester's handbook or STFU

On Sat, 04 Aug 2007 18:04:27 GMT, Cicero
wrote:

Didn't you find it difficult to sand to a decent finish?

You don't sand lead-loading, you use a rasp.

A _clean_ rasp (otherwise it pins), which from time to time you clean
with gunshop lead fouling remover.

"Andy Dingley" wrote in message
...


There's also the issue (crazy as it might be) that it's an instant MOT
failure.

Even though the some old Astons had steering linkage fabricated by
brazing....

Julian

"Dave Plowman (News)" wrote in message
...
In article ,
Julian wrote:
That's more like it! I've got a car full of it. (lead-loading - just
like a wiped joint on a lead pipe) So much better than resin filler....

I'm not sure it is - corrosion tends to start between the lead and steel.

I suppose if you're using to slap over rust then yes, it prolly does. But
I'll bet you a £ to a penny that in similar circumstances corrosion will
bleed through a 'repair' with resin almost overnight.

But the above is purely theoretical of course, nobody here would slap the
stuff straight over a rusty hole or scabby metal - would they!

Julian.

"Cicero" wrote in message
news
On Sat, 04 Aug 2007 16:01:43 +0000, Julian wrote:


"The Natural Philosopher" wrote in message
...
Dave Plowman (News) wrote:
In article ,
The Natural Philosopher wrote:
Consider a blowtorch and BRAZING. Its more than strong enough for
bodywork. I wouldn't do it on a chassis,but it is fine on a wing or
something.

Not suitable where an MOT man might be interested. And very difficult
to prevent distortion on a panel due to the general heat needed.

Solder then, :-)

That's more like it! I've got a car full of it. (lead-loading - just like
a wiped joint on a lead pipe) So much better than resin filler....

Julian.

==================================
Didn't you find it difficult to sand to a decent finish? When I tried it
it clogged the paper constantly even using 'wet and dry'. Standard body
filler seems to be the modern way.

As has been pointed out you need a rasp or file.

Just a small word of warning, (and I try hard to distance myself from the
modern phenomenon of the safety Nazi culture) sanding lead produces dust
which is not too good for health if you breath enough of it in.

Julian.

On Sat, 04 Aug 2007 20:08:06 +0100, Andy Dingley wrote:

On Sat, 04 Aug 2007 18:04:27 GMT, Cicero wrote:

Didn't you find it difficult to sand to a decent finish?

You don't sand lead-loading, you use a rasp.

A _clean_ rasp (otherwise it pins), which from time to time you clean with
gunshop lead fouling remover.

==================================
I tried it (lead loading) because I saw it being done on expensive Jaguar
renovations near Bridgnorth. They used ordinary grinding disks on an angle
grinder which looked pretty clogged up to me. Maybe I only saw the start
of the process but there was no obvious use of other tools in evidence.

If I ever feel the urge to try lead loading again I'll remember to try a
rasp which I've used on roofing lead to shape around pipes etc.

Cic.

--
===================================
Using Ubuntu Linux
Windows shown the door
===================================

On Sat, 04 Aug 2007 19:55:15 +0000, Julian wrote:


"Cicero" wrote in message
news
On Sat, 04 Aug 2007 16:01:43 +0000, Julian wrote:


"The Natural Philosopher" wrote in message
...
Dave Plowman (News) wrote:
In article ,
The Natural Philosopher wrote:
Consider a blowtorch and BRAZING. Its more than strong enough for
bodywork. I wouldn't do it on a chassis,but it is fine on a wing or
something.

Not suitable where an MOT man might be interested. And very difficult
to prevent distortion on a panel due to the general heat needed.

Solder then, :-)

That's more like it! I've got a car full of it. (lead-loading - just
like a wiped joint on a lead pipe) So much better than resin filler....

Julian.

==================================
Didn't you find it difficult to sand to a decent finish? When I tried it
it clogged the paper constantly even using 'wet and dry'. Standard body
filler seems to be the modern way.

As has been pointed out you need a rasp or file.

Just a small word of warning, (and I try hard to distance myself from the
modern phenomenon of the safety Nazi culture) sanding lead produces dust
which is not too good for health if you breath enough of it in.

Julian.

==================================
Point taken - health warnings are never out of place, I think. There
will always be somebody seeing them for the first time.

Cic.

--
===================================
Using Ubuntu Linux
Windows shown the door
===================================