I'm fixing up a 1964 Qualcast Commodore cylinder lawnmower. Great success
yesterday, and managed to give my lawn its first decent cut for years!

However, the steel petrol tank is corroded and is leaking at the bottom. I
have dried it out, given it a few bashes, and shaken out quite a lot of
scale. What should I do next? My thoughts are one of the following:

- Pour in a two part resin mix, enough to cover / coat the bottom of the
tank, where the corrosion has been. I suppose I could use either epoxy
(expensive) or polyester (cheaper).

- Bare the outside of the tank and coat with one of the above resins (with
fibreglass matting?).

- Apply petropatch or similar proprietary patch on outside.

Any advice, please?

Thanks
Steve

"Steve W" wrote in message
...
I'm fixing up a 1964 Qualcast Commodore cylinder lawnmower. Great success
yesterday, and managed to give my lawn its first decent cut for years!

However, the steel petrol tank is corroded and is leaking at the bottom.
I have dried it out, given it a few bashes, and shaken out quite a lot of
scale. What should I do next? My thoughts are one of the following:

- Pour in a two part resin mix, enough to cover / coat the bottom of the
tank, where the corrosion has been. I suppose I could use either epoxy
(expensive) or polyester (cheaper).

- Bare the outside of the tank and coat with one of the above resins (with
fibreglass matting?).

- Apply petropatch or similar proprietary patch on outside.

Any advice, please?

Thanks
Steve

You don't say whether you want to preserve the finish on the tank as a
restoration for show, or just to use?

If the finish is not important, or you are able to repaint it yourself, and
the metal is not too far gone, you should be able to have it brazed
(especially true if it is just the 'usual' cracking around the tap spigot).
If it's just the seam that is weeping you might even be able to heat the
whole thing up and run some solder down the seam inside. BUT DO make
absolutely sure there is no smell of petrol from the tank before you get any
source of ignition anywhere near it. An 'empty' tank is essentially an
unexploded bomb.

If the metal is too far gone, I would imagine that 'internal solutions' are
more likely to keep any holes filled than external. You might even be able
to line the tank with some kind of 'bag' if you were just looking to it as a
supporting structure. Wonder if one of those shiny wine/cider bags from
inside the cartons might be coaxed into service...

Dangerous mucking about with petrol though...

S

Spamlet wrote:

If the finish is not important, or you are able to repaint it yourself, and
the metal is not too far gone, you should be able to have it brazed
(especially true if it is just the 'usual' cracking around the tap spigot).
If it's just the seam that is weeping you might even be able to heat the
whole thing up and run some solder down the seam inside. BUT DO make
absolutely sure there is no smell of petrol from the tank before you get any
source of ignition anywhere near it. An 'empty' tank is essentially an
unexploded bomb.


Saw the answer to that on Scrapheap Challenge the other day - they were
making a diving helmet from an old Calor cylinder, and needed to cut it
in half.

So they filled it with water first.

Andy

Andy Champ wrote :
Spamlet wrote:

If the finish is not important, or you are able to repaint it yourself, and
the metal is not too far gone, you should be able to have it brazed
(especially true if it is just the 'usual' cracking around the tap spigot).
If it's just the seam that is weeping you might even be able to heat the
whole thing up and run some solder down the seam inside. BUT DO make
absolutely sure there is no smell of petrol from the tank before you get
any source of ignition anywhere near it. An 'empty' tank is essentially an
unexploded bomb.


Saw the answer to that on Scrapheap Challenge the other day - they were
making a diving helmet from an old Calor cylinder, and needed to cut it in
half.

So they filled it with water first.

That would work for cutting it, but the thermal mass when filled with
water would make it impossible to braze or solder.

I have heard of exhaust gasses fed into a tank being used to prevent
ignition. Perhaps another way might be to leave the cap off, fix the
tank down then deliberately ignite the internal gasses from a safe
distance?

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

Andy Champ wrote:
Spamlet wrote:

If the finish is not important, or you are able to repaint it
yourself, and the metal is not too far gone, you should be able to
have it brazed (especially true if it is just the 'usual' cracking
around the tap spigot). If it's just the seam that is weeping you
might even be able to heat the whole thing up and run some solder down
the seam inside. BUT DO make absolutely sure there is no smell of
petrol from the tank before you get any source of ignition anywhere
near it. An 'empty' tank is essentially an unexploded bomb.


Saw the answer to that on Scrapheap Challenge the other day - they were
making a diving helmet from an old Calor cylinder, and needed to cut it
in half.

So they filled it with water first.


take the top off and put in on the fire first. That will clear any petrol..


Andy

Spamlet wrote:
"Steve W" wrote in message
...
I'm fixing up a 1964 Qualcast Commodore cylinder lawnmower. Great success
yesterday, and managed to give my lawn its first decent cut for years!

However, the steel petrol tank is corroded and is leaking at the bottom.
I have dried it out, given it a few bashes, and shaken out quite a lot of
scale. What should I do next? My thoughts are one of the following:

- Pour in a two part resin mix, enough to cover / coat the bottom of the
tank, where the corrosion has been. I suppose I could use either epoxy
(expensive) or polyester (cheaper).

- Bare the outside of the tank and coat with one of the above resins (with
fibreglass matting?).

- Apply petropatch or similar proprietary patch on outside.

Any advice, please?

Thanks
Steve

You don't say whether you want to preserve the finish on the tank as a
restoration for show, or just to use?

If the finish is not important, or you are able to repaint it yourself, and
the metal is not too far gone, you should be able to have it brazed
(especially true if it is just the 'usual' cracking around the tap spigot).
If it's just the seam that is weeping you might even be able to heat the
whole thing up and run some solder down the seam inside. BUT DO make
absolutely sure there is no smell of petrol from the tank before you get any
source of ignition anywhere near it. An 'empty' tank is essentially an
unexploded bomb.

If the metal is too far gone, I would imagine that 'internal solutions' are
more likely to keep any holes filled than external. You might even be able
to line the tank with some kind of 'bag' if you were just looking to it as a
supporting structure. Wonder if one of those shiny wine/cider bags from
inside the cartons might be coaxed into service...

Dangerous mucking about with petrol though...

Steam cleaning it internally is the recommended method - I'm not sure
whether a domestic wallpaper steamer is up to the job.

Alternatively there are internal sealers that are used to repair petrol
tanks on cars. Try asking on uk.rec.cars.classic.

dan

On 15 Jul, 09:10, Dan Smithers wrote:
Spamlet wrote:
"Steve W" wrote in message
m...
I'm fixing up a 1964 Qualcast Commodore cylinder lawnmower. *Great success
yesterday, and managed to give my lawn its first decent cut for years!

snip

This was asked here last season. A couple of points which came up
then which haven't come up this time..............

If you use any kind of plastics, they could be affected by the petrol
and then block the fuel system in the mover (the poster spoke from
bitter experience).

One suggestion was to get some kind of metal drinks bottle such as
those used by hikers etc and convert it into a petrol tank.

HTH

wrote in message
...
On 15 Jul, 09:10, Dan Smithers wrote:
Spamlet wrote:
"Steve W" wrote in message
m...
I'm fixing up a 1964 Qualcast Commodore cylinder lawnmower. Great
success
yesterday, and managed to give my lawn its first decent cut for years!

snip

This was asked here last season. A couple of points which came up
then which haven't come up this time..............

If you use any kind of plastics, they could be affected by the petrol
and then block the fuel system in the mover (the poster spoke from
bitter experience).

One suggestion was to get some kind of metal drinks bottle such as
those used by hikers etc and convert it into a petrol tank.

HTH

Yes, jelly in the carb jets is no fun at all!

S

Harry Bloomfield wrote:
Andy Champ wrote :


So they filled it with water first.

That would work for cutting it, but the thermal mass when filled with
water would make it impossible to braze or solder.

Indeed. I was a little surprised to see them using what seemed to be an
electric cutter (thinks - in uk.d-i-y - must have been an angle
grinder!) with all that water.

But I bet the water displaces all the petrol vapour!

I have heard of exhaust gasses fed into a tank being used to prevent
ignition.

Like that idea. But be sure you've got enough vapour out.

Perhaps another way might be to leave the cap off, fix the
tank down then deliberately ignite the internal gasses from a safe
distance?


Even if it works, you might distort the tank.

Andy

In message
,
writes
One suggestion was to get some kind of metal drinks bottle such as
those used by hikers etc and convert it into a petrol tank.
Hmm, seem to remember the camping guys carry their liquid fuel in dinky
anodised aluminium bottles as well, trangia, primus and coleman all make
them IIRC along with a heap of 'generic' ones from places like
Decathlon. Ideal for conversion.
HTH

--
Clint Sharp