Hammerite "rust beater"

[TiggerToo]

Does it "go off"?
I have a tin which is a few years old. The solids have sedimented, but it is still workable, and the solids can be gotten back into suspension after some patient stirring.

Will it still work to "convert" rust?

 

[penberth3]

Take the chance it's no good, or bin it and spend a few pounds on some fresh stuff. I know what I'd do.

 

[TiggerToo]

That is probably what I will do, but I am curious nevertheless.

Does anyone KNOW whether there is a "shelf life" to the rust-beating chemistry, as opposed to the "paint chemistry"?

 

[JimC]

BTW of all the rust treatments I applied to my cast iron keels over the years I found Hammerite No1 Rust Beater the most effective.

 

[penberth3]

That is probably what I will do, but I am curious nevertheless.

Does anyone KNOW whether there is a "shelf life" to the rust-beating chemistry, as opposed to the "paint chemistry"?

The manufacturer should give a shelf life/open time on their data sheet. Life may reduced depending on storage conditions.

 

[JumbleDuck]

Does it "go off"?
I have a tin which is a few years old. The solids have sedimented, but it is still workable, and the solids can be gotten back into suspension after some patient stirring.

I've just used some from a tin which I bought in 1989, when it was still "Finnegan's No. 1". It needed a good old stir to get it to the usual consistency, but looked, smelt and felt just as it should.

 

[JumbleDuck]

The manufacturer should give a shelf life/open time on their data sheet. Life may reduced depending on storage conditions.

Two years unopened. And it's not for use underwater, by the way. See attached.

It may be relevant that the paint chemistry has clearly changed a lot. Hammerite thinners are now white spirit whereas they used to be xylene based and neither will work the wrong way round. Luckily International Thinners No. 3 (the stuff for antifouling) are also xylene based and work fairly well with old Hammerite products.

 

[JimC]

... And it's not for use underwater, by the way. ...

I overcoated it with Primocon before antifouling and experienced no probs. When I stripped my keels last year using a Tercoo rotary blaster the No1 Rustbeater took a lot of shifting. It seemed to have bonded itself and the underlying rust hard onto the base metal.

 

[Jim@sea]

Two years unopened. And it's not for use underwater, by the way. See attached.

It may be relevant that the paint chemistry has clearly changed a lot. Hammerite thinners are now white spirit whereas they used to be xylene based and neither will work the wrong way round. Luckily International Thinners No. 3 (the stuff for antifouling) are also xylene based and work fairly well with old Hammerite products.

I always use Acetone for thinning Hammerite.

 

[Caraway]

If acetone or petrol won't work the coatings product is probably rubbish anyway.

 

[Gary Fox]

I would stir it with a drill stirrer, and use it.

 

[RichardS]

I always use Acetone for thinning Hammerite.

I used to use acetone with the old formulation which was Elf 'n Safety-ied off the shelves. White spirit is fine for the 21st Century rubbish version.

Richard

 

[Spirit (of Glenans)]

Give it a stir and try it out on any rusty piece of steel. If it doesn't convert the rust into substrate for your paint system then dispose of it (responsibly, at a municipal facility, rather than "binning it", which is the usual advice here).