AJS & Matchless Owners Club

robcurrie wrote:Some hard plastic trim in my car had a "soft touch" black rubbery coating which became sticky after about 10 years. I managed to remove this with thinners followed by soap and water, but I would NOT RECOMMEND this on a plastic helmet. Best to replace the helmet (and get one with a gloss surface which is safer if you have the unfortunate incidence of surfing headfirst on tar).

Rob C

Certainly not use thinners or solvent on plastics Rob, most will attack certain types of plastics. I worked with plastics and had returns from unhappy customers returning goods that have been cleaned with something that had attacked them. The plastics being mainly Styrene and Acrylic. Clear Acrylic in particular that had flame polished edges, which stresses the material. It only has to smell a solvent and many little cracks will appear. The only way to stop this is diamond polish edges. This adds to costs, also machines I have worked on will only accept single flat panels. Had to be careful then with cutters costing £600. With that in mind, if you want to repair / stick styrene or acrylic, paint stripper will. It will soften and like weld it together. Needs time to harden.

clive wrote:If the surface has degraded perhaps you ought to replace it.

I'd second that.

Was it an "economy" priced product? If so, it's probably no great loss and the thing it's protecting is worthy of something better.

If it was an expensive product, perhaps get on to the manufacturer and make some enquiries? It'll be out of guarentee but worth seeing what they might have to say.

Alan

I would agree with replacing. I am sure I have seen warnings on helmets referring to painting, applying stickers etc. which could be harmful to the helmet. Something harmful seems to have got at yours.

Rob Harknett wrote:I would agree with replacing. I am sure I have seen warnings on helmets referring to painting, applying stickers etc. which could be harmful to the helmet. Something harmful seems to have got at yours.

No nothing harmful, apart from sunlight, which I now suspect may be the cause. I would certainly never use any kind of solvent on a helmet.

To put things in perspective, what was a matte finish is now a slightly sticky finish, a bit how a table feels when coke has been spilled on it. It is a thin layer that can be scratched through with a fingernail. I don't think it would cause any additional problems if I were sliding up the road on my ear.

So I think I'll just live with it for a while. Thanks for all the suggestions.

Interesting... some of my button switches (matt black) on my Citroen car have developed a sticky surface, tried white spirit on one and it is now a white button?? left the others alone

Are you sure it will be white underneath ? This happened to my helmet, ten years old but only used a few times. I cleaned it all off with kitchen spray. It is now a shiny black and I like it much better.
Stan

Could it be that the plastic moulding was shiny when it came out of the mould and they gave it a coating of matte lacquer to achieve the desired finish. Maybe it's that lacquer that has 'gone off'?

Hi All,
We suffer this phenomenon out here. First noticed it on the trinket tray in the car center console. If parked outside in the summer, the black plastic tray liner becomes extremely tacky and takes on a really glossy, wet look. Once cooled down, it looks matt finished and after a few years of this, it is cracking up and breaking away.

It seems to be temperature related but now we're feeling some tackiness on the TV remote cases indoors!

Curious.......is it only black items that suffer from it?

Hi Poplargreg

What make of helmet is it? I have a matt black HJC open faced helmet, though only for the last couple of months. So far it's OK, but it's something to keep an eye open for.

Malc

Hi

I've been annoyed by this phenomena on a Roksan remote control for a while now, (it's just on the black rubbery matt surface). Decided to 'have a go at it' prompted by this question.

The sticky coating was fairly easily removed with a kitchen wipe and methylated spirit, it has left the surface more shiny than before so I conclude it was the surface finish that had degraded, probably due to exposure to UV, the remote was found upside down on a window sill.

The meths has removed the coating and I'm left with a semi matt surface.

If you decide it's worth having a go with meths or de-natured alcohol, (which will more than likely remove the sticky surface), be prepared for a change in surface finish.

Regards Mick