MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Silicone

How does one deal with silicone contamination on paintwork?
As an aside to reassembling my Frog I decided I wasn't quite happy with the paint finish on the n/s inner wing, so I sanded it back with W&D and gave it a coat of primer, flatted and sprayed a top coat.
The top coat immediately puckered up into mini crevasses and fish eyes. :-((

I wiped it over carefully with panel wipe, washed it with soapy water, and reflatted it, dried it, and panel-wiped it again. But when I primed it this time it again formed mandlebrot patterns only now they are finer but spread over the whole area so I have clearly spread the contamination rather than removing it!

I have no idea where the silicone has come from but that is clearly what it is. Any proper suggestions on how to deal with this. Its an annoying distraction at this stage.
GuyW

Guy,
What sort of silicone do you think its is - silicone sealant type stuff?

if so you can get silicone sealant remover (I'm looking at a unibond tube from B&Q or there a brush on one https://www.housemakers.co.uk/silicon-seal-remover.html?gclid=EAIaIQobChMIjseZ1dfU2AIVz5TtCh3ffQsqEAQYCyABEgL0I_D_BwE

those could leave quick a sticky residue though so you'd want lots of panel wipe to take that off

tim
timmyk

Silicon is present in a lot of polishes now - back to black etc. You will have to be far more aggressive than soap and water I am afraid. Thinners may move it.
David k Brenchley

I confess to never having heard of mandlebrot patterns so found a Wikipedia article that rapidly became mathematically complex!

When you read about silicone removal it's said to be virtually impossible to completely remove it and yet many polishes contain silicone! I did some paint repairs on the V70 doors last year (with aerosols) and used wet and dry plus panel wipe to prepare them. The paint seems ok. I don't have an answer other than doing what you've already tried or taking it back to bare metal which you probably don't want to do. But I'm interested in other comments on this as it potentially affects all of us.
Bill Bretherton

I had a bit of a google - silicone sealant and silicone brake fluid are basically the same thing (the sealant is just the polymer of the ingredient in the brake fluid) - its also what goes into polishes and some medicines, hair products etc etc.

Downside is that water alcohols and acetone won't touch it, but the silicone seal removers should.

The other thing that looks like it would is cellosolve - if that's the paint you're using (seem to remember it was) then that's potentially the solution.

If you've any cellosolve thinners they would probably clean it up - certainly worth a try if you can't get the remover

As Bill says though let us know how it goes - it's a bit of guesswork and might be paint related - depends how the solvent in the paint affects the silicone, it might just sit on top of it, or it might dissolve into it and make it swell
timmyk

If you go to your paint shop they should have silicone remover
Make sure you are using good clean cloths, any polish on the cloth will do it big time
Just use a nice clean cloth and get it nice and wet with the silicone remover and give it a good wipeover and let it dry off then hit it with the paint of choice
Here ,the best one's called "Prepsol" Grease + Wax remover
or another is Siliconoff
both runny liquid like thinners

Thinners won't do it, but, if you arn't able to get silicone remover I have had a bit of luck by soaking a clean cloth in clean petrol and giving the panel a good wipeover with that, but keep the heaters away till it dries right off
willy
William Revit

i know a few years back we had trouble at work with paint on the aircraft and silicon and one of he problems was people wearing the wrist bands that various charities sold made out of silicon rubber they were banned from being worn near the aircraft which seemed to ease the problem a bit .
mark heyworth

WD40 attacks and removes silicone - I've used it to remove old silicone in a shower cubicle - you'd then have to ensure the WD40 was removed of course...although I'd have thought panel wipe/thinners would clear it away.
Jeremy MkIII

Jeremy, WD40 seems to soften silicone (say to remove it from a shower) as does acetone but doesn't actually dissolve it i.e. they're not specific silicone solvents AIUI. Reading around the interweb it seems the only true silicone solvent is "sulfonic" acid.

But then, paint shops are preparing previously polished cars everyday for painting (with 2 pack) so it can't be that hard you'd think. Cellulose does seem quite "fussy" in that the solvents in it readily react with other materials.
Bill Bretherton

Thanks for the responses so far. Seems its a bit of a problem!
My suspicion is that it is silicone (the synhetic material, not Silicon which is a naturally occuring mineral). Before applying the first coat of primer I wiped it down with a folded soft tissue dipped in Panel wipe, using the two pad system, one wet, one dry, long overlapping strokes across the panel. The tissue I picked up off the workbench, thinking it was what I had folded ready for use. But given the reaction I am now getting it is possible - even likely - that the tissue that I picked up was what my son had just discarded after treating his AM windscreen with . . . . Rainex!

I don't know what the active ingredients in Rainex are, but given the effect it has on raindrops I would say that it is liquid silicone. Its certainly not what one would intentionally use as a prep for paint spraying!

Mandlebrot graphic:



GuyW

RainX's main ingredient according to Wiki, is polysiloxanes.
This link explains what that means to those of us who are not chemists
http://en.wikipedia.org/wiki/Silicone
The last word in the link says it all.
Several theories to remove RainX - diluted vinegar, cellulose thinners (obviously a non starter!), extremely fine wire wool, soda crystals and finally toothpaste - you may need a lot for a wing though.
Jeremy MkIII

I guess this is what I need
http://tinyurl.com/ycoos6sd




GuyW

Interesting comment about Rainex. I used their antimist on the inside of my wife's car - it's awful! It doesn't stop the condensation only makes it impossible to wipe away. I have tried a number of common household material (turps, meths, acetone, spit(!), car window cleaner) none of which will take it away. Emails to manufacturer are just ignored. Hadn't tried wd40 - will try that next.
Graeme Williams

Graeme,
glass cutting polish gets Rain-X repellent off (the outside) so you could try that.
Nigel Atkins

Agree with Graeme. I did the exact same thing with my wife's car, with the exact same results. Not a fan of Rainex.

On my campervan I just gave the glass a severe clean with meths because it was filthy when I got it. For some reason it seems to resist misting - not completely but it's easy to wipe away now.
Greybeard

I'm not a fan of Rain-X anti-mist stuff, only tried it once and found it didn't work, I also possess (synthetic) chamois, kept moist, and wind-down windows.

But I'm a fan of Rain-X or equivalent for the exterior glass (including headlights) mainly because it makes them easier to clean. The windscreens on Spridgets are too upright for them to readily clear of rain with Rain-X or equivalent.
Nigel Atkins

I've seen before people moaning about not being able to get Rain-X (outside repellent) off their windscreen and just can't imagine what they done to get into that situation as I've used it excessively (put too much on each time) for decades and have had no problems.

After I've done the washing up I might go to my shed, trying to get the "vintage" digital camera to cooperate and put up a photo of a possible solution.
Nigel Atkins

unless you're going very quickly....

I'd heard WD40 had some silicone in it. The only way I got rid of pinholes and fisheyes was to sand it off and try again. I found halfords hi build primer in a can to be very resistive to it, so much so I did the whole P6 in it before getting on with the 'proper' primer.
Rob Armstrong

Rainex works very well, at least the external version does. At M-way speeds you can drive in heavy rain without even using the wipers at all - the water forms droplets which get rapidly swept away by the wind at that speed. Not quite so well at lower speeds, but still works well enough for clear vision. I have never tried their anti-mist version. In fact I didn't know they dd one.

Rainex is not very good as a pre-paint panel wipe.

Rob, that "mandlebrot" photo is Halfords High Build primer. And that was after wet sanding and washing down. Unfortunately that just seems to spread the contamination!
GuyW

Rob,
I'm surprised you bother with a nannying windscreen.
Nigel Atkins

Graeme,
to save me bullying my elderly camera into use I thought I'd put a link up but it looks like they no longer sell Halfords Intensive Glass Cutter anymore, well I've probably had the bottle a few years as you use very little each time.

I'm sure some other intensive glass cutters would probably be as good, or near enough, as Halfords didn't make the stuff. It's a liquid polish.

As always it seems like this was good stuff and now it's gone -

BUT

- if you want to swing by I'll apply a little to your windscreen, careful not to drip any on the interior, for wastage and care of the interior, and I'll rent its use to you for a small weekly charge - cos I'm good that way.

PS Please don't bring the Kent "lads" to my doorstep tho'.
Nigel Atkins

The usual stuff used for final polishing of glass these days is cerium oxide. There are a number of people selling it on ebay.
David Billington

Glass polish (and cerium oxide) seems a bit extreme. I'll try phoning Rainex contacts again. Trying to reach the inside of the windscreen on a modern car is actually quite backbreaking. THe irony is I only applied the stuff to the driver's side - now the passenger side is the one that's clear of condensation. On the driver's the water + antimist form what looks like transluscent jam. It spreads but won't wipe off.
Graeme Williams

Graeme,
glass polish won't be extreme, and occasional use far from it. Don't let the names put you off, they don't contain shards of diamonds that'll score the screen.

The Halfords Intensive Glass Cutter is design to thoroughly clean without scratching and - "is recommended for use before applying Halfords Rain Repellent."

That’s a point; did you thoroughly clean the inside of the windscreen before applying the anti-mist? Not that it matters now as you should be able to clean everything off.

For the Rain –X Repellent they suggest on the outside using something like Cif (Jiff to us oldies).

From Rain-X Anti-fog Safety Sheet
. propan-2-ol, isopropyl alcohol, isopropanol
. 2-butoxyethanol, ethylene glycol monobutyl ether, butyl cellosolve

Kraco Car Care International ltd.
Grosvenor House, 20 Barrington Road
WA14 1HB Altrincham - United Kingdom
T +44 (0)161-927-7000
KCCI-orders@kraco.com - www.kraco.com

If you can’t get anywhere there try contacting the British bloke in America with the (probably self-given) title of “Senior Vice President Of Sales” (no less!), it seems to be his company.
Nigel Atkins

i am only self taught on painting and spraying etc, so would advise that you should you have used a compressor to spray the paint, then this will have sucked in the already contaminated air. You may want to think about draining your receiver, and lines, and water trap if you have one, and the air filter on the machine.
If already done, ignore me, just thinking out loud.
P Bentley

Rob,

WD40 doesn't contain silicone, see
http://www.wd40.com/faqs

Didn't know the RainX interior was so poor as I'm a fan of the exterior stuff. Any speed over 30 and the rain runs off, excellent stuff.
Jeremy MkIII

No, PB Fortunately I wasn't using spray equipment, just a rattle can. And only at this stage doing that small area along the topp and inner suface of the inner wheel arch, so the problem should be reasonably well contained.

I am aim to call at a bodyshop to get advice. Problem is the local town no longer has a paint materials supplier and the local bodyshops all buy direct, so I am hoping someone will let me have soething from their own stocks.
GuyW

Guy if you don't have any luck, I am going to inspect my car this week that's in the body shop, I will get you some if you cant get any,


Andy Tilney

Thanks Andy. Which body shop are you using?
GuyW

I dont know if anyone is still interested in the original topic on how to deal with silicone contamination? A local, good bodyshop said it's difficult to remove, but to try white spirit or celly thinners, then wash down with soapy water, then rinse with clean water then panel wipe.

But very surprisingly another thing they do is to polish with a silicone car liquid wax and immediately clean it off with degreaser! As the car wax includes silicone solvents to make it liquid, the theory is this dissolves the silicone contaminant already on the panel and one can then remove the wax together with the dissolved silicone with degreaser. Sounds high risk but apparently it works !
GuyW

Guy, did you get your blue rattlecan off a shelf? I cannot get cherry red anywhere. (please note the deep sympathy for your trouble)
Nick and Cherry Scoop

Guy I always use Longlane in Dalton, have known them over 25 years, they have made a fantastic of my B
Andy Tilney

Hi Nick,
I bought my Iris Blue paint (AKA Isis Blue or Irish Blue, depending on the reading skills of the person printing out the label) from Jawel Paints and got them to make me up 3 rattle cans at the same time. The intention was to have it for touch ups in the future, but at the rate I am going with this paint problem I will have used it all up long before then!
GuyW

Nigel: thanks for the information. Rain-X must use this bbs because today I got a Tweet from them suggestion their "Rain-x X-treme clean" was designed to remove their products. I did tweet them 3 weeks ago. Great..... until you try to buy it in the UK. No-one seems to have it, atleast, not the x-treme version of the cleaner. I can get it from Wallmart.... now where's the nearest?
Graeme Williams

The UK equivalent of Walmart is ASDA.

This is their offering

https://groceries.asda.com/search/%22rain%20x%22

Probably need to C&P
Dave O'Neill 2

Oh, I see it's added a few extras in there.

I particularly like the Rita Ora nail varnish!
Dave O'Neill 2

Thanks Guy. I feared it might not have been off the shelf.
Nick and Cherry Scoop

Graeme,
(I like this double tracking)
why not just try some Cif, on a trial area at least.

Whilst in the kitchen borrow a plastic spatula, with an offset head if available, then you can put the cloth with Cif on the back it's head to get into the windscreen crevice if the trial works. Use a small piece of cloth for this or only have the Cif on the part that rests against the spatula head otherwise you get Cif overwipe everywhere and have to clean that up entering a never ending cycle.

A long handled wooden spoon is also a useful cleaning. Either clean and replace and no one need be the wiser or have cast offs for your cleaning stock you'll be surprised how often perfectly usable kitchen items "have" to be replaced by the boss.
Nigel Atkins

Guy. I can't offer much help as you are using rattle cans, but if the problem occurs when you are painting with a spray gun, you can get a little bottle (about the size of a nail varnish bottle) of silicone inhibitor from your paint supplier. You put in just two or three drops into the paint already in the pot and it usually works, particularly with Celly.

But,if you can flat back what you have put on, wipe it with panel wipe using the two cloth method you mentioned, then leave it to "breathe" for 24hrs, give it a wipe with dry tack cloth, then apply several very light coats (dusting it on) of both primer, (it may be advisable to let the primer breathe again after you've flatted it) and top coats, observing flash off times between coats.

It can be difficult with an aerosol, but you can achieve it by applying from a bit further away. When finished it may appear a bit "dry" so you you will have to flat and Polish it.

Paint can react for no apparent reason, even though there will be one, and can be a PITA.

My Valeter friend will not book a car in that is in a paint shop for repairs until the car is out of the paint shop and clear of paint reaction problems. He speaks from bitter experience of time wasted and cars not turning up.

Bernie.
b higginson

The photo you showed is typical of shearing. This happens when a faster drying topcoat shrinks on a still soft primer coat. A case of too much and too quickly before the solvents underneath have evaporated. Temperature is always a big factor too so mid winter and cold garage are not helping. Cellulose likes to be painted between 18 to 25 degrees, AND with 40 and 50% humidity. If you paint outside these figures and the substrate (the car) is cold, shearing will usually happen. Unless you have access to a heated booth your best shot may be to take off the crazed paint (you'll have to anyway) and flat the original topcoat with 1000/1200 and polish from there. If you are still painting it's a good idea to get a thermometer/barometer and hang it near to the car.
f pollock

Thanks Fergus
The yellow is an acrylic high build primer, over a 2-pack top coat that had been well flatted with 280 grit W&D. The high build was intended to fill some minor imperfections that l wasn't happy with. The underlying coat was done about 2 months ago.

This is all a bit of a distraction at this stage. I am not going for a perfect finish as it is only the inner wing, but l wasn't happy with the underlying 2K that still showed some slight brush marks.

The plan is to leave the proper paint job on the external bodywork until later in the year when l can expect better conditions. This is just so l can progress with other under bonnet assembly in the next couple of months.
GuyW

(Boring) update on removing Rainex Anti Mist. Having been told by Rainex to buy their super cleaner, this is the twitter conversation:

RAINEX: Hi Graeme! We recommend our Rain-X X-treme Clean (sold in Walmart under the wiper blades) or Soft Scrub. Best, Rain-X

ME: Can't find it in the UK

RAINEX: Hi Graeme! Unfortunately, we do not sell the Rain-X X-treme Clean in the UK and we can't speak for Soft Scrub as that is not our product. We wish you the best in resolving your issue. Best, Rain-X

Ah, customer service. Love the last line which translates as "Best of luck mate, we don't know the hell you get it off either"

Might try removing it with the Rita Ora nail varnish - can't make the windscreen any less clear.
Graeme Williams

Its called Globalisation, Graeme. Just expect to be kicked in the globalls
GuyW

Graeme,
could that be the joy of a British person now in the USA mentally leaving behind those he's er, left behind.

Try Cif as they suggest for preparation for Rain-X Repellent -
"It is essential to observe the directions for use. In particular:

Before application, ensure the screen is thoroughly cleaned. In particular, remove all waxes and silicones that may have been applied if the car has been through a car wash. This is best achieved with a soft abrasive cleaner, such as Cif."

http://www.rainx.co.uk/tips-and-info/

Cif is a Unilever product, they also offer simple cleaning solutions that don't always involve using their products.

https://www.cleanipedia.com/gb

And of course it used to be Jif not Jiff.
Nigel Atkins

An update....
I've had SOME success, not perfect but encouraging, with meths and a tesco brand non-scratch (yellow) pot scourer. But I had to scrub very hard. It's hard work and the car stinks but happily it's her car not mine! I'll keep trying.
Greybeard

try a petrol wash down and dry off
William Revit

Is this now advice for removing Rain-ex anti mist from windscreens or silicone contamination prior to painting?
GuyW

Your insomnia is getting beyond a joke, Guy!
Nick and Cherry Scoop

No excuse last night. Just the norm for me - always has been. Only thing I could ever claim to have in common with Maggie T. My children used to complain that I was hyperactive!
GuyW

petrol suggestion was for silicone
William Revit

Thanks Willie, I haven't tried that one.

Latest attempt is it has been washed down with white spirit which is what the bodyshop suggested, followed by soapy water then clear water, then wet sanded and rinse. It is now drying ready for another go with a different, light primer coat. All this because I wasn't happy with a few minor brush marks in the colour coat!

I will report back!
GuyW

I would imagine white spirits would give a similar result to petrol
Probably a bit late now ,but only use white spirits in ventilated areas and keep the stuff off your skin as much as possible
Used to use it for cleaning bike parts but ended up with a nasty rash on my hands and arms that took ages to get rid of
willy
William Revit

Guy, silicone and painting can be a nightmare. I've been caught out a few times painting Sprites and bike frames. Mixing paint with syringes was my first stupid error. Since then I've been more aware but nitrile gloves caught me out again yesterday, some brands seem to use silicone in manufacture.
I usually clean everything over with Lechler silicone remover after the panel wipe now.

Yesterday was a jinxed painting day, as after the silicone episode the base coat mysteriously decided not to adhere to the primer properly. I hate painting.
P Simpson

Hi Paul
I called in at Autobodies on the Shap road estate and they said to wash down with white spirit, then soapy water. It does seem to have worked (at the 4th attempt) as l now have a decent primer layer with no sign of it misbehaving. But l am yet to try the top colour coat !
You painting at this time of the year too? !!
GuyW

Yes it's not an ideal time as it's too cold, but I have sorted an extraction system, air fed breathing supply, and bake oven for the bike frames. Unfortunately it doesn't fit a Sprite or a Sprite hardtop which was the last job.

Painting is a difficult skill to master, I've only moved from unconscious incompetence towards conscious incompetence so far :)
P Simpson

I'm also tackling my first bit of spraying in around 30 years!

That's an interesting comment about Nitrile gloves P. Etch primer and primer filler have gone on OK so far with gloves in use but I'll bear your comment in mind when I get on to the top coat.

I'm working on a door which I've taken off to work on in the shed. The 'spray booth' is formed by screening off a zone in the shed with left-over damp proof membrane. Before I start work I warm the shed up a bit with an oil-filled electric radiator. I've borrowed a heat lamp from the dog's kennel and that has done a good job of baking the primer so that I have been able to spray several coats in an afternoon.

Colin
C Mee

Interesting on this
A workshop I was at years ago had heaps of trouble with fisheyes in the paint, It was a propper sealed spray booth with air supply filters and all--------
It turned out to be caused by the used car yard next door were using tyre shine spray on their used cars and the, what must have been a very small amount of overspray mist from the tyre shine was getting into the air duct for the spraybooth and through the filters
Wonderfull stuff silicone--------
William Revit

This thread was discussed between 13/01/2018 and 24/01/2018

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.