MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

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 MGA - Finishing Strip

The two finishing strips on my car have now bubbled up very badly after 16 years - see photo. The metal (aluminium) is very sound. It looks like the etch primer and two pack undercoat have turned to dust underneath the two pack top coat. Perhaps a chemical reaction with the aluminium? What advice does anyone have about repainting? Do I need some sort of barrier coat before the undercoat. I have not had anything similar happen with the main aluminium panels which were painted in the same way.

Steve

Steve Gyles

Hi Steve,
I would bite the bullet and replace the two strips - Moss ones are actually pretty good now - i just bought a pair. U-Pol etch primer first then colour coat. I also prepainted the square top of the fastener and some of the thread before sliding it into the finishing strip then painted the washer and nut on the inside of the sill once in place. If you refurb the exisiting, then a good run over with a finishing sander before U-Pol primer and colour.

regards
Colin
Colin Manley

Thanks Colin

As it happens, after posting this thread, I managed to break one of the strips, so perhaps they had weakened more than I thought. Will follow-up on your advice. Where do I source U-Pol?

Looks like a late Autumn job. More important things at the moment such as preparing my Tornado presentation for you!

Steve
Steve Gyles

Steve, I used zinc chromate primer on mine, followed by some sandable primer, then brushed on the body top coat of acrylic enamel. Fingers crossed.
I think zinc chromate was used originally on the aluminium parts.
Art Pearse

Steve,
I managed to find it in a bigger store of Halfords - it's dearer than standard primer but far more effective. Its in a maroonish colour 500ml can with a grey cap.

regards
Colin
Colin Manley

Zinc Chromate is no longer available. Has been replaced by zinc oxide. You can buy it in rattle cans from any aircraft supply.
C.R. Tyrell

I can also recommend the U-pol
http://www.ebay.co.uk/itm/U-pol-Acid-8-Etch-Primer-Aerosol-450ml-/291234194444?pt=UK_Body_Shop_Supplies_Paint&hash=item43cee9240c

I use the spray gun and an epoxy etch for the bulk of stuff, but this is great for small jobs.

I did have a problem with an (epoxy) etch primer in the past, with poor adhesion. Maybe that could have been the problem with your strips?
Neil MG

Thanks Neil. Ordered.

Steve
Steve Gyles

I got my zinc chromate from Canadian Tire, spray can, yellow top.
Art Pearse

Zinc Chromate primer is still widely available like this:
http://www.ebay.com/itm/191210840031

I re-did my aluminum sill trim strips in spring of 2008. I used a right angle die grinder with 2-inch Scotchbrite disc to remove all the old paint and polish it up. Washed it down with lacquer thinner to be perfectly clean. Let dry, and sprayed it with zinc chromate primer. I then sprayed it with same paint I use on the body, acrylic enamel with catalyzing hardener and didn't bother with any further finishing.

Six years and 48,000 miles later the paint on the trim strips is still in tact with no chipping, which is pretty amazing considering the roads I drive on.

Barney Gaylord

Thanks Barney. I now have both strips removed. The rest of the body work under the strips is in pristine condition fortunately. The new strips from Moss do not come cheap! They should arrive in the next day or two.

Thinking back to my rebuild I did all the panel painting at evening classes using the specialist painting facilities and ovens. This included the etch primer which they supplied, although I supplied the undercoat and top coat. However, it is most probable that I did the strips at home which did not include the etch primer. Lesson there I guess.

Steve
Steve Gyles

I have never had finishing strips. I assume they cover the join between the sills and body at the bottom of the car, and run from wheel arch to wheel arch.
Nigel Munford

Nigel

Correct. They will cost you about £45 incl delivery from Moss. The kit includes the fixings. You will of course then need to paint them body colour.

If you look along the bottom of the sill there should be about 4 vacant holes, unless you have new sills that have never been drilled. But there should be holes at the bottom of both the front and rear wings. They simply tidy up the 'ragged?' bottom edge and the panel joints.

Steve
Steve Gyles

Strips and U-Pol arrived. I have already applied the U-Pol, drying as I type. I got the impression from Barney's write-up above that he put his top coat straight on top of the etch primer? Is this ok or should I put an undercoat on first?

Steve
Steve Gyles

I left mine unfinished aluminum. Unchanged in 20 years. Car color is dove grey so they blend well.

Good luck

Ted
Ted Persons

Steve,
You can put the colour coat directly onto the U Pol. As usual, a few light coats to get the depth, then a heavy gloss coat.

regards
Colin
Colin Manley

Interestingly no-one has mentioned Bob West's view (so I will!) that it's safer not to use these strips for fear of promoting corrosion over time. That's what he recommended to me and I have followed it, although I note Steve's comment that he has not suffered any corrosion, so maybe it's OK with careful preparation before fitting.
Bruce.
Bruce Mayo

Bruce

I seem to remember Bob saying that to me many years ago but I went ahead anyway. I was actually quite surprised how relatively clean and clear of muck it all was behind the strips. I was fearing the worst with all that apparent corrosion.

Steve
Steve Gyles

I agree with Bob's advice and don't have the finishing strip fitted.

Lower wings are held in place with stainless fittings and I undo the bottom of the sill and remove the splash panels each year to clean inside.

To many memories of corroded lower wings in the British climate with its added seasonal salt.
John Bray

I have the strips fitted, and when I had to remove them to have a wing repaired, there was no crud or corrosion behind them. They have been on for at least ten years.
dominic clancy

This thread was discussed between 21/09/2014 and 24/09/2014

MG MGA index

This thread is from the archives. Join the live MG MGA BBS now