Porsche 356A Horn Button - Restoration

[mrg3.6]

My 356A horn button is generally in good condition however as seems common it is crazed on the surface.

Reading a few threads on the 356 forum as well as the following photographs on http://www.356garage.com.au/ it would seem that the crazing can be successfully removed by filling the crazing with superglue then sand/polish the surface:

You can make the old one with hairline cracks almost new yourself.

1. Flood cracks with cyanoacrylate (Crazy) glue. Make sure it is the water-thin variety. Let dry thoroughly, say overnight.
2. Sand with super fine paper--1800 or 2000 grit.
3 Buff with "plastic" medium (from Eastwood) and soft wheel, being super careful NOT to overheat the plastic horn button.







Just wondering if anyone had tried this?

Thx
Martin

[Hendrik Moulds]

Not tried it but be careful, they crack quite easily and nice ones are hard to come by (and therefore expensive).
The reproductions aren't great, or at least the ones I've seen.

[Winston Teague]

Why risk it? You have a 60 year old piece of your 60 year old car, surely it's allowed to wear its age with pride. It may well have decayed due to uv exposure, and nowadays lives in a garage, so that decay may have slowed, & who knows how long the superglue will last? It will only be original once.......

[roy mawbey]

Ah I take a different view, mine looks like new its the first thing I notice getting in the car, I see it all the time, to see a badly crazed piece of plastic would constantly annoy me. I have never replaced or modified hardly anything on my car, even my 60 year old carpets are original !

But that piece of plastic needs to look nice. If you are prepared to buy a copy if you mess up then why not try the repair first on one small specific area. The photos show a real difference. We are all different go with your thoughts but be fully aware the repair might well fail.

Roy

[mrg3.6]

Agree with Roy, I don't mind patina or wear'n'tear but the horn crazing plain isn't nice.

Martin

[vwgillybilly]

Really impressed by that.

Unfortunately the main enemy of a 356 horn push is people pushing folding the seat into it. My old one was way past repair, but the repro I bought is really really nice.

Gill

[TLC356]

While I have never used crazy glue but I have used lacquer thinner on knobs with good results. I suggest you experiment on a small section to see if it works. Other solvents may also be tried. Here are notes from the registry on the knob job.

The miracle product is laquer thinner. Take the knob and dip it in the thinner just for a couple seconds. Then take a clean rag dampened with the thinner, and rub the knob until you start to see the finish "come up". You'll quickly learn the feel for when you need to turn, and remoisten the rag, you'll feel it "drag" on the plastic, you'll probably have to rewet the rag two or three times before the finish starts getting real nice.

Remember, you're actually removing a film of plastic, so don't go crazy. When you get a finish that looks good, let it dry for a few seconds, then use a separate cloth, and buff. You can follow with a wax if you want, but probably won't need to.

It helps if you screw the knob onto a bolt, then secure the bolt in a vise. This way, you can buff the knob like a "shoe shiner".

My ivory knobs were extremely "checked", but came back beautifully.....and all six took less than 30 minutes.