Adding clearcoat to new frame.

[Dromen]

I just rec'd a new Italian steel frame. I have this unfounded opinion(based only on internet noise) that tho beautiful, most Italian bike paint systems are not so durable.

I'm meeting with a local painter who has done good work in the past to discuss spraying with some additional USA clear coat to toughen her up.

So my opinion can be slightly more 'founded', any thoughts or experiences with this process?

[David Kirk]

I suppose it can be done but I wonder how much value added it would be.

There are two ways clear coat will bond to the existing paint - mechanically and chemically. Typically clear is applied in the proper time frame so that it has a chemical bond to the underlying paint and if the clear is applied outside this ideal time frame then the chemical bond will not be what one would hope for.

There is also mechanical bonding - the painter will scuff up the existing paint to give it a tooth for the new paint to bond to and this can be effective but it will never end up behaving as a unit..........it will always be one layer on another.

One key thing to remember is that the chip resistance of the paint all comes down to the primer and base coats. If these aren't done properly nothing you do on top of it will give any substantial benefit to the chip resistance. So adding clear to substandard paint will not make it much more durable.......in fact some think that it can make it more prone to chipping as the whole thing gets thicker. Any way you cut it there is little benefit.

What do you fear about the new paint?

Dave

[Ahneida Ride]

I know little about paint ...

But Mr. Kirk is correct.

I understand the Clear Coat must be applied soon after paint to
be really effective.

Without heat it takes a day or two for the Clear Coat to dry.
It can take much longer to solidify.

[ultraman6970]

Clear is a simple job (if the guy knows what he is doing), the guy has to sand the whole bike like with 500 grit wet sand paper... clear it maybe with 2 or 3 coats of polyurethane, sand and polish. And then will last maybe several years intact.

Polyurethane dries chemically, if you are going to clear using crap rattle can form the store i would not even dare to clear with that because is plain crap and that paint will need air to dry and cure and that could take months. With polyurethane you might be able to put the bike together next day if you want, the polyurethane is ready for handling in one hour or less depending on the conditions, but in 12 hours is more than dry and ready for sanding and polishing.

Good luck.

[Pete Mckeon]

:banana:I suppose it can be done but I wonder how much value added it would be.

There are two ways clear coat will bond to the existing paint - mechanically and chemically. Typically clear is applied in the proper time frame so that it has a chemical bond to the underlying paint and if the clear is applied outside this ideal time frame then the chemical bond will not be what one would hope for.

There is also mechanical bonding - the painter will scuff up the existing paint to give it a tooth for the new paint to bond to and this can be effective but it will never end up behaving as a unit..........it will always be one layer on another.

One key thing to remember is that the chip resistance of the paint all comes down to the primer and base coats. If these aren't done properly nothing you do on top of it will give any substantial benefit to the chip resistance. So adding clear to substandard paint will not make it much more durable.......in fact some think that it can make it more prone to chipping as the whole thing gets thicker. Any way you cut it there is little benefit.

What do you fear about the new paint?

Dave

[d14vd_h]

If your really concerned about maintianing the longeivity of the frame paint and decals, 2 options I explored were,
Sourcing a replacement set of decals and tucking away for the inevitable respray years down the line with the 'patina' has built up significantly.
Second option, is to use a film much like you see on bumper protectors.
The issue with the film is that over time it cam become bonded to the paint/decals and potentially lift them on removal.

[Dave]

The idea that Italian paint jobs lack durability probably started way back in the 60's or before, when lacquer was used.

I bought a '95 Tomassini and had no problems at all with the paint's durability. Likewise, my Colnago's from '00 and '02 had durable paint. I know that is was a chemically hardened paint because lacquer thinner wouldn't bother the paint.

I would not assume a delicate paint problem and go to the bother and expense of adding additional clear coats. If you drop a wrench on the frame and get a chip in the paint, more clear coat would not make the paint more resistant to that type of damage.

[Columbus SLX]

The idea that Italian paint jobs lack durability probably started way back in the 60's or before, when lacquer was used.

I bought a '95 Tomassini and had no problems at all with the paint's durability. Likewise, my Colnago's from '00 and '02 had durable paint. I know that is was a chemically hardened paint because lacquer thinner wouldn't bother the paint.

I would not assume a delicate paint problem and go to the bother and expense of adding additional clear coats. If you drop a wrench on the frame and get a chip in the paint, more clear coat would not make the paint more resistant to that type of damage.

+1. Part of the poor durability of vintage Italian paint has to do with very thin coats and the fact many were chromed under the paint causing poor adhesion. If yours is a modern Italian frame I doubt you'll have the same issues.

A 2-part clear won't chemically dissolve the layer below regardless of scuffing. It'll be a mechanical bond which can unfortunately "delaminate" upon impact (wrench, rock, etc.). My dad and I had this problem once shooting a car - in addition to poor adhesion you could actually see the 1000 grit scuff marks of the last color coat, because the 2pk urethane didn't dissolve it! Total mess.

[Dromen]

Thank you all for the clear-ity. I have now idea where or when i heard Italian paint was fragile. Just have had too much time to think about the build and such since it was on back order for 3 months.

Now i have just enough knowledge on chemical and mechanical bonding of clearcoat and the fragility of pre-modern paint systems to be exciting in the local tavern now that hockey is over.

Mr. Kirk - to your question, this is a frame i have gazed at for too long. I final decided to dip in the pool. I have spent way too much time waffling over this and that on the build to make it 'my' perfect. Just want it to stay perfect for as long as possible. If my opinion on paint's lack of durability was 'founded', I just thought an extra layer or two would keep it perfect for a little longer. Once again, fixes/retrofits, etc typically create more problems than the original/new.

Thanks again. I think i will cancel the appointment with the painter.

[avalonracing]

Another option is to put clear tape of the especially chip prone spots and be careful with the rest. For example when I am working on my bike if the bars are not yet taped (or between tape) I have a protective tube of foam rubber on the top tube (pipe insulator). My friends think I'm being OCD but how many beautiful bikes have use seen with a big chip (or dent) in the TT from the bars swinging around.

[RedRider]

Everything you read on the internet is true.

[cnighbor1]

One the paint companies is advertising a new car paint protection method
something to do with clean the surface than apply a sort of clear coat. that could be all you need
One thing I do is empty the water bottle at the end of day ride over the top tube and down tube than I wipe down to remove sweat on the bottom of the tubes which has salts that attract moisture Over time rust forms

[thwart]

Ah... Um...

Build it, ride it, it can always be repainted and those DeRosa decals sourced from somewhere.

Then again, some helicopter tape on the underside of the downtube and the driveside chainstay may not be such a bad idea.