Acrylic Urethane or Acrylic Lacquer Clear Coat

Back by popular demand, the general all-things Road forum!

Moderator: robbosmans

Post Reply
rgamble
Posts: 73
Joined: Wed Feb 01, 2012 12:34 am

by rgamble

Recently I was fortunate to acquire an unbranded (non Chinese) Toray 700 matte UD frame.

My specific question regards which type clear coat noted above would best interact with the carbon in a nondestructive way?

If any of you can share insight regarding a pigmented base coat (gloss black for example) I'd be really interested in your experience/recommendation in that regard as well.

Thanks in advance -- Rick

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



jano
Posts: 151
Joined: Sun Oct 21, 2012 8:15 pm

by jano

Lacquer contains solvents and will chemically interact with the base layer on your bike.
Urethane is a two part clear coat that cures by hardening and not by evaporation of solvents.
Safest bet would be the urethane clear coat.

fdegrove
Tubbie Guru
Posts: 5894
Joined: Tue May 03, 2005 2:20 am
Location: Belgium

by fdegrove

Hi,

My specific question regards which type clear coat noted above would best interact with the carbon in a nondestructive way?


To the best of my knowledge no type of clearcoat could possibly intrewract with CF in a destructive way. CF composites are pretty inert to chemicals except for toluene.
However, any acrylic based paint/clearcoat can interact badly with un underlying non-acrylic (aka synthetic paint) coating.

Ciao, ;)
Being a snob is an expensive hobby.

rgamble
Posts: 73
Joined: Wed Feb 01, 2012 12:34 am

by rgamble

Thank you for your responses. They're highly valued.

Unless some retired NASA type weighs in I'll go with the following solution:

http://www.repaintsupply.com/pd_2_part_2k_aerosol.cfm

There's an interesting video found there illustrating it's use. A key benefit from my perspective is it's turn key nature. No pots, mixing, clean-up, etc.

DaveS
Posts: 3913
Joined: Fri Mar 24, 2006 1:26 pm
Location: Loveland Colorado

by DaveS

The bigger issue is durability. Lacquer is cheap to buy and dries fast, but it chips very easily. Urethane is far more durable, but it's more expensive and the spray can has a limited time before the paint hardens in the can.

Either product could interact with some other clearcoat on the frame, unless all of it is removed. Urethane is not devoid of solvents. It can be thinned, just like lacquer. One test for compatibility is to put some urethane solvent on the frame to see if it softens the surface or causes wrinkling.

http://www.repaintsupply.com/pd-ru-311- ... educer.cfm

FWIW, even lacquer is now available as a catalyzed product. It's still the preferred clearcoat for interior woodwork in new homes.

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



bicicleta
Posts: 76
Joined: Thu Sep 29, 2011 7:20 am

by bicicleta

It really depends on how much you want to spend and what kind of quality finish you want to get.

If you're in the states check out www.southernpolyurethanes.com, they sell top quality polyurethane clear coats.

I've used them myself for a number of years in the auto refinish industry and have done a couple of bicycles with this
material. My current bike is a Cervelo RS that I sanded down to raw carbon in some places, applied epoxy primer to it, then PPG Global basecoat and SPI production clearcoat, the finish is great and very durable, mind you I must have added 100 grams in the process.

For a raw carbon frame I wouldn't think twice about using straight SPI clear on it, you will need a least a small compressor and a mini gun to spray it, but it might be worth the expense if you do it right, and trust me, chances are that you would do it again on a number of different cycling parts, so it might be worth it down the line.

Check out Bohemian bikes online, he uses SPI exclusively on his bikes as well.

Just my $ .02 from working in the auto body industry and refinishing a couple of bikes and parts.

Post Reply