What is 2pac? Is it only a spray on?

Printable View

4th October 2008, 12:06 AM
doctorpaul

What is 2pac? Is it only a spray on?

Okay, everybody, before you berate my stupid question, consider me a noob, a very big noob, here to learn

What is this '2pac' stuff that is used for finishing? It is sometimes referred to as a poly, but a poly what?

Is it two pots you mix together, or two coats?

Sorry for the question, but there is no real explanation of what, how and when it is used, and when it is no good!

PS- any chance of having some 'stickies' about the usual questions? Ie how to finish table tops, floors, outdoor furniture, oils, poly, 2pacs, turned stuff, etc?

All help much appreciated!
4th October 2008, 10:55 AM
Master Splinter

2-pac is short for any finish that needs two components mixed together before use; it has a limited life when mixed - typically it is unusable after a few hours as it sets by a catalysed reaction that starts when you mix the two components together.

2-pac can be a clear finish or an opaque paint (most of the commercial paint finishes you'll see on wood - such as those high gloss doors for kitchens - will be 2-pac).

2-pac will generally give you the hardest, glossiest and most resilient finish out of all finishing products.

Products like Wattyl Estapol 7008 are specifically for brush or roller application; the instructions stress that it is not intended for spray application.

While it is possible to spray it on, it is important to use proper safety gear; 2 pac finishes contain isocyanates that can trigger a fatal allergic reaction in some individuals, and they can also cause a sensitivity to isocyanates that results in asthma and other lung problems.

Proper safety gear in this case means a supplied-air respirator and full body protection to stop overspray getting on you (skin contact can also lead to sensitisation).

Normal filter type respirators have the problem that isocyanates can be present in 'adverse health effect quantities' long before you can actually smell them. And if you happen to be an individual with a sensitivity (or have built up a sensitivity over time from working with isocyanates)....

Unlike normal paints - where you know its time to replace the filters as you can smell the paint solvent - by the time you can smell isocyanates, you've already been breathing them in for quite some period of time.

Once the 2-pac has set it presents no health risk.

2-pac is great because it gives a great gloss off the gun, it dries rapidly, and it is a very tough coating. Drawbacks are that while it looks great, its not all that 'field repairable' - when it does get damaged, the only way to make it look better again is to sand and refinish the piece - unlike an oil finish where you just wipe on another coat of oil and add to the patina! I also find that over time, 2-pac tends to delaminate over the really thin sap veins in timber like Jarrah - this can let water through, causing dark spots and timber damage.

My personal preference is for an oil finish - although it requires ongoing maintennance, you effectively get your dining room table 'as new' again for minimal work (less than 15 minutes* twice a year, with something that smells of beeswax, oranges or eucalyptus); 2-pac will look utterly great for a year or two or three but as wear, tear and kids take their toll you'll be looking at something that really needs a sand and refinish at some point (say half a day to sand and respray with the delightful odour of 1-1-1 trichlorosomethingorother etching away at your nose).

*Disclaimer: I probably take longer than this, but thats because I enjoy the smell and the tactile nature of the process, and I like how the finished article looks. If I wanted a maintennance free piano gloss finish, I'd buy a sheet of woodgrain laminex and use that!
4th October 2008, 12:29 PM
Boxmaker

Quote:

Originally Posted by doctorpaul

Okay, everybody, before you berate my stupid question, consider me a noob, a very big noob, here to learn

What is this '2pac' stuff that is used for finishing? It is sometimes referred to as a poly, but a poly what?

Is it two pots you mix together, or two coats?

Sorry for the question, but there is no real explanation of what, how and when it is used, and when it is no good!

PS- any chance of having some 'stickies' about the usual questions? Ie how to finish table tops, floors, outdoor furniture, oils, poly, 2pacs, turned stuff, etc?

All help much appreciated!

Are you having us on Doc? I got up google and typed "2 pac paint" There is more pages than I would bother to count on 2 pac paint
one site is "http://forum.hot4s.com.au/archive/index.php/t-873.html"
Google- as above and you will get upto speed very fast.
13th October 2008, 10:20 PM
Eldanos of KDM

Quote:

Originally Posted by Boxmaker

Are you having us on Doc? I got up google and typed "2 pac paint" There is more pages than I would bother to count on 2 pac paint
one site is "http://forum.hot4s.com.au/archive/index.php/t-873.html"
Google- as above and you will get upto speed very fast.

hehe. Oh well Boxmaker, The Doc may as well come to the experts first :) . Probably just took him a bit longer! Kinda makes you feel special to be able to answer someones question! Especially when it's so easy. (Not to take away from Master Splinters excellent and in-depth answer)