Surfacing Technology

FAQ About Duratec

What Duratec or Aqua Buff product should I use?
This answer varies based on project & application. Check out our Hawkeye Playbook and then give our tech team a call!

Does Duratec require catalyst?
Yes, all of the Duratec products require catalyst. We recommend 2% MEKP. We’ve had good success with Norox 925.  (Measure 2% by weight.)

Will hot temperature shorten pot life?
Yes! If temperature exceeds 82° F or 28° C then either cool Duratec or make a slight reduction of catalyst to 1.5%

How long will Duratec last on the shelf?
Under standard conditions (25° C or 77° F) Duratec will last six months from manufacture. Lower temperatures extend the shelf life, higher temperatures can dramatically reduce shelf life.

How does film depth affect cure?
The thicker the film the slower the cure. Thinner films cure fastest.

Do all Duratec products need to be sanded and polished?
Sand all Duratec products. Start sanding as soon as the film is hard enough to not plug the paper. If it takes more than eight hours to sand then you may compound and polish immediately. Otherwise, wait overnight after sanding before polishing.

What will stick to Duratec?
Just about any paint or adhesive. We ask that you sand with an 80 grit – 220 grit sandpaper depending on the application. Please refer to the Duratec Application Guides.

Should I thin Duratec? How will I know how much thinner to add? What kind of thinner should I use?
(A) Thinning Duratec depends on the application and the type of gun being used to apply the product.
(B) Use the minimum amount of thinner that will allow the Duratec to spray out of your gun at 38-42 psi air pressure.
(C) Use the Duratec Thinner #39LAC-3 for best results. If none is available Methyl Ethyl Ketone (MEK) is the second choice.

What will Duratec stick to?
Wood, Urethane Foam, Plaster, Fiberglass- Polyester and Vinyl Ester Resins, most Epoxies (we ask that you do a test for your application). If sealing and coating oily or greasy wood apply the Duratec Polyurethane Sealer 5604-002 prior to applying the Duratec Primers or Topcoats.

Will Duratec adhere to epoxy resin laminates?
Duratec Products will adhere to most epoxy resin laminates if the epoxy surface is properly prepared. First, water-wash with a Scotch-Brite or equivalent abrasive pad to remove any amine blush, then sand with 80 grit sandpaper. Wipe down, then apply Duratec. 
Always test the adhesion between systems that use different chemistries, such as epoxy and Duratec.

How much should I put on?
Please refer to the appropriate application guide on this site for recommended thicknesses for specific applications.

What sprayer/tip combinations, what pressure is required?
You can use a Gravity Feed, Siphon, Pressure Pot or Plural Component type equipment. The tip sizes vary depending on application. For Primers, use a .015-.021 with plural component equipment and for Gravity or Siphon use .070-.110 (1.8mm – 2.7mm). For Hi-Gloss, use .015-.018 with plural component equipment and for Gravity or Siphon use .060-.080 (1.5mm – 2.0 mm). Air pressure should be between 38 – 42 PSI but can be 35 – 50 PSI.

For more information about equipment see our Equipment Guide.

My part has orange peel, what should I do?
Orange peel can be caused by to much air pressure, spraying to close to the surface, product not being thinned properly or not enough product being applied per pass. Balancing the pressures, viscosity, tip size and spray technique will solve orange peel.

How long should I wait before sanding? 
There is no specific time that you should wait before sanding. If you can sand and not clog your paper, then you can continue sanding. 
You may topcoat immediately with another Duratec product. If you are going to topcoat with another product other than Duratec, you must wait at least 8 hours. (We know the compatibility between Duratec products allows for immediate recoat)

For Duratec Primer in-mold use, how long should I wait before laminating?
If laminating onto Duratec with a Polyester or Vinyl Ester wait until the primer is tacky before laminating. If laminating with an epoxy, wait at least 4-5 hours for the Duratec Primer to be fully cured.

I need to patch gel-coat, can I use Duratec?
Blend with Duratec Hi-Gloss Additive (904-001) to achieve a glossy smooth off-the-gun finish. Blending instructions are in the Gelcoat Repair application guide.

What are your disposal recommendations?
Disposal will depend on local regulations. Whenever possible, catalyze and use Duratec.

What if the 707-051 or 1799-052 is hard on the top?
This series of products is manufactured with microspheres that float to the top and pack. It is best to use a mechanical mixer to achieve a smooth blend.

Can I strain the lumps out of the primer after they will not blend back in?
No! You should check the shelf life and make sure that it is not out of date.

Can I surface my mahogany handrails and fighting chair with your Duratec Clear?
Yes! You need to follow our Application Guide on surfacing wood, sand and let sit 8 hours before topcoating with a high quality two part urethane.

Can I use your 707-002 Surfacing Primer under the waterline on my boat?
No! We have an excellent Vinyl Ester Blister/Osmosis System that we recommend. You can find the information under “Marine Applications”.

Can I thin your product with acetone?
For nearly all of our products we recommend the use of Duratec Thinner or MEK Solvent. For Duratec Polyester Base Primer (707-051) and Duratec Vinyl Ester Fairing Primer (1799-052), please see the application guides for our recommendations.