Professional Application Guide - Alexseal

Fairingfor heavy filling or fairing.The substrate must be clean, dry and free from dust, grease, oil and othercontamination. The substrate should be properly prepared as described in “SubstratePreparation & Priming” starting on page 26.Note:To ensure optimum adhesion, the substrate must be properly preparedbefore priming to ensure system adhesion. Full fairing systems require aheavily abraded substrate. Thin fairing systems of less than 3 mm (0.125” - 0.012”)will require a less aggressive profile to anchor the system. Priming is required on mostsubstrates before application of ALEXSEAL ® Spray Fair 328. For metal substrates,optimum mechanical and corrosion resistance values are achieved by proper surfacepreparation and substrate priming with an ALEXSEAL ® Protective Primer. For GRPsubstrate, use ALEXSEAL ® Finish Primer 442 or Super Build 302. The ALEXSEAL ®Protective Primer should be sanded with 60 - 80 grit after drying for over 24 hours, andbefore application of ALEXSEAL ® Spray Fair 328. Follow the recoat times listed in theappropriate “Technical Data Sheets” starting on page 64 for instructions on applyingALEXSEAL ® Spray Fair 328 over another primer without sanding in less than 24 hours.FairingNote:ALEXSEAL® Spray Fair 328 is a solvent-based sprayable fairing compound.Solvent entrapment can be caused by heavy film thickness when over coatingtoo quickly with the same product or other products, and by low temperature or slowdrying time. Mankiewicz Gebr. & Co. will not accept liability for any damages.Tip:Use the “Application Record” starting on page 144 to document yourapplication process, equipment settings and environmental conditions forfuture reference. We’d recommend you make photo copies or print copies from theonline resources available at www.alexseal.com.Additional NotesFor custom applications of Spray Fair 328 over substrates including epoxy resins,please contact your ALEXSEAL ® representative.ALEXSEAL ® Spray Fair 328 is formulated to be applied by spray gun. It is a very thick,yet sprayable material that requires using a large nozzle and a pressure pot or airless/air assist system for proper application. Refer to the appropriate “Technical DataSheets” starting on page 64 for additional application specifications.The components of ALEXSEAL ® Spray Fair 328 have different colors to ensure thoroughmixing. After mixing, the color of the material should be a homogeneous tan color. Ifthey are not mixed thoroughly, it could result in an improperly cured batch. Mixing canbe done mechanically with a slow turning dough mixer or manually. The mixing in of airbubbles should be avoided.Procedure For Application of ALEXSEAL ® Spray Fair 3281. After surface is properly primed or faired as required, apply 3 coats to a wet filmthickness (WFT) of 16 - 20 mils (400 - 500 microns) per coat. Do not apply morethan 3 coats without allowing to cure overnight and sanding the surface.2. Block sand with 80 - 120 grit sandpaper. Block sanding with 120 grit or finer willhelp prevent sand scratch print-through in the finished system.3. Repeat steps 1 & 2 as required.4. After the surface is faired using ALEXSEAL ® Spray Fair 328 to the desired quality,apply Super Build 302 to achieve a surface that can be sealed prior to topcoating.Proceed to “Surfacing” starting on page 36 for instruction on using Super Build302.34ALEXSEAL ® Professional Application Guide version 0.4.3ALEXSEAL.COM > Europe: +49 0 40 75 10 30 > North America: +1 843 654 775535