For your consideration -
Clear finishes break down when they crack. The expansion of the wood along with the elasticity of the finish are key to preventing cracks, along with UV resistance.
Compare Wood This link gives a table of strenght and durability of various woods. IPE is the most durable, readily available and (KEY PT) its stability is ranked third.
US Coating This link is for a new coating from USC that is flexible; cross-linking to the wood.
Anchorseal This link is for USC Anchorseal that is applied to the end cuts as soon as the cut is made. The end cut is the most vulnerable entrance for moisture.
House of Hardwood This mill is located in Los Angeles. I got a $500 quote last year for custom milling 5/4 IPE, grade 1, kiln dried for the widths/lenghts for a 1956 short bed stepside, using the profile found on the MAR-L site with all corners radiused 1/16" (the coating will adhere better to a radius than a sharp edge, reducing cracking).
