Bolger Bobcat Build Question

[ken_J_@hotmail.com]

I'm about to order some wood for my Bobcat project. I've located some beautiful Aracca 1/4" plywood with no voids and beautiful faces. My question is; the plans call for 1/4" but this wood is about a 16th under 1/4" even though it says 1/4" on it. Is is normal for plywood to be a little undersized? Could I safely build with this? It will be sheathed with 6oz cloth on one side and epoxied on the other. What do you think?

[JimD]

The wood could be manufactured to metric measurements or possibly it is just 'scant' 1/4", meaning the manufacturer has skimped on the scantling, as it were, to save costs. Either way you'll probably be ok as long as the wood is quite strong and has at least a little rot resistance and you do a good job filleting and taping the joints. This would be a good time for someone who knows what aracca is to chime in. Have you thought about glassing both sides?

[BrianY]

Do you mean "arauco" plywood?

According to the Arauco company website, these panels are made up of 100% Radiata (a.k.a. Monterey) Pine with "composed cores with minimal internal voids" using "exterior phenolic glue" (see http://www.araucoply.com/usa/index.html )

Radiata Pine lumber has a low durability rating. It is porus and readily accepts preservative treatments. According to some who have used it for boat building it also soaks up epoxy very easily (see the discussion here: http://forums.bateau2.com/viewtopic.php?t=4236&sid=86d292813dc1766b1f24430f8579a128).

The plywood is made to metric measurements, thus accounting for the "scant" 1/4" thickness.

I have found no info on the strength rating of the plywood (i.e. how it complares to doug fir ply).

[ken_J_@hotmail.com]

I couldn't really remember how it's spelled but that is correct "Arauco". Thanks for the help. If I end up using it, i'll let you know how it works.

[ken_J_@hotmail.com]

I'm kind of scared now after reading that the wood is very porous. I don't want it to drink up all my epoxy. That stuff isn't cheap! I'll have to reconsider. I'm just having a terrible time finding a source of good wood here in Arkansas.

[P.L.Lenihan]

Before you chicken out on your choice of wood just because it may soak up some nice epoxy,consider a paraphrase from Bolger himself:"the hull is the last place to cut corners....." He was refering to sharpies,if I remember correctly, and big ones to boot, but I would suggest it applies to smaller boats to. What you may end up spending on epoxy could be re-couped from making your own sails from cheap poly tarps or Tyvec.Later,when the budget allows,get yourself a real well cut sail and enjoy some fine sailing is a sweet little charmer.

Peter

[ken_J_@hotmail.com]

It will be a fresh water boat. I'm going to go with the Arauco and glass the boat inside and out. The boat will only be sailed 6 or 7 times a year so it will be pulling pretty light duty. I believe the wood will hold up very well. I'll let you know my impressions of working with this particular wood.