Hi Tornado, 

for skimming (also known as faring) a hull, none of these aditives are appropriate.  if you are simply faring and smoothing a hull you would use micro-balloons and make a bondo-like paste.  clc has it at this link:  https://clcboats.com/shop/products/boat-building-supplies-epoxy-fiberglass-plywood/phenolic-micro-balloons.html

woodflour is great for filletting and bonding.  cell-of-fill is mostly for glueing and bonding.  both of them would be extremely tough and difficult to sand.

hope that helps, 

h 

@io games Mixing wood flour and Cell-o-Fill can be a great approach! You could leverage the strength of the wood flour while benefiting from the smoother application of Cell-o-Fill. Just make sure to experiment with the ratios to achieve the consistency that works best for your hull.

For a semi-flat 8'x20' barge hull, you'll likely have a lot of thickened epoxy work ahead.

Hey Jim! Geometry Dash Lite

You're on the right track thinking about mixing wood flour and Cell-O-Fill. Both materials have distinct qualities, so mixing them can give you the best of both worlds.
You’re definitely not overthinking! It’s about getting the right properties for your specific job. A trial mix on a small area of your barge hull can give you a sense of how they behave together before committing to large amounts.

   @escape road 2 Excellent for filling larger gaps and voids due to its fibrous nature.

@block blast It sounds like an interesting project, Jim! From what I’ve seen, wood flour tends to create a stronger and more durable bond due to its fibrous nature, especially for structural applications. 

Hey Jim, wood flour is indeed more fibrous and generally stronger, but its bonding performance can vary. For your large hull project, mixing wood flour with other fillers like cellulosic fibers might enhance both strength and adhesion. This  combination could provide better dispersion and reduce the risk of thickening or poor penetration. It’s worth experimenting with small batches to see how they perform on your specific work surface.

  @crossword When working with epoxy and fillers for boat building, the choice between wood flour and cellulose-based fillers (like Cell-O-Fill) depends on the specific application and desired properties.