TotalBoat ThickSet Cast + Coat versus Fathom

The dividing line is more than depth

ThickSet Cast + Coat and Fathom can both appear in searches for river tables, molds, and resin artwork. Their overlap in project names makes the decision seem simpler than it is. The useful distinction is the combination of depth, amount poured, and how long you can devote to each stage.

The current ThickSet formula is a one-to-one volumetric system suited to thicker coatings and smaller castings. Fathom is a two-to-one volumetric system intended for larger deep pours. Check the full product name and current kit instructions before using an older TotalBoat tutorial; a brand name or abbreviated 'ThickSet' reference is not a sufficient recipe.

A small deep mold and a deep table are different jobs

ThickSet's technical sheet allows a two-inch small casting only within its ten-fluid-ounce quantity limit. Across larger coating or river applications, its stated layer limit is half an inch. Fathom instead permits a two-inch river or slab layer and a deeper smaller-mold casting subject to a mixed-volume ceiling.

Consider what happens when you widen a mold while keeping its depth unchanged. The resin requirement increases even though a quick depth comparison looks identical. That is why neither the word 'deep' nor a single advertised inch figure should decide the purchase.

ThickSet also makes sense to consider when you want to build a thicker finish in manageable layers. Fathom is less attractive for a very thin application: TotalBoat says thin pours extend its cure and recommends another suitable epoxy for sealing porous wood.

Compare a relevant resin kit

TotalBoat ThickSet Cast + Coat: check the selected 1 gallon kit, included components and current offer. Read the formula limits before choosing it for your project.

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Read formula notes and other kit sizes

Match the working session to the layering schedule

ThickSet's documented working period is measured in minutes, whereas Fathom's is measured in hours. The extra time can be useful for organizing a complex casting, but it comes with a different cure and layering schedule. Extra working time should not be confused with an earlier finished piece.

The ThickSet technical sheet gives a minimum four-hour interval between its layers under the stated conditions. Fathom's conservative interval is substantially longer, and its accelerated procedure still requires a minimum wait plus checking that the previous pour has cooled and become firm enough. Merely reaching a number on a timer is not the complete Fathom recoat instruction.

Keep measurement and finishing decisions explicit

Use the ratio corresponding to your measuring method. ThickSet's published weight recipe is 1.11 parts resin to one part hardener; Fathom's is 100:44. A worksheet prepared for one product cannot be reused by changing only the total quantity.

Demolding, light use, and final finishing also need separate entries. ThickSet's instructions distinguish its initial cure from the longer wait before wet sanding or buffing. Fathom warns against removing a casting that remains soft and advises support after demolding.

How to handle the inconsistent published values

TotalBoat's pages contain some mismatches, including a stray larger ThickSet casting quantity in a comparison row and different Fathom full-cure ranges. Use the detailed current instructions to identify the intended limits, and ask TotalBoat to resolve any conflict that changes your project plan.

Choose ThickSet or Fathom because the confirmed casting geometry and workflow fit. This document-based comparison cannot establish that either produces fewer bubbles or better clarity in your particular mold.