Chopper Gun Chopped Strand Mat, fiberglass boat building / boat restoration

Chopper Gun fiberglass where random short hairs of glass are chopped from a string in a gun that looks like a paint gun and then forced into the air towards a boat mold and then are mixed while still in the air with resin that looks like honey adds bulk to boat construction but is not as strong as other types of fiberglass construction lay ups.

Chopped strand mat fiberglass is a glass mat made up of similar length hairs loosely bound into a mat that is hand laid into a boat mold and then resin that looks like honey is dripped and brushed onto it. As pictured above.

In either boat construction the mix of glass and resin are hand laid / rolled into each other to make a single layer of fiberglass.

As a side note, “hand laid” is an expression used at boat shows. Know which kind the salesman is saying is in his boat; hand laid / rolled out chopper gun or hand laid fiberglass cloth.

These two techniques are not the same.

A Chopper Gun mix has to be adjusted each time it is used and supplies are changed. That mix is can be rich or starved for resin, with each style introducing its own problems to the boat construction. That takes some skill and experience to achieve the right balance of glass and resin.

A mat of chopped glass needs its resin rolled into it, but the rich and starved  aspect is not as dependent on operator skill. Almost anyone walking beside and boat under construction can spot either a starved of rich area and flag it for correction.

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