chopper gun???

[2.5_stoker]

i have read a couple threads that refer to boats being built/layed up with chopper guns Vs. being hand layed...just curious as to how it works and why it seems to be frowned apon (at least in the threads i read chopper guns were shown in a negative light)

[pyro]

It cuts up and shoots short strands of fiberglass, fed by a spool. The end result is similar to mat. Cheaper, easier, not as strong.

[BUSHWACKER]

www.google.com put in the search bar fiberglass chopper gun there are several good interesting videos

[Forkin' Crazy]

A chopped boat is only good as the gun operator. You get a good experienced operator and he can build a decent part. Light and strong as hand laminated? No, but if you are doing production work they can be a definite asset. I use to run one years ago. They do take extra care to have the right catalyst/resin/glass ratio. You also have to keep them clean and sharp blades in the cutter.

[TooStroked]

Strength in a fiberglass boat comes from the glass fibers and the direction they are oriented in. Long, continuous fibers have the most strength. Weaving and orienting these fibers correctly makes for even more strength. Resin is used to bind the fibers together. Too much resin just adds weight and therefore no additional strength.

A Chopper Gun is basically a resin spray gun with an attachment that chops very short lengths of fiber and mixes them with resin. Building a boat with a chopper gun involves spraying in the gelcoat (just like all construction methods), then spraying in the chopped strand. The problem is that you tend to get a lot of resin (excess weight) and a totally random orientation of very short strands of fiber. In short, it's quick and therefore cheap, but not very strong or light weight.

Boats that are "hand laid" start out the same way with gelcoat, but then specific types of fiberglass mat are laid in in specific orientations and layers to maximize strength. Where does the resin come from? It's sprayed or poured on next, then the matt is completely wetted - trying not to get too much resin in. On more expensive boats, vacuum is used to compress the layers of mat together and remove excess resin. This is called vacuum bagging and generally lightens a given part by 10-30% while actually making it stronger.

Hope that helps.

[FX10 Superboats]

I just repaired a Striper CC that is chopper gunned. Fell off the trailer on the ramp, grindind iver an inch off of glass. Once I started grinding the headaches started. Two inch voids in the glass. The chop was like a sponge. never rolled out. Garbage product in my opinion. From the outside i8t looks like a million dollars. Build wise..... junk. I ground through 1 inch of glass, and didn't come across any roving. Hmmmm Reminds me of the new Whalers. Although. I can't totally slam chopper gun layup. If done properly and in the hands of QUALIFIED guys. It's fine.

[2.5_stoker]

thanks for curing my curiosity guys