chop gun or no chop gun

is a chop gun completely nesessary when building a fiberglass boat? I can seem to find the answers here in the forums. If nesessary, do they all cost so much (5,000 to 7,000) because thats lots of money for a beginner. thanks.

Walli

 

you could hire one. don't ask me where, maybe someone on the this form could tell you.

 

Why use a chop gun

Hand Lay Up laminate, pieces of glass "cloth" "glued" together with resin, is always better than the short fibers from a chop gun. So save on the gun and get better quality.

 

chop guns are for building chinese toilet seats. save your money and build a quality product. HAND LAYUPS ONLY.

 

Quality takes time and practice, jimslade I really like your coment I really agree, Take pride in what you do and a nice hand lay up is the only way!! and if you stay with it youll end up learing a few tricks on fit and finish to make a nice product, Keep your eyes open to what others do and learn from it, good or bad, good luck JC

 

Buy yourself a vacuum pump and infuse it!This is the future,we infuse our 17' RIB it was tested offshore for 2 months with no problems,sometimes in 10' seas in the Gulfstream. This hull and deck only weighs 340#s and is solid as a rock.Infusion is not rocket science you just need to study the process and use quality material,we use Rovicore,Vectorply 3610,and 1708.The next boat we build is the navy seal boat we are going to use the a new material by 3tecs that is supposed a good bit stronger.The best resin we have found is Reichold Hydrex 100 it is a vinyl ester blend and is less than 2 bucks a pound.This boat has a modified cat design we have a 90 hp. e-tec and it runs 52 mph!You can see this boat at www,hydroeye,com
Back to the infusion don't let this process intimidate you we had our problems but you just have to work through them the biggest problem you will have is bridging in the tight corners DON'T use putty 3tecs makes a rope you glue in after your first layer.
Any of your manufacturer reps will help with instructional videos,Comp one has these cd's and will send you one.
Thanks Jeff Therrell

 

Thanks..... Hand Layups only!

 

Do you have any source you might want to share in gettng the insulation and the bleeder cloth? Should there be any specific type of peel ply you would recommend over others? Thanks for any insights.

 

We buy our infusion material at Composites One.We only use peelply to make the breathers and to wrap our colbond feed lines.
You can get a CD from comp one that will give you the basics of the system we use.
Thanks Jeff Therrell

 

If you are building a good amount of parts go with the chopper gun. Remember the chopper gun should be used only as a sandwich bed between your layers of heavy glass i.e. woven roving or knytex. If only doing a few parts hand layup is hard to beat.Chopper guns have a bad reputation because they have been used in the wrong way. Also take into account that gelcoat is sprayed with the same system and technique as chopper guns with different spray tips.

 

Chop gun

In my expereince it takes a long time and a lot of screw ups to lay up with a gun.
The ratio of resin to CSM ,inevitably ends up either to dry or to wet.
But to lay up gel ,they are great.
When I eventualy got my act together,I could lay up a little twelve footer hull and deck in an hour total build time.Im not saying I was knocking them out in my lunch hour, but 10 minutes and one coat was on and two or three of us were rolling out.
To build a couple of boats it seems most appropriate to hand lay up and brush on the gel coat,get a brush that wont lose its hair and load the brush heavy,and brush light.Gel Coat that is.
Cut the mat into handleable sizes,when you start to lay up ,and enjoy the journey.work from the gunwhales to keel as the resin tends to sink with gravity,and dont stop till you finish one lamination in its entirety.dont get to many whiskers,(CSM sticking up out of the layup)

 

With the new FIT tips, and impingement systems out there, and using an inline heater when spraying resin there's no reason to completely rule out chopping. Hand lay ups are very consistant and use less resin in the long run, but at the cost of time. Depending on the parts your trying to build, chopping can be a very feasible solution to your problem, providing you take the time to investigate it, and learn how to use a chop system. Infusion is great and is definately the future of composites, but is expensive in the short term and if you don't do your homework and test on small panels to learn flow rates you can throw alot of parts away and get frustrated.

Hand laying CSM, chopping and infusion all have one thing in common, skilled application and procedures are vital.