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View Full Version : Fiberglass or metal nose bowl



Bill Rusk
02-20-2005, 02:23 PM
To all

The Smith Cub comes with a fiberglass nose bowl. I am wondering if I should pony up the 800 bucks for the Univair metal one. Is it worth it? What are the pros and cons of each? The fiberglass feels wavy to the hand and I'm not sure I want to get into the "fill and sand" mode like the guys that build the compost airplanes (AKA Lancair, Glassair,etc.). But at the same time I don't want it to look like poopoo either. Others that have used the fiberglass bowls, did you fill and sand?

Thanks

Bill

Tom Jones
02-20-2005, 02:33 PM
I just reshaped and repaired a fiberclass nosebowl on my L21A. It took hours and hours of filling, grinding and sanding. One of the harder parts is eliminating all of the pin holes that show up and can be very hard to find. The good part is I now have a very nice looking nose bowl. At least I will after the rain stops long enough to shoot color.

Dano Bardwell
02-20-2005, 09:37 PM
hands down pony up for a metal one. I have done a lot of fixes on fiberglass bowls, metal ones seem to be lower maintenance

Steve Pierce
02-20-2005, 10:19 PM
The nose bowls Stoddards sells are reinforced with Kevlar and are very smooth. I simply shot primer and paint. Those soft aluminum nose bowls dent and crack easily and I have spent countless hours repairing them. The split nose bowl Stoddards sells is also very convenient.

labdad32
02-22-2005, 04:12 PM
I just gave Bill $495. for a new split bowl (Plaschem) yesterday. It looks very nice and has all but the lower two fasteners attached. I have to fill the starter hole but I like the idea of not having to remove the blade to gett all the cowl off.

Jon B.
02-23-2005, 09:14 AM
Tom Jones said: "One of the harder parts is eliminating all of the pin holes that show up and can be very hard to find. "

I learned a pretty good technique for this a while ago. The local EAA technical counselor has a well-equipped hangar, so I was repairing my fiberglass nose there. We did a couple of glass layups, filled with the micro-balloons and filed/sanded it smooth. An air hose helps get rid of all the dust, opening any pin-holes.

The first primer coat was barely thinned at all. We shot it on, then used a squeegee to "trowell" it. This filled the pin-holes very nicely. After it dried, we block-sanded with 320, thinned the second coat and it looks really nice.

Jon B.

cubscout
02-23-2005, 12:05 PM
Regarding pinholes and irregularities on fibreglass components, I've had good luck with microballoons in epoxy mixed to "creamy peanut butter" consistency for the larger irregularities, and applied with a bondo spatula, or plastic putty knife. The Superfil by Poly-Fiber works well, too.

I'd avoid the automotive "Bondo" type fillers, intended for use on metal, as they tend to crack out on composite components.

For pinholes, Feather Fill is a very nice spayable/sandable filler that can provide a REALLY smooth surface if you use successively finer sandpaper on each coat; 400 or 600 grit can provide a beautiful base for a really glossy colour coat.

Check out these and similar materials in Aircraft Spruce "Composite Materials" section, or try your local boat materials shop.

Hope this is helpful. Cubscout