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Grounded by cowl failure!
http://thorp18.com/thorpforum/viewtopic.php?f=5&t=7311
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Author:  SHIPCHIEF [ Tue Jun 18, 2013 9:07 pm ]
Post subject:  Grounded by cowl failure!

After my morning flight in 'Feisty' a quick walk around inspection revealed 2 pulled dzus fasteners on the bottom of the left cowl cheek. They had pulled out of the lower cowl.
The old fiberglass is soft & wiggly. Kind of rubbery. To many years of hot oily engine nearby?
Now for full disclosure: I just finished my RV-8, and received the airworthiness certificate. I have over 5 hours of ground running time on it's turbocharged Mazda rotary engine (I'm on the flyrotary forum too). So I celebrated the certificate with a brief ground run, run-up and a short 2 seconds of take off power on the runway. The engine screamed like a banshee, took off like a scalded cat, and went POP! The died with grey smoke. What a let down!
But I still have my Feisty T-18! Until this cowl deal :P
Obviously Feisty gets fixed first! Smoke Wagon gets to wait his turn.

Author:  Bill Williams [ Wed Jun 19, 2013 5:23 am ]
Post subject:  Re: Grounded by cowl failure!

Scott, plan a trip and come to Florida and you can make a new one using my molds. I live 40 minutes from the mouse. Bill

Author:  SHIPCHIEF [ Sun Jun 23, 2013 1:04 am ]
Post subject:  Re: Grounded by cowl failure!

Today I decided a trip from Washington to Florida was probably beyond my capability, (thanks Bill) so I forged ahead with a repair. I used some .032 7075 aluminum scrap to make a doubler strip along the bottom left cowl cheek. I removed the Dzus fasteners (except the ends) and installed a bunch of plate nuts to the doubler and riveted the assembly to the lower fiberglass cowl. I assembled the cheek to the jowl ;) and drilled + countersunk the new holes for #8 countersink screws. That lower cowl now has no puckers. It flies different too, less wing heavy on the left side. Don't know if it's faster, but it's not slower. Looks a little ruff with the scars from the old fasteners, but Feisty is back in the air!

Author:  fytrplt [ Sun Jun 23, 2013 6:50 am ]
Post subject:  Re: Grounded by cowl failure!

When I ran a fiberglass cowl, I ended up with an aluminum strip all the way around the perimeter of each cowl to fix the very problem discussed here. I finally made an aluminum cowl as, after 20 years or so, the 'glass finally got too rotten to go on.

Author:  Rich Brazell [ Sun Jun 23, 2013 8:46 pm ]
Post subject:  Re: Grounded by cowl failure!

When I installed my MilSpecproducts.com cowl fasteners , I added a doubler that was riveted upon install . I used Cherry Max rivets to complete the installation per the fastener recommendation . ???

RB O0 POW !

Author:  Bill Williams [ Mon Jun 24, 2013 5:35 am ]
Post subject:  Re: Grounded by cowl failure!

I glassed an aluminum strip along the edge of the cowl which worked for 12 years until I made the aluminum cowl. Funny thing about the aluminum cowl is the engine temperatures went down about 30 degrees

Author:  Hagle347 [ Mon Jun 24, 2013 2:51 pm ]
Post subject:  Re: Grounded by cowl failure!

HI Bill, I'm working on a time frame to come down and make a cowl. Any idea how much cloth I'll need to bring?

Terry

Author:  Bill Williams [ Mon Jun 24, 2013 4:56 pm ]
Post subject:  Re: Grounded by cowl failure!

Terry, I'm waiting on Lee to respond as he just did one and probably has the numbers.

Author:  leewwalton [ Wed Jun 26, 2013 9:37 am ]
Post subject:  Re: Grounded by cowl failure!

Hey guys!
Sorry for the delay! I've already talked to both Terry and Bill but wanted to make a posting here to have it public and recorded. When Bill let us use his molds back in April. I went to Fiberglass Coatings in St. Petersburg.

Here's what do remember purchasing ... for one cowl set and wheel pants.

* 20 yards of 60in wide/6oz fiberglass cloth (standard unidirectional) NOTE: I would up this to 25 yards as at least 4 layups is required, we used 3.
* 20 yards of 3inch 6 oz. fiberglass tape (this is used for the edges and on the stiffeners)
* 1 Gallon Standard Laminating Resin (Epoxy)
* 1/2 Gallon "non-corrosive" catalyst (this is available in rations of 1:1 to 5:1) I used 2:1 which yielded about 30 mins. of working time. Note this is not the mixing ratio .. the "ratio" here refers to cure time
* 20 mixing sticks
* 1 box of rubber gloves
* 20 mixing cups
* 2 white suits (paper lab coats)
* 1 gallon "cleanser" (pretty sure this was Lacquer thinner)
* Two 4 ft lengths of triangular foam (cut again lengthwise in half) these were used as stiffeners
* glass rolling tools one small and one medium (these look like mini - paint rollers)
* 6 rolls paper towels (for blotting the resin out)
* 20 cloth pins (for pinching the glass down in stubborn areas)
* Mold Release

Author:  Gary Green [ Sun Apr 05, 2015 11:24 am ]
Post subject:  Re: Grounded by cowl failure!

All this cowl chatter raises my blood pressure a point or two. A few years ago I loaned the cowl molds that Dave Eby entrusted to my care to Don Doubleday with his fervent promise return them in as good condition as he received them. Every time I see him I remind him that I want them back. So far all I get is double talk.

GG

Author:  Bill Williams [ Sun Apr 05, 2015 11:51 am ]
Post subject:  Re: Grounded by cowl failure!

Gary, I know the concept.......I let my molds get away and it was 1 1/2 years before my brother retrieved them in Atlanta after chasing them for several months. A friend here in Lakeland finally brought them home.

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