Mooney wing tip lens

[Hank]

17 minutes ago, tmo said:

Why isn't this a candidate for an OPP?

It is. Study up on home vacuum forming, it only takes time and practice.

[carusoam]

1) Time 

2) practice

3) a good oven like your wife has the keys to.... see if she has a stretching frame to go with it... A convection oven would be super ideal... even heating for even stretching is important...

4) a decent vacuum like the wife has in her closet... With adjustable vac level... not too strong or too weak...

5) a mold you can make yourself with a single existing part... Hmmmm, if I have a good existing part already....?

6) Some vacuum holes in the mold... Dimensions found in the thermoforming for dummies book... Big in the beginning, tiny near the surface...

7) Lastly, and the hard part... getting good plastic distribution so the wall thickness is even all around...

8) no thinning, no lensing, no extra thickness near the edges...

9) Pre-stretching the polymer sheet with a heated plug would be ideal... for good thickness distribution...

10) For that much money...

• Good impact resistance Should be added in... as would good weather resistance...
• there should be a finished part that matches the Mooney dimensions...
• A CNC tabletop router programmed via a good existing finished part... hmmm that same finished part above?

11) Start with a female mold, again for good thickness control...

12) Its not like our wings are haphazardly assembled in the field... They are precision engineered and built in a precision jig...

13) I wish canopy man was still here...  these are just mini-canopies...

14) We could always visit other canopy builders... there is an EAA resource if we needed to go there...

15) On The wicked low cost end... lots of commercial sign builders Form this kind of stuff routinely, on a much larger scale...Imagine 144 formed and cut at the same time... 12 X 12....

16) fortunately the depth of draw isn’t very deep at all... this keeps the thickness variation in pretty good control...

17) PETG May be an exact replica of the original part with enhanced UV and impact qualities... it’s a common but newer material...

18) All this above X2 except in the mirror image... for the other side...

19) It would be helpful to have good instrumentation... IR thermometer, vac gauge, a fire extinguisher, and a canned plan for a few fancy dinners out if you get caught with parts melting in the kitchen... 
 

Now let’s work on that other light support right behind the lens... it is a crappy thermoformed part as well...

Keep the thermoform lose the crappy...

Keep in mind acrylic sheet can be easy to thermoform... cheap, and readily accessible...

getting time in the kitchen alone could be dangerous...

The aroma of acrylic melting on the cal rods in the bottom of the electric oven won’t go away for days...

Plan and execute carefully... 
 

What’s the minimum quantity required for Whelen to build this as a whole unit including the lights? 
 

PP thoughts only, not a molding expert...

Best regards,

-a-

[flyer338]

On 8/14/2020 at 4:50 AM, tmo said:

Why isn't this a candidate for an OPP?

I think it is a candidate for an OPP, but to do so is beyond my current skill level. The infrastructure investment to produce one part seems like it might be more than the market price of the part. I do not expect to need another right wingtip lens in my lifetime.

I would happily purchase the LASAR product, but it was not available in time for a planned trip. Making the trip with a repaired lens does not tempt me.

[Hank]

4 minutes ago, flyer338 said:

I do not expect to need another right wingtip lens in my lifetime.

Yeah, me too,  when I had hangar rash on the left wingtip. Until I made a 10-minute stop on a BFR and came back to a shattered lens. Then less than a year later, hangar roof leaked and a piece of insulation fell onto the left wingtip, breaking that lens . . .

Life happens. It's making me a good LASAR customer, and I'm getting fast at changing these things out!

[N201MKTurbo]

I used to work for a company that made car stereo amplifiers. We made show cars for trade shows and such. We had a vacuformer and used it all the time. It really isn't much more than a piece of peg board with a box under it hooked to a vacuum cleaner. There is a big heater over the top that looks like the broiler from an electric oven. Cover the unused holes with Masonite. Sometimes you put the plastic sheet in a frame that you can pull down to the vacuum table and sometimes you can get away with just draping the plastic over the tool.

Our guys made the tools by gluing pieces of particle board together to make a block big enough for the part they needed and then removing all the excess with a belt sander until it looked like what they wanted. They could make interior parts for cars that looked like they came from the factory. 

BTW, if you sand too much off, fill with Bondo and sand some more.

[flyer338]

1 hour ago, Hank said:

Yeah, me too,  when I had hangar rash on the left wingtip. Until I made a 10-minute stop on a BFR and came back to a shattered lens. Then less than a year later, hangar roof leaked and a piece of insulation fell onto the left wingtip, breaking that lens . . .

Life happens. It's making me a good LASAR customer, and I'm getting fast at changing these things out!

In 25 years of flying, this is the first wingtip damage I have had to repair. I hope it will be another 25 years before it happens again, and by then I suspect flying will be a pleasant memory.

Karma being what it is, I should probably delete his reply.

[jezzie]

On 8/9/2020 at 9:49 PM, carusoam said:

Hey!     A Jezzie sighting!
 

Long time no see...
 

 

I think we met up at KOSH at the MAPA tent with Mitch about 8 or 9 years ago... GJEZ was undergoing a lot of restoration....

If I’m wrong forgive me....

Other possible places to find acrylic lenses... If Dan is unable... GLAP... https://www.glapinc.com

Best regards,

-a-

Hi carosam, yes I remember. i was able to buy one from Dan  135.00

[flyer338]

Wingtip lens installed. I used a bench grinder to shape and fit he lens. The only material removed was from the rear edges. I worked slowly and carefully. It took about three hours. I used the three drill bits sold by Knots2U - after spending $320 for the lens and three hours fitting it, I was not taking any chances when drilling the screw holes. 

[Missile=Awesome]

On 8/16/2020 at 4:21 PM, flyer338 said:

Wingtip lens installed. I used a bench grinder to shape and fit he lens. The only material removed was from the rear edges. I worked slowly and carefully. It took about three hours. I used the three drill bits sold by Knots2U - after spending $320 for the lens and three hours fitting it, I was not taking any chances when drilling the screw holes. 

Looks really nice, but I will just put a coat over ours with a crack when you walk by