Rocker Switch Cover Replacements - 3D Print your own

[Pinecone]

A friend did a 3D modeling of the ETA switch cover.  He sent me a couple of samples to try.  Need to get over to the plane and try them.

Once the file is finalized, I have been talking to AH1 pilot to turn it over to him to make and sell them.

[Phil K]

On 10/27/2022 at 8:03 PM, Alexdangelo said:

Hi All

Purchasing a 80' M20J. Fresh private pilot and in need of a CFI familiar with the make and model. Need transition training and would like CFI to fly back with me from Charleston SC in the next few weeks. 

 

Please let me know if you have any good recommendations.. 

 

Thanks 

 

1 hour ago, Pinecone said:

A friend did a 3D modeling of the ETA switch cover.  He sent me a couple of samples to try.  Need to get over to the plane and try them.

Once the file is finalized, I have been talking to AH1 pilot to turn it over to him to make and sell them.

Thanks for the update I would definitely be interested in buying a handful

[0TreeLemur]

On 11/5/2022 at 2:14 AM, carusoam said:

PLA or poly lactic acid…..

Not only melts really easily… it is also biodegradable… as in edible by bugs and amoebas….
and has a funny aroma when working with it… 

PP thoughts only… not a polymer guru.

Fooled me... 

[carusoam]

The challenge with biodegradable polymers…

Their properties, long term… don’t usually last in a cabin environment…

To make it bug edible… the molecular weight has to be limited… shorter chains are easier to eat.

Shorter chains also cause brittleness, and low impact resistance…

I’d hazard a guess… the PLA intended for 3D printing… is probably trying hard to be the least biodegradable as possible, as well as most impact resistant…

As far as UV resistance goes… that is usually a chemical additive blended into the polymer during a compounding step… along with fire resistance and various colors…

Recycling polymers, bio-degrading polymers, proper disposal of polymers, and incineration of polymers (energy use)… are pretty good alternatives to littering…

+1 for having plastic bags return at my grocery store!  I promise to recycle them…

 

Still not a polymer guru….  
 

Go Mooney bits and pieces!

Best regards,

-a-

[jaylw314]

18 hours ago, carusoam said:

As far as UV resistance goes… that is usually a chemical additive blended into the polymer during a compounding step… along with fire resistance and various colors…

I think you're thinking of ABS, the stuff they make car body panels out of (and the Royalite interior panels we use).

PLA has become dominant in the hobby 3D printing arena mainly because it's so dimensionally stable--it doesn't shrink after cooling, so you can print to pretty good tolerances (mechanical toys) and doesn't warp while cooling.

PET (and PETG) are inherently UV resistant.  Great for putting water in, not great for the environment.  Although UV degradation just ends up resulting in microplastic particles, so I suppose PET gets there slower than other plastics...

TL;DR - Reuse, Repurpose, Recycle... and Resist using!

Edited January 14, 2023 by jaylw314

[larryb]

I print in PETG for almost everything. I’ll print in ABS if I really need the higher temperature rating. I did the wingtip light project in ABS because of the heat. ABS requires a heated enclosure to avoid warpage.

[jaylw314]

2 hours ago, larryb said:

I print in PETG for almost everything. I’ll print in ABS if I really need the higher temperature rating. I did the wingtip light project in ABS because of the heat. ABS requires a heated enclosure to avoid warpage.

If you can break prints up into smaller parts, you can get by without an enclosure for ABS  But yes, I prefer PETG for anything functional.  If I just need it to look good, I'll use PLA though

[carusoam]

On 1/13/2023 at 7:38 PM, jaylw314 said:

I think you're thinking of ABS, the stuff they make car body panels out of (and the Royalite interior panels we use).

PLA has become dominant in the hobby 3D printing arena mainly because it's so dimensionally stable--it doesn't shrink after cooling, so you can print to pretty good tolerances (mechanical toys) and doesn't warp while cooling.

PET (and PETG) are inherently UV resistant.  Great for putting water in, not great for the environment.  Although UV degradation just ends up resulting in microplastic particles, so I suppose PET gets there slower than other plastics...

TL;DR - Reuse, Repurpose, Recycle... and Resist using!

I once saw a small extruder back in the 90s comparing various polymers that were close to being biodegradable… PLA, PVOH, EVOH, starch and others…

There are a bazillion different varieties of each chemical… by the time they get compounded for use….

So today’s PLA… probably is very different than the one I was using back in the day… (thankfully)

Things change a bunch just by the machinery that the user intends to employ…

Injection molding polymers are very different than extrusion polymers…

Molders don’t care about web strength…

Extruders don’t care about Melt flow index…

But, both use the same base chemistry…

Each polymer will have these tech details defined by the manufacturer…

I haven’t seen specifications for 3D printing polymers… they must be interesting.

Do they supply you with viscosity and other process info, or expected finished product characteristics?

 

ABS was very popular for airplane and car interiors…

Cars moved to PP because ABS has the usual age oxidation browning issues, resulting in cracking…

They moved to PP because the propylene science evolved enough over time…. And PP economics are really good.  Note where the traditionally smooth finishes became intentionally roughened up a bit…

ABS resists scratching very nicely… other polymers hide the easy scratches with rougher surfaces molded in…

Mooney moved to fiberglass and fabric covering… 

 

PET… is highly recyclable… being clear it makes great products, and is easy to color if wanted…  it is OK for things that aren’t sensitive to O2…

Chemically, it can be unzipped (de-polymerized)… and recycled infinitely, with perfection…

PETG… is even better if you are packaging O2 sensitive products… Soda bottles, technically, have a really short shelf life…  bottling companies have really good control over how long it takes to have the customer get it in their hands…

Lots of big outdoor signs get thermoformed out of PETG… good outdoor properties…

Hmmmmmmm……

PP thoughts only… (Private Pilot) not a polypropylene scientist… 

Best regards,

-a-

[Z W]

PLA prints very easily.  It doesn't "mess up" as often and you don't have to spend a lot of trial-and-error adjusting temperatures and print speeds to avoid stringing, layer separation, and other problems.  So, it's what most people get started with.  The things you make out of it are surprisingly durable, in my experience, but it's not UV-stable.  And supposedly it will melt in temperatures experienced inside a car or airplane on a hot day, though I've not tested that myself.

I've printed some things in PET-G.  Took quite a while to figure out the settings for my printer to put it out reliably, but after that, it worked pretty well.  Supposed to be UV-stable.  I have some things that have been outdoors in the elements for going on two years that are holding up fine.  Much higher melting point, so unwanted melting not an issue.  Not as toxic to print, and doesn't really require a heated enclosure.

I've printed just a couple of things in ABS.  I do have an enclosure.  Even with that, I found it very difficult to print reliably.  Probably user error.

[carusoam]

There was another thing kind of unique about the 90s PLA…

its rate of crystallization was uniquely slow…

After being formed, then cooled… it was still soft and pliable for some time before turning hard as a rock…

Crystallization probably comes with a small amount of shrinkage, specific to the polymer…

The final PLA shrinkage might take 24hrs to be fully cured…

This would only be noticeable for the parts that clip/click in place on another piece… like the switch caps…

 

UV properties are often blended into the polymer during manufacturing…  the compounding step.  A small percentage of additives is all it takes…

Few polymers are very UV resistant on their own… but adding only a few percent of other stuff can affect its final properties… so not all users will want the same thing…

PET-G comes with some magical properties on its own… but, it’s price was 2X of PET… a big problem when you are using truck loads of it, making single use parts…

Soda bottles…   PETG was too expensive.

beer bottles… PETG was acceptable for a while… great for outdoor use, in place of glass…  good for not getting thrown at refs, light when empty… (unfortunately, too heavy when still full…. They got banned after a short success )

We learned that irate fans will throw a $10 bottle of beer… establishments will remove the caps before serving…

small bottles have a higher surface area to volume ratio... So O2 sensitive products like beer get shorter shelf life with the smaller bottles…

For really interesting finished products… co-extrusion gets used to produce layers of different materials… but, machine complexity and costs increase as well…

 

ABS comes with strong aromas… the S (styrene branch) fills the air… styrene isn’t terribly hazardous to breathe… but may take a day to get out of your nose/clothes…

really fuzzy old memories…and PP thoughts only…  

Best regards,

-a-

[Pinecone]

I have a few test rockers from my friend.

Who is interested in getting 1 or 2 to test?

PM me name and address and I will send them out.

[Pinecone]

OK, I sent out switch covers to some people who volunteered to test them.

So, how do you get the existing covers off?????

[louisut]

On 1/26/2023 at 6:45 PM, Pinecone said:

OK, I sent out switch covers to some people who volunteered to test them.

So, how do you get the existing covers off?????

They're friction fit only, so they just snap off. You might be able to get a good grip with both hands if you set the switch halfway. Otherwise, I'd just pry on one side with a thin screwdriver.

If you have any more to test, I'd be happy to do so. The one I need is for a landing light, but a blank cover would be fine too.

[Pinecone]

PM me your address.  If I have any left, I will send you one to test.

[Robert J. Dean]

We just broke a Landing light switch cover.  As you probably all know, the manufacturer of this switch quit making them.  So I came across this discussion about 3D printed switch covers.  But the last conversation was back in January.  Does anyone know if this approach has been successful and how we can contact the person selling the covers?

 

 

Thank you 

 

Bob

 

 

[PT20J]

Do you have Klixon or ETA switches?

[Pinecone]

The same person makes both types.

@AH-1 Cobra Pilot

 

[PT20J]

Yes, but you still need to know which switch you have because the covers are not interchangeable. Someone posted this helpful photo a while back.

[Robert J. Dean]

Good morning.

 

When I was talking to Lucky of Air Salvage of Dallas, I believe he said they were made my Klixon.  He said that Rockwell Commanders used the same switch.  I could probably confirm this by talking to the folks at Dugosh.  The Mooney Service Center in Kerrville.  

Dugosh did give me the Mooney part number.  It is 930023-215.

 

Thank you,

 

Bob

 

 

 

[prestonvanloon]

Does anyone have stl files to share? I ordered the ETA type from shapeways last year, but saw it's no longer an option there. 

[LANCECASPER]

2 hours ago, Robert J. Dean said:

When I was talking to Lucky of Air Salvage of Dallas, I believe he said they were made my Klixon.  He said that Rockwell Commanders used the same switch.  I could probably confirm this by talking to the folks at Dugosh.  The Mooney Service Center in Kerrville.  

Dugosh did give me the Mooney part number.  It is 930023-215.

A quick google search shows that part number as an ETA switch.

[djt]

I generated .stl files, 3D printed and am using Klixon caps.  They could probably stand some further revision.  The real trick, after getting them to "snap" on, is getting the embedded lettering for the switch label (e.g. STROBES, LDG LIGHT, etc.).  I tried both raised and depressed labeling and ultimately went with depressed lettering that I painted.  PM me an email address, I'll send you a zip file of the stl's.

[Fly Boomer]

6 hours ago, Robert J. Dean said:

When I was talking to Lucky of Air Salvage of Dallas, I believe he said they were made my Klixon.  He said that Rockwell Commanders used the same switch.

I think "Klixon" has entered the lexicon as a synonym for "rocker switch" in the same way "Kleenex" entered the lexicon as a synonym for "facial tissues".

[Robert J. Dean]

Thank you.  As soon as I figure out how to send you a private message I will send you my email.

It may be tomorrow. 

I really appreciate your help on this.

 

Bob

 

 

[Pinecone]

As mentioned @AH-1 Cobra Pilot is producing switch caps for both Klixon (he has been doing this for years) and now ETA Switches.

I had a friend do the ETA print file, and AH-1 Cobra Pilot fine tuned it.  He prints them, sands them, painted them white, then laser etches the logo, then clear coats them.