10/23 Raptor Video

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Jay Kempf

Curmudgeon in Training (CIT)
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Tall order to live up to. I can just imagine a BBC1 interviewer bring up this video and questioning the current project lead...
 

flywheel1935

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Downham Market, Norfolk, Great Britain.
So we all wasted 8 minutes of our lives watching PM explain why something he was told would not work, did not work. As much as I try not to watch his YT Channel, I get attracted, like a moth to a flame, then despair at the lame comments from some people who obviously know bugger all about aircraft and engines. Oh well lockdown over soon, back to the 'real' world for most of us !!!!
 

Rataplan

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When you have no materials knowledge/ experience and are too lazy to even look up physical properties of a material you plan to use online- failure is often the result. Could have saved himself 2-4 weeks delay with 5 minutes of research. There are really good reasons why you don't see Delrin used in gearboxes...

The title in the video also applies to the cabin which is another big issue to solve.
I never had heard of Delrin , it just looked like a kind of Nylon so wondering what it is, I Googled "specifications Delrin", took less than 5 minutes.

The question why PM and or how PM came up with Delrin and other questions become more and more a question for psychologist than for technicians LOL
 

rv6ejguy

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I never had heard of Delrin , it just looked like a kind of Nylon so wondering what it is, I Googled "specifications Delrin", took less than 5 minutes.

The question why PM and or how PM came up with Delrin and other questions become more and more a question for psychologist than for technicians LOL
Peter isn't one to tap into the existing knowledge base on any subject which is why he's wasted so much time on fixes and designs which most folks knew could never work. This approach massively slows progress as we've seen.
 

BBerson

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I never had heard of Delrin , it just looked like a kind of Nylon so wondering what it is, I Googled "specifications Delrin", took less than 5 minutes.
You never heard of Delrin but expect he should have?
Maybe his machinist had some laying around. The machinist should know.
 

ImperfectSense

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You never heard of Delrin but expect he should have?
Maybe his machinist had some laying around. The machinist should know.
He is the designer of the aircraft and powertrain, it's his responsibility to understand the design requirements of a part, and to ensure the finished part meets those design requirements. Nobody "expects" him to have heard of Delrin, but REGARDLESS of whether he'd "heard" of it or not, his minimum due diligence would have been to look up the spec sheet and make sure it can withstand the conditions in which it will be operating.

The machinist only knows as much about the final application of the part as PM tells them, and it is not their job to question the designer if there's something they haven't been told. When you hire a machinist, you provide the specifications for a part, and they make the part to your specifications. They are not engineers or designers, and on a project where a man's life hangs in the balance they would not want to (nor should they have to) risk the potential liability if they DID "volunteer" a "part design."
 

TFF

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Delrin is a pretty common material and it was probably picked for price. It was probably always expected to fail, it just wasn’t expected to fail so fast. All he wants is to get past his goal to start a new chapter. Physics keeps getting in the way.
 

TFF

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If it wasn’t so big, every Bennigans and Shakeys pizza would have them hanging from the ceiling.
 

Rataplan

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Feb 14, 2021
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People may find this interesting, I haven't watched it for a couple years:
Quite the set of predictions, lack of knowledge and misinformation...

An excellent example of why you should be quiet until you get your new design flying and proven before you post stuff like this...
In Dutch we say "Don't sell the bear's skin before you have shot him"

All marketing bla bla. Compares it with an existing plane as if his plane already existed... And why not compare it with for example the Velocity? Just to create the impression it is all " New !!! " Like the washing powder advertisements.

PM is an excellent Marketeer .
You never heard of Delrin but expect he should have?
Maybe his machinist had some laying around. The machinist should know.
b
You never heard of Delrin but expect he should have?
Maybe his machinist had some laying around. The machinist should know.
I don't expect anything from PM , and you miss the point , even if you have never heard from Delrin, within 5 minutes you can know averything about it. What has the machinist to do with it? PM is the designer
 

Kiwi303

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Jul 22, 2015
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En Zed. Aka The Shire.
Will the Raptor reach these speeds ?

170 kn top speed ?



View attachment 106209

I've never seen that plane, I looked at the LongEZ and VariEZ but with quoted 58kn stall speed they wouldn't pass NZ microlight rules of 45kn stall. I ended up getting plans for the Jodel D.11 with the Aussie wing tank mod.

The Bateleur at 35kn stall looks like something that Does fit the microlight regs.

As far as the thread goes, i'm only halfway through after ignoring it before, and reserving judgement until the end...
 

Kiwi303

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Jul 22, 2015
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En Zed. Aka The Shire.
I was wondering about the Jet-A vs. diesel so I posted a question. IIRC, the consensus was that while a street diesel would run on Jet-A, it wouldn't be good long term. Diesel has lubricants in it that Jet-A doesn't. So if you want to run Jet-A in an engine that wasn't built for it, you would want to add something whenever you fueled.

At least that's how I remember the thread.
I don't see why ordinary 2 stroke oil won't work in Jet A, if it will lube the insides of a 2 stroke motor, it should be able to lube the insides of a diesel pump and injector unit.
 
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