X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from fed1rmmtao107.cox.net ([68.230.241.39] verified) by logan.com (CommuniGate Pro SMTP 5.3.2) with ESMTP id 4118826 for flyrotary@lancaironline.net; Tue, 09 Feb 2010 23:38:52 -0500 Received-SPF: none receiver=logan.com; client-ip=68.230.241.39; envelope-from=rv-4mike@cox.net Received: from fed1rmimpo03.cox.net ([70.169.32.75]) by fed1rmmtao107.cox.net (InterMail vM.8.00.01.00 201-2244-105-20090324) with ESMTP id <20100210043816.LEGI20722.fed1rmmtao107.cox.net@fed1rmimpo03.cox.net> for ; Tue, 9 Feb 2010 23:38:16 -0500 Received: from willsPC ([68.105.86.80]) by fed1rmimpo03.cox.net with bizsmtp id g4eE1d00P1k005Q044eF1R; Tue, 09 Feb 2010 23:38:15 -0500 X-VR-Score: -20.00 X-Authority-Analysis: v=1.1 cv=3OYv9oSQMPl2mzQJct9Z0gr0/14v7p3aTRAVsPGESI0= c=1 sm=1 a=XruvlouZCDbGUgEaRUiNZQ==:17 a=krDxLGUekFGO193rxq4A:9 a=uk1j6be_VByx9f7QOZQA:7 a=Onfl9q9qmrVlm_UJmNJjrU8zL_kA:4 a=CE3LSzXg2goIS2ZB:21 a=iY3-3LFIG7Le1Tf8:21 a=o2QoyYduAAAA:8 a=Ia-xEzejAAAA:8 a=kviXuzpPAAAA:8 a=eTYrSi2JclYqu1QChOUA:9 a=pHVbcmGYHGrETTRFNv0A:7 a=X4057Ed2kBcarofuD9k_TycC190A:4 a=TlnOPt13aEMA:10 a=EzXvWhQp4_cA:10 a=4vB-4DCPJfMA:10 a=XruvlouZCDbGUgEaRUiNZQ==:117 X-CM-Score: 0.00 Message-ID: <5330806FDF1047A986BFB371D71EE33D@willsPC> From: "Mike Wills" To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: CAD program Date: Tue, 9 Feb 2010 20:38:14 -0800 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00F3_01CAA9C7.CD9FABE0" X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8089.726 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8089.726 This is a multi-part message in MIME format. ------=_NextPart_000_00F3_01CAA9C7.CD9FABE0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Monty, Did a little web surfing today. Lot of information out there on Alibre, = plusses and minuses. Hard to determine whats what since everything is = subject to opinion and prior experience. I've noodled around a bit with = ProE. Designed a few assemblies for UAV related work and did a one week = course on Wildfire about 5 years ago. But havent used it recently and = would probably need to relearn a lot. Considerably less experience with = Solidworks, but what I did find in playing with it is that it is a lot = more user friendly than ProE. I'm more or less used to the sketch = concept so not clear to me what the short coming is with it (never had = experience with anything else). Can you elaborate a little more on what you mean about Alibre not doing = conic sections? From what I saw today I thought the biggest hang up with = it is that it cant handle surfaces. Seems like pricing has changed numerous times for Alibre. Currently = there are three levels priced at $97, $499, and $999. There is still a = demo available but not clear from the website what you get to demo, how = long the demo period is, or what happens at the end of it. The picture is less clear for Rhino, at least to me. Nothing I find on = the web, either from the Rhino site or others, really helps explain for = the rookie how it works, how it differs from the typical parametric = modeler, and what the negatives are compared to a parametric. I gather = it is really good with surfaces, and good for quickly developing good = conceptual models. Not clear if you can actually get engineering = drawings out of it that you can actually build something with. I'd like = to know a lot more about it. One downside to Rhino compared with getting into Alibre is initial cost. = $1000 unless you can get the student discount ( I may have to consider = going back to school at age 53 just to get the discount). The demo = version of Rhino is presumably full featured (not entirely clear from = the website) but is only good for 25 saves and then it dies. Just to clarify what it is I want to do. I've been wanting a motorglider = for years. Van started on a design for his RV-11 10 years ago. I think = it's a great concept. Moderate performance but considerably better than = the very compromised Xenos design from Sonex. The RV-11 became stalled = due to his perception that there was no market. Last update was about a = year ago and he said he was working on it again. But he no longer = replies to email questions about it and has made it clear that he doubts = he would ever market a kit. My current glider has the same wings he planned for the RV-11. I'm = pretty sure I can build an RVish sheetmetal fuselage and tail surfaces = similar to what he had in mind. And I assume it can be done relatively = inexpensively. I'm thinking pretty seriously about it. You've got my = attention if Rhino can actually help with all the sheetmetal stuff.=20 Mike From: MONTY ROBERTS=20 Sent: Tuesday, February 09, 2010 9:07 AM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: CAD program You can probably get by with the hobby version of Alibre. I think it is = around $250. I can't remember what all the restrictions are. I think you can make Alibre work if all you do is flat wrap developable = surfaces. If you are going to do sheet metal it will probably get you = where you want to go.=20 Alibre's big handicap is that it will not do conic sections. Conics are = THE foundation of all aircraft and boat lofting. Everything is also = sketch based. I don't really like sketches. I blame Pro E for everybody = going to sketches. Even the once great Unigraphics has succumbed to the = dark side. A pox upon the geek who invented sketching! Constraint based = sketching is really good for mechanical parts and mechanisms. Or = something where you have a family of parts that may need changing. It is = too limiting for free form parts. I will at least give Alibre credit for = not requiring all sketches to be fully constrained. That can drive you = crazy. Of course not having them fully constrained means you = occasionally have one blow up. You'll see what I mean.=20 Get the demo version and play around with it. I think you can do the = same with Rhino. Try before you buy. I think you can get the student version of Rhino for $200. That is a = fantastic deal. Even $900 is not bad. Trust me, it will save you that = much in headaches if you are designing an airplane. Especially if it is = sheet metal. You can unwrap all your surfaces and plot out flat = patterns. Or better yet send a .dxf file to the waterjet guy to cut your = skins out with the holes all pre punched just like one of van's = airplanes. You can have somebody with a CNC router make up all your form = blocks for the ribs and bulkheads too. If your cad file is perfect, the = parts will be. They will go together just like a quick build kit. How = much is that worth to you? After that you can make as many as you want, = over and over and over. I look at it and say you can't afford not to = have a cad program.=20 Classroom vs tutorials is a personal thing. I've always been good at the = tutorials. But I've been doing cad for so long that I can pick up just = about any program and be doing work in an hour. If you don't have the = basics a class is a good Idea. You aren't going to get conic lofting = skills from a basic tech school though. You could go to one of the = seminars that Rhino puts on from time to time after you have the basics = down. In the end the only real way to learn is by doing. In the = beginning there is going to be a lot of pounding your head against the = monitor. That's just the way it is. When you get to the point you know = it is the software's fault not yours, you will have arrived. Some folks = have a natural ability for this and others don't. You will know within a = couple weeks which camp you are in, especially if you take a class. You = may hate working in cad, some people do. You may also find it addictive. = Just a warning. I could show you most of what you need to know in an afternoon if you = had the basics down. You could use the Bruce King method for a one off. Google BK flyer. He = uses cad to lay out the bulkheads, but then makes poster board patterns = for the skins. You just have to decide which way you prefer to work. One word of advice in Rhino.....Planar.=20 Monty =20 ----- Original Message -----=20 From: Mike Wills=20 To: Rotary motors in aircraft=20 Sent: Monday, February 08, 2010 9:15 PM Subject: [FlyRotary] Re: CAD program Thanks Monty. Alibre was the tool I was thinking of. Never seen Rhino = but I will take a look. Building an airplane is sort of an excuse to = learn the tool. I suspect that I could design/build what I want without = it. But it might help me visualize the end result before I go to far = down the wrong path. Clearly I'm not going to invest huge $ in a cad = package to build a one off. Mike ------=_NextPart_000_00F3_01CAA9C7.CD9FABE0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Monty,
 
Did a little web surfing today. Lot of = information out=20 there on Alibre, plusses and minuses. Hard to determine whats what since = everything is subject to opinion and prior experience. I've noodled = around a bit=20 with ProE. Designed a few assemblies for UAV related work and did a one = week=20 course on Wildfire about 5 years ago. But havent used it recently and = would=20 probably need to relearn a lot. Considerably less experience with = Solidworks,=20 but what I did find in playing with it is that it is a lot more user = friendly=20 than ProE. I'm more or less used to the sketch concept so not clear to = me what=20 the short coming is with it (never had experience with anything=20 else).
 
Can you elaborate a little more on what you = mean about=20 Alibre not doing conic sections? From what I saw today I thought the = biggest=20 hang up with it is that it cant handle surfaces.
 
Seems like pricing has changed numerous times = for=20 Alibre. Currently there are three levels priced at $97, $499, and $999. = There is=20 still a demo available but not clear from the website what you get to = demo, how=20 long the demo period is, or what happens at the end of it.
 
The picture is less clear for Rhino, at least = to me.=20 Nothing I find on the web, either from the Rhino site or others, really = helps=20 explain for the rookie how it works, how it differs from the typical = parametric=20 modeler, and what the negatives are compared to a parametric. I gather = it is=20 really good with surfaces, and good for quickly developing good = conceptual=20 models. Not clear if you can actually get engineering drawings out of it = that=20 you can actually build something with. I'd like to know a lot more about = it.
 
One downside to Rhino compared with getting = into Alibre=20 is initial cost. $1000 unless you can get the student discount ( I may = have to=20 consider going back to school at age 53 just to get the discount). The = demo=20 version of Rhino is presumably full featured (not entirely clear from = the=20 website) but is only good for 25 saves and then it = dies.
 
Just to clarify what it is I want to do. I've = been=20 wanting a motorglider for years. Van started on a design for his RV-11 = 10 years=20 ago. I think it=92s a great concept. Moderate performance = but considerably=20 better than the very compromised Xenos design from Sonex. The RV-11 = became=20 stalled due to his perception that there was no market. Last update was = about a=20 year ago and he said he was working on it again. But he no longer = replies=20 to email questions about it and has made it clear that he doubts he = would ever=20 market a kit.
 
My current glider has the same wings he = planned for=20 the RV-11. I'm pretty sure I can build an RVish sheetmetal fuselage and = tail=20 surfaces similar to what he had in mind. And I assume it can be done = relatively=20 inexpensively. I'm thinking pretty seriously about it. You've got my = attention=20 if Rhino can actually help with all the sheetmetal = stuff. 
 
Mike

Sent: Tuesday, February 09, 2010 9:07 AM
Subject: [FlyRotary] Re: CAD program

You can probably get by with the hobby = version of=20 Alibre. I think it is around $250. I can't remember what all the = restrictions=20 are.
 
I think you can make Alibre work if all = you do is=20 flat wrap developable surfaces. If you are going to do sheet metal it = will=20 probably get you where you want to go.
 
Alibre's big handicap is that it will = not do conic=20 sections. Conics are THE foundation of all aircraft and boat = lofting.=20 Everything is also sketch based. I don't really like sketches. I blame = Pro E for=20 everybody going to sketches. Even the once great Unigraphics = has succumbed=20 to the dark side. A pox upon the geek who invented=20 sketching! Constraint based sketching is really good for mechanical = parts=20 and mechanisms. Or something where you have a family of parts that may = need=20 changing. It is too limiting for free form parts. I will at least give = Alibre=20 credit for not requiring all sketches to be fully constrained. That can = drive=20 you crazy. Of course not having them fully constrained means you = occasionally=20 have one blow up. You'll see what I mean.
 
Get the demo version and play around = with it.=20 I  think you can do the same with Rhino. Try before you = buy.
 
I think you can get the student version = of Rhino=20 for $200. That is a fantastic deal. Even $900 is not bad. Trust me, it = will save=20 you that much in headaches if you are designing an airplane. Especially = if it is=20 sheet metal. You can unwrap all your surfaces and plot out flat = patterns. Or=20 better yet send a .dxf file to the waterjet guy to cut your skins out = with the=20 holes all pre punched just like one of van's airplanes. You can have = somebody=20 with a CNC router make up all your form blocks for the ribs and=20 bulkheads too. If your cad file is perfect, the parts will be. They = will go=20 together just like a quick build kit. How much is that worth to you? = After that=20 you can make as many as you want, over and over and over. I look at it = and say=20 you can't afford not to have a cad program.
 
Classroom vs tutorials is a personal = thing. I've=20 always been good at the tutorials. But I've been doing cad for so = long that=20 I can pick up just about any program and be doing work in an hour. If = you don't=20 have the basics a class is a good Idea. You aren't going to get conic = lofting=20 skills from a basic tech school though. You could go to one of the = seminars that=20 Rhino puts on from time to time after you have the basics down. In = the=20 end the only real way to learn is by doing. In the beginning there = is going=20 to be a lot of pounding your head against the monitor. That's just the = way it=20 is. When you get to the point you know it is the software's fault not = yours, you=20 will have arrived. Some folks have a natural ability for this and others = don't.=20 You will know within a couple weeks which camp you are in, especially if = you=20 take a class. You may hate working in cad, some = people do. You=20 may also find it addictive. Just a warning.
 
I could show you most of what you need = to know in=20 an afternoon if you had the basics down.
 
You could use the Bruce King method for = a one off.=20 Google BK flyer. He uses cad to lay out the bulkheads, but then = makes=20 poster board patterns for the skins. You just have to decide which way = you=20 prefer to work.
 
One word of advice in Rhino.....Planar. =
 
Monty  
----- Original Message -----
From:=20 Mike = Wills
Sent: Monday, February 08, 2010 = 9:15=20 PM
Subject: [FlyRotary] Re: CAD=20 program

Thanks Monty. Alibre was the tool I was = thinking of.=20 Never seen Rhino but I will take a look. Building an airplane is sort = of an=20 excuse to learn the tool. I suspect that I could design/build what I = want=20 without it. But it might help me visualize the end result before I go = to far=20 down the wrong path. Clearly I'm not going to invest huge $ in a cad = package=20 to build a one off.
 
Mike

 
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