X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from lrcmmta07-srv.windstream.net ([166.102.165.79] verified) by logan.com (CommuniGate Pro SMTP 5.3.2) with ESMTP id 4119282 for flyrotary@lancaironline.net; Wed, 10 Feb 2010 08:29:06 -0500 Received-SPF: pass receiver=logan.com; client-ip=166.102.165.79; envelope-from=montyr2157@windstream.net Return-Path: X-WS-COS: WSOB804 X-Cloudmark-Category: Undefined:Undefined X-Cloudmark-Analysis: v=1.1 cv=3r2JSgKf3DAWF1UyVYlmnXPdxOhsc0knMSxBREytudE= c=1 sm=0 a=oCcaPWc0AAAA:8 a=NMqsQ9wVg9HPSOe-dUQA:9 a=I-4S35niQrhWRQTaCxwA:7 a=AG5UszkV5AnMCrbMj6hIPOMMNVwA:4 a=7nmQfdoUjXMtvErL:21 a=059UoAHuaMiyjOB6:21 a=kviXuzpPAAAA:8 a=Ia-xEzejAAAA:8 a=o2QoyYduAAAA:8 a=5SVOeNthy2uMHzeSwQgA:9 a=rrJaeMsn07f_ZIzd1WoA:7 a=wmNlkdPKQyyIUWEiVM1koQ1Z2v0A:4 a=d-1ze5jHbJEA:10 a=4vB-4DCPJfMA:10 a=EzXvWhQp4_cA:10 a=TlnOPt13aEMA:10 a=/BCh3og2hsim97HtmUyo0A==:117 X-Cloudmark-Score: 0 Authentication-Results: lrcmmta07 smtp.user=montyr2157; auth=pass (LOGIN) Received: from [98.20.208.27] ([98.20.208.27:61095] helo=newbox) by lrcmmta07 (envelope-from ) (ecelerity 2.2.2.45 r()) with ESMTPA id ED/7B-16596-E74B27B4; Wed, 10 Feb 2010 07:28:30 -0600 Message-ID: <599AA160C40845E094A0223506A610AE@newbox> From: "MONTY ROBERTS" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: CAD program Date: Wed, 10 Feb 2010 07:28:20 -0600 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0025_01CAAA22.9F0CB2E0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5843 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 This is a multi-part message in MIME format. ------=_NextPart_000_0025_01CAAA22.9F0CB2E0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Mike, send me a private email and I'll give you my ph#., email bandwidth is = too low.=20 Monty ----- Original Message -----=20 From: Mike Wills=20 To: Rotary motors in aircraft=20 Sent: Tuesday, February 09, 2010 10:38 PM Subject: [FlyRotary] Re: CAD program 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 -------------------------------------------------------------------------= ----- No virus found in this incoming message. Checked by AVG - www.avg.com=20 Version: 8.5.435 / Virus Database: 271.1.1/2678 - Release Date: = 02/09/10 19:35:00 ------=_NextPart_000_0025_01CAAA22.9F0CB2E0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Mike,
 
send me a private email and I'll give = you my ph#.,=20 email bandwidth is too low. 
 
Monty
----- Original Message -----
From:=20 Mike = Wills
Sent: Tuesday, February 09, = 2010 10:38=20 PM
Subject: [FlyRotary] Re: CAD=20 program

Monty,
 
Did a little web surfing today. Lot of = information out=20 there on Alibre, plusses and minuses. Hard to determine whats what = since=20 everything is subject to opinion and prior experience. I've noodled = around a=20 bit with ProE. Designed a few assemblies for UAV related work and did = a one=20 week course on Wildfire about 5 years ago. But havent used it recently = and=20 would probably need to relearn a lot. Considerably less experience = with=20 Solidworks, but what I did find in playing with it is that it is a lot = more=20 user friendly than ProE. I'm more or less used to the sketch concept = so not=20 clear to me what the short coming is with it (never had experience = with=20 anything 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=20 is still a demo available but not clear from the website what you get = to demo,=20 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.=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=20 parametric modeler, and what the negatives are compared to a = parametric. I=20 gather it is really good with surfaces, and good for quickly = developing good=20 conceptual models. Not clear if you can actually get engineering = drawings out=20 of it that you can actually build something with. I'd like to know a = lot more=20 about it.
 
One downside to Rhino compared with getting = into=20 Alibre is initial cost. $1000 unless you can get the student discount = ( I may=20 have to consider going back to school at age 53 just to get the = discount). The=20 demo 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=20 years ago. I think it=92s a great concept. Moderate performance=20 but considerably better than the very compromised Xenos design = from=20 Sonex. The RV-11 became stalled due to his perception that there = was no=20 market. Last update was about a year ago and he said he was working on = it=20 again. But he no longer replies to email questions about it and = has made=20 it clear that he doubts he would ever market a kit.
 
My current glider has the same wings he = planned=20 for the RV-11. I'm pretty sure I can build an RVish sheetmetal = fuselage and=20 tail surfaces similar to what he had in mind. And I assume it can be = done=20 relatively inexpensively. I'm thinking pretty seriously about it. = You've got=20 my attention if Rhino can actually help with all the sheetmetal=20 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=20 conic sections. Conics are THE foundation of all aircraft and = boat=20 lofting. Everything is also sketch based. I don't really like = sketches. I=20 blame Pro E for everybody going to sketches. Even the once great = Unigraphics=20 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=20 that may need changing. It is too limiting for free form parts. I will = at=20 least give Alibre credit for not requiring all sketches to be fully=20 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.=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=20 save you that much in headaches if you are designing an airplane. = Especially=20 if it is sheet metal. You can unwrap all your surfaces and plot out = flat=20 patterns. Or better yet send a .dxf file to the waterjet guy to cut = your skins=20 out with the holes all pre punched just like one of van's airplanes. = You can=20 have somebody 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=20 go together just like a quick build kit. How much is that worth to = you? After=20 that you can make as many as you want, over and over and over. I look = at it=20 and say 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=20 that I can pick up just about any program and be doing work in an = hour. If you=20 don't have the basics a class is a good Idea. You aren't going to get = conic=20 lofting skills from a basic tech school though. You could go to one of = the=20 seminars that Rhino puts on from time to time after you have the = basics=20 down. In the end the only real way to learn is by doing. In = the=20 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=20 the software's fault not yours, you will have arrived. Some folks have = a=20 natural ability for this and others don't. You will know within a = couple weeks=20 which camp you are in, especially if you take a class. You may = hate=20 working in cad, some people do. You may also find it = addictive. Just=20 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=20 off. Google BK flyer. He uses cad to lay out the bulkheads, but = then=20 makes poster board patterns for the skins. You just have to decide = which way=20 you prefer to work.
 
One word of advice in = Rhino.....Planar.=20
 
Monty  
----- Original Message -----
From:=20 Mike = Wills=20
To: Rotary motors in = aircraft=20
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

 


No virus found in this incoming message.
Checked by AVG = -=20 www.avg.com
Version: 8.5.435 / Virus Database: 271.1.1/2678 - = Release=20 Date: 02/09/10 19:35:00
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