From: owner-krnet-l-digest@teleport.com[SMTP:owner-krnet-l-digest@teleport.com] Sent: Tuesday, April 14, 1998 7:36 PM To: krnet-l-digest@teleport.com Subject: krnet-l-digest V2 #70 krnet-l-digest Tuesday, April 14 1998 Volume 02 : Number 070 ---------------------------------------------------------------------- Date: Sun, 12 Apr 1998 09:28:33 -0700 From: wolfpacks@juno.com (Linda & Paul Martin) Subject: KR: engine baffling I can't tell from the baffling pictures in Steve's book so I'll ask, should there be a hole (to let air out) behind my VW top mount oil cooler? It seems logical to have one so the cooler gets good air flow and so heated air doesn't go to the heads & cyls. Logic aside, I'd rather ask than make another part. Paul M. Ashland, OR _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866] ------------------------------ Date: Sun, 12 Apr 1998 18:44:58 EDT From: Kr2dream Subject: KR: venturi data Does anyone know of a reference for design data or performance as a function of air flow for old-fashioned venturi horns? Any direction would be appreciated. Bob Lasecki KR-2S @ 700 hours in Chicago ------------------------------ Date: Sun, 12 Apr 1998 19:06:47 EDT From: MikeT nyc Subject: Re: KR: Why Gussets? >The "dreaded" gussets give overall contact with the joint on all sides. >Yes, a plywood gusset will join the wood together but not where it counts. >(At the joint). > >The plywood gusset over the joint gives contact on only one side of three >(two) joints. > >Hope this helps. I'm not convinced of this. The purpose of gussets is that with a simple joint, you're gluing end-grain, which is not a strong joint. Yet with the classic KR gusset, guess what's being glued? End grain, exclusively, on both ends of the gusset. Tony Bingelis demonstrates on page 67 of "The Sportplane Builder" that plywood gussets (which are used on both sides) give much greater gluing area than corner-block design of the standard KR gussets, and it's either parallel grain or cross grain, but never end grain. A filler block between the plywood gussets gives yet more strength, but Tony calls it "optional," and exact cutting of it probably doesn't matter because its purpose is to fill the space between the plywood gussets. Tony's analysis is probably referring to wood and fabric planes. On a KR, the skin functions as the equivalent of one plywood gusset, and what KR builders call the "gussets" function as filler blocks. You would have to test to see whether a second plywood gusset on the inside would give greater strength than the filler block for the same weight, but it would certainly be worth making such a test, because they would also be a lot easier to make. As I mentioned in my last post, the early Newsletters permit both gusset-methods -- people have become enamored of the corner block method, perhaps because it's better- looking and maybe because it's so damnably more difficult that they assumed it had to be better. Mike Taglieri ------------------------------ Date: Sun, 12 Apr 1998 20:03:40 -0700 From: Shannan Rheude Subject: Re: KR: Newsletter CD-ROM update Oscar Zuniga wrote: > > Video Bob wrote: > > >Which reminds me. Are the old newsletters still going to show up on > CD? = > > I'm sure that it's a big project and I don't remember who was working > = > >on it. I'm still interested and would greatly appreciate an update. > > Yo, Bob- > > I am the guilty party. Right now, Kerry Miller and Curtis Wright (who > has access to a high-speed scanner) are doing the scanning, as work > allows. All of us seem to have gotten real busy shortly after jumping > into the project, but it looks like the scanning will be done in a week > or two. I have been gathering mailing addresses from all who requested > a copy of the CD-ROM, and have gotten the mailing labels all prepared > and the mailing packs set up. I am monkeying around with Adobe Acrobat > to set up the indexing, and it will all come together fairly soon. > Taxes and work are looming, so once that's over with it may go quicker. > BTW- Mark Langford was 'right on' when he guessed at how many hours it > would take to do this. Still consider it a labor of love, though! Tons > of fun, really. I will post when it's about ready, and will privately > e-mail everybody who requested one, as well as one last call for any > others who are interested. Inflation and stock market developments, > plus cost of my BFR, have slightly bloated the price to $198.99 plus > shipping and handling per copy. > > Just kidding! Still hope to do it for $10-$15 each. ;o) > > Regards, > > Oscar Zuniga > Medford, Oregon > > ______________________________________________________ > Get Your Private, Free Email at http://www.hotmail.com Oscar, Hi! I'm new to the KR-Net. I have a KR-2 that's approximately 60% complete (only 50% to go!). I would very much appreciate getting on your distribution list for the CD of Newsletters. Gee the $150 price is attractive, but unfortunately I've sent all of my cash to the IRS. Ron Rheude Centreville, VA ------------------------------ Date: Sun, 12 Apr 1998 20:23:22 -0700 From: Shannan Rheude Subject: Re: KR: Roll Rate / Edges RFreibe131 wrote: > > I remember Ken Rand's airplane having aileron edges about .75 inches thick. > > Some guidelines suggest the control surface ought to be about 15 percent > thicker than the primary surface at the hinge line. > > Maybe a super effort at edge crispness in counterproductive?? Just a thought. I used to build RC pattern model aircraft and the rule of thumb was that an aileron that ended with square edges at the rear as opposed to a gentle rounding would have much quicker control response. So in that case we would taper the top and bottom to complete the airfoil shape and then sand the back edge square to get a crisp roll response. You don't really remove any of the surface, you just don't round the trailing edge. Hopefully, someone can put their finger on the prior article. Ron Rheude Centreville, VA ------------------------------ Date: Sun, 12 Apr 1998 22:15:45 -0500 From: "Smyre, Nathaniel J." Subject: KR: CD-ROM I'm not sure who is getting the CD made up, but I would like one. My mailing address is: R. Smyre RR #1 BOX 417 Milton, PA 17847 Email: Njsmyre@eden.trevecca.edu Thanks Nate Smyre ------------------------------ Date: Mon, 13 Apr 1998 07:19:18 -0400 From: "Griffing, Bruce F (CRD)" Subject: RE: KR: Why Gussets? Mike- As a woodworker, I agree with your analysis. I also think plywood gussets on the inside would be as strong. End grain glue joints are not strong in tension. But end grain glued gussets would add strength in compression. The added face grain gluing surface of an inside plywood gusset would be strong in both tension and compression. So that seems the best to me. But I also agree that it should be tested before use. Not a difficult test to do. Bruce Griffing > ---------- > From: MikeT nyc[SMTP:MikeTnyc@aol.com] > Sent: Sunday, April 12, 1998 7:06 PM > To: krnet-l@teleport.com > Subject: Re: KR: Why Gussets? > > >The "dreaded" gussets give overall contact with the joint on all sides. > >Yes, a plywood gusset will join the wood together but not where it counts. > >(At the joint). > > > >The plywood gusset over the joint gives contact on only one side of three > >(two) joints. > > > >Hope this helps. > > I'm not convinced of this. The purpose of gussets is that with a simple > joint, you're gluing end-grain, which is not a strong joint. Yet with the > classic KR gusset, guess what's being glued? End grain, exclusively, on both > ends of the gusset. Tony Bingelis demonstrates on page 67 of "The Sportplane > Builder" that plywood gussets (which are used on both sides) give much greater > gluing area than corner-block design of the standard KR gussets, and it's > either parallel grain or cross grain, but never end grain. A filler block > between the plywood gussets gives yet more strength, but Tony calls it > "optional," and exact cutting of it probably doesn't matter because its > purpose is to fill the space between the plywood gussets. > > Tony's analysis is probably referring to wood and fabric planes. On a KR, the > skin functions as the equivalent of one plywood gusset, and what KR builders > call the "gussets" function as filler blocks. You would have to test to see > whether a second plywood gusset on the inside would give greater strength than > the filler block for the same weight, but it would certainly be worth making > such a test, because they would also be a lot easier to make. As I mentioned > in my last post, the early Newsletters permit both gusset-methods -- people > have become enamored of the corner block method, perhaps because it's better- > looking and maybe because it's so damnably more difficult that they assumed it > had to be better. > > Mike Taglieri > ------------------------------ Date: Mon, 13 Apr 1998 06:08:05 PDT From: "Oscar Zuniga" Subject: KR: venturi data >Does anyone know of a reference for design data or performance as a function >of air flow for old-fashioned venturi horns? This is a standard study in mechanical engineering/fluid dynamics, and I'm sure I have it in one of my books somewhere. If somebody doesn't find it directly for you, post me privately and I'll dust off the books. Probably Don Reid can quote it from memory, having just taken his Prof. Engr. exam in Mechanical Engr. a couple months ago... Oscar Zuniga Medford, Oregon ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com ------------------------------ Date: Mon, 13 Apr 1998 06:15:26 PDT From: "Oscar Zuniga" Subject: KR: Why Gussets? I'm not sure I understand the discussion on gussets here. The joint as designed for the standard KR detail proves to be stronger than the wood components, and will break the wood -not the joint- if made right. The pain comes from cutting and fitting all the little gussets, right? so the question was whether plywood semicircles or whatever, are as strong as the corner-block gussets. Now the discussion seems to be trending toward doing _both_, which is apparently of no use at all and only adds weight, given the strength of the corner-block gussetted joint to begin with. I would think that the main concern would be if you didn't skin the sides before you bent them, and had used only the plywood semicircles rather than the 'plans' gussets- then you might have problems with joints. If you skinned the sides, _and_ used the plywood gussets on the inside, then bent the sides- shouldn't be any less strong than the 'plans' corner gussets. Just a matter of choice and appearance. Oscar Zuniga Medford, Oregon ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com ------------------------------ Date: Mon, 13 Apr 1998 13:31:58 -0500 From: "Richard J. Goff" Subject: Re: KR: venturi data Oscar Zuniga wrote: > > >Does anyone know of a reference for design data or performance as a > function > >of air flow for old-fashioned venturi horns? > > This is a standard study in mechanical engineering/fluid dynamics, and > I'm sure I have it in one of my books somewhere. If somebody doesn't > find it directly for you, post me privately and I'll dust off the books. > Probably Don Reid can quote it from memory, having just taken his Prof. > Engr. exam in Mechanical Engr. a couple months ago... > > Oscar Zuniga > Medford, Oregon > > ______________________________________________________ > Get Your Private, Free Email at http://www.hotmail.com KRNetters - I found a good example for a Venturi tube in "Physics for Students of Science and Engineering" by Renick & Halliday. Since this is still the most popular text for 1 st. Physics, you shouldn't have any trouble finding a copy. This is just an special application of the Bernoulli equation. They have an equation showing the difference in height of a column of mercury in a manometer as a function of velocity of the fluid (air). You could solve their eauation for Delta h, and then solve for the difference in pressure between the two areas of the tube. If you need help in marrying all the equations together and solving for delta p (pressure), let me know. Dick Goff, P.E. ------------------------------ Date: Mon, 13 Apr 1998 15:11:09 -0500 From: "A.Doherty" Subject: KR: flight testing Hi KR netters I've spent two hours in my Kr-2 (sob ea 81 1.84:1 reduction)and this is what I came up with: weight 858(plane,pilot,5 gal fuel) prop-52 dia 47 pitch static rpm 5000 (engine) max rpm 5300 (engine) climb 500 fpm @78mph level flight @5000 rpm(engine)(2700 prop)105 mph prop stats say I should get 120mph, but that's clean. I figure prop efficency (avg 85%)loss and dirty under carrage) accounts for the 15 mph loss. So all in all at this point I see little room for improvement. Any suggestions ?????? Al ------------------------------ Date: Mon, 13 Apr 1998 22:30:26 +0200 From: dupont Subject: Re: KR: Why Gussets? Michele Bucceri wrote: > > RFreibe131 wrote: > > > > Does anyone know why all those little gussets are used, other than appearance? > > I have an OPINION that once the plywood is installed, the gussets are along > > for the ride. > > > > I've the same opinion. I think that the gussets may be replaced with > plywood triangle covering the joints. Less boring work, less time to > build, less weight, but same glueing area. On the other side, I've took > a look to four aerobatic airplanes (Avions Mudry CAP 10, CAP 20, CAP 21 > and CAP231), the fuselage is entirely wood, and there are gussets + > plywood triangle !! > So really don't know what to do. In doubt, will leave the gussets. > > Ciao, > Michele Michele,i think you are right about replace the gussets with plywood triangle,this is what i plan to do in my fuselage because with the plywood gussets i can obtain a more clean contact surface so more resistance to my jointing. I'ts my second time for to make an airplane ,my first airplane is build with wood too, and the gussets are also plywood triangle ,that's why i was shocked when i saw this kind of design. So for me it's sure i change the normal gussets for a plywood gussets. à bientot. D.Eric FRANCE ------------------------------ Date: Mon, 13 Apr 1998 16:55:01 EDT From: Horn2004 Subject: Re: KR: flight testing In a message dated 4/13/98 2:11:09 PM, you wrote: <> See if you can reduce weight. Seems like a fairly heavy KR. Steve Horn Dallas, TX Horn2004@aol.com ------------------------------ Date: Mon, 13 Apr 1998 17:12:56 -0400 From: Donald Reid Subject: Re: KR: venturi data Oscar Zuniga wrote: > > >Does anyone know of a reference for design data or performance as a > function > >of air flow for old-fashioned venturi horns? > Probably Don Reid can quote it from memory, having just taken his Prof. > Engr. exam in Mechanical Engr. a couple months ago... > > Oscar Zuniga > Medford, Oregon Memory is a funny thing. . . . . Now, what was I going to say? I have the equation around somewhere, just not handy at the moment. I'll have to look. - -- Don Reid Bumpass, Va. mailto:donreid@erols.com KR2XL at http://www.erols.com/donreid/kr_page.htm Ultralights at http://www.erols.com/donreid/usua250.html ------------------------------ Date: Mon, 13 Apr 1998 14:27:25 -0700 From: Micheal Mims Subject: Re: KR: flight testing Horn2004 wrote: > > In a message dated 4/13/98 2:11:09 PM, you wrote: > > < Any suggestions ??????>> > > See if you can reduce weight. Seems like a fairly heavy KR. > > Steve Horn That weight is not too bad considering thats with the pilot and some fuel. Keep in mind a E81 is pretty heavy (250 pounds) so lightning up this unit may be a pretty hard task. Heck If my project weighs 850 pounds with me in it I will be a happy camper! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Micheal Mims SP290 Spreading its Wings Soon! mailto:mikemims@pacbell.net http://www.geocities.com/CapeCanaveral/Hangar/4136/ Irvine Ca Fax 714.856.9417 ------------------------------ Date: Mon, 13 Apr 1998 18:52:14 EDT From: KR2 616TJ Subject: Re: KR: flight testing In a message dated 98-04-13 16:11:09 EDT, you write: << I've spent two hours in my Kr-2 (sob ea 81 1.84:1 reduction)and this is what I came up with: Any suggestions ?????? Al >> Al, my suggestion......Go fly it some more and have a big time. Congrats again. Dana Overall Richmond, KY kr2616tj@aol.com http://www.geocities.com/CapeCanaveral/Hangar/7085/ ------------------------------ Date: Mon, 13 Apr 1998 18:59:07 +0000 From: Great Plains Aircraft Subject: Re: KR: Flight Testing-update no, have truck, trailer and vw parts will travel. We will be doing a daily put together/test run and take apart VW engine in the workshop. Steve ------------------------------ Date: Mon, 13 Apr 1998 19:00:12 +0000 From: Great Plains Aircraft Subject: Re: KR: engine baffling Yes..STeve ------------------------------ Date: Mon, 13 Apr 1998 21:28:06 EDT From: LVav8r Subject: Re: KR: flight testing In a message dated 98-04-13 16:11:09 EDT, Al writes: << level flight @5000 rpm(engine)(2700 prop)105 mph prop stats say I should get 120mph, but that's clean. I figure prop efficency (avg 85%)loss and dirty under carrage) accounts for the 15 mph loss. So all in all at this point I see little room for improvement. Any suggestions ?????? >> Is that 105mph indicated or true airspeed? If it's indicated (IAS) then take out your trusty whiz wheel and you may find that the true airspeed (TAS) is close to your expected 120mph. Also try to verify with a GPS. Your pitot static system could also be slightly off. Tom Kilgore Las Vegas, NV LVav8r@aol.com http://members.aol.com/LVav8r/index.html KR-2S 3% complete __I__ _______( X )_______ o/ \o ------------------------------ Date: Mon, 13 Apr 1998 21:38:11 -0400 From: Tom Andersen Subject: Re: KR: flight testing I don't see why you would not run the 52" x 47" prop at the same rpm that the VW would run it at, which is about 3500 rpm? It seems that the reduction is way too much for that little prop. The KR-2 was designed to have a high-revving prop to get it's speed (not to mention with a turbo @8000' MSL). The engine turns 5000 on the ground. Wouldn't we adjust prop pitch higher or prop length longer, or reduction lower to utilize that extra power somewhere? - -Tom A.Doherty wrote: > Hi KR netters > > I've spent two hours in my Kr-2 (sob ea 81 1.84:1 reduction)and this is > what I came up with: > weight 858(plane,pilot,5 gal fuel) > prop-52 dia 47 pitch > static rpm 5000 (engine) > max rpm 5300 (engine) > climb 500 fpm @78mph > level flight @5000 rpm(engine)(2700 prop)105 mph > prop stats say I should get 120mph, but that's clean. I figure prop > efficency (avg 85%)loss and dirty under carrage) accounts for the 15 > mph loss. > So all in all at this point I see little room for improvement. > Any suggestions ?????? > Al ------------------------------ Date: Mon, 13 Apr 1998 20:31:23 -0600 From: "gary" Subject: Re: KR: flight testing - -----Original Message----- From: Tom Andersen To: krnet-l@teleport.com Date: Monday, April 13, 1998 8:47 PM Subject: Re: KR: flight testing >I don't see why you would not run the 52" x 47" prop at the same rpm that >the VW would run it at, which is about 3500 rpm? It seems that the >reduction is way too much for that little prop. The KR-2 was designed to >have a high-revving prop to get it's speed (not to mention with a turbo >@8000' MSL). The engine turns 5000 on the ground. Wouldn't we adjust prop >pitch higher or prop length longer, or reduction lower to utilize that >extra power somewhere? >-Tom > >A.Doherty wrote: > >> Hi KR netters >> >> I've spent two hours in my Kr-2 (sob ea 81 1.84:1 reduction)and this is >> what I came up with: >> weight 858(plane,pilot,5 gal fuel) >> prop-52 dia 47 pitch >> static rpm 5000 (engine) >> max rpm 5300 (engine) >> climb 500 fpm @78mph >> level flight @5000 rpm(engine)(2700 prop)105 mph >> prop stats say I should get 120mph, but that's clean. I figure prop >> efficency (avg 85%)loss and dirty under carrage) accounts for the 15 >> mph loss. >> So all in all at this point I see little room for improvement. >> Any suggestions ?????? >> Al > > >I think that I tend to agree with tom on my plane n5391m I ran a 52 x 53( PROPS INC.) - be aware just cause the prop says 52x47 doesn't allways mean exactly that! . It took me 5 different props before I got one that actualy would load the engine staticly correctly. -ie abt 2900 -3050 several of the previous props had the same thing stamped on them, but one which was obviously way under pitched gave me a speed of 140, but at 4000 rpm, and it would have been happy to turn higher ,but I throttled it back because I was afraid of over reving engine. It sure climbed good though!!! It really does sound as though you are under prop-ed . Any chance of borrowing a adj. warp drive or Ivo prop from someone? to try to tweek it up a bit . PROPS INC is as good as their ad. I was getting gunshy (after all the previous failures) and they told me they would guarentee the correct one --Allways room for improvement --or they wouldn't call it EXPERIMENTAL!!!! by golly they did it right the first time !!!! GOODLUCK-&-SMOOTHSKIES garyglasgow@gomontana.com ------------------------------ Date: Mon, 13 Apr 1998 22:47:06 -0700 From: "Bruce S. Campbell" Subject: Re: KR: flight testing A.Doherty wrote: > > Hi KR netters > > I've spent two hours in my Kr-2 (sob ea 81 1.84:1 reduction)and this is > what I came up with: > weight 858(plane,pilot,5 gal fuel) > prop-52 dia 47 pitch > static rpm 5000 (engine) > max rpm 5300 (engine) > climb 500 fpm @78mph > level flight @5000 rpm(engine)(2700 prop)105 mph > prop stats say I should get 120mph, but that's clean. I figure prop > efficency (avg 85%)loss and dirty under carrage) accounts for the 15 > mph loss. > So all in all at this point I see little room for improvement. > Any suggestions ?????? > Al That prop needs to turn 3400rpm. Try another prop that is more efficient at the low rpm or throw away that reduction unit...or maybe just change the ratio. :) Bruce S. Campbell Tampa, Florida ------------------------------ Date: Mon, 13 Apr 1998 21:49:50 -0700 From: Robert Maniss Subject: KR: Progress report Turned my fuselage upright yesterday afternoon. Now it looks even more like a boat. Assembled sides with skins on them and on the belly weigh in at 32 lbs. (includes cross members but no "shelves." Probably shouldn't even have reported this - seems when I begin to feel good about progress something slows me down. See you at Perry. Bob Maniss Abilene, TX ------------------------------ Date: Tue, 14 Apr 1998 00:14:35 -0500 From: "Dean R. Collette, MD" Subject: KR: New Wing Mark and Steve; The last reports that I have seen on the new airfoil for the KR2S had some very promising news, but, I haven't seen anything in the last 6 weeks or so. What's the latest word? As my project is nearing the stage where I am getting ready to build the center spars I'm starting to wonder how big to build 'em. Mark, you had said in a previous email that if you had to do it all over again you would recontour the sides of the fuselage to raise the aft spar about 1.5" to compensate for the 1 degree of wing incidence. My (very) rough look at things with the new airfoils shows that this will still hold true - any thoughts? Dean drdean@execpc.com ------------------------------ Date: Tue, 14 Apr 1998 17:02:03 +1200 From: "DAVID STUART" Subject: KR: Prop information Has anyone got a list of names and addresses of propellor manufactures. My friend Wayne is about to mount a Subaru EA81 using direct drive on his KR-2s and he wants as much info as he can get. Any help would be appreciated. Thanks..........Dave David.Stuart@xtra.co.nz ------------------------------ Date: Mon, 13 Apr 1998 23:36:46 -0600 From: "gary" Subject: KR: Re: Prop information - -----Original Message----- From: DAVID STUART To: KR Newsgroup Date: Tuesday, April 14, 1998 12:18 AM Subject: KR: Prop information >Has anyone got a list of names and addresses of propellor manufactures. My >friend Wayne is about to mount a Subaru EA81 using direct drive on his >KR-2s and he wants as much info as he can get. Any help would be >appreciated. Thanks..........Dave > > >David.Stuart@xtra.co.nz >BEST BET === go to the back of SPORT AVIATION in the prop.adv. sect. ------------------------------ Date: Tue, 14 Apr 1998 01:32:53 EDT From: MikeT nyc Subject: Re: KR: Why Gussets? >> I've the same opinion. I think that the gussets may be replaced with >> plywood triangle covering the joints. Less boring work, less time to >> build, less weight, but same glueing area. On the other side, I've took >> a look to four aerobatic airplanes (Avions Mudry CAP 10, CAP 20, CAP 21 >> and CAP231), the fuselage is entirely wood, and there are gussets + >> plywood triangle !! >> So really don't know what to do. In doubt, will leave the gussets. > >Michele,i think you are right about replace the gussets with plywood >triangle,this is what i plan to do in my fuselage because with the >plywood gussets i can obtain a more clean contact surface so more >resistance to my jointing. >I'ts my second time for to make an airplane ,my first airplane is build >with wood too, and the gussets are also plywood triangle ,that's why i >was shocked when i saw this kind of design. >So for me it's sure i change the normal gussets for a plywood gussets. Something occurred to me reading along in this thread: is it possible that the plywood triangles instead of gussets would make the sides SO MUCH more rigid that they couldn't be bent properly? This would be an unpleasant thing to find out after your sides were done, so how would you test for it ahead of time? If the stiffness were too much, maybe some (or all) of the inner triangles could go on AFTER bending? I assume the aerobatic planes would use both plywood and spruce gussets to get the maximum strength possible regardless of weight, which a KR doesn't need. Mike Taglieri ------------------------------ Date: Mon, 13 Apr 1998 22:52:56 -0700 From: Micheal Mims Subject: Re: KR: Why Gussets? At 01:32 AM 4/14/98 EDT, you wrote: I assume the aerobatic planes would use both plywood and spruce gussets to get the maximum strength possible regardless of weight, which a KR doesn't need. > > > Your right, a KR with a VW would hardly need the extra reenforcement because the VWs run so smooth, on the other hand I decided to use both (ply and spruce gussets) on the aft section of the fuselage and I foamed and glassed the inside of the fuselage from the aft spar forward. Hey,..after all one cylinder on my engine is over 1200cc's! It might shake just a little more than a VW! :o) On the other hand the gussets are not that big of a deal, yes they are a pain in the butt. I think the biggest problem is builders are trying to make them 100% perfect, its not gona happen! Just ask Robert Covington! :o) Just glue the darn things in and use enough epoxy to fill any gaps (no gaps over 1/16 of an inch though). If you find yourself concerned about a joint or two either reglue (add epoxy to the joint) or cut a ply gusset to go on the inside after you skin the outside and assemble the boat. Just Glue It!!!!!! zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz Micheal Mims SP290 Spreading its Wings Soon! mailto:mikemims@pacbell.net http://www.geocities.com/CapeCanaveral/Hangar/4136/ Irvine Ca Fax 714.856.9417 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ------------------------------ Date: Mon, 13 Apr 1998 23:27:57 -0700 From: Robert Covington Subject: Re: KR: Why Gussets? >On the other hand the gussets are not that big of a deal, yes they are a >pain in the butt. I think the biggest problem is builders are trying to >make them 100% perfect, its not gona happen! Just ask Robert Covington! >:o) >Micheal Mims Mike, even with smiley , I wish you would stop speaking for me on some things at times. The above makes me look persnickity or something. I don't try to make my gussets perfect, most of them are not. I just don't like making them :). Your statements above would indicate that I am too perfectionist, which I am not. But I take pride in my work, and I like my gussets to be nice fitting, as so ordered by the 90 percent or better contact rule. I just don't get to the shop, and that alone is why I may seem to be going "slow". I would prefer to create my airplane out of sight of a whole EAA chapter,and airport hangar talkers. So when that problem is resolved, I will be making plane again. I also had to make most of side one's gussets a three way fit because of my nifty parallelogram AS&S longerons, so that was a slow down. I don't mind a glue gap, but I do try to get 95 percent or better contact.I have some pics of my nifty gussets that I can post real soon. Love that Hi8 cam. When I come out with the $200 bag of premade gussets for sale, "why gussets" will be no more, because they will be a steal at even that price. ;) Robert Covington ------------------------------ Date: Tue, 14 Apr 1998 05:29:39 -0500 From: "Mark Langford" Subject: KR: RE: New Wing Dean R. Collette wrote: > The last reports that I have seen on the new airfoil for the KR2S had some > very promising news, but, I haven't seen anything in the last 6 > weeks or so. > What's the latest word? Dean, The first airfoil (the 15% version) is finished. Ashok has posted about 20 pages on the properties of this new airfoil as compared to the RAF48, and they are impressive. Something like same stall speed and much less drag on the top end. I'd give you the URL, but it's on my old hard disk which I need to do a little work on later today to fully recover. I'm sure Steve will be happy to provide it. Ashok's now working on a 16 and 18% version, which will allow taller more efficient spars, as well as a shorter chord. Mark Lougheed's doing some detailed analysis work on the new airfoil as it applies to various versions of the KR, and is still tuning, and Ashok will crunch some numbers when the airfoils are done. Don't start building yet, but incidence may be closer to 0 degrees. Tail incidence is more critical than we might think, as some of Mark's calculations have proved. I wouldn't glue the tail down yet. It just so happens that my tail initial tail incidence may be just about perfect, but that was pure luck. My spars are set up for 1 degree, but with some judicious redistribution of spar material, I'll be able to make the airfoil fit my plane at 0 degrees. I'll just add material to the top of the aft spar and size the airfoil to fit. I needed a little more material there anyway with the way I'm doing ailerons and flaps. I'll look at the 18% version as it applies to stock KR spar spacing later today and will try to report back soon. Bottom line is that we're almost there with the airfoil stuff, thanks to Ashok, Steve, Mark Lougheed, and many others who've pitched in. Steve is about to build two more wind tunnel wings for their "time" in May. He's spending lots of bucks so anybody that feels left out can still contribute to the cause. They've decided not to even bother with the NLF(0115) because this new family of airfoils tailored just for the KR2S is so much better. I've been out of the loop lately as my Windows95 spontaneously combusted last Friday, right after I decided to tear my Scirocco's 5 speed out and fix a whine that the mainshaft had developed. Between those two little problems, I've been kinda busy... Mark Langford langford@hiwaay.net http://home.hiwaay.net/~langford ------------------------------ Date: Tue, 14 Apr 1998 06:44:00 EDT From: JEHayward Subject: Re: KR: Why Gussets? In a message dated 4/13/98 11:55:02 PM Mountain Daylight Time, mikemims@pacbell.net writes: << On the other hand the gussets are not that big of a deal, yes they are a pain in the butt. I think the biggest problem is builders are trying to make them 100% perfect, its not gonna happen! Just ask Robert Covington! :o) Just glue the darn things in and use enough epoxy to fill any gaps (no gaps over 1/16 of an inch though). >> When I was ready to skin the sides, I found that a flox mixture worked quite well for any gaps I'd made where I had goofed a bit. I didn't need to worry about more than a 1/16" gap either. Jim Hayward Rapid City, SD ------------------------------ Date: Tue, 14 Apr 1998 05:57:26 PDT From: "Oscar Zuniga" Subject: KR: Al's Soob-powered KR >In a message dated 98-04-13 16:11:09 EDT, you write: > ><< I've spent two hours in my Kr-2 (sob ea 81 1.84:1 reduction)and this is > what I came up with: > > Any suggestions ?????? > Al >> I will forward your post to the AirSoob list to see what ideas they may have. For now, you have made Jeff Scott very happy about his C-85, since your Soob seems not to be transferring all its HP to the airscrew and Jeff thinks there is no way the liquid-cooled jobs can compare to the air-cooled ones ;o) But 105 MPH doesn't seem right. Regards, Oscar Zuniga Medford, Oregon ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com ------------------------------ Date: Tue, 14 Apr 1998 08:23:05 -0800 From: Bruce Toscano Subject: KR: Urethane Foam I've sent this post 4 times and it never appears . . . I wonder where they all go? Dow shows 2 urethane foams available: Trymer 1800 @ 1.8 lbs density and Trymer 2000 @ 2.05 lbs density. Which one is everybody (urethane users please) using? Price really is not a factor . . . there is some difference in strength and weight. Thanks for your input . . . if this evey makes it. Bruce ------------------------------ Date: Tue, 14 Apr 1998 13:44:30 EDT From: Davinick2 Subject: Re: KR: Why Gussets? In a message dated 98-04-14 01:34:47 EDT, you write: << Something occurred to me reading along in this thread: is it possible that the plywood triangles instead of gussets would make the sides SO MUCH more rigid that they couldn't be bent properly? This would be an unpleasant thing to find out after your sides were done, so how would you test for it ahead of time? If the stiffness were too much, maybe some (or all) of the inner triangles could go on AFTER bending? >> This is what I did. I put the Epoxy on my gussets as if it were wood glue veerrry thiiiin. I later found out you should use plenty of epoxy in the joint and wipe the rest away after clamping. To ease my mind I put plywood covers over all the gussets after the boat was built and all external plywood was mounted. Worked very well. Nick ------------------------------ Date: Tue, 14 Apr 1998 15:51:39 -0400 From: "Richard Parker" Subject: Re: KR: Why Gussets? > This is what I did. I put the Epoxy on my gussets as if it were wood glue > veerrry thiiiin. I later found out you should use plenty of epoxy in the > joint and wipe the rest away after clamping. What is that Saying? "If all else fails read the instructions." ------------------------------ Date: Tue, 14 Apr 1998 15:33:18 -0700 From: "Bruce S. Campbell" Subject: Re: KR: Prop information DAVID STUART wrote: > > Has anyone got a list of names and addresses of propellor manufactures. My > friend Wayne is about to mount a Subaru EA81 using direct drive on his > KR-2s and he wants as much info as he can get. Any help would be > appreciated. Thanks..........Dave > > > David.Stuart@xtra.co.nz David, Brian Whatcott has a very complete list. E-mail him and I'm sure he would be happy to e-mail it back to you. Bruce S. Campbell Tampa, Florida ------------------------------ Date: Tue, 14 Apr 1998 21:30:44 -0400 From: Dennis Ambrose Subject: Re: KR: Re: KR Gear (for free) If anyone is still trying to keep their retracts system operational, I have a complete setup to give away. I'll be going to Sun n Fun and am willing to bring all pieces except the springbar. Let me know SOON!! so I can add them to my packing list!! Regards Dennis (in Toronto) At 11:18 AM 4/3/98 -0500, you wrote: >for all you slow pokes I just called him. They should be on the truck to my >house this weekend. > >Richard Parker >Jaffrey, NH > >---------- >From: Mike Filbrandt >To: KR-List >Subject: KR: KR Gear >Date: Friday, April 03, 1998 11:11 AM > >Fellow KR-Netters, > >Got an E- from a gent yesterday who has a new retractable main gear for a >KR that he wants to get out of his hangar. Anyone interested can have them >for the taking. They are located in Paso Robles, Ca. For further info, >contact: > >Bill Cartwright >PRUA241@aol.com >Phone: 707-494-9593 > > > >Blue Skies, > >Mike >Sparta, Wi. >redbaronflyrs@centuryinter.net > > ------------------------------ Date: Tue, 14 Apr 1998 21:30:54 EDT From: DC4FREE Subject: Re: KR: '99 Gathering The Arlington Fly-in is held the 2nd weekend in July and runs from the Wed. before the 2nd Sat. thru Sunday. I've attended the last 5 years and can only recall 1 KR-2 in that time. The Fly-in folks are great to work with and would be happy to setup an area for a KR-2 group. They would love to have a workshop or class on building a KR in one of the event tents. ------------------------------ Date: Tue, 14 Apr 1998 18:23:25 -0700 From: "John Bouyea" Subject: KR: Re: Prop information this info is posted courtesy of Brian Whatcott on: http://kr2s.timberline.com/krnet/digests/propslist.txt John Bouyea johnbouyea@worldnet.att.net kr2s - building the spars Hillsboro, Oregon - ---------- > From: DAVID STUART > To: KR Newsgroup > Subject: KR: Prop information > Date: Monday, April 13, 1998 10:02 PM > > Has anyone got a list of names and addresses of propellor manufactures. My > friend Wayne is about to mount a Subaru EA81 using direct drive on his > KR-2s and he wants as much info as he can get. Any help would be > appreciated. Thanks..........Dave > > > David.Stuart@xtra.co.nz ------------------------------ End of krnet-l-digest V2 #70 ****************************