Re: [RCSE] Majestic 110 RES from Laser Arts
On Friday 07 January 2005 01.03, Kurt wrote: Dan, Here's a pointer to what I did to my Laser Arts wings for strengthening. http://www.ppssrc.com/carbonwing/carbonwing.html (snip) If I were building a woody that required some additional strength to a wing I would put carbon on the bottoms of both upper and lower spars. The reasons are this, first, carbon fiber is stronger under tension and not compression. Doesn't really help to put it on the bottom of the upper spar, as it will still be in compression - the entire top spar is! Easier to sand the top of the spar smooth, though, if the carbon is on the bottom ... If you add carbon it should be twice as thick on top spar than on the bottom, due to its lower compression strength. That's how Lancair does it, too! A thin aluminium rectangular spar, of soft aluminium, is, on the other hand, very strong in compression and could well be -after it surface has been roughened with a heavy file, or similar, be glued to a wooden spar with epoxy, and held in place with kevlar thread. Soft aluminium have good ageing characteristics, both in tension and compression, while harder qualities have less good in compression, and are harder to roughen as well. Second I would be concerned of the carbon delaminating if it was on the upper surface of a spar. The other thing that I'd consider doing is adding the carbon to the spars prior to assembly. I'd even go as far as using a vacuum bag to apply enough consistent pressure along the entire surface of the spar carbon. I have no arguments against this - sound advice as usual! Yours, Tord PS Glad to be back after a while doing other things :-)! RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
Re: [RCSE] Majestic 110 RES from Laser Arts
Dan, Here's a pointer to what I did to my Laser Arts wings for strengthening. http://www.ppssrc.com/carbonwing/carbonwing.html Bob - Original Message - From: Dan To: soaring@airage.com Sent: Wednesday, January 05, 2005 6:21 PM Subject: [RCSE] Majestic 110" RES from Laser Arts Fellow fliers, I'm looking to build a RES ship to fly in our local club contests. While doing a Google search, I ran across the Majestic 110" RES from Laser Arts. Question: has anyone had any experience with this kit - pros or cons? Flying characteristics? ThanksDan Do you Yahoo!?The all-new My Yahoo! What will yours do?
Re: [RCSE] Majestic 110 RES from Laser Arts
Dan, Here's a pointer to what I did to my Laser Arts wings for strengthening. http://www.ppssrc.com/carbonwing/carbonwing.html Bob Greetings guys There has been a lot of discussion on this reflector about how and where one should attach carbon onto spars to make them effective. If I were building a woody that required some additional strength to a wing I would put carbon on the bottoms of both upper and lower spars. The reasons are this, first, carbon fiber is stronger under tension and not compression. Second I would be concerned of the carbon delaminating if it was on the upper surface of a spar. The other thing that I'd consider doing is adding the carbon to the spars prior to assembly. I'd even go as far as using a vacuum bag to apply enough consistent pressure along the entire surface of the spar carbon. Just throwing my 2 cents in Kurt RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
Re: [RCSE] Majestic 110 RES from Laser Arts
Let's assume that we are talking about spar systems where there are shear webs involved. What we have is a beam in this case. If this beam is rectangular in shape or symmetrical about it's longitudinal centerline, then the top half of the spar assembly is basically in compression and the bottom half is basically in tension. The highest levels of stress occur at the outer surfaces of the spar (i.e., the top and bottom surfaces). It is a fact that CF (spruce, balsa, basswood, for that matter) is roughly twice as strong in tension than it is in compression. It is also a fact that CF is by far stronger in tension AND compression than any of the other materials mentioned here. Thus the reason for putting the CF on the top of the top spar is that this is where the best use of its superior compressive strength can be utilized. If the CF is put on the bottom of the top spruce (or balsa or basswood) spar stock, the spruce just adds weight without adding any significant strength; it might as well then be balsa, foam or lightweight spackle for that matter. You should put the material with the highest compressive strength at the spot where the highest compressive stress will occur and the material with the highest tensile strength at the point where the highest tensile stress occurs. For wing spars or other beams, this is the top and the bottom of the fabrication and the material that has the highest compressive strength and tensile strength (currently available to modelers) is CF. The shear webbing in the spar system prevents inward buckling of the spar caps and the wrapping of the spar with glass cloth, or CF tow, or Kevlar tow CF braid prevents the sparcaps from delaminating or buckling outward. Using a FG or kevlar or CF braided tube over the spar and vacuum bagged is a very good way of constructing a spar system. Since, I don't have a Vacbagging system, I have to wrap my spars by hand. Your comments about - Original Message - From: Kurt W. Zimmerman [EMAIL PROTECTED] To: Soaring@airage.com Sent: Thursday, January 06, 2005 11:02 AM Subject: Re: [RCSE] Majestic 110 RES from Laser Arts Greetings guys There has been a lot of discussion on this reflector about how and where one should attach carbon onto spars to make them effective. If I were building a woody that required some additional strength to a wing I would put carbon on the bottoms of both upper and lower spars. The reasons are this, first, carbon fiber is stronger under tension and not compression. Second I would be concerned of the carbon delaminating if it was on the upper surface of a spar. The other thing that I'd consider doing is adding the carbon to the spars prior to assembly. I'd even go as far as using a vacuum bag to apply enough consistent pressure along the entire surface of the spar carbon. Just throwing my 2 cents in Kurt RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
Re: [RCSE] Majestic 110 RES from Laser Arts
Title: Re: [RCSE] Majestic 110 RES from Laser Arts Dan said: I'm looking to build a RES ship to fly in our local club contests. While doing a Google search, I ran across the Majestic 110 RES from Laser Arts. Question: has anyone had any experience with this kit - pros or cons? Flying characteristics? The Majestic is a popular plane in our club and many have appeared at our RES contests. The laser cut parts fit together nicely. The wing takes a fair amount of work because cap strips are used on the top and bottom of every rib. The plane, built stock, flies quite well. It penetrates better, but doesn't float as well as something like a Paragon. Modifications can help the performance in several ways. Mark Drela's list of suggested modifications is well worth implementing. They are on the Allegro web site and in other places. The supplied fiber glass tail boom has a fair amount of flex. Replacing it with a tapered carbon fiber tail boom will provide more rigidity and also save weight. The stock plane requires a fair amount of lead in the nose ( maybe 8 oz.). The plane can be lightened a lot by using a carbon fiber boom and making an essentially new set of tail feathers out of lighter balsa. Getting rid of the metal tail mounting structures also helps. I have seen two Majestics fold their wings on winch launches. Mark's suggestions for strengthening the spar should make the wing nearly bulletproof. The spoilers are fairly small for a plane this size. The spoilers can easily be made longer spanwise. Yaw stability and rudder authority are improved by using the larger tail feathers suggested. Stability and sink while circling are improved by using the suggested modification of the polyhedral and by adding washout. These modifications take no extra work. Regards, Dick -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Dr. Richard C. Williamson Phone: 781-981-7857 Room C-317 FAX: 781-981-0122 Lincoln Laboratory Email: [EMAIL PROTECTED] Massachusetts Institute of Technology 244 Wood Street Lexington, MA 02420-9108 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
[RCSE] Majestic 110 RES from Laser Arts
Fellow fliers, I'm looking to build a RES ship to fly in our local club contests. While doing a Google search, I ran across the Majestic 110" RES from Laser Arts. Question: has anyone had any experience with this kit - pros or cons? Flying characteristics? ThanksDan Do you Yahoo!? The all-new My Yahoo! What will yours do?
Re: [RCSE] Majestic 110 RES from Laser Arts
Dan wrote: I'm looking to build a RES ship to fly in our local club contests. While doing a Google search, I ran across the Majestic 110 RES from Laser Arts. Question: has anyone had any experience with this kit - pros or cons? Flying characteristics? Some info on improvements: http://isoar.ca/~andrewm/rc/majestic/ Check out the Alegro-Lite archives too for discussion. -- Andrew E. Mileski RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
