What is the theory behind the 4 run no phase method? It is not intuitively obvious to draw the second circle centered on the circumference of the first. I've looked and looked and can only find the how to. I've used the method successfully but didn't know the basis for the different steps...
JohnSchwaner: Thank you very much for your informative post. I will certainly look into this and will probably bite the bullet and get the MS bolts just to avoid the nagging feeling in the back of my head when I'm flying over nasty places and the "new vibrations and noises" start.
SomptingGuy: No I started my professional career in 1965 and retired in 1992. Check it out 27 years. Does'nt count my pre-engineering jobs from 1957 to 1965
40818: Thanks for the meaningful response. I did examine the bolted joint with your comments in mind. As it turns out the stiffness of this joint is already determined by a keying action between two of the pieces joined by the bolts. The bolts are primarily in tension only with little chance...
Well I'm 71 and held 4 different jobs in 27 years. However the last one was doing Star Wars work in the Kwajalein Atoll. The scuba diving and sailing were out of sight. Working for the US Army was another story. An MIT engineer that I knew (I think he was a certified genius) said it plainly...
tbuelna: Thanks for the response and the link. A quick look at AN 5-24 bolts shows single item prices at about $0.84. O.K. multipy it by 10 or even 20 and you are still less than the $20. price I got. I don't see the reason for the high prices. I have bought some 3/8 "Supertanium" bolts of...
I need a small quantity of MS20074-05-24 bolts and to date have found only one source and they want $20 each. Is there a source for these bolts at a reasonable price?
Thanks
gmechanics: The Safari Kit Helicopter was initially issued with all aluminum blades. The current version utilizes composite blades weighing about 37# each. I don't remember the weight of the aluminum blades but I'm pretty sure they were lighter. The reason the manufacturer changed was that...
Vertical Aviation, the home of the Hummingbird helicopter and a blade repair facility for the S52 helicopter has a blade twist jig that looked relatively simple. Try www.verticalavition.com
The twist is very beneficial in load lifting. Ray Prouty has told one helicopter manufacturer that an 8...
DimaC1974: This is interesting data. Do you have the source? We publish the Experimental Helo Magazine and would like to list this information and cite the source.
thank you Klyde
btrueblood. Yikes what McMaster catalog are you looking at? and what is the description? My page 3093 has quick release pins.
Also recent quote from another shop was $198 each for 10..
Thanks
Cory: Thanks for the note on McMaster catalog. Their item is exactly what I was looking for except it is 6061-T6 and I forgot to mention that I was needing grade 5 or grade 8 steel. I've e-mailed McMaster for possible source.
I'm trying to determine if there is a standard stocked item that is a two ended stud with Lh and rh opposing rolled threads. preferably with a wrench useable surface in the middle. Set up charges to produce the onezy, twozies that I need are too much.
Jetmaker: Thanks for the response. I found an equation describing the stress increase due to a small crack. It is scary. I'm now afraid to use a metal fork for my salad without xray or dye penetrant for cracks. The stress concentration generated by a small crack that had to be induced after...
Mike: Thanks for the reply. I've not only looked thru a lot of the Google stuff but I bought a textbook on fatigue design. The mechanism by which anodizing creates conditions where lightly loaded aluminum pieces receive stresses that exceed the Endurance Limit has still eluded me. While the...
Recently there was a non-fatal crash involving an amateur built helicopter. The cause of the crash was a fatigue failure in a 0.5ODx 0.325"ID 27.9" long aluminum control tube. The tube was anodized with color to assist in building an award winning ship. It won at Oshkosh. The question is does...
Mark: Like you I'm a EE and own a two bladed helicopter. I have a Pro-Drive and a DSS balancer and could not always get a phase angle measurement that made sense. I made a bench set up with a D.C. motor and a flywheel that I could control the location of the center of mass of the flywheel...
ameolive: Thanks for the response. Listening to someone in the trade, gives me confidence that I'm headed in the right direction. Shortly after I posted the previous, I encountered a CalTech Phd. EE who had been working for Pratt&Whitney and Hamilton std. doing vibration measurments using a...
I now have satisfied myself that all two bladed rotor systems will exhibit both lift and drag forces, that in forward flight will vary at twice the blade rotationg rate. (I've published an article in Experimental Helo magazine delving into the derivation in more detail). But basically,it is the...
