Joe...yep, but I'm taking my time for good reason. I tramping around in left field in an unorthodox approach to rtorcraft design. I wrote to a friend in PA about my thought on physics. I see physics in practical application in trials. What we know of physics has been learned from error and success. Most designers stick to a set of rules and boundaries when designing aircraft. Rightly so because it's pragmatic, predictable. But there's a good deal about physics we are unaware of. If we stay in our safe zone, we choose to set aside our sense of discovery. We know that X applied to Y ends in Z. there be, for example, we get hover and translational rotorcraft flight. If we go out of order, the outcome is undesireable. So, we stick to our rules and theorize about the "what ifs" and never put the theories to practical application because of the unkown. What if we applied "W" to our X, Y and Z with control measures? Because of a theory and lessons learned, most do not choose to attempt a different approach, but what if the theories are wrong? What if we just have not found the "right arrangement" to it's implementation? Just food for thought.
Sorry it's been so long. I was in the field for a week and going to the field for 10 days next week. All that I have been able to do lately is gather parts for when I get a free moment to work. I may be changing web site providers so the "envision helicopters" site may be down for a bit until I get re-established with a new provider.
I hope that you are recovering well! Let me quess...it's your feet! Infantry guys are made of iron so you'll be up and around soon,lol.
Got a question for you since you are a trained machinist. What kind of metal should I use for making shafts for my rotors? I need to couple the two rotors using a speedometer cable core. I think that aluminum is too soft to do the job especially when using "E" clips and set screws. The rotor shaft is 1/8" in dia. and flairs to 3/8" to recieve the speedometer cable held in place by a set screw (3/32").
With regard to rotor shafts, I can tell what I've learned and what some other blackhawk pilots told me when they were building their "from scratch" RC helos.
I tried 1/8" stainless and it bent from the torque right where the drive gear was mounted, but your masts are "free wheeling". Titanium is tough, but it has a "spring" whip effect depending on how long the mast is. Titanium is great for drive trains when carrier bearings are used. It may be ok to use titanium in shorter masts, but again I'm not sure how long your tandem airframe gyro masts are. If you want, I can send you some titanium rod that I did not use it's a bit thicker than 1/8" but not much. No charge of course, because I know you would use it for something.
Regarding the speedo cable, I assume you're "synching" your hubs? If so, maybe try the titanium as "synch drive shaft" with light weight bevel gears and 2 or 3 carrier bearings. Some speedo cables have lubrication inside the sheathing, but some torque is lost through the flexing of the cable inside the cable cover.
I also got some extra carbon fiber sheet and I've learned that if you sand it and glue 3 layers it makes good pillow/bearing blocks for small bearings, yet keeping the weight down. Again no charge. I got alot of raw materials floating around. I think my wife is worried that I will bring it home to Illinois and clutter her house. The blackhawk pilots used 4130 chromoly tubing for rotor masts. I've been looking for tubing that small, but I may need to use solid chromoly.
Let me know if you want the titanium and CF sheet pieces.
let me do some digging, there may be an alloy I've overlooked. I'm headed to Illinois tomorrow so if you need the materials, shoot me an email with your address. I'm already sendy a helo poster to Travis, the Stingray Forum originator. I'll check my email tomorrow before I leave.
I'll run up the metal supermarket tomorrow and get some 4130 rod for my shafts. Sorry I didn't reply sooner but I was in Mentone for the convention.
I took a look at your webpage and it was impressive. I saw your tribute to CJ... I can only imagine what his loss was like for you and your wife. God bless all the gold star families! My young warrior is talking about reenlisting since is getting married.
I'm waiting for parts and I can't wait to get started again. After Mentone, things have been so slow and not much is getting done. I did get an opportunity to talk to some R/C guys and they gave me alot of tips to improve my model.
I hope your LPC's (leather personnel carriers) aka feet are getting better. It's tough for an infantry guy to have foot problems.