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Topics - Deerslayer

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1
Here is a simple experiment, which anyone can perform, that demonstrates the difference in drag between a free-wheeling prop and one that is held stationary.

https://www.youtube.com/watch?v=g5eUrI6vxco&feature=youtu.be

There is a useful extension to this which could again be proven with a simple experiment, i.e., mount the prop onto a motor on a similar test rig and see what happens in the case where the prop is held at a slow idle.

Why should we care about this?

Note that in full scale multi-engine aviation, if an engine stops, the pilot immediately commands the prop to feather. that increases its pitch to present the minimum drag and lift. It will stop rotation for the duration, thereby making the best of a non-ideal situation.

In flying electric models, we typically see landings taking place with the motor off, prop most likely stationary - non feathered, just not developing enough blade lift to keep rotating. At the same time, the landing may seem to be longer than perhaps is desired. It would probably be more efficient to keep the prop rotating at a slow idle, with the "prop disc" then creating significant drag and shortening/steepening the approach and landing. Wouldn't it? My own experience is a definate Yes, especially with powered sailplanes, where landing in a confined area can sometimes be a bit dicey. In that case, if you have a folding prop, holding a minor amount of power right up until the flare will prevent the prop from folding and will effectively employ a great spoiler.   

Another observation: Have you ever had a glow or gas engine quit in air and noticed that the plane might just glide better and be going faster during the landing? The prop is not spinning, so you are part way toward a true "feathering" of the prop, with resulting low drag.

Also, say you have trouble getting a short approach and landing, try cutting back to idle and putting the nose down to pick up some speed early on; the prop will be creating very high drag due to the reversed direction of air through the disc and you may be able to achieve a steeper approach without building up excessive airspeed.

Think about it!

2
For those long days of being stuck inside, here is some very worthwhile reading. This is recognized as perhaps the most authoritative book out there on the subject of flying (full scale, that is). Got a question about some aspect of flying? - you should be able to find the answer in here.  Enjoy!

https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/media/pilot_handbook.pdf

3
General Discussion / Hobbyists helping the cause
« on: March 28, 2020, 09:06:41 AM »
There have been a number of media reports and videos regarding a worldwide effort to produce some of the critically needed medical items.

I forwarded one of the articles to several of our Members who I know have 3D printers. This was probably not news to them.

One of our Members (unnamed out of respect for his privacy) responded that he has been printing face shields for use by operating room staff at KGH, where such items are scarce. What a great thing to hear! Your note back turned our day around significantly!

There may be others amongst us who have the hardware capabilities to contribute to such efforts. (I don't, although I wish that I did). They may already be doing such work. It would be great to hear about, and to acknowledge, their efforts.

Around the country, and the world, there are libraries and educational institutions that are making available their 3D printers to contribute. There are some groups in our area doing this work at home or elsewhere.

One thing in common is that these individuals are donating their time and materials to this cause. Is there a way to help them, perhaps with the cost of materials?

To any of you folks who are producing such items, we would certainly like to hear of your efforts and/or whatever we can do to help. If you wish to remain anonymous, consider sending me an email outlining what you are doing. With your permission, I will post it as a quote with your name withheld, if you wish.

It is frustrating for many of us to have to sit back, isolated, and unable to directly contribute to such a cause. Knowing that some of our friends are able to do something makes life seem a lot better. Can we help them?

4
KRCM FIELD STATUS / Introduction
« on: March 10, 2020, 11:15:49 AM »
For 2020, Bruce Pardo is in charge of Field Maintenance, which includes organizing of grass cutting.

He, along with his team of volunteers, will try to keep the Club informed of ... whatever they want to!

Please be aware that mowing sometimes has to be done on short notice and there could be a very brief inconvenience to someone who is out to fly.
No one gets paid to do this, it is not all glamour, they are all our fellow flyers who are trying to keep this as the best flying site anywhere.

There may be requests posted from time to time for help with specific task, such as Spring cleanup, rolling, tree trimming, road maintenance, etc.

5
Plans, Projects, Building and Flying Tips / Servo removal
« on: March 06, 2020, 06:43:32 AM »
There are a lot of ARFs in our collective hands, predominantly constructed of some sort of foam.

Many of these owners will sooner or later need or want to remove a servo or perhaps a receiver or even some weights (I have done all of this). We find that sometimes the things are stuck in place as if someone's life depended upon them staying come hell or high water. Very nasty!

Sometimes  the only way you can get the thing out is to start cutting, gouging and prying, possibly making a major mess of the foam.

If you are lucky, you can use a solvent to break the mechanical bond between the servo and the foam. The Flitetest guys put me on to this a long time ago.
The usual solvent is ordinary isopropol alcohol from the medicine cabinet. It will not damage plastic or foam or paint of any kind that I have encountered.

Soak the joint area, either by dripping the alcohol around it or using a small paint brush, kept soaked. Try to start prying the glue away from either the servo or the foam or perhaps both, at one or more places. An Exacto knife, dental pick (my preferred method) or such may work best. Once you start to lift even the tiniest edge, keep soaking that area. You should find that it gets easier to pry more of the joint apart, especially if you pause frequently.

Be careful. Some plastics, particularly the cases of our beloved HXT and Turnigy type servos, are easily cracked and broken. Not a big concern if you just intend to junk it.

Unfortunately, some factories and even some modellers like to slap their adhesive all around a servo, including underneath it. This makes removal particularly difficult. With some luck, you can break the bond around the visible part of the servo and pour lots of solvent into the gap. You may need to wait a few seconds or a couple of minutes for it to take effect.

The principle involved id that the alcohol is very low viscosity and density, as well as being quite volatile. This means that it will "wick" into microsopic spaces, and vaporize, expanding that space. 

When you have extracted the object, you can use more solvent to clean it up. I have servos that have been removed, the gear train replaced, reassembled and they are indistinguishable from brand new ones.

When the time comes to re-install the servo, push it part way in, apply just a bit of hot glue at a couple of places, preferably at or under the tabs, and then fully seat it. It should be solid as a rock, yet you can extract it easily, if necessary, using this solvent technique.

IMPORTANT NOTE:
I was stumped while trying to remove a defective servo from my (Joysway) Hobby King Skipper. Alcohol did  not work. The crap they cemented this thing in with seems like what is used on high end double-sided tape, i.e., it remains extremely sticky and terrible to get off of anything - including fingers!
In my desperation, I noticed a little bottle of something called Un-Cure I had bought many dog years ago but did not recall ever using. It came from the local hobby shop, sold as a CA debonder.  So, I dribbled some onto a piece of scrap foam to ensure that it didn't just dissolve the object. Then, I used the same technique as described above. Voila! It worked. I will find out for sure, when I find a suitable replacement servo, that there is  no residue which would defeat the new hot glue bond. I have no idea what chemical this stuff is, but at least I have a clean removal and ten whole working fingers.

6
VIDEOS and PICTURES from KRCM Events and Activities / Wing Fling !
« on: February 23, 2020, 04:36:55 PM »
Learn how to launch a flyng wing - from a pro!
It was a howling wind at the KRCM Toyground, but Harold and I felt that we just had to shoot this video. Sorry about the poor sound quality, tje Handycam really picks up the wind noise and Openshot has no way to reduce it. Guess I should have yelled?

https://youtu.be/G8MpXteNexU

7
On a beautiful post-Groundhog Day afternoon, the infamous Tree Cub once again made an impressive appearance. It somehow reminds of the song, The Cat Came Back (the very next day).

There was some nice flying by both Harold and Dwayne, while I struggled to aim my Handycam in the general direction of the action. Most of time I was shooting blind, as the extremely bright day, extremely darkened glasses, and LCD screen on the camera, all conspired against me. Point and shoot was pretty much the skill portion of the effort.  Future work will be done via the new helmet cam arrangement that I just set up, it works for the Handycam, Mobius or whatever else is appropriate.

Meanwhile, here is my best effort for that day:

https://youtu.be/qGWs9wMRk1U

8
Plans, Projects, Building and Flying Tips / The Utimate Hot Glue Hinge?
« on: February 06, 2020, 04:06:00 PM »
I have received the occasional respectful, even curious, comments about the hinges on several of my foam creations. Here is a video which demonstrates the technique involved.
The hot knife shown here is one I picked up at Michaels years ago. Note: Before venturing into that place, go to their website and you may be able to grab a coupon to save, say, 40% or so. To make my knife more versatile, I have a standard light dimmer ahead of the hot knife itself. That allows some degree of control over the heat output. When cutting foam with a hot knife, you may choose to use a steel rule or thin plywood piece as your straight edge. Using a wooden guide, the temperature may not vary as much, especially during long cuts, as the wood is an insulator whereas the steel rule is conductive and will be cooling the blade.

https://youtu.be/GrYaB9mZi8g

9
VIDEOS and PICTURES from KRCM Events and Activities / Tree Cub !
« on: February 03, 2020, 07:43:57 AM »
How does this thing keep on going? No one really knows, although Harold thinks he does. The poor thing has spent a couple of months in a tree overlooking Deseronto harbour, has had more scares than a little kid on their first Hallowe'en night, has had several of its wigglers replaced, a never-ending stream of hot glue, a major fracture of its wing, layer upon layer of "cosmetic" paint, casually thrown into the back of its owner's Fix Or Repair Daily (FORD) truck, etc. Yet, it just keeps coming back for more!

Have a look:

https://youtu.be/EP7C-4iL49Q

10
Well, after some trials and tribulations, I really have gotten the Sonic HD sorted out. Short version is that I bought it bare bones, stuck in a motor that I had lying around that looked like it might be suitable, ended up stuffing two 2200 mah batteries up front to give a reasonable G of G and went flying last March.

This plane is a beauty to fly. As others have previously found, it can be a real bitch to launch. Same here! Many disastrous launches, with and without stabilizer, lots of repairs to nose cone (it comes with a spare, plus the clear one for FPV, if desired). I got fed up, so I hung it up in the Cave until a week ago, then I suddenly decided to either scrap it or try something completely different.

I put a much smaller motor and prop, single 2200 mah battery, a little 30g weight up in the nose and gave her a fling. Excellent! A fluke? Let's see ...
try again ... and again ... Yay! Outstanding. no need to even enable the stabilizer for launches.

Many flights later, this as become my latest declared "favorite" airplane. Another is now on order from Banggood ... just in case.

Meanwhile, I am back to doing lots of videos. Some time ago, I mounted the Sony Handycam on a hard hat and that worked out fairly well. So, what about the Mobius? I stuck a piece of Velcro onto the peak of one of the dozens of baseball caps lying around home. The Mobius lines up exactly where I am looking and the video is far more stable than any handheld arrangement I have tried. I wish there was a zoom feature, even 2:1. but you can't have everything. Alternatively, I wish that Openshot, the video editor I use, could do a digital zoom processing; there was a claim that it can, but I have not found out how, at least so far.

Here is a bit of footage of my "favorite" plane in action at the Toyground on a beautiful winter day:

https://youtu.be/_C6f9FtDuOA

11
Plans, Projects, Building and Flying Tips / Magic repair stuff
« on: January 26, 2020, 06:02:13 AM »
I just came up a wonderful idea! At least I think it is  original, but it could be a latent memory, I suppose. I think I deserve the Nobel "Piece" Prize for this (little pun there, in case you missed it).

I had a plane that encountered a hard object and suffered scraping and gouging outboard on the wing. Some bits of foam were missing or permanently compressed, so it would require building up with something that was strong, light, sandable and paint worthy.

Two materials: light spackling compound and polyurethane glue (Gorilla glue or other brand). Spackling has water in it; water is the accelerant and foaming agent for polyurethane glue. A perfect match.

Put a dab of spackling onto something. Add a drop of the glue. The ratio is minimal glue to spackle. Mix thoroughly. Apply to the affected area with a spatula, broken prop or credit card, squeeze it into any crack and build it up just a bit for now. Do not be overly generous, as this mixture will expand somewhat. You will have a few minutes of working time before the mixture starts to stiffen.

Wait a few minutes. Notice the expansion. Go back and press it down some, it takes awhile to become really hard.  Don't worry about getting things perfectly even. 

Now, or perhaps in a little while, make up another small batch. Apply it to build up more, if needed. Again, wait, etc.

After the repaired area is filled, it will be easy to slice and/or sand off any excess. Apart from slight colouration, the repaired area can be perfect in appearance and strength. Paint adheres to it. It is at least water resistant, if not 100% waterproof (if you dunk your plane, it should not matter, just don't expect it to sit submerged overnight and be OK).

This repair sets much quicker than spackling by itself and it is stronger than just spackling, my usual repair material, and neater than gobs of hot glue.

This is a great way to repair foam, balsa, etc. Easy to work with and quite strong  - stronger than the surrounding foam.

My first run at this restored a really nasty looking wing to virtually new appearance, especially after a little paint. Only I, or the tree monsters, would be able to see the repair.

When you have idle time, experiment a bit with this so that you are confident and prepared to use it. Or, just fly properly and watch out for those pesky trees.  ;D

12
Whew! What a busy and exciting time out at our favorite Toyground. The Numb Thumb Flyers really flew up a storm the other day, I collected a lot of video and finally got around to cobbling together what I think are the better parts. Here it is, even though it ended up too long for me to expect that anyone will watch it all! (Well, perhaps Reg will, as he makes sporadic appearances from time to time in the collection. The guy sure packs in a lot of activity when he shows up here.)

https://youtu.be/_zH677hHGjw

13
VIDEOS and PICTURES from KRCM Events and Activities / The Swan
« on: January 20, 2020, 06:31:32 AM »
My latest "seamonster" is the Swan, which was test flown a couple of days ago. This is a really simple and quick build which turns out to be a very nice flyer without any bad manners. If the sun ever returns to the Great White North this year, we will see how these do in their alternate environment, water.
I had a 40-sized Seamaster for close to 20 years and it spent a lot of time flying from water and snow. In fact, it became my favorite winter plane for a long time. The Swan, loosely based upon the Shrimp, certainly bears resemblance to the Seamaster (no T-tail, though) and flies much like it. Here is an attempt to produce a semi-serious documentary on the Swan. Despite the heckling from certain members of Vultures Row, this went well. I have a lot of video clips taken that day of various activities that the Numb Thumbs Flyers were up to, which I hope to cobble together very soon.

https://youtu.be/93N62YTdc7Y

If anyone is interested in building one of these, I have a simple plan and PDF available. The latter may be publisher in here after I spruce it up a bit and encorporate a couple more details.

14
VIDEOS and PICTURES from KRCM Events and Activities / The Aero 120
« on: January 17, 2020, 02:27:09 PM »
Here is a sort of backgrounder video comprised of some clips I shot this Summer. I never managed to get video of the plane in flight; hopefully, we can get out there soon and do that. The Aero 120's ancestors stretch way back, perhaps 25 years. Seven 40-size glow versions emerged, each one slightly different, both low wing and high wing types. Dwayne took my plans and built the 10th one (this 120-sized one being #9 in the family) and has powered it with electric motor. He has the wing from my original plane, plus the one which he built. The latter was expanded by 1 bay to yield what he considers to be a somewhat slower and perhaps more sedate flyer. To each his own!

https://youtu.be/9Ye4Iw9W6rM

15
I cobbled together some video clips that were lurking within my Handycam. This was an perfect flying day, nice group of flyers and guests, some other observers dropped by, hamburgers were devoured. Our thanks to Jamie and Walter for arranging this!

https://youtu.be/tr5kAFrVTC8

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