General Category => Plans, Projects, Building and Flying Tips => Topic started by: Flypaper 2 on July 23, 2014, 11:30:58 AM

Title: Hints and Kinks
Post by: Flypaper 2 on July 23, 2014, 11:30:58 AM
 If your too lazy to go to the hobby shop like me, grab one of the antennas from your old 72 transmitter and put it through the bandsaw or hacksaw. You'll end up with a bunch of 7 1/2 in. chrome plated brass tubes of different sizes that fit nicely into one another.
    If you have more ideas for hints and kinks, put them up here. Maybe make it into a Stinky, or is that Sticky, at the top of the page. ;D
Title: Re: Hints and Kinks
Post by: ganguy on August 01, 2014, 10:31:48 AM
Heck, i was wondering what to do with that old 72. Now I know! The real question here is how did you find out?
Title: Re: Hints and Kinks
Post by: Flypaper 2 on August 02, 2014, 10:30:39 PM
I needed a brass tube for my gyrocopter rotor and didn't want to drive all the way over to the hobby shop for an inch of it. Looked around and saw this tube disguised as an antenna staring at me. :o A touch with the bandsaw showed me a bunch of different sized 6 inch chrome plated tubes. ;D Pays to be a junk collector sometimes. :laugh:
Title: Re: Hints and Kinks
Post by: ganguy on August 28, 2014, 02:17:05 PM
LIPO recovery:
The best hint you gave me Gord was how to resuscitate a dead LIPO. I had 5 in the morgue, and was able to get two up to full status, and on the others, I can save two cells each for the smaller planes. As they are all different manufacturers, I can't combine cells to make new 3 cell batteries.
You might want to repeat that process here for others.
Title: Re: Hints and Kinks
Post by: Flypaper 2 on August 29, 2014, 10:09:30 PM
Will do Reg.
 If your batt gets too low for the charger to read, Put it on NiCad or nimh until it reads just over 3 volts per cell. then put it on lipo. Watch the voltage carefully as it doesn't take long for the voltage to rise. Put it on balance charge.
Title: Foamology 101 - my glue gun mod!
Post by: Deerslayer on February 09, 2015, 06:58:58 PM
Since I enrolled in the Flypaper College of Aero-nut-ical Knowledge, I have been learning a lot. Just recently, I made a modification that greatly improves my gluing proficiency (Yes, Master, the Grasshopper is gradually improving):

Although I initially did this on the Alene glue gun, using one of its supplied detachable tips, it can be done on any gun. For example the attached picture shows my ancient $5 modified glue gun.

1. Get a piece of copper fuel tubing (we slimer drivers always have chunks of lying around).
2. Remove the existing tip tubing from the gun. You may have to drill it out.
3. Drill a new hole to enable an interference fit of the new fuel tubing.
4. Cut the fuel tubing such that it will project perhaps 1/2" or more longer than the original. One end will be a straight 90 degree cut, the other will be at, say, 30 to 45 degrees, approxinately. (the Flypaper TLAR method).
5. Clean up both ends, removing any burrs, inside and out. Clean it up with steel wool or such. Outside edges should be chamfered or rounded.
6. Force fit the new tube into the head. If the head is detachable, use your drill press. If you cannot force fit the tubing, drill a slightly larger hole, fit the tubing and use some JB Weld to secure it (Harold Jaeger's idea!). The JB is not softened at the temperatures present in the glue gun nozzle and insulates it to a great degree, as well.

You want the slanted end on the outside, of course, and it should be oriented properly - hold the gun normally, so it would lie against the object being glued.

Since this is now a longer tube, you can more easily reach into many areas. The longer copper tube MAY lose a bit more heat than the original. On my original Alene mod, I wrapped a few layers of the Teflon plumbing tape around it, up to near the end, as an insulator. This may also save some foam damage when you are tooting around in a confined space. (No need to do this if you applied JB to cement it all in place and to build up the protective layer as shown in the picture.

I find that I can make very small, strong joints, no excess glue and very quickly. It works well to run a fast little bead along a hinge line, then scrape the excess off by running a popsicle stick, credit card or piece of cardboard along that line.

Bonus tip: Yesterday, I picked up another glue gun at Michaels. Applying their 40% off coupon that came in the weekly flyer, the thing cost me $2.70, tax included!
Title: Re: Hints and Kinks
Post by: Deerslayer on November 11, 2015, 10:00:18 AM
The following video comes courtesy of the fellows at Flite Test. Is it required viewing for anyone who plans to attend the Flypaper College of Aero-nut-ical Knowledge, and it is pretty darn useful to mere mortals who fancy messing around with the stuff. Please enjoy:


 For me, the most valuable and frequently used trick with hot glue is the use of rubbing alcohol to break a hot glue joint without damaging anything. Just apply liberally to the glued region and start prying. As you peel away the glue, keep the interface wet. The alcohol wicks into the joint, vapourizes and releases the bond. You can easily clean up a servo, foam or other item that was all gunked up with old hot glue.

 The alcohol will not damage anything that I have worked with so far.

 If some glue is left, don't worry, just re-install whatever you need and the new glue will meld with the old stuff.
Title: Re: Hints and Kinks
Post by: ganguy on November 12, 2015, 09:37:33 AM
I was hoping to graduate this year from the FCAK, hope this will help. I've got about 6 wrecks awaiting hot glue magic. In fact, my whole fleet is down except for the SU27.
Now that trick with the alcohol is interesting, I'll try it, but can you use the drinking stuff too? Imagine the smell of a vodka-soaked Pitts!
Title: Re: Hints and Kinks
Post by: ganguy on November 12, 2015, 10:22:50 AM
After watching the video, I found the best trick (after the alcohol trick)  to be the edge-sealing with a notched piece of foam board. Otherwise, the rest I learned at the FCAK in Hot Glue basics, otherwise known as HG 101
Gary - what is the longest tip mod using fuel tubing? Sometimes I'd like to get 2-3 inches for repairs inside the fuse.
Title: Re: Hints and Kinks
Post by: Deerslayer on November 12, 2015, 01:28:44 PM

Gary - what is the longest tip mod using fuel tubing? Sometimes I'd like to get 2-3 inches for repairs inside the fuse.

I used about 1 inch extension from the base. I wrapped it with some layers of Teflon tape, tapering down to near the tip, figuring that this would prevent excess heat loss. I seems to work OK. If I let the thing sit for awhile under power, the glue inside the tip section may turn brown and/or become less useful. So, I do a little squirt of glue, then wipe the tip prior to using it.

Caveat: This whole approach is NOT YET approved by the Master and therefore cannot yet be added into the HG 101 curriculum at the FCAK. Employ at your own risk. And, do not even think of suing me if it all goes into the dumper...
I know some very nasty folks who are always looking out to make a little "contract" money, if you know what I mean.
Your friend, Gary.

A friend will help you.
A good friend will help you move.
Your best friend will help you move a body
Title: Cable Tie Hinges
Post by: Deerslayer on January 02, 2016, 11:43:06 AM
Cable Ties come in various sizes and are excellent to make hinges from.  Such hinges can be used, as in the example shown, to make interplane struts for a biplane, or for regular control hinges (either on the surface of $Tree foam or into drilled holes on balsa or heavier foam). Attached are some pictures of my technique.

 1. Take a small piece of 1mm or so control rod. Lay the cable tie on the bench, smooth side down and then lay the rod across it.

 2. Clamp down the combination with the vise grips, having previously adjusted them so that the rod will squash down the cable tie hinge location. This may take some trials to decide upon the exact amount.

 3. Remove the vice grips and snip your hinge to appropriate length. Work it back and forth a few times, you should feel it become more flexible.

 The hinge can be attached with hot glue, polyurethane, almost anything that will stick to the thing you are attaching it to. The ribbed side provides an excellent grip.

 This material is essentially chemically inert, so you want a clean mechanical bond. I take some acetone and wipe the hinge and, in the case of carbon fibre or metal, I wipe that surface as well.

 Since you are not cutting the material, just plastically deforming it, it should not break in reasonable use. No guarantees, just my personal opinion! Your mileage may vary.

 This message is brought to you, and approved by,
Foamology Department
Flypaper College of Aero-nut-ical Knowledge
 "Conquering the skies one glue stick at a time."
Title: Re: Hints and Kinks
Post by: Deerslayer on January 02, 2016, 06:39:47 PM
  On my little homebrew, sort-of-Flypaper style biplane, I needed to install something to lock on the wheels. The heads of cable ties work admirably! Being a cheap SOB, I have a collection of slightly used cable ties of various sizes in my pile of treasures. You just press the head onto the axle, snip off the strap and voila, a surprisingly secure yet removable wheel retainer. No need to waste precious coin on little wheel collars and battle with tiny, crappy hex keys.

 Penny Tech rules!  ;D
Title: Re: Hints and Kinks
Post by: ganguy on January 23, 2017, 03:12:43 PM
I like that one, Gary. Once you did a bit on making dummy cylinder heads, where can I find that?
Title: Foamy Hinges
Post by: Deerslayer on January 12, 2019, 09:30:06 AM
As I prepare my latest store-bought foamy for flight, I would like to pass along something which I only learned perhaps 4 or 5 years ago and which may be news to some others.

Many foam planes come with foam hinging for the control surfaces. This kind of thing is very strong, sometimes extremely stiff to bend.

 It can become reasonably flexible - if you prepare it properly. Do not think that you have to haul out the knife and start slicing at the hinge, or chop the control surface out in order to re-hinge with (dog forbid!) CA hinges or even Robarts-style pin hinges. I have many hours of hard flying on a number of planes with the original hingeing and no breaks.

The trick is to "season" the hinge.

1. If the controls are already hooked up, unhook the control rod from the surface to be worked on.

2. Work the control surface slowly and gently, back and forth, perhaps half way to their extreme positions. You do not want to tear things apart. Do this a few times.

 3. Then, gradually increase the movement to reach the extreme positions, cycling it slowly a dozen or more times.

4. The hinge is now through its initial break-in. You can continue this deflection more rapidly, Don't go overboard on this and rip things apart!
Do this dozens of times. Some say a hundred - it can't hurt.

You now should have a very strong, yet flexible, hinge that will not unduly load your servo and still resist any tendency to flutter.
In some cases, such as a couple of sailplanes that I own, you will find that the hinge line is at the top (probably)  or bottom (not likely) of the interface between the structure and the control surface. In that case, at perhaps Step 3, you may wish to bend it all the way up and prop it or tape it in place overnight. The hinge will relax into that position and you will find that it becomes even easier to achieve full deflection up and down.

Good luck!
Title: Prop Stopper
Post by: Deerslayer on January 29, 2019, 08:49:50 AM
No! Not your fingers!

This can be useful on flying wings with pusher prop arrangement or on any plane where you want the prop to stop at a specific orientation, e.g.,  when you mount a camera up front and do not want a dead or windmilling prop to be blocking the view.

Take a piece of nylon monofilament (weedeater wire) and punch a hole through the foam such that it can project out just past the prop or be fully retracted away from the prop. Use a cheap servo, as there is no force involved here. Now, when the motor is powered off, your prop stopper can be advanced and the windmilling prop should come to rest aligned in an approximately horizontal position.

But, we don't want to simulate the old "playing card in the bicycle spokes" deal, do we? (Really, really old guys may still remember when that was part of our youthful entertainment as street urchins). So, what I do is to have my Lockout switch activate the prop stopper. On the DX9, I set the servo speed for that channel such that it retracts the stopper at normal speed but the activation is done at slower speed. That probably does not matter, but seems like a good idea to give the prop a short time to freewheel and wind down after chopping the throttle, plus it is a trivial thing to set up, so why not do it. You could also set this up to activate via your Throttle stick (use Digital Switch Setup on Spektrums), triggered when it is pulled fully back/off.

Note that I mention the Lockout switch. Of course, we all employ the normal Throttle Cut (if you don't you should not be flying!). All of my planes have an additional switch set up to accomplish the same thing, as has been recommended and posted elsewhere in our Forum, at least for Spektrum and Graupner systems. That way, an unintentional bump or such of the normal Throttle Cut switch will not allow power to the motor unless this Lockout switch also allows it. I set both switches every time I pick up a model which has a battery in it, or I am about to plug in a battery or when I work on it on the bench - unless I forget, in which case perhaps at least one of the 2 switches may be in the Safe position.

I have, or have had, a lot of flying wing and delta style planes. Whether they be pusher or tractor prop setups, it would be nice to count on landing with the prop horizontal. Honestly, I have never broken a prop on landing one of these planes, regardless of prop orientation. I do not use a rubber band "prop saver", The only time I ever lost a prop was on the one plane where I had use this so-called "prop saver" - the prop is still out in the wilderness somewhere, being "saved" for the mouseys to nibble on, I suppose. :'(

On most landings with a pusher flying wing, the prop will tend to spool down and line up with the wing if the plane is slowed at the right rate. Sometimes, you can help it by doing an abrupt pull up or even jogging the the throttle later on as you approach the landing. Even if the prop is not horizontal but is still moving, it will nudge into position as first contact with ground is made - unless you manage to really slam it down, tail low, I suppose. Just watch out for those really high alpha landings where it falls out of the sky at zero groundspeed, prop first!  :o