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Hobby UAV
21st January 2014, 03:04 PM
I originally designed the techpod with the intention of flying it around 4.5 lbs and a cruise speed of around 30 mph. However everyone wants to fly faster and longer, myself included. Along with the fact that control loss is quite frequent when performing long range FPV flights. This has led to weights in excess of 7 lbs and speeds in excess of 65 mph being achieved in an uncontrolled dive. This has led to catastrophic wing failure.

In an effort to modify the techpod to handle the higher loads and higher speeds, I have began this thread and will be posting pictures of my progress and testing. The goal is to come up with a upgrade kit for anyone who needs something a little tougher then the stock techpod.

first I installed some plastic tubes so servo wires can be installed after the wing is complete. I used goop on the spar and CA on the foam to foam areas.
http://hobbyuav.files.wordpress.com/2014/01/img_07501.jpg?w=600
http://hobbyuav.files.wordpress.com/2014/01/img_07511.jpg?w=600

I attached the two basswood pieces using some gorilla glue.
http://hobbyuav.files.wordpress.com/2014/01/img_07581.jpg?w=337

next I removed the control surfaces. I cut the wing so a couple of 1/2 x 1/4 x 24 inch pieces of basswood a can form a new flap hing line.
http://hobbyuav.files.wordpress.com/2014/01/img_07561.jpg?w=600

I drilled out the spar to accept a 7 inch piece of brass tube.
http://hobbyuav.files.wordpress.com/2014/01/img_07541.jpg?w=600

the Brass tube slides in and will form a sleeve for a steel connecting rod.
http://hobbyuav.files.wordpress.com/2014/01/img_07522.jpg?w=600
http://hobbyuav.files.wordpress.com/2014/01/img_075311.jpg?w=600

after some trials and tribulations, I came up with molded corbon fiber wing skins.
http://hobbyuav.files.wordpress.com/2014/02/20140201_112203.jpg?w=337

Derrick
21st January 2014, 03:50 PM
Due to the high aspect ratio wings and relatively thin airfoil section, your best "bang for the buck" upgrade is going to be to the "skin" of the wing. The ideal solution is to vacuum bag a fiberglass skin with unidirectional carbon reinforcement (though this is something that an average modeler can't do). The next best option is to add ribbon spars top and bottom in addition to laminating the entire wing (this will add bending stiffness from the ribbons and torsional rigidity from the laminate). The second alternative is something that any modeler should be able to do. It is also effective cost wise too.

Check out the build instructions for a windrider bee to see how to effectively ribbon spar a wing.

Hobby UAV
21st January 2014, 06:00 PM
hey Derrick, I am going to try something like what airtruck has going on.
http://i1194.photobucket.com/albums/aa371/airtruksrus1/Techpod/image-8.jpg
plus I want to expand on his idea with laminate top and bottom on the root.
http://hobbyuav.files.wordpress.com/2013/12/20131130_151130.jpg?w=337

Hobby UAV
22nd January 2014, 10:58 PM
so I spent the day making a box so I can heat up the wings while they cure. an electric blanket gets it up to 110F. I am aiming for 125 so i will try adding some insulation tomorrow.
http://hobbyuav.files.wordpress.com/2014/01/img_07621.jpg?w=337
http://hobbyuav.files.wordpress.com/2014/01/img_07631.jpg?w=600

The plan is to laminate some 5 OZ CF cloth to the to and bottom of the inboard half of the wing. this is a paper pattern I made to help cutting out the CF.
http://hobbyuav.files.wordpress.com/2014/01/img_07601.jpg?w=600
and here is the CF cloth
http://hobbyuav.files.wordpress.com/2014/01/img_07591.jpg?w=600

airtruksrus
23rd January 2014, 01:47 AM
I took a good look around different curing techniques and different brands of resin and the variety of curing temps landed to the same conclusion, as long as it's not too hot of a batch and if setting a curing temp that it doesn't compromise the integrity of the foam, you should end up with a good layup. Are you making a shell or using an epoxy based adhesive to attach it to the wings?

All the wrap of the wings should maintain a really stiff wing as I found another defect after many landings on the older Techpod. I finally gave up the reigns and let a friend of mine launch it for me, unfortunately he launched it at a climbing angle and lost too much airspeed then stalled with a rough landing. Had one good flight before this. Where the weak spots came up was the forward inner corner of the flaps on both wings, developing cracks at that same location. The lamination stopped it from spreading further forward but a question of more flex in the wings. Probably time to move into the new one as the motor mount also suffered from continuous flexing and didn't take much for it to snap at the bottom where the holes are drilled for the lower motor mounts. might need to use a sturdier material to reduce the operational stress. I have some 1/8" fiberglass plates that I can cut out using the original piece as a template, they should be light and resilient to withstand the rigors of continuous flights. I looked at it further and looked like it weakens up from repeated twisting and eventually gets looser. Hope it helps and looking forward to seeing the new updates on the kit.

Hobby UAV
23rd January 2014, 02:52 PM
Ok thanks Scott. I have some 1 - 8th fiberglass as well. I will see if my home made cnc machine will handle it. The flimsy 3 ply plywood they sent with the kit really start to fall apart over time. If my machine can't handle the FG, I may try laminating CF cloth over some 5 ply aircraft grade plywood.

Here is the heat box all insulated.
http://img.tapatalk.com/d/14/01/24/5ypyba3y.jpg

If you could post some pictures of the flap area cracks and engine mount I would appreciate it. Ty!

Hobby UAV
23rd January 2014, 03:12 PM
I think the way I am putting the second spar just in front of the flap, should prevent cracking in that corner.
http://img.tapatalk.com/d/14/01/24/uhutyve7.jpg

Hobby UAV
23rd January 2014, 03:58 PM
So here are the CF darts and kevlar leading edge.
http://img.tapatalk.com/d/14/01/24/vydyse3e.jpg

airtruksrus
23rd January 2014, 04:37 PM
Wayne, the laminate did the job of holding the foam together but the stress from the hard landing is what cracked it and stretched the laminate enough on both sides.
http://i1194.photobucket.com/albums/aa371/airtruksrus1/Techpod/image-17.jpg

The strengthened up motor mount should fix any stress problems from occurring again. Was kind of strange that the motor was oscillating back and forth during regular flying but didn't break until the motor was running full throttle when it landed, not any more stress than it usually goes through.
http://i1194.photobucket.com/albums/aa371/airtruksrus1/Techpod/image-18.jpg

Hope it helps. I could probably continue to try to repair it further but after looking at the rest of the structure, probably best to move it to the improved airframe. It should hold up much better, just surprised that this one survived as much as it did, one amazing and tough airplane. Was also considering adding a single wheel down the centerline and pull pull control for the rudder.

Hobby UAV
23rd January 2014, 05:17 PM
Cool thanks. I was considering whether to vacuum bag the CF directly to the wings or to make the CF into plates to be wrapped after they are cured.

Vacuum bagging the CF to the wing would probably give the best bond, but if I make some plates cut to size, people who have the kit already can apply it and it would be less expensive and time consuming.

I'm going to try the pre cured plates first I think.

Derrick
23rd January 2014, 05:32 PM
You can make precured plates using a vacuum bag and a section of wing... your layup will look something like this:

Bag
breather
waxpaper
carbon layers
waxpaper
wing
breather
bag

It will be much harder than you think to get flat plates to conform to the airfoil after they are cured and stay in that shape over time. Looking forward to seeing your product.

D

airtruksrus
23rd January 2014, 05:56 PM
That was a big problem I found and stuck using the laminated plate for flat surfaces. I try to use a slow cure epoxy with the carbon cloth if I use it to wrap compound surfaces, just need to supply a small amount of heat from the space heater in an enclosed area to have it cure within a reasonable amount of time. The wax paper works good, I've got some Sig mold release wax that closely resembles clear shoe polish wax. Works great when fabricating the carbon plates between two sheets of aluminum, compresses it nicely.

Hobby UAV
23rd January 2014, 09:19 PM
Ok I just got back from tap plastic. Got some PVA and carnauba wax. I will try doing it over a actual wing. If I like the results, I can make a more formal mold.

Hobby UAV
24th January 2014, 06:18 PM
Ok I threw some 1/8th G 10 on the cnc and this is what I came up with.
http://img.tapatalk.com/d/14/01/25/y2yba9em.jpg

It cut pretty well. I am going to cut out the rest of the bulkheads and the spar box.

Hobby UAV
25th January 2014, 12:01 AM
so i bagged up a wing. its cooking in the cure box.
http://hobbyuav.files.wordpress.com/2014/01/img_07641.jpg?w=600

I also cut out a set of bulkhead, motor mount and spar box parts. turned out pretty good.
http://hobbyuav.files.wordpress.com/2014/01/20140124_195712.jpg?w=600

airtruksrus
25th January 2014, 01:46 AM
Looking really great, would almost bet the slight gain in structural weight would be insignificant to the longevity of the life of the airframe. As long as the surface is prepped right, that foam should stay put for a long time.

Was able to mount the wheel support to the bulkhead that holds the spar clamp using a nose wheel bracket, rests on the c/g. Should protect the bottom and allow takeoffs from the runway.

http://i1194.photobucket.com/albums/aa371/airtruksrus1/Techpod/image-19.jpg
http://i1194.photobucket.com/albums/aa371/airtruksrus1/Techpod/image-20.jpg

Hobby UAV
30th January 2014, 12:51 AM
I had quite a bit of issues trying to mold skins. Wax paper definitely does not work well. Molding over the foam wings was a disaster
http://img.tapatalk.com/d/14/01/30/6eju3uda.jpg

I cut out some butter board I had with the cnc. The mold came out very good.
http://img.tapatalk.com/d/14/01/30/aza6amav.jpg

I am going to attempt to mold some skins over this tomorrow.

Carbon
30th January 2014, 10:19 AM
This thread is funny. "I sold an FPV plane that isn't suitable for FPV, here's how you can fix it."

Hobby UAV
30th January 2014, 11:00 AM
Actually I should name it "how to make a piece of foam do the impossible"

Sicarius
30th January 2014, 11:52 AM
This thread is funny. "I sold an FPV plane that isn't suitable for FPV, here's how you can fix it."

I think that's an unfair statement.. If a plane isn't built for 70 mph dives then it simply isn't built for it, when control is lost, it's still at the pilot's discretion, as it's probably an error in installing the equipment.
If I take my Z2 out in a full throttle dive and i slam the elevator, it probably folds in half.. You won't see me taking it out on Chris, but on myself :)

Derrick
30th January 2014, 12:27 PM
This thread is funny. "I sold an FPV plane that isn't suitable for FPV, here's how you can fix it."


I think that's an unfair statement.. If a plane isn't built for 70 mph dives then it simply isn't built for it, when control is lost, it's still at the pilot's discretion, as it's probably an error in installing the equipment.
If I take my Z2 out in a full throttle dive and i slam the elevator, it probably folds in half.. You won't see me taking it out on Chris, but on myself :)

I agree with you that an aircraft has a flight envelope and should be flown within it, however with respect to the design of this particular aircraft the focus was aerodynamics and efficiency. Mechanical structure and durability were put on the back burner and as such this thread was created. Design is a series of compromises, when you drift to far in one direction you have to give in the other...

Hobby UAV
1st February 2014, 01:19 PM
I in no way put "Mechanical structure and durability were put on the back burner ". I designed it with a particular VNE in mind. While remaining in that VNE of about 50 mph, my tests and experience showed no signs of wanting to break.

I completely apologize for not understanding 65 mph dives and emergency pull ups where expected to be survived. That simply was not part of my original design criteria. my inexperience with long range FPV left me unaware of the many time out of control situations that can arise.

I also apologize for not coming up with an upgrade earlier. Work and keeping up with customer service and having a family life left me with no time. To that end I quit my job so I could have the time to do this:
http://hobbyuav.files.wordpress.com/2014/02/20140129_132626.jpg?w=600
http://hobbyuav.files.wordpress.com/2014/02/20140201_082810.jpg?w=337
its 5 layers of 3.5 oz CF at the root 2 layers at the tip. The finish is no good but i know what went wrong and how to fix it. ill trim it up and see how it fits.

Hobby UAV
1st February 2014, 03:40 PM
the skins fit perfect after a quick trim.
http://hobbyuav.files.wordpress.com/2014/02/20140201_112203.jpg?w=337

the leading edge looks good. a quick sanding and it should mate perfectly to the bottom half creating a nice sharp LE.
http://hobbyuav.files.wordpress.com/2014/02/20140201_112312.jpg?w=337

airtruksrus
1st February 2014, 04:07 PM
Glad to see it coming along, most of the carbon cloth projects didn't look that great popping out of the mold. The best finish I attained so far was on my mustang hood scoop using wax paper over the layup and squeegee out as much resin as possible. The carbon weave turned out really consistent, even after 2 or so years with acrylic enamel clear coat.

5 plies should be very stiff on the wing. Was considering using the lite glass with all of the carbon strand already laid out. Might use the older wings for a test subject first.

Hobby UAV
1st February 2014, 04:22 PM
I used mylar and I laid up on the mylar not the mold. I think a little more epoxy directly on the mylar and even let it set up a little before laying the first layer of cloth down.

airtruksrus
1st February 2014, 06:03 PM
Are you going to the r/c expo in Monroe next weekend? Trying to get over next Saturday, figure its just down the road from you.

Derrick
1st February 2014, 06:12 PM
I in no way put "Mechanical structure and durability were put on the back burner ". I designed it with a particular VNE in mind. While remaining in that VNE of about 50 mph, my tests and experience showed no signs of wanting to break.

I completely apologize for not understanding 65 mph dives and emergency pull ups where expected to be survived. That simply was not part of my original design criteria. my inexperience with long range FPV left me unaware of the many time out of control situations that can arise.



I did not intend to offend you wit my previous post, rather point out to Carbon that design is a compromise. You must give and take to come up with a solution. In the case of the techpod emphasis was given to efficiency, thus stiffness and durability were diminished.

Hobby UAV
1st February 2014, 06:53 PM
Non taken ;-)

Hobby UAV
5th February 2014, 09:59 AM
All 4 skin molds are done. I have to prepare the molds today . I should be done with the molds and have the first batch of skins tomorrow. I can't wait to test the new set up.

BCSaltchucker
8th February 2014, 05:19 PM
If I take my Z2 out in a full throttle dive and i slam the elevator, it probably folds in half.. You won't see me taking it out on Chris, but on myself :)

well not the right comparison here. I bet your Z2 would do it no problem unless it is running 1000 watts. I do that with my Z2 all the time. Even my Teksumo. These wings are meant for radical flying.

It is fair enough that the oem Techpod must be flown within a tepid envelope. Can set up failsafes to keep it level and unstressed with RC control loss, and avoid cumulonimbus too.

That said, I am beginning the process of HDing mine now. Wow I ran out of epoxy real fast doing this. Need to buy it in litres I think

BCSaltchucker
9th February 2014, 04:19 AM
Hey I have a Q for the aeronaut engineery types. Where would ribbon spars be more effective? On the top of the wing, or on the bottom? And don't say both, that's cheating :D

Flying Monkey
9th February 2014, 11:21 AM
Hey I have a Q for the aeronaut engineery types. Where would ribbon spars be more effective? On the top of the wing, or on the bottom? And don't say both, that's cheating :D

You really do want both... but, the bottom would be better, because the foam can take compression and resist compression (as long as you don't mind a bendy floppy wing) but putting the spar on the top would mean that the foam would be in tension and could split apart, then putting all the force on the spar which would snap it quickly.

It's best on top and bottom. Because in a foam wing, the top spar is in compression and the bottom is in tension, while the foam acts as the "webbing" like in an I-beam to help keep the two spars from splitting apart, or from compressing together. Usually the tension can handle a LOT more load than compression, like guy wires or suspension bridges can use relatively tiny wires to support huge heavy structures. But that doesn't mean you can have 2 spars on the tension side and only one on the compression... It actually means you need to do the other way around. You could have a single 2mm carbon fiber rod on the bottom, but would need two or three 2mm rods on the top, otherwise the top will buckle LONG before the tension side rips apart. Course if you're doing aerobatics, inverted flight... then keep it equal top/bottom but you need to have BOTH have the two or three 2mm spars, or maybe go up to a single 4mm rod. Actual size will vary once you're doing the math on the loads expected of course ;)

http://www.teachengineering.org/collection/cub_/lessons/cub_images/cub_mechanics_lesson10_image3.jpg

Also... you may see that the center of the I beam does very little, its in the neutral point between compression/tension loads. That's why you often see round or triangular hoels cut out the webbing. And that's why it makes zero sense to add material to the middle, or fill a hollow carbon tube with material that's, lol, LESS stiff than carbon. And if a foam wing has single round carbon tube in the middle it needs to be as large in diameter as possible, to the point of almost popping out of the wing skin. If you have a 1" thick wing, and you put a 1/4" or 1/2" round carbon tube... facepalm!

http://www.zenithair.com/stolch801/gif/spar.gif

http://www.homebuiltairplanes.com/forums/attachments/aircraft-design-aerodynamics-new-technology/11538-monerai-spar-cap-analysis-monerai1.jpg

http://www.steelconstruction.info/images/thumb/0/08/Hayes_Garden_Centre.png/400px-Hayes_Garden_Centre.png

http://www.musictrends.com/images/I-Beam.gif

OtherHand
9th February 2014, 12:00 PM
As an engineery type myself, I must say that's an excellent lay person description. I've always held that a truly excellent engineer (and especially scientist) is able to explain complex ideas in a manner the average person can understand. Nicely done.

Hobby UAV
9th February 2014, 01:10 PM
Very good points. I put some thought into using .5 x .125 CF on the surface but having a flat spot on the airfoil killed the performance. The problem with just a larger tube is the foam and cord wise stress. The foam for one can't be molded with under 1/8th inch feature. So that limits how close you can get it to the skin. Second, the wing also experiences cord wise stress as well so if you use all up all of the vertical foam area at the spar, you only have glue holding the wing together cord wise. That is a big reason why you see thick airfoils used in foamies.

I have all 4 skins molded. They turned out pretty nice.
http://img.tapatalk.com/d/14/02/10/a4epe9er.jpghttp://img.tapatalk.com/d/14/02/10/y7eqeny9.jpghttp://img.tapatalk.com/d/14/02/10/y7e7azeq.jpg

I'll be putting together a Techpod this week with the G10 fiberglass bulkheads and CF skins. I will also be moding the tail and making a mold for a belly skid. It should be fun to fly I've got a high amp motor I'm going to strap to it.

airtruksrus
10th February 2014, 05:27 PM
Wayne, I got a really good look at some construction techniques used by the hand launch glider folks with epoxy glass over foam using a thick Mylar after application on the surface to result in a very flat and smooth surface with the spare epoxy squeezed out. Some of their lay ups had carbon cloth underneath the glass which had phenomenal strength. Might use some of the same processes for the build.

As a boost, I managed to get the new motor and all 6 servos to get it finished up after I get back from down south around the 9th. Decided to go with another 2820 out runner in the 740kv range to see if it will handle the larger folding prop with less current draw when at cruise. If the Rvosd issues get resolved this trip down using the Spirit glider, it'll go into the new Techpod when I get back.

Hobby UAV
11th February 2014, 11:36 PM
My personal favorite type of construction is stressed skin. I have implemented it here in this upgrade. The skinned areas are rock soild. span wise and cord wise as well as torsional stiffness is incredible.
http://img.tapatalk.com/d/14/02/12/evaqyjyv.jpg

I like the way it turned out. I just need to trim the excess glue and then do the other side in the morning.

Hobby UAV
12th February 2014, 08:32 PM
Ok both wings are done and the second connector spar is in. This thing is rock solid.
http://img.tapatalk.com/d/14/02/13/huqevegu.jpg

Hobby UAV
13th February 2014, 09:53 PM
Got it all together it's unbreakable, at least it will handle more load then the wing can provide. Pictures and video coming tomorrow.

airtruksrus
15th February 2014, 10:55 AM
Anxious to see the performance specs from this. The way its built it should handle a greatly increased cruising speed with very few issues. Put it through the rigors of testing and see where it gives. As long as the tail and control surfaces are good and solid, it should handle a full speed dive with a smooth pullout without effort.

Hobby UAV
22nd February 2014, 01:58 PM
I have the fuselage mostly done.
http://img.tapatalk.com/d/14/02/23/3aqajuvy.jpg

I added a 9 mm CF rod to the tail
http://img.tapatalk.com/d/14/02/23/e2upyhu9.jpg
I need to figure out the tail mount then I'll be ready to install the radio and get this thing flying.

Hobby UAV
6th March 2014, 02:19 PM
Working on the tail mount today. I have to say I absolutely love my replicator. Now only if I can get it to make me some earl gray tea.
http://img.tapatalk.com/d/14/03/07/ebymeve9.jpg

Blizzard1287
6th March 2014, 04:09 PM
lookin' good there Wayne.

airtruksrus
7th March 2014, 08:36 AM
Mmmm, earl grey....


Now if I can just finish up the new plane. Looking forward to seeing all the mods work.

Hobby UAV
10th March 2014, 05:18 PM
here is some cad of the tail mod I have been working on. I printed out a test yesterday but i need to make some adjustments.
http://hobbyuav.files.wordpress.com/2014/03/tech_tail_new.jpg?w=732

airtruksrus
12th March 2014, 12:48 AM
Has anyone asked about a full flying elevator yet. Was curious about changing out to use one to lighten up the tail and increase the pitch gain. Figure that this plane is more of a motor glider anyway and could also reduce a little drag, works great on 3 of my sailplanes and converted the Sophisticated Lady with much success.

airtruksrus
27th March 2014, 02:26 PM
Haven't heard anything going on in a while on the thread, Wayne were you going to head up to Mudlarks spring meet in April like last year? Would be able to bring the new Techpod with the mods but not flying yet until all the Rvosd settings are complete. I want it to stick around with less chance of problems. Bringing the trailer as well with basic functionality to do some flying from. Want to fly the Techpod out of this on a regular basis.

Hobby UAV
27th March 2014, 02:31 PM
Printing out some parts for the tail right now as a matter of fact. I've been deep in the lab. I will have a new cnc machine i need to fabricate the parts for the HD. It is supposed to be ready to be picked up tomorrow then i have to put it together. Got one from cncrouterparts.com they are located right here in North bend.

Hobby UAV
27th March 2014, 02:34 PM
Ya I'd love to go to mudlarks. Is there a date set yet? I'll have the hd flying in a day or two. I'll Post The Tail Mods In A Few

ChrisG
27th March 2014, 02:58 PM
Hi Wayne,

Hoping you can refrain from another attack on me like the one on diyd when I posted my 4+hr 203km flight.

I am NOT a John fanboy mate... Quite the opposite! I was just asked to do a review on the kit because I get the results... Nothing more.
After all I did buy one of your kits at huge cost and wait time to get it here in Oz, I just felt with its problems at the time it wasn't worth building it yet.

I'd like to honestly thank you for all the work you put into designing the techpod, it's a shame you n John split because his version of airframe has turned out quite nicely after a few little finishing touches.
Can totally understand why you split... I never want anything more to do with him but you really should take a look at what he has paid the guys to come up with in the spar design and boom/tail area and maybe "borrow" some ideas to return the favour.

Peace,
Chris.

airtruksrus
27th March 2014, 03:34 PM
Chris, I'd be interested if the spar changes were a little more resilient if you have any other info. I was going to go for the stainless steel rod again due to its inability to bend and building in the aft support for the wing again. That's a hell of a long stretch of distance on that plane, dam great job. Might keep hopeful in getting half of that when ready for flight.

Wayne, the meeting is set for April 12,13 - kind of an overnighter for those willing to camp out. Should be a good time especially if C5 shows up with his trailer also. Check the side chat thread, plenty of talk on it.

ChrisG
27th March 2014, 03:49 PM
Hi airtruk,

Thanks mate, it certainly was a big mission!
The other uses a very simple slightly larger telescoping spar system and a permanently mounted centre section and also a larger dia longer boom that aids flight characteristics so there would be some major mods to do but anything can be done if you're keen enough ;)

airtruksrus
27th March 2014, 05:34 PM
I was looking at ways to lighten up the tail a little bit. wanted to keep the Cg from requiring so much nose weight to balance it and might improve the handling as well. The older plane had so much happen to it, felt like I was flying while walking a tightrope with little room for error. This newer one should be a blast to fly, should be up around May if all works out. Too many projects on the front burner.

Hobby UAV
27th March 2014, 07:06 PM
Hey Chris,
I apologize for my reaction. I understand that you are not party to Johns actions. Personally I think John is doing his customers a huge disservice by creating this situation.

That aside, I do wish to make a few things clear:
#1 the techpod is a part of me, I would never give up on it or allow others to disrespect it.
#2 I borrowed my brothers solidworks. I didn't always have access to it. I just bought a copy of Rhino 3d and I am still getting used to it.
#3 I was working the night shift as a machinist in a very high demand field. 60 and 70 hour work weeks are common.
#4 I am busy raising a family of 4, my daughter went through a very rough period for the last 6 months with her arthritis. Thank God she is finally feeling better!
#5 I have been doing very well building RTF techpods. I get a lot of research institutions and universities. Hog hunting is huge in TX. I have not had a clear build schedule for more than a week on the last 6 months, very busy with that.

Thank you so much for giving me credit.

Hobby UAV
27th March 2014, 07:26 PM
So here is the new removable tail.
http://hobbyuav.files.wordpress.com/2014/03/img_0798.jpg?w=600
http://hobbyuav.files.wordpress.com/2014/03/img_0800.jpg?w=600
http://hobbyuav.files.wordpress.com/2014/03/img_0801.jpg?w=300
http://hobbyuav.files.wordpress.com/2014/03/img_0803.jpg?w=300
It seems very strong. doesn't add much weight at all.

Hobby UAV
27th March 2014, 08:03 PM
@ airtruck, want a tail upgrade kit? I can send you one for testing.
BTW here is my new baby. can't wait to get my hands on it!
http://www.cncrouterparts.com/images/PRO4824.jpg

ChrisG
27th March 2014, 09:41 PM
Thanks for that Wayne,
I am somewhat to blame for the Agro and fully understand you being upset given the circemstances.
Just wanted to make it clear I have nothing to do with ATD.. I even paid for my own shipping of my tester kit!

The other kit will have the same wing twist dramas too, I can guarantee it.
My strength secret is tying it all together properly and then clear taping the top and glass taping the bottom... I've scratch built lot of planes and have a good understanding of construction techniques with foam from ds/slope wings.

I'm just glad your pod design has achieved this flight and you should be proud of it as not many aircraft under 3kg tow could pull this off.

P.s very very jealous of your new Cnc ;)
Chris.

airtruksrus
27th March 2014, 09:48 PM
Alot of work going into the tail mod, it effectively turns the elevator into a bolt on attachment. Should allow you to change out the elevator in the unlikely event something happens to it during transport. I'm at the point still where the elevator isn't glued on yet, was looking into the flying stabilizer but if you need some testing done, I could speed up the build and get it ready with the Feiyu tech nav gear. It's sitting in a bag off to the side for the moment, the Rvosd takes a bit for me to go through all the modes to make it effective. It also looks like with the centerline wheel, it should prove valuable when flying out of the trailer, should feel like taking off with the U2. Have to see how far I can get before the meet.

Wasn't up to speed on what the issues were surrounding the other party, just a shame to hear the approach he took afterwards. Seems like things are looking better, especially taking it to a full time business.

Hobby UAV
27th March 2014, 11:08 PM
thanks guys! For now I am able to pay my share of the bills and get the equipment I need to start making some next level stuff. I'm not rich but I am doing what I love and I owe it all to you guys and even more my awesome wife. and that's really all that counts.

@ airtruck, ill print that out for you tomorrow and send it off. do you have some 9mm or 1/4 inch CF tube or something close? if you do then i can fit it into a small box. let me know what size you have so i can print to fit.

Hobby UAV
27th March 2014, 11:17 PM
here is a good picture of the top of the tail mod
http://hobbyuav.files.wordpress.com/2014/03/img_0799.jpg?w=600

ChrisG
27th March 2014, 11:26 PM
Very functional mods Wayne.
But I've always been a V-tail fan, had plans to make your original one a V from the start.
Majority of prop thrust gets blown between rather than straight into the stab/fin join ;)

Worth exploring at some stage, maybe lengthen the boom about 100mm too.

airtruksrus
28th March 2014, 04:22 AM
@ airtruck, ill print that out for you tomorrow and send it off. do you have some 9mm or 1/4 inch CF tube or something close? if you do then i can fit it into a small box. let me know what size you have so i can print to fit.

I looked around and found I still have a small length (12") of 6.5mm/ 1/4" carbon rod and 3 - 5.4mm carbon rods, used the other 6.5mm rods to add as stiffener inserts for the main spar. There is still the solid carbon rod you dropped off last time over if that will work.

Hobby UAV
31st March 2014, 08:48 PM
Ok got your stuff printing out right now. Took a little longer to make some mods than i expected.

airtruksrus
1st April 2014, 12:47 PM
Just the looks of it should be a great improvement for stiffening up the weak points. This will definitely provide a good test bed for strengths and weaknesses. With my small cam facing aft again, it shows any flexing during the flight along with key areas. Hope it works out.

tushev
18th June 2014, 10:49 AM
Dear Hobby UAV,
Can you mold the Techpod using the same molds in EPP foam or higher density EPO foam?

Hobby UAV
18th June 2014, 01:28 PM
tushev,
right now the answer is no. Not at least until I do another run. It will probably be another year until this run is sold out.

kalikraven
18th June 2014, 01:37 PM
EPP is cut from blocks not molded.

tushev
18th June 2014, 03:19 PM
Yep, I can imagine how expensive is to make another run even more in different material. Akording to Ming from Windrider EPP is much harder to work with. It needs more pressure in order to be evenly distributed around the interior of the mold.

tushev
18th June 2014, 03:31 PM
Sure EPP can be molded. Our dear host Sentry has one of those Scout Bee EPP wings which are molded.

DroneResearch
22nd June 2014, 01:04 PM
Hello Wayne at Hobby Uav...

Hobby UAV
22nd June 2014, 02:16 PM
Hey droneresearch, this thread is about some of the modifications I have been working on I did some test flying and I am happy with the results.

Hobby UAV
22nd June 2014, 02:18 PM
http://youtu.be/uvNo45y4h9U

DroneResearch
22nd June 2014, 03:12 PM
Keep up the good work...

Hobby UAV
24th June 2014, 01:49 PM
I finally found a good use for leo's acting skills.
https://hobbyuav.files.wordpress.com/2014/06/20140624_092256.jpg?w=600
Looking for 5 beta testers.
https://hobbyuav.files.wordpress.com/2014/06/20140624_102750.jpg?w=600
https://hobbyuav.files.wordpress.com/2014/06/20140624_092316.jpg?w=337
https://hobbyuav.files.wordpress.com/2014/06/20140624_102830.jpg?w=600.
$20 for the upgrade kit for the first 5 beta testers. If you are interested just send me a PM.

Hobby UAV
25th June 2014, 02:52 PM
Here are a couple spars I made yesterday. After a quick sand this morning they are looking pretty sweet.
https://hobbyuav.files.wordpress.com/2014/06/wpid-20140627_104146.jpg?w=600

Hobby UAV
30th June 2014, 02:59 PM
so I had some problems with my tooling. the rod I was using started to become jammed in the wrapped tube after things have cured.
https://hobbyuav.files.wordpress.com/2014/06/wpid-20140630_113115.jpg?w=600
the top one blew up when i was trying to press it out and the bottom one is a jig I made with 1/4 20 all-thread to press it off, but it became jammed and broke the all-thread.

I have some precision ground 9mm rod and some different mold release on the way. I did manage to make the perfect shaft and modified the new wing plates and pins.
https://hobbyuav.files.wordpress.com/2014/06/wpid-20140630_113309.jpg?w=337
The new tooling and mold release should be here in a few days.

Blizzard1287
30th July 2014, 02:06 AM
Hi Wayne, When building the Techpod upgrade it didn't quite suite my needs so I hope you done mine but I made a slight mod that hopefully others can benefit from. As everyone on here knows, separating components is key to long range, but the upgrade kit is good for servos only (at least on the wings). So I created a simple box that you can use to connect what ever you want on your wings. I plan on using a Vtx on one wing with a UHF Rx on the other. This simple box allows easy connection between each component using a standard set of servo extenders. If this gains popularity I'll add an instruction manual later on, but for those who are interested you can download the STL files here (http://www.thingiverse.com/thing:411410)

http://thingiverse-production.s3.amazonaws.com/renders/10/8c/af/b0/2c/DSC_9046_preview_featured.jpg

http://thingiverse-production.s3.amazonaws.com/renders/8c/8f/d2/c3/80/DSC_9051_preview_featured.jpg

http://thingiverse-production.s3.amazonaws.com/renders/39/72/12/4b/3b/DSC_9048_preview_featured.jpg

Scotttu
26th August 2014, 12:49 PM
Sweet, will be spending time in this thread.

I am building another TechPod! Still have faith that it will have no issue doing the 10 mile flight.

Hobby UAV
26th August 2014, 12:58 PM
Hey Blizzard, nice mod.Are you still going to install the 7 mm rod like this?
http://hobbyuav.files.wordpress.com/2014/07/20140715_184939.jpg

Scotttu
30th August 2014, 10:20 PM
OK So the wing gets cut at the flapline on each one and affixed inside the clamp, glued etc etc???


I got the kit and I'm sure I can figure it out but a bit of help would be advised.


Wayne, there were only two connectors, were there supposed to be electrical female connectors?


Thanks, got all parts, ready to built......

Hobby UAV
30th August 2014, 10:25 PM
There should be two sets of connectors. I think i put them together when I packed them.

Scotttu
6th September 2014, 12:33 PM
OK I am concerned about the point where the wing joins to the inner wing that is permanently attached to the fuze.


In doing a LIGHT test of the strength I heard popping and developed a crack (which is now on the outside of the wing and repaired).
I picked up a 1/4" aluminumrod to run between those so hopefully it will correct it.


Cannot stress enough that a 2nd spar should be used with the upgrade kit (the smaller holes) - I did not do this but I may go back and retro fit it.....
I don't plan on putting any stress on this bird this time but a wind gust or something may put some stress on.....


Think this may be a viable solution to distribute the stress.


http://www.tngbbs.com/photo/rc/TechPod/Build2/rod1.jpg
http://www.tngbbs.com/photo/rc/TechPod/Build2/rod2.jpg

Hobby UAV
6th September 2014, 12:35 PM
There is a second spar. It goes through the hole in the rear part of the new plates.

Hobby UAV
6th September 2014, 12:42 PM
It doesn't look like you have installed the 7mm rod here yet.
http://hobbyuav.files.wordpress.com/2014/09/20140715_184939.jpg

Scotttu
6th September 2014, 01:08 PM
I have not, so those are the 6" long spars? I have 3 of those including the original that came with the kit.


There is not much of a receptacle for it to go into though, it will just be on foam when you slide the wing in?