arcticflyer

finster - That center section is laminated balsa (on its side) really strong but light...I'm gonna glass the floor of the battery area and run an extra piece of glass down the center on the bottom before applying the top .75oz layer. I am amazed at how ridged this mod makes the center of the airframe. It would make a great camera platform

Mountain bike fenders.......now that's an idea

Arcteryxxx

Picked up a couple of fenders today for my ongoing project. The shape is nearly perfect and the material is promising. Just some clever cutting and a heat gun job and I think it will be just right

Wheelnut

My Feedback: (81)

Make sure you're wearing a dust mask.

beachbrada

My Feedback: (17)

With the 16/25/2ce do u guys think I should glass the body or will I be fine with adding just carbon fiber support throughout the body and beefing up the elevons, hinges, and switching to metal gear servos? If I should need to glass the body can someone lead me in the right direction on how to go about doing it. Thanks

Arcteryxxx

You should glass the body - that's my advice. I was reluctant to glassing it too, but it's really not difficult at all. I will be glassing everyting from now on! My DuraFly 1.4m Spit is next.
I believe Murdo described the technique to use some pages ago... Look up posts ## 108 and 185.

Btw: I use boat building (laminating) epoxy with a 2:1 resin and hardener mix. It's the easiest to work with (thin), it's totally colorless (not like the amber color of Z-poxy finishing resin and others), it is very strong but it takes much longer for it to cure. It's also way cheaper than the stuff from your LHS.

Here's a pic of Sleipner after the maiden glassing...
static.rcgroups.net/forums/attachments/3/0/2/4/3/7/a3504345-113-IMG_1560.jpg

murdnunoc

For those interested in 6S data on the Mega 16/40/2CE, I got some from the first three flights of my buddy's plane.

APC Sport 7x5
76.2A and 29,853 RPM.
Pitch speed of 141mph

APC Sport 7x6
89.3A and 28,679 RPM
Pitch speed 163mph.

APC Sport 7x7
100.5A and 27,442 RPM
Pitch speed 182mph.
Actual Airspeed 162mph

I took the readings at three seconds into the second pass of each flight, and the battery was 23-27% discharged for each of the data points.

The flights consisted of four full throttle passes of around six seconds. When it landed immediately after the last pass, the motor windings were 110F on the 7x7 prop. Outside air temp was 85F.

This motor can be a real speedster on 6S and 7" props with great throttle control. If the left stick is slammed up for most of the flight, stick with the lower pitch props. But for drag racing with cooling between passes, the 7x7 and even 7x8 should be good candidates for awesome speeds when the airframe is super sturdy and super slick.

arcticflyer

Murd- Those are some pretty impressive numbers[sm=spinnyeyes.gif]...what are you using to measure your airspeed?

WideBodyS - Got the floor of the FUZ glassed and the trailing edges on today...thought of an easy way to mount the motor last night will send pics when I finish making the mount (that center rib solved the problem). Still debating the top cover pieces or piece.

What are you guys using for filler or what could I use for filler to fix some gouges in the airframe before glassing? This FUZ came in pretty rough shape[]. I got some of the gouges out with boiling water.

Rain and snow for the next five days[:@]....guess I'll be building!

murdnunoc

I measure airspeed with video and Doppler. The airspeed has to be inferred by averaging the fastest upwind pass and fastest downwind pass, but that's how the FAI does it!
I have an airspeed sensor for my Eagletree logger, but have had issues with it not even coming close on speed. I'll have to revisit the sensor mounting, but it's not too high on the priority list right now.

For most filler jobs, lightweight spackle works fine. Sands very easily. If it's a deep repair or build-up, it's best to fill in the majority of the area with a piece of foam, then use filler for the final shape.

For a little better performance at the expense of a lot more trouble, you can use fiberglassing epoxy with microballoons mixed in. The microballoons weigh nothing, but thicken up the epoxy to a peanut butter consistency and make it very easy to sand.
The microballoons/epoxy filler has a much higher impact resistance than spackle does. It also forms a stronger bond to the foam.
But you have to take GREAT care sanding it! The dust is a million little cut glass particles that are like razor blades to lungs and eyes. So wet sand it or use appropriate face/skin covering to keep the dust away.

I go for the extra trouble of microballoons for a build I really care about. But the spackle is 90% as good in my eyes.

arcticflyer

Was thinking micro balloons and just happened to have some....so, will have to dig up a mask. [:'(]

Have a Wingshadow airspeed device and to be frank I feel the same way about it[sm=72_72.gif]
What about the EagleTree GPS doesn't that give a top speed or I think it would be (top Ground Speed).

murdnunoc

I do really like the idea of GPS for speed measurement. I just don't know the sampling frequency on it. You're right that it still only gets groundspeed, so upwind and downwind would still have to be averaged. That would need it would have to be used with the logger that records speed for the whole flight.
But if it's accurate, it would be great! There would not be the parallax error inherent to Doppler and radar, where speed measurement is reduced because it's not directly in line with the gun/camera.

The pitot/static airspeed sensor is still the most accurate tool. In concept. The mounting issues and calibration make it not quite as good in real world use, though.

Anyone tried the GPS to see if it's a good tool?

Wheelnut

My Feedback: (81)

We mostly used GPS for speed on our Fast Electric Boats, The fastest I ever got was 45mph

murdnunoc

Hmm...
If it's accurate enough for boats, with their relatively short courses compared to our flying area, maybe the GPS would be a good solution! Do they use it for competition purposes?

Wheelnut

My Feedback: (81)

It should be very good fly flying. You can get a much longer run for the speed test.
It is used for competition purposes but not "Officially"
For races they use transponders.

Arcteryxxx

I'm trying out a canopy made from a mountain bike fender. Think it will turn out fine after shaping it a bit with the heat gun.
Here's a pic from the test fitting:

arcticflyer

I might be takin a trip to the bike shop

arcticflyer

The WideBodyS is coming along fine....micro balloons are on and tomorrow will final sand to get ready for exterior glassing.

One method I have used and will use again is glassing with WBPU (water based polyurethane) called Polycrylic. This method sticks the .75oz glass to exterior very well...not as well as the epoxy finishes...but, it is much cheaper, easier to clean up, and doesn't stink up the house. I put a thin coat down, lay down the glass, then 2 coats on top with lots of dry time between coats.

ARC- not sure if those fenders are wide enough for my application....that pic shows a 2650 20C 6S battery laying inside with plenty of room 4000mah should fit with no problem

moparmyway

Lets see how durable you find the Polycrylic to be after a dozen or so flights. [sm=confused.gif]

Arcteryxxx

My suggestion is that you try to find A fender - not necessarily THIS fender.

Here's the one I got: http://www.biltema.no/no/Fritid/Sykl.../Skjermer-MTB/

Maybe something like this should be fitting yours better http://www.biltema.no/no/Fritid/Sykl...Bakskjerm-MTB/

murdnunoc

Arcticflyer,
I'll have to put in a second vote for using epoxy rather than WBPU for glassing. The WBPU does go on nice, and its properties make it easy to work with, but in my experience, that's where it stops. You already said that you'd seen it to not be as strong as epoxy, so on a build that you're putting so much work into, isn't it worth it to go with the best product?

When done right, fiberglassing epoxy goes on just as easily as the Polycrilic. Just use alcohol to clean up instead of water.
When spreading the epoxy, I've found that a credit/gift card works better than a brush for wetting out the glass. Just start with a big puddle and push the epoxy ahead of the card at a 45 degree angle. This presses the glass down and smooths it, while getting just the right amount of epoxy into the glass.

arcticflyer

Hate to admit it guys...but I've done all 3 of mine with WBPU. I've been flyin my second heavy for nearly a year now (it is the black and white one in pics a couple of pages back still on first paint job, lost count of the flights). Where the WBPU appears to be weaker is when you decide to change a stripe, servos, or a burried receiver. Most of the time the trim strips come off with no problem but on occasion it will pull the covering up in small spots where the epoxy probably wouldn't. I just inject a little glue (at the pull up) and stick the trim strips back down. I wish the current plane was epoxy because I am constantly changing components which leads to little minor repairs.
My problem is, I'm in a rented (small) place right now with no proper (shop). I work in a small bedroom soooooooo.....the good stuff will have to wait.

ARC- I like the shape of that second fender...I've got two bike shops in town I might check them out tomorrow. May still end up fabricating something out of fiberglass.

Arcteryxxx

Happy searching my friend! Just a thought: are you familiar with scoop ball? Might just be another option: http://furlongspetsupply.com/images/...?productId=153

pencon

Hi Folks , here's some pics of my Strykorski .Had some .025 aluminum lying around so I tin- bashed an Aluminum nose section louvered back hatch and a psuedo mock turbine nacelle .These 3 pieces weigh next to nothing and add a lot of strength . 1/4 inch carbon tubes in place of the stock carbon rods as well as installing a flat carbon trailing edge anchored into the wing with 4 inch pieces of the same material . (dremelled slots etc ) Fiber Aileron hinges into hard balsa ailerons .With a new Het 2w-20 It fluttered a Vertical stab off ,so custom balsa Stabs covered in fiberglass and cut down an inch in height as well as different shapeare on it npw. For good measure the whole bottom of the plane is fiberglassed with one oz cloth and zpoxy .Next mod - 160 ice lite hv and 4s 2600 mh 45c lipo. I'm pretty new at this whole electric thing and this is my first Stryker .With 2600 mh my flights will be quite short but I didn't want to add a ton more weight with a 5000 mh brick ..

moparmyway

Nice pictures.
Why the HV 160 Lite ??
ICE 200 Lite (same physical size) runs 6 cells at better amperage capacity all at the exact same price as the one you are looking at.

When the ICE 150 comes out, that will be the ULTIMATE ESC for most Strykers !!

pencon

"Why the HV 160 Lite ??
ICE 200 Lite (same physical size) runs 6 cells at better amperage capacity all at the exact same price as the one you are looking " Well I guess it's because I didn't know that . It's a little late to return it now , I already have it and it was a custom order from my LHS .I don't plan on running 6s anyway .The 160 is suppposed to be able to run 12s (so the ad says)

pencon

Moparmywy , Is the new 150 any smaller and lighter than this huge 160?