F-86 pocket rocket

[akent]

Do you think it stalled on you?

Mine stalls if you just look at it wrong.

I still haven't fixed mine from the fender bender. The plywood plate is definitely a weak point when you have a battery on there!

I am interested in how you work the crinkles with a hair dryer. My 20+ yo heat gun is a very hot gun that I use for heat shrink and monokote and the like.
My wife's hair dryer doesn't get hot enough to do anything other than dry her hair.

Any works of wisdom for reforming crinkled foam? Heat ranges, etc.?
Kent

[19000rpm]

I'd been doing some low altitude aerobataics. It went into a nose in spin, so maybe I had the ailerons over a bit too much.

It is easy to stall though. I have the slightest bit of down elevator trim in it after a little up for launch. That helps to keep the nose from going up when you get slow.

You don't need excessive heat. A blow dryer is plenty. The first time I tried it; I over did it and got the foam to balloon up. A slow approach is better. Just apply heat for a few seconds and take the heat off even if the wrinkles aren't all gone. If you keep the heat on too long all of a sudden you've got balooned cells. Let it cool a bit then repeat. Gradually the foam will fill out. It will have a little cell expansion but it shouldn't look too bad.

[19000rpm]

After my little accident posted above I repaired the plywood equipment board and flew it a few times. This morning I was bringing it in for a nice landing on the grass and a tank hooked stopping it rather abruptly. The tank was fine, but the weight of the battery broke the ply and foam support sending the battery out the nose.

So I decided to do this: 3 small CF tubes under the plywood front, middle and center.



If this doesn't do it I'll order a new fuse, only 32 bucks, and add the CF before I fly and wreck the plywood.

[19000rpm]

Well, I finally did get around to flying it after the repairs. It's even slower to accelerate than it was before, because of the repair weight, but it does fly really nicely. It definitely benefits from a bit of a breeze at the nose when launching.

[Gabe]

Sometimes I prefer a heavier plane just for the stability against the wind. I sti give two thumbs up for the innovative repair.

[19000rpm]

The repairs are very stout. I could probably fly it into a brick wall now, but I'm going to try to avoid that. ;D

[19000rpm]

I was talking to Hobby Lobby the other day and after I explained what had happened, they are sending me a new airframe and motor at no cost. That was really decent of them. Something they didn't have to do.

[akent]

Jun 19, 2010 15:34:01 GMT -6 19000rpm said:

I was talking to Hobby Lobby the other day and after I explained what had happened, they are sending me a new airframe and motor at no cost. That was really decent of them. Something they didn't have to do.

That's amazing!

You lucky bastage!

[19000rpm]

Yep, they are good folks. Looking forward to getting it back in the air.

[19000rpm]

They went out of stock on the airframe and by the time they sent me the airframe the motor went out of stock, so I'm waiting on that. Anyway it'll be fun to get it flying again.

Kent, what do you recommend for an upgrade motor for that little fan?

[akent]

Humm, I really don't know about an upgrade for these.

I'm still flying mine stock. It is low on power, but it flies nicely. I have maybe 15 flights on mine now. I keep the speed up now, so I have had no more stalls. I try to fly scale, so all huge and smooth aerobatic maneuvers. That is challenging when you are used to throwing a hotrod around in the sky!

I do have a 64mm EDF unit that I bought from HC that feels like it has a lot more power.
Here's a link to it:
www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=6632&Product_Name=EDF64_with_ADH300_Motor_Assembled__252W%284300kv%29 It has a 4300kv motor!
I have a couple of these that I'm not using yet, so I may experiment at some point.
Kent

[19000rpm]

Thanks Kent. I think that may be just the ticket for an upgrade. Let me know how it works out.

[Gabe]

That's a darn cheap motor! I did a little research for you:

482 grams flying weight per website
New HK fan and motor produces 520 grams of thrust

Roughly just a hair over a 1:1 thrust ratio (1.08 to e exact). Not bad.

By comparison, the E-Flite Delta V 65mm system produces 408 grams of thrust on a 3S and 816 grams of thrust on a 4S. Given the extra weight of the 4S battery, I doubt the performance on a 4S would out perform the 3S. But that would require you placing the bird on a scale an checking the flying weights with both batteries.

So, in summary, your $20 motor from HK should out perform E-Flite's Delta V 65mm system - at least on a 3S battery. I'd call that a good find!

[19000rpm]

Thanks for the calcs Gabe. I'm going to order at least one.

BTW, the replacement motor is shipping from Hobby Lobby this week. It'll have to do until the HK unit gets installed.

I'm installing the CF tubing supports under the plywood equipment board similar to how I did the repairs on the first one. I'll also add tooth picks to the wing tank pylon mounts to strengthen those areas. All in all it will add a few grams, but it will be worth it for the added belly landing reliability.

[Gabe]

Sounds like a plan. Let us know when it's dialed in