|dave parnham||23/05/2015 19:48:04|
190 forum posts
Has anybody ever fitted electric retracts to the foam wings of a trad. kit Acrowot.
im currently madly in love with mess.BF109e and suddenly realised that I can re-cover and paint my beloved Acrowot to look very similar, enough to satisfy me anyway.
And I currently have some cheap HK electric retracts.
Any pointers? separate batteries....... or just plug into rx in ch5 and go?
|Concorde Speedbird||23/05/2015 20:34:02|
2735 forum posts
To be honest I just wouldn't! It will make it heavier and the wing would be weaker. If you want a 109 I would recommend a Funfighter kit. Small and practical and they look great! They are made by Cambrian and Cambria and they are great.
413 forum posts
Oddly we were talking about that at the field today. Some how we all turned up with at least 1 Chris Foss model each. One of chaps knocked the under carriage off his Acro after a dead stick low and inverted left him short on options. The Acro looked a lot better sans wheels and someone said they had seen an old kit acro fitted with retracts and it looked good and flew well. I have no details on how it was done. As CS says you would need to think carefully about the wing structure.
|dave parnham||23/05/2015 21:00:24|
190 forum posts
well im seriously thinking about stripping the covering off and having a look at what can be done.
Problem no1 my HK electric retracts are 80 degrees coz I got them for the BT plan bf109 but they are too short in the leg and only 2.75" wheels.
So problem 2 means mounting them retract units in the middle .....wheels pointing to wingtips, but then the Aileron servos need to be moved....not a big job I know but hey ho.
|dave parnham||23/05/2015 21:17:33|
190 forum posts
**LINK** the only clip I could find
|974 forum posts|
Now that Is nice...........
512 forum posts
Please do a modblog, string, thread, thing, if you go ahead!!!
1145 forum posts
That's how all Acrowots should be.
.........apart from that big smelly, dirty, noisy lump hanging out underneath!
|Tony Manzur||03/12/2015 22:42:17|
20 forum posts
It can be done. This is my glassed mk1 Acrowot. Weight is 4.75kgs and u/c mounts have carbon reinforced spar between them to spread the load and strengthen the wing. Saito 125 overcomes the weight so she has unlimited vertical performance. I should have added flaps though... She does need a loooong runway for landing.
|Tony Manzur||03/12/2015 22:45:05|
20 forum posts
Ah, I see someone has already linked it...
Edited By Tony Manzur on 03/12/2015 22:45:41
|Dave Smith 15||03/12/2015 22:56:07|
|28 forum posts|
I put a set of air retracts into an Acrowot about 25 years ago, from memory I used a couple of full depth ply spars to anchor the gear onto. Didn't take any pics and can't remember how it flew, back then I was building, flying, then selling Acrowots at a fair old rate!
9334 forum posts
Seperate battery for the retracts, for safety sake, just in case one binds up and keeps working thus draining the Rx battery
|Jon - Laser Engines||04/12/2015 08:25:49|
|5621 forum posts|
Wonderful job on that P51 style conversion. I also really like the wing fillets and blended fin as well as the shiniest paint job i have seen in a long time!
Anyway with a foam wing i would not be traumatised by it and would expect it to work well. As a few others have said use a 2nd battery for sure to prevent rx battery depletion. I have been saved by this once before on my ripmax harmony. I did get my gear back down but it took a while. The battery was dead enough for the rx to hae thrown in the towel thats for sure
Conversions like this are great as they add something different to standard plane. Currently i am converting my long suffering Pulse125 into a twin and fitting retracts. It wont win any beauty contests but it should fly nicely
1939 forum posts
Thing of beauty, I could watch those wheels go up and down all day. Is that a spray job or film cover ?
|Bob Cotsford||04/12/2015 11:00:26|
8748 forum posts
With modern electric retracts using current overload shutoff I've used a single battery on a couple of models, though with bigger models or mechanical retracts I still use a separate retract battery. I recently tested some HK all metal 7.5Kg size units and the stall current was around 1.8A which went to zero after around 3 seconds, so bear this in mind when sizing your battery. An A123 2.3AHr dropped 0.04 volt with the retract stalled.
As for an Acrowot at over 4Kg - rather you than me but it does look superb.
|Jon Laughton||04/12/2015 12:44:52|
1226 forum posts
Tony - as many have implied already you are to be congratulated on a superb Acrowot! It would be good to hear how she flies at that weight....are landings a little 'hairy' and how have the stall characteristics changed (if at all?)
Details of your conversion would be much appreciated....Jon
|Hangar 9 nut||04/12/2015 20:37:57|
243 forum posts
I have just refurbished an Acro Wot with flaps as of yet not flown !
|Tony Manzur||08/12/2015 02:13:14|
20 forum posts
Yes, it's a spray job. Cellulose with a gloss aerokote finish. Not great adhesion and I should have invested in epoxy paint.
With the saito 125, take offs are easy: the power just launches her forward and up without issue, but yes, landings without flaps on a very small runway are hairy to say the least.
Stalls are as good as a normal Acrowot, but they just happen at higher speeds. I once over flared at lowiah speed and she looked like she was going to tip stall, but control remained good a a bit of rudder and aileron caught the rotation and managed to flop her down.
Originally, she was built with fixed gear and I had a full seasons flying with her. @ 4.25kg with a saito 91, she was fast, stable and great for old school aerobatics. As usual, I got a bit complacent and put her in a deep stall/spin pulling through a loop too vigorously. I'd like to say that the rudder split through heavy use and put her in an heavy spin, but it was probably me. She went in very fast with zero pitch and bellied in with a 30degree trajectory. Enough to re-kit most planes, but she remained largely intact.
The u/c folded into the wing with the edge of the glass u/c cutting 2 gashes in the lower surface. So after a few years gracing my attic, I just thought that a simple repair was dull, so in cutting out the damaged area, I decided to drop in wheel wells with a carbon spar front and rear to spread the load. Hangar 9 bluenose retract units (cheap eBay buy) were very impractical... Weight and size... But I managed to squeeze them in somehow. Since this was my very first retract build, I had to complicate matters with main doors...
And yes, a separate power source for the u/c system. All works on an assan gear door sequencer, life batts with a regulator for the u/c.
A new canopy and stupid amounts of rubbing down and here she is.
Ive had another moment since with a loose batt connection one day giving me intermittent control. She 'landed' some 500 yards away in tall grass. In the best tradition of dumb decisions, I tried to retract the gear thinking it might be better to flop into the long grass, but too late so she went in with gear half up and doors open.
Unbelievably, she survived with twisted and slightly bent gear and the doors slightly over-opened. The way she flipped over, the gear must have taken a huge knock, but no signs of damage to the retract units, mounts or structure.
I straitened the gear and have flown her since, but on the next flight, the looseness of the oleos caused the wheels to toe-in and she flipped over breaking the rudder... Again. So rudder no3 has been fabricated, new oleos acquired and the last few coats of paint applied to the rudder before fitting, so she should be ready for next season.
With the wheels up on a 14/11 prop, she is fast, and sounds ballistic. Gorgeous actually.
Really have to get some vid of her next time. Well worth the effort.
Edited By Tony Manzur on 08/12/2015 02:18:17
|Tony Manzur||08/12/2015 22:05:46|
20 forum posts
The Acrowot in its first form
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