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Old Dec 02, 2012, 09:59 PM
A geriatric flier
Watdazit's Avatar
Australia, NSW, Braidwood
Joined Nov 2008
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Quote:
Originally Posted by David Hipperson View Post
Well, you do beat me Watdazit as I'm a couple of years younger than you..........
When I was your age..yada yada yada.

You should be able to punch through anything with 65C. When you have a moments can you weigh your battery please. I have not got my skills down to virtually hovering coming in to land. Are you using flaperons?
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Old Dec 02, 2012, 11:27 PM
Faster is Better
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United States, AZ, Gilbert
Joined Jul 2012
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Originally Posted by Watdazit View Post
Oldeman's information about the Dynamic motor and prop is interesting and I would like to see what Watts and Amps it is drawing.
I measured when new... still had the stock 12x6.5 prop: Roughly 24 amps WOT static... with a fresh battery... so 300 watts? I soon broke that prop and replaced it with a 12x6 carbon. I haven't measured the newer setup.

Quote:
Originally Posted by Watdazit View Post
I have come from helis and there is not so much fiddling required with motors, batteries and blades as there is with planks so I am not sure whether what you say Oldeman is right but this is because I do not understand it and not because I think you are wrong.
I can understand that.

I am thankful to have a wonderfully well behaved D-S... and if there is something I can measure or test for you guys who are experiencing control issues... something you'd like to compare to your own planes... let me know. We have early sunsets here (AZ does not observe DST)... so I generally can't fly on week nights. But requests for bench testing/measurements any time, and test flights on weekends are welcome.

--

By the way, I know from reading scattered comments... in this thread and elsewhere... that I'm flying much bigger batteries than "normal". I'm fitting 2450 mah in there. It's snug... and I had to cut the foam "stop" out so I could slide them back under the wing... but I love the flight times I get. I set up a throttle timer to count down when my throttle is above 15%... set for 10 minutes. When I land, I have about 25% remaining. That's 10 minutes of throttle-on time... wall clock time is amazing if I decide to just climb and soar.
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Old Dec 03, 2012, 12:44 AM
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Kilsyth, Victoria, Australia
Joined Oct 2003
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The 3S 1300 65C packs weighs in at 118g.

As for hovering I did meant that this is during a stiff breeze and no as previously mentioned I do have the Blaze set up for spoilerons not flaperons but I don't bother to use this. Although I have DX6i and DX7S radios my Blaze has a Fly Dream receiver and the Tx is a Futaba 6
EXA converted to the Fly Dream module.
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Old Dec 03, 2012, 06:54 PM
A geriatric flier
Watdazit's Avatar
Australia, NSW, Braidwood
Joined Nov 2008
772 Posts
Thanks David and Oldeman for the info. When I can around to it I will do a test on the watt/amp meter with my Blaze.

The weight of the Airstrike 65C at 118g is good. My 1300 30C Dualskys weigh 112g and some 1500 20 -30C Turnigy weigh in at 132. The ST Models 15C battery which came with the Blaze weighs 106g.
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Old Dec 03, 2012, 07:44 PM
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United States, NC, Richlands
Joined Jun 2011
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FWIW, here's some numbers from my archives:
(Have no idea how the tabbing's gonna reproduce here but, copy-n-pasted):
BATTERY WEIGHTS: mAh Wgt(g) mAh/g
TNT 3s 1000 15~25C 1000 79 12.658
TNT 3s 1300 25~50C 1300 111 11.712
Gens Ace 3s 1300 25~50C 1300 124 10.484
Tgy 3s 1800 20~30C [#1] 1800 157 11.465
TNT 3s 1800 25~50C 1800 147 12.245
EZ Flite 3s 2200 30~60C 2200 172 12.791
TNT 3s 2200 25~50C #1 2200 184 11.957
Tgy 3s 2200 20~30C #1 2200 191 11.518
Tgy 3s 2200 30~40C #1 2200 195 11.282
Gens Ace 3s 2200 25~50C 2200 194 11.340
Tgy 'Blu' 3s 2200 35~45C 2200 201 10.945
Gens Ace 3s 2500 25~50C 2500 236 10.593

*TNT = Turnigy Nano Tech
GA = Gens Ace
Tgy = Turnigy 'Blue Plain'
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Old Dec 03, 2012, 11:26 PM
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Kilsyth, Victoria, Australia
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Using the Aeronaut prop my Blaze does 196watts in. From memory the stock prop was roughly 15watts less. If I were trying to equate this with other foamies "power" or "glider" it is by no means powerful if those models being considered are like the Funjet, Dogfighter or Blizzard but as that power escalates you can run into problems regardless of what you may read in some threads.

The Blizzard for example needs a fair amount of modifcation if pushed much beyond basic. Strengthening plus taping to stiffen the wings to help eliminate flutter etc. Even run stock one has to add in all of the stiffening cross glued rods before any taping.

If I were considering going to up the power on the Blaze I'd suggest that something around 250 watts might be close to the limits. By all means prove me wrong. Once we get over 250 watts per pound the whole airframe might well need a rethink. For me, even though a tinkerer, if I wanted a genuine warmliner I'd want a mainly glassed model and the effort in trying to do that to the Blaze feels a little counterproductive.

Lots of wreckage has convinced me that rarely do radical changes bring improvement.
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Old Dec 04, 2012, 12:28 AM
A geriatric flier
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Australia, NSW, Braidwood
Joined Nov 2008
772 Posts
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Originally Posted by David Hipperson View Post
................Lots of wreckage has convinced me that rarely do radical changes bring improvement.
I agree. I have not carried out any increased power changes on any of my planes or helis. I might use what I would consider better quality equipment than standard but this still keeps the models within their design concepts. With planes I think, if you want something faster or more aggressive then the best thing is to buy that type of plane.
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Old Dec 04, 2012, 05:06 AM
Earthbound Skyhound
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United States, NC, Richlands
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On the other hand, many 'upgrades' to the power system by owners stem not so much from a desire to make rockets out of rowboats as it does to make better craft from many mfrs' habitual use of components barely able to make minimal sustained flight without stressing said componentry.

Good case in point - my Minimoa. The motor supplied - and the ESC for it, were designed to be powered by (I don't recall exactly at the moment) something like an 8.7 volt battery. Where the hell do you find something like that? Some weird combination of battery cells that aren't even used today. But it's supposedly OK to power this with either a 2s or 3s LiPo. But even with the 3s it'll barely get out of its own way....plus, run it for about a minute solid & you can plan on replacing the melted plastic motor mount. Does anyone smell a batch of old motors lying around in a warehouse somewhere that someone decided they'd like to sell?
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Old Dec 04, 2012, 08:29 PM
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Update: My first attempt at painting did not go well. I decided on a red and black contrasting color scheme and since I had heard that spray paint will eat EPO I decided to try just regular old acrylic paint. Well the acrylic worked well on the nose cone and plastic parts but was useless on the foam itself. even with sanding beforehand it wouldn't stick at all except for the bit of epoxy residue from repairs. It coats fine although I don't have an airbrush so I didn't get an even tone, but after painting the whole fuse I found out that even super low tack pinstriping masking tape would take the paint right off cleanly. In fact I used packing tape to take the rest of the paint back off the fuselage.

Seems like at the very least I'm going to have to use a spray primer with a little bite, but find one that won't craze the foam either.. ugh...

suggestions? comments?
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Old Dec 04, 2012, 11:57 PM
Earthbound Skyhound
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United States, NC, Richlands
Joined Jun 2011
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The only one I've sprayed, I used Krylon. It's an old beater anyway so didn't much care for a fine finish but, paint's still holding.
Some foams have an almost shell-like 'oily skin' that even sanding doesn't assure of a grip. You might try scouring with isopropyl alcohol* as a prelim, see if that'd clean enough of the oily 'feel' away to let the Krylon get a foothold.

*In case you don't know - not regular 74% 'Rubbing' alcohol, which has & leaves behind skin-protecting oils, itself. The one you want is like 96% (read label) & usu. comes in the brown plastic bottles. Check Wally World's medical dept.
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Old Dec 05, 2012, 12:12 AM
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Dear John,
You are running into the usual problems with painting foam. The first thing you have to realise is that most of the foamies we purchase still have some sort of release agent still present from the mould process. Although this can be cleaned off some will seep out simply because the outer surface has virtually trapped some within the process. This means that almost all paints are likely to come off. The only question is how soon.

Certainly Multiplex Elapor will accept most paints and I choose to wipe over first with Shellite. Because other EPOs do vary I am not recommending this for all EPO. If you can find a suitable cleaner fine but even warm water with detergent can work.

Surprisingly I find the best (and cheapest) option is artists acrylic. Huge choice of colours and if used with good quality brushes will go on very easily and is water soluble. I don't mask but draw up the markings is soft pencil and then carefully hand paint up to that mark line. With some care straight lines are quite achievable.

Superficially the problem is that the acrylics dry fast but dry matt. For a better and slightly more robust finish artist suppliers also sell tubes or bottles of clear finishing acrylic lacquer. Allow the colours to dry for at least a full day prior to brushing on the clear or some smearing may occur. The useful thing is that the clear can usually be obtained in gloss, semi-gloss or matt which gives a few options.

If you stay with stock colours and a little goes a long way the even any minor damage or wear can be recoated without effort.
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Old Dec 05, 2012, 01:56 PM
Faster is Better
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United States, AZ, Gilbert
Joined Jul 2012
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Quote:
Originally Posted by David Hipperson View Post
...snip...
If I were considering going to up the power on the Blaze I'd suggest that something around 250 watts might be close to the limits. By all means prove me wrong. Once we get over 250 watts per pound the whole airframe might well need a rethink.
...snip...
(I know this discussion was a few days back... but I just saw it. Sorry.)

I believe that's a true statement if you are discussing a power increase due to prop "pitch"... which implies an increase in full-power flight velocity. There are a lot of comments in here about loss of control surface authority due to excessive speed... for which an airframe rethink might be a good idea.

However, I'm getting close to 300 watts on my Dynamic-S... and have no control authority issues... because the power is spent in air "volume" instead of "velocity" (i.e. prop diameter instead of pitch). With a 12x6 prop... it has amazing pull/climb without excessive speed. This also means that idling the prop (i.e. applying *just* enough throttle to spin it) makes a more effective air brake.

I, for one, love this alternative approach to increasing power. Just thought I'd mention it for the benefit of others who might be trying to decide on a prop/performance change.
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Old Dec 06, 2012, 01:39 AM
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United States, ND, Fargo
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What I decided to do after reading a few threads was to sand the foam well with 400 grit, use denatured alcohol to remove the dust and any remaining release agent, and use minwax water based polycrylic as a base coat for spray. the recommended number of coats seems to be at least 3 so I'll do like 5 with wet sanding in between as the polycrylic weight is next to nothing when it dries. with the polycrylic acting as somewhat of a shell, the spray paint should never even touch the foam. people seem to have had good results with this method but time will tell. it will take me another day or two to get everything with a good 5 coats.
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Old Dec 06, 2012, 01:40 AM
A geriatric flier
Watdazit's Avatar
Australia, NSW, Braidwood
Joined Nov 2008
772 Posts
Quote:
Originally Posted by David Hipperson View Post
The 3S 1300 65C packs weighs in at 118g.

As for hovering I did meant that this is during a stiff breeze and no as previously mentioned I do have the Blaze set up for spoilerons not flaperons but I don't bother to use this. Although I have DX6i and DX7S radios my Blaze has a Fly Dream receiver and the Tx is a Futaba 6
EXA converted to the Fly Dream module.
Hi David
Can I ask you please what rates you set up for spoilerons when you did use them. Just to give me a starting point. I have been practicing taking off and landing today. Take offs are fine, landings are 50%. My landing strip is only 30 m long and there is long grass either side. I need to be on about the right speed when I hit the edge of the clearing or I have to power up and go around again. I have never used spoilerons before and I assume some rudder control is required.

The weight added to port wing has almost corrected the turn to starboard. I have been able to reduce my trim to 5 beeps.
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Old Dec 06, 2012, 06:42 AM
Earthbound Skyhound
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United States, NC, Richlands
Joined Jun 2011
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Quote:
Originally Posted by johnwohl View Post
What I decided to do after reading a few threads was to sand the foam well with 400 grit, use denatured alcohol to remove the dust and any remaining release agent, and use minwax water based polycrylic as a base coat for spray. the recommended number of coats seems to be at least 3 so I'll do like 5 with wet sanding in between as the polycrylic weight is next to nothing when it dries. with the polycrylic acting as somewhat of a shell, the spray paint should never even touch the foam. people seem to have had good results with this method but time will tell. it will take me another day or two to get everything with a good 5 coats.
Polycrylic? Ummm....I'd strongly suggest you try it on some scrap material first - even if not foam -- more for how well it accepts sanding or any further 'disturbance' after drying. I had far less than desirable results when I tried it for 'planking' my Blaze's control surfaces. It's like laying down layers of soft vinyl rubbery film, & when you rub it later (as in sanding before the next coat) it 'pills' & the particles 'snowball' as you continue rubbing, peeling much of it away.

If I had it to do again, it'd be water-base polyurethane - absolutely!
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