SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old May 14, 2012, 06:26 AM
It should fly at least once
clive45's Avatar
Australia, NSW, Grenfell
Joined Mar 2006
2,607 Posts
Well if I was only 3Km away I would go and pick it up, think yourself lucky I have to drive 50Km round trip to pick up a parcel from the PO no matter what it costs to be sent. What they do deliver is only 3 times a week.
clive45 is offline Find More Posts by clive45
Reply With Quote
Sign up now
to remove ads between posts
Old May 14, 2012, 06:32 AM
Extreme CNC Alloy EDF
Extreme_RC's Avatar
Australia
Joined Mar 2006
11,756 Posts
Japan Post is heavily subsidised by the government, thats why its so cheap.
China EMS is strange, start of the year they are really tight with pricing and lots of issue with damaged shipments, once the reach their quota for the year they become more lax. EMS starts at 210RMB for the first 500g then 55RMB for each 500g additional weight, then usually less 30-40% depending on how big the senders account is. So average cost from China is RMB126 or AUD$20.00 for up to 500 grams then $5.25 per 500g on top.
Extreme_RC is offline Find More Posts by Extreme_RC
Reply With Quote
Old May 14, 2012, 09:24 AM
Registered User
United States, TX, Grand Prairie
Joined Nov 2005
5,861 Posts
Quote:
Originally Posted by Extreme_RC View Post
Lots of stuff in today, including the new CS10 spinners!

Fit is really nice, I pulled a random rotor from the box and grabbed a couple of spinners and they are a perfect interference fit. I think I will have to call them "Extreme Precision" Spinners

Also adapter blanks have come in, 4mm back in stock and more 3.17 and 5mm available.
Have you tested any heat transfer properties out of the spinner, seems like a great way to keep heat off the magnets of an inrrunner.

Also, do you have an ETC for your shroud...

Thx in advance for any input
erh7771 is online now Find More Posts by erh7771
RCG Plus Member
Reply With Quote
Old May 14, 2012, 12:28 PM
Registered User
genghiskt's Avatar
Joined Sep 2011
272 Posts
Quote:
Originally Posted by Extreme_RC View Post
Problem with shipping in Australia is the size, spinners wont fit through 20mm letterbox openings, not unless I squash them flat first

The other problem is if I activate the regular mail option, people will use it to order expensive items, and when the package is "lost" by Aust Post I am the one who gets the bad rep because I wont cover their non insured non registered article.

Cheapest option for spinners is $9.10 for regular mail in a bubble envelope up to 500g, that only just covers the packaging and label costs on top of the postage. Adapters go via letter rates everywhere.
Mark,

Can look into the shipping cost, I find it cost too much for me even I m in Singapore.
The air parcel cost from your site, I can ship a kilo of lipo from China by UPS.
genghiskt is online now Find More Posts by genghiskt
Reply With Quote
Old May 14, 2012, 03:49 PM
Registered User
Vienna, Austria
Joined Apr 2007
2,134 Posts
Quote:
Originally Posted by anlucas View Post
The ducting is quite good on this airframe.
I also tried with a slightly larger than 80%fsa on the thrust tube to see any differences in speed. Thrust was the same between 55mm and 62mm. Obviously 55mm gives a higher eflux speed....
Somewhat surprised that there would be no thrust difference. Just read in a German forum that a MPX Twister now has about the same thrust as w/ same power in Minifan after opening up the exhaust to 60mm (before, at around 53mm stock, it was down by an estimated 20% on the CS70). There are many such reports now, but things seem a bit more complicated and might depend on the inlet part?

Hope you find some more white noise, the Sapac T-45 is a beautiful model, it might as well sound good, too

cheers
Clemens
mopetista is online now Find More Posts by mopetista
Last edited by mopetista; May 14, 2012 at 04:53 PM.
Reply With Quote
Old May 14, 2012, 04:01 PM
Registered User
Thomas Nelson's Avatar
Calgary, Alberta, Canada
Joined Sep 2002
2,925 Posts
Interesting.

I can confirm at least part of this from my own experience.

I have a Minifan installed in my superlight Twister drawing 450 watts on 3S. Better than 1:1 T/W. Nowhere near the same T/W when I swapped out the CS10 also running 450 watts on 3S (3000kv $9.00 motor from HK). However I did not open up the nozzle.

I'm going to try that now! That was the whole reason for getting the 3S setup in the first place - putting it in my Twister.

tn

Oh, I should add that the CS10 on the bench pulled fine (no numbers mind you, just me feeling the pull on the test stand). It was clearly under performing once installed in the Twister.
Thomas Nelson is offline Find More Posts by Thomas Nelson
Last edited by Thomas Nelson; May 14, 2012 at 04:12 PM. Reason: Clarified subjective 'bench vs installed' thrust observation.
Reply With Quote
Old May 14, 2012, 04:22 PM
Registered User
anlucas's Avatar
Greece, Attica, Athens
Joined May 2011
3,553 Posts
Thanks for the feedback guys.

I should say that the thrust was measured statically. ie hang the model from the ceiling off the fish scale - nose pointing down.

I don't thing that we can compare other airframes.

It just so happens that this particular motor when run on 5S on the CS10 "seems" to produce the same static thrust with both 55 and 60mm appetures. I can tell you though that, although I have no way of measuring inflight speed, with the 55mm exit it was noticeably faster.

Next try will be with a 56-57mm exit.
anlucas is online now Find More Posts by anlucas
Reply With Quote
Old May 14, 2012, 04:58 PM
Registered User
Vienna, Austria
Joined Apr 2007
2,134 Posts
Quote:
Originally Posted by Thomas Nelson View Post
I have a Minifan installed in my superlight Twister drawing 450 watts on 3S. Better than 1:1 T/W. Nowhere near the same T/W when I swapped out the CS10 also running 450 watts on 3S (3000kv $9.00 motor from HK). However I did not open up the nozzle...
To be fair, the $9.00 motor in the CS70 will be > 10% below the very good efficiency of the (not so cheap) Mega you are running in your Minifan (I would estimate 80% vs. 70% at WOT), so you should also expect to get less power out with the same power in.
But it should be of the order of some 10%, not 30%...

Since Anlucas' T-45 was performing well w/ 55mm exit that might mean that the smoother thrust tube allows for slightly smaller diameter than would be efficient in a foam exhaust?
We will understand this fan eventually :-)
mopetista is online now Find More Posts by mopetista
Reply With Quote
Old May 14, 2012, 05:50 PM
Registered User
United States, TX, Grand Prairie
Joined Nov 2005
5,861 Posts
Quote:
Originally Posted by Thomas Nelson View Post
Interesting.

I can confirm at least part of this from my own experience.

I have a Minifan installed in my superlight Twister drawing 450 watts on 3S. Better than 1:1 T/W. Nowhere near the same T/W when I swapped out the CS10 also running 450 watts on 3S (3000kv $9.00 motor from HK). However I did not open up the nozzle.

I'm going to try that now! That was the whole reason for getting the 3S setup in the first place - putting it in my Twister.

tn

Oh, I should add that the CS10 on the bench pulled fine (no numbers mind you, just me feeling the pull on the test stand). It was clearly under performing once installed in the Twister.
HK motor has Smaller magnetic field, better for 5s on T-50 fan...4lbs of thrust on 5s\70 amps and the motor is being stressed...very light weight and inexpensive
erh7771 is online now Find More Posts by erh7771
RCG Plus Member
Reply With Quote
Old May 14, 2012, 06:00 PM
EDF rules... :)
AirX's Avatar
Joined Nov 1999
13,648 Posts
Quote:
Originally Posted by mopetista View Post
Somewhat surprised that there would be no thrust difference. Just read in a German forum that a MPX Twister now has about the same thrust as w/ same power in Minifan after opening up the exhaust to 60mm (before, at around 53mm stock, it was down by an estimated 20% on the CS70). There are many such reports now, but things seem a bit more complicated and might depend on the inlet part?

Hope you find some more white noise, the Sapac T-45 is a beautiful model, it might as well sound good, too

cheers
Clemens
I would like to put my two cents on this. It's no phenomena, the rotor is accelerating the flow a lot more than the average fan, the drawback is the rotor can't hold as much pressure, due in part to the blade design. The higher aspect ratio needed to allow more blades causes some efficiency loss.
The fix is to ease some of the pressure on the rotor by opening the exit area of the exhaust as has been shown.

Cheers,
Eric B.
AirX is online now Find More Posts by AirX
Reply With Quote
Old May 14, 2012, 06:55 PM
Extreme CNC Alloy EDF
Extreme_RC's Avatar
Australia
Joined Mar 2006
11,756 Posts
Quote:
Originally Posted by genghiskt View Post
Mark, Can look into the shipping cost, I find it cost too much for me even I m in Singapore. The air parcel cost from your site, I can ship a kilo of lipo from China by UPS.
Unfortunately shipping is fixed by OZ Post, nothing I can do about it, I added 5 spinners to the cart and it shows $12.25 to Singapore for airmail, thats as cheap as you will get it from here to anywhere.
Extreme_RC is offline Find More Posts by Extreme_RC
Reply With Quote
Old May 14, 2012, 09:13 PM
Registered User
Thomas Nelson's Avatar
Calgary, Alberta, Canada
Joined Sep 2002
2,925 Posts
Yep, totally understood Clemens! But this elcheapo motor/fan combo works well enough outside the plane that I think it's worth re-visiting with the Twister. My swap was several months ago now. I forgot all about the Twister until you brought it up again the other day. Now with this piece of feedback I need to schedule some day-surgery! I'll use some transparent film to make a cone. 60mm seems pretty big but I'll give it a try.

Quote:
Originally Posted by mopetista View Post
To be fair, the $9.00 motor in the CS70 will be > 10% below the very good efficiency of the (not so cheap) Mega you are running in your Minifan .....
Thomas Nelson is offline Find More Posts by Thomas Nelson
Last edited by Thomas Nelson; May 14, 2012 at 09:30 PM.
Reply With Quote
Old May 14, 2012, 09:24 PM
Registered User
Thomas Nelson's Avatar
Calgary, Alberta, Canada
Joined Sep 2002
2,925 Posts
Gotcha, & thanks for the suggestion! I was looking for a cheap, light, better sounding 3S combo to try with the Twister. While the bird could certainly handle the weight of a 5S pack up front and counterbalancing weight in the back, my goal from day one was to have an exceptionally light jet for higher risk flying like this.

I'll give the motor/fan a try and report back. Certainly the harder part will be opening up the nozzle without making a mess of things. I think I used epoxy to join the fuse halves, so it won't be easy sanding relative to the surrounding foam.

tn

Quote:
Originally Posted by erh7771 View Post
HK motor has Smaller magnetic field, better for 5s on T-50 fan...4lbs of thrust on 5s\70 amps and the motor is being stressed...very light weight and inexpensive
Thomas Nelson is offline Find More Posts by Thomas Nelson
Reply With Quote
Old May 14, 2012, 10:43 PM
Registered User
Australia, VIC, Melbourne
Joined Nov 2006
11,762 Posts
You should be able to use a piece of dowel (1" diameter or so) with sandpaper wrapped around it, to make it quite easy to work down inside the ducting.
Or even larger PVC pipe (2".. or whatever fits well), for more 'smooth accuracy of the rounding.
PeterVRC is offline Find More Posts by PeterVRC
RCG Plus Member
Old May 14, 2012, 10:52 PM
Kamikaze Ace
Glacier Girl's Avatar
USA, FL, Lakeland
Joined Jan 2010
2,387 Posts
Hmm, any chance the intake on the Twister is starving the CS fan, which in turn gives you similar thrust with different exhaust sizes?

It's all it can put out, as it can't pull in enough air?
Glacier Girl is offline Find More Posts by Glacier Girl
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
New Product Change Sun 12 blade 90mm Flip Flop Electric Ducted Fan Jet Talk 7112 Nov 30, 2014 12:33 PM
New Product Change Sun 120mm and new 10 blade 70mm fans Flip Flop Electric Ducted Fan Jet Talk 131 Apr 27, 2012 08:07 PM
Sold Change Sun electric retracts Flip Flop Aircraft - Electric - Jets (FS/W) 3 May 23, 2011 07:20 AM
Sold Change Sun Electronic retracts w/Lander struts hole digger Aircraft - Electric - Jets (FS/W) 2 May 06, 2011 02:27 PM
Sold Change Sun Electric retracts NIB 75.00 jzuniga Aircraft - Electric - Jets (FS/W) 2 Sep 03, 2010 10:36 AM