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Low Cost 120mm EDF Power System Possibility

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Low Cost 120mm EDF Power System Possibility

Old 11-17-2010, 07:55 PM
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Greg Covey
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Default Low Cost 120mm EDF Power System Possibility

Hi all,

I have successfully mounted the Castle/Neu [link=http://www.castlecreations.com/promos/motor_clearance/motor_clearance.html]1717-1500KV[/link] Brushless Air motor into the Haoye 5” (127mm) [link=http://www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=4235]OR003-00113-7B[/link] Ducted Fan making a potentially viable 3500 watt, 10-12lb EDF power system for only $100. ($70 + $30). Add an ESC (to be determined) on 6s-8s LiPo and you have a very powerful EDF system for relatively low cost.

Note that the 4.5" (115mm) fan will also work but I am not sure about the 4" (102mm) fan as it does not state the motor diameter it will handle. The Castle/Neu motor only needs some slight sanding on the outer metal heat sink fins before it can fit into the 49mm opening of the Haoye fan.

I'll keep you posted as I continue work on it...

Old 11-17-2010, 09:11 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

where did you get a motor this size for that price?
Also, do you have a method for balancing the rotor that you could explain a little?
My hobbyking 70mm rotors are useless, I can't get them to run without hitting the duct.
Old 11-18-2010, 07:52 AM
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Default RE: Low Cost 120mm EDF Power System Possibility

The link to the Castle Creations Clearance Sale is on the 1717-1500Kv in the first post or [link=http://www.castlecreations.com/promos/motor_clearance/motor_clearance.html]here[/link]. It appears that they have a good quantity of this heli motor and a much larger quantity of the 1717-1580Kv motor meant for cars. The main difference is a 5mm shaft so I decided to test that one out as well on another fan unit (to be determined).

I'll post data logging graphs from my ICE Test ESC when they become available.

As for balancing, you are one step ahead of me so stay tuned...
Old 11-18-2010, 08:01 AM
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Default RE: Low Cost 120mm EDF Power System Possibility

Wow!!!

3,500 Watts!!! You da man Greg!

Watching with interest!

All I have is 64mm and 70mm EDFs.

Would like to get a larger EDF someday and this thread is right with my style of tinkering!

Way to go!

Carlos
Old 11-18-2010, 06:12 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

While its always commendable to get a setup at a good price, 10lb thrust is easily obtainable from a 90mm Midifan PRO with an ARC motor on 8 cells at 3200 watts.

Now you say 3500w on 6-8 cells, thats a pile of amps burning up there, I doubt an ICE100 would stay icy very long To hold 3500w on 8cells means 120A draw andwill require some REALLY good batteries, sorta negates the cost savings

I think someactual figures are needed before everyone runs outto buy these motors.
Old 11-18-2010, 07:42 PM
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Greg Covey
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Default RE: Low Cost 120mm EDF Power System Possibility

While what you said has merit, anything can be swayed when taken out of context. My suggestion of using an ICE 100 was just an example so try not to take every word verbatim until I can post some numbers. I tend to post as I go so I don't have all the answers at this time. It is my way to have fun.

Looking at your own vendor site, you sell the ARC 3675-1.5 1160Kv for $139 and the MIDIFAN PRO 90mm FAN UNIT for $80. Running on 12 cell 4000mah 25c pack the 3675-1.5 runs around 3500 watts and produces around 44-45,000rpm for around 4.5kg of thrust. That's $219 for the motor and DF, plus the cost of 12 LiPo cells. Just another solution.

- - - - - - - - - - - - - - - - - - - -

I balance my rotors, when needed, using the Dubro [link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=DUB499]Tru-Spin Prop Balancer[/link]. I will sometimes sand the heavier blades but also spray the lighter blades with clear Rust-oleum paint or use clear nail polish to help balance them.
Old 11-18-2010, 07:47 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

Well, I believe Greg is on a good lead for an inexpensive power system that may work out and I am sure he will check it out carefully before any magic smoke comes out.

Just to give you all an idea of how much they are asking for the identical motor that Greg is using in this thread then, go to:
[link]http://www.amainhobbies.com/product_info.php/cPath/1_221_1359/products_id/160957/n/Neu-Castle-1717-1-8-Brushless-Motor-1500kV[/link]

Motor Specifications
Max Input Voltage 25.2V

Amp Rating 120A

Weight 20oz (567g)

Motor Diameter 45.95/49.95 w/fins

Motor Length 85mm

Shaft 5mm

Bearings Oversize ABEC-1 Front/Rear

Connector 6.5mm Gold



Oh, Greg....if you are looking for another motor of this same type then, go to:
[link]http://helifreak.com/showthread.php?t=257253[/link]
Old 11-19-2010, 08:06 AM
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Default RE: Low Cost 120mm EDF Power System Possibility

Yes and our pricing is in AUD as we are in Australia, plus it includes shipping a USA motor to Australia and local taxes.ARC have upped the price this month to USD$130.00 so our price is low now

And you cannot compare a wemotec fan made in Germany and dynamically balanced by a tech in Germany, to a cheap chinese fan. I have plenty of the Haoye 90mm fans here in a big bag, never used them and likely wont, the rotors are mostly molded out of round and not as efficient as a midi rotor and for me its not worth the effort of machining and balancing them.

I have nothing against putting together a great budget setup, I try to do it all the time, albeit with parts that are available all the time, the motor you listed is being run out so its not a regular $70.00 item, and I still think listing up guesstimations on a forum is dangerous, there are many who would take that as being proven figures and go out and buy the gear only to cook or destroy something.

By all means list the parts and the specs, but wait until you have it running on the bench before committing to figures, it protects you as well as others
Old 11-20-2010, 09:30 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

I see my posts have been reported and the first post of the thread has been edited. Seems contradictory to me.

To whoever reported my post/s I am not attacking another vendor or bashing the product.

I was very clear and polite in my first post, I did not mention any of my own products in my FIRST post, I simply listed up a well know combo used by many around the world, and the motor happens to be from a USA company too....

I could take Gregs reply to me as inflamatory and attacking in bringing up my products (when I did not), and then trying to pick them apart pricewise to defend himself...

I have noticed my posts deleted in the past from your threads Greg, without any notice or explanation.I post up facts and I deal with figures, I leave emotion out of it and I keep it polite. I never deny that RC is my current business, but I happen toreside in AUSTRALIA, I dont have many US customers, so the 50% of my time spent in US forums can hardly be labelled as "business time".

Many readers know RC & electronicsis also my hobby for 25+ years and I build and fly ALL this stuff because I love it, I spend a lot of my own time and money testing gear and breaking it because thats what I love about it.
Old 11-20-2010, 10:24 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

Mark don,t worry about the pettiness of the threads. I for one like to see your stuff that you have done. No need to do it your self if some one already has the info to put up here.

I like to see the stuff I don't have the time to do my self.

Don't take it to personal some people just like there threads to stay right on topic clean and neat.


Mike
Old 11-21-2010, 07:43 AM
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Greg Covey
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Default RE: Low Cost 120mm EDF Power System Possibility

Mark,

Please don't assume that I delete your threads or reported you. These are invalid assumptions. Although I am listed as a moderator, I haven't performed those duties in years as I just don't have the time.

I modified my first post because I considered your point about not making my posts clear and I wanted to correct that. Sometimes there is assumed knowledge that I just miss. Please don't analyze every post here as it increases the noise level. You tend to read tones that are not intended. As a vendor, you need to pay extra heed to not making it look like you bash products that you don't sell. I stay in my threads and I would appreciate the same courtesy.

- - - - - - - - - - - - - - - - - - - - - - - - - - - -

The rotor, adapter, and spinner all seemed to fit well. There is sufficient gap between the blades and the fan housing so that there is no possibility of rubbing. I think using an inrunner on this fan is a better solution than an outrunner because the snug fit makes the inner chamber very solid and removes the forces on the mounting plate; reducing distortions.

Once I receive my 6.5mm bullet connectors, I can start the testing...
Old 11-21-2010, 10:35 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

I NEED a BALANCED 70mm rotor for my setup. weak link in an EDF, is the rotor. Must be true, to get a true 45,000rpm (really 39.600 on my HET 69mm)
Old 11-21-2010, 10:59 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

Based on my experience with the 70 and 90, I guess I must say that in a 100 or 120 or 127 the rotor must be balanced and true. That seems to be the king of performance. I personally cannot dynamicly balance a rotor/spinner. I simply don't possess the equipment. and a balancer is where I can start, but it will fall short, I know. Can anyone produce balanced rotor systems like the HET 69mm rotor? If a machine shop dedicated some effort to the weak link in an EDF...well.

The Extreme_RC guy has alot of good equipment, meritable. I'm looking at spending more money, just to get the desired efficiency. I've just wet my feet in EDF's, but I've been modelling over 40 years and R/C since 1979. I have quite a bit of skill. However in a thing rotating at 45,000rpm, no matter what it is...centrifugal force is huge for the slightest gram of imbalance.

I would pay 25-30USD for JUST THE ROTOR! A solid motor mount would be cool too!
Old 11-22-2010, 08:02 AM
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Default RE: Low Cost 120mm EDF Power System Possibility

You have definitely hit the issue on the head when it comes to fan selection. Mark eluded to it before...basically you get what you pay for.

I have had the best success when using a dynamically balanced rotor. My examples were the WeMoTec Midi Pro 90mm, E-Turbax 120mm, and Lander 120mm DF. I do not know anyone that offers a mail-in dynamically balancing service. The equipment is very expensive! I know that Larry White from JHI (aka JHH) sends his rotors out to be balanced.

This does not mean that you cannot reasonably static balance the DF yourself. The two key areas are how well the adapter fits onto the motor shaft and how well the blades are balanced. Further, you can test the balance at lower powers while viewing and feeling the vibrations; power down, make a quick change, and repeat. These steps should always be done with safety in mind. Wear goggles and run the system behind a protective shield until it is ready to install in a model.

Alternatively, you can use the motor and DF that suits yours needs and then upgrade the rotor. Sometimes this can be cost effective. The idea of this thread was that the Castle/Neu 1717 motors will fit into the Haoye fans with little effort. Upgrade as desired.
Old 11-22-2010, 05:01 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

Just a small point, yes Wemotec rotors are dynamically balanced, IE they are put on a balancer and balanced for motion, they use an epoxy putty in them. Same with HET but the problem with HET is the inserts in the front and rear of the rotor can be pressed in badly if you are unlucky, and the collet can be a real pain to get running true with the rotor, take a lot of work to get the HET running perfect whereas the wemo adapters are incredibly well made and everything just fits together.

Lander on the other hand are not dynamically balanced at all, they are harmonically balanced, Lander takes a rotor out of the bin and fits it, tests it, adjusts the position relative to the shaft adapter until its running as smooth as they can get it, then they add the spinner cap and rotate it until the parts are all harmonically together. If they cannot get it perfect they try another spinner and so on and so on.
This is not proper balancing, and if you move the spinner cap the fan will vibrate instantly...Also the lander rotors are not as efficient as a wemo, they started out with wemo clones but something went down legally and they stopped with the clones and went with a chinese design. The chinese rotor is similar on the bench in tests but in the air its slower.

Static balancing comes down to quality of your gear, I have dynamic balancing equipment and I have very specialised precision ground tooling for static balancing, I can balance a rotor statically and then assemble a fan that runs so smooth you wouldnt bother checking it dynamically. Your biggest issue with static balancing is holding your parts dead centre, most magnetic balancers are junk, the shafts that come with them are never straight and the tips are never ground 100% dead centre. You need to make your own shafts or have a machine shop make what you need.
Old 11-22-2010, 07:28 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

Mark,

Thanks for the clarification. I know that the E-Turbax rotors are dynamically balanced, but by an outside facility.

Do you know how the Lander 120mm rotor is balanced? I was surprised by just how smooth it runs in my VERTIGO Rebel.

Also, is only the Wemotec 90mm Midi Pro dynamically balanced or is their 70mm rotor also balanced?

Thanks.
Old 11-22-2010, 11:53 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

AllWemotec rotors are balanced the same, even the little 50mm is balanced now as I went to do one last week and found green epoxy inside it. Lander "may" be statically balancing their rotors on the big fans before they fit them, their rotors are better molded than Haoye so they actually are centered on the bore, that in itself makes it easier to balance them. Of course they could still be using the harmonic method, only way to find out is strip it and look, bet you dont want to do that just for curiosity's sake!

The 70 and 90 also run very smooth when assembled from the factory, when you have a parts bin with 1000 rotors etc to choose from its cheapest to just swap things back and forth, time is not such a big cost inChina. After I ordered a pile of spare parts from them in 2008 and got a box of unusable rotors (looked like all the rejects they couldnt get to run smooth) I asked specifically how they were assembling and checking the fans, this is how I know. Whenever a Lander fan breaks we just fit Wemotec rotor and adapter to it, ends up being a better performer to boot!
Old 11-23-2010, 09:12 AM
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Default RE: Low Cost 120mm EDF Power System Possibility

ORIGINAL: Greg Covey
I have successfully mounted the Castle/Neu [link=http://www.castlecreations.com/promos/motor_clearance/motor_clearance.html]1717-1500KV[/link] Brushless Air motor into the Haoye 5” (127mm) [link=http://www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=4235]OR003-00113-7B[/link] Ducted Fan making a potentially viable 3500 watt, 10-12lb EDF power system for only $100. ($70 + $30). Add an ESC (to be determined) on 6s-8s LiPo and you have a very powerful EDF system for relatively low cost.
What do you think aboutCastle/Neu1520 -1600 kV- it holds the same current\voltage but thecase and fins are smaller?

there are also cheap hobbyking motors- not sure about quality...



Old 11-23-2010, 05:56 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

Mark,

Thanks for the info...but I'll pass on the bet.

I will, however, ask Tim Wan for a 120mm rotor and 5mm adapter to test on the second motor below. We can check it out then for balancing signs. I also want to see who will be selling spares for that unit. I don't know if anyone sells spares for his 120mm unit in the US.

Sansan,

You pointed out several other possibilities...thanks. The 15 Series motors seem to have a 42.5mm diameter compared to the 49.5mm diameter of the 17 Series motors. The HK KB45-08XL has a 45mm diameter so you would need to shim the two smaller diameter motors for a solid fit in the Haoye DFs. I haven't tried any of these motors so I figured I would try the 17 Series. Castle seems to have good quantities of all these motors (around 200) and a larger quantity of the one below (around 400).

- - - - - - - - - - - - - - -
I received the 1717-1Y-1580 motor and it has some slight differences over the 1500Kv motor. There are no flat spots on the case and the shaft is 5mm instead of 6mm. The end cap is very nice and supports longer Castle Creations silver wires. Both motors have the 6.5mm bullet connectors pre-installed.

I don't know what these R/C car guys do with these things but the motor is built so rugged that it would seem difficult to damage, even in a crash. For a size comparison, I put the 1717 motor next to one of my Neu 1415/1.5Y (1500Kv) motors that can handle around 2500 watts.

Since the shaft size on this motor is 5mm, I will plan to use a rotor upgrade on the second Haoye 5" DF. I'll look into the Lander 120mm rotor and maybe an E-turbax rotor which costs around $85 for the combination impeller, 5mm adapter, and spinner.
Old 11-23-2010, 07:33 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

Trying to tread lightly here LOL.

Sansan the problem with the motor you listed is the KV is just really high for a 120mm+ fan, most 120-127mm fans run 630-800Kv on 12 cells. Going up to 1100Kv on even 8-10s pulls considerable amps and means you need much more battery than the lower Kv 12s setups.

Also the price on that motor means you could just buy yourself an HET 700-98-670Kv or 760Kv which is cheaper, and has an 8mm shaft already, and is known to perform well in 120-127mm fans on 12s. Three 4s packs can be used as well.

Gregs motor choice comes down to price, if it was double I doubt he would bother as there are other options out there better suited. If he can get it to work on whatever cells at a reasonable amp draw then its a bargain, but if the motor was 150 bucks ++ then you suddenly have a lot more choice, even the Scopion 4035-630Kv is very popular for the bigger fans and not that much more in price.
Old 11-23-2010, 07:35 PM
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Default RE: Low Cost 120mm EDF Power System Possibility



double post, delete if needed!

Old 11-24-2010, 02:54 AM
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Default RE: Low Cost 120mm EDF Power System Possibility


ORIGINAL: Extreme_RC
Sansan the problem with the motor you listed is the KV is just really high for a 120mm+ fan, most 120-127mm fans run 630-800Kv on 12 cells. Going up to 1100Kv on even 8-10s pulls considerable amps and means you need much more battery than the lower Kv 12s setups.


Hi!
the motors I suggested has near the same kV as the ones Greg playing with
And Het motor priced twice against Castle motors on sale
But thanks anyway - I'll think about 12 S setup

I'm new to big ducted fans - the biggest one I had was 3.5' on a self made wing

Old 11-24-2010, 05:27 AM
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Default RE: Low Cost 120mm EDF Power System Possibility

Sansan, the 1520 motor you listed is USD$169.00 and as I said the Kv is really NOT suitable for this size of fan.
The HET 700-98 seriesis USD$155.00 regular price, so still cheaper.

The HK motor you listed is part of a range of well known motors that cannot handle the power input, they have been tried in fans before, if you do some research you will see the 700Kv version has been used in the Haoye 127mm fan and most burn up fairly quickly. I have the KD45 700Kv version sitting here and it gets stinking hot after only a short period of running.

I have the Haoye 100mm and 120mm rotors sitting on my bench, I have run them in Alloy housings and I have run ramtec and Dynamax 127mm rotors. Even going from 670 to 760Kv raised the amp draw by 20+ amps and lowered the efficiency during some initial 120mm testing.
Old 11-24-2010, 10:43 AM
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Default RE: Low Cost 120mm EDF Power System Possibility

Mark,

I agree, I typically would not be considering a 6s-8s Lipo setup in a 5" fan but it is fun to experiment when the cost is so low. I think the confusion you are having with Sansan's 1520 selection is that his link was to the original price on another distributor site but Castle is now dumping them for $65 on their Clearance page.

As far as the differences in top end performance, I am uncertain about the 1520-1600Kv versus the 1717 (1580Kv) but agree with your assessment on the HK motor not performing long at the rated power level.

If I can get my setups to pull 120amps at max throttle on 6s to 8s, it seems reasonable to use a lighter set of 4AH 30C packs on an 8lb-10lb application.

Thanks for treading lightly...I enjoy reading your posts.
Old 11-24-2010, 08:29 PM
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Default RE: Low Cost 120mm EDF Power System Possibility

I mentioned the rotor balance and opened a can of worms, maybe for another thread, yet, I wanted to let you know Greg, that if and when (more likely, when) I get into 120's, I need to know if the rotor, of the fan unit is at all usable. Those Hoaye fans balancable? One thing of merit to your thread. Not me, or many old-skool R/C'ers want to spend the mega-dollar on high-end fan units. The area of concern to me is this:

For instance: in a 70mm fan for 5 minutes of flight I'm seeing that the thrust to weight ration is less than 1, unless you carry more pack (power)
So my assumption is that it's very difficult to get decent flying aircraft, because the AUW is usually greater than thrust, unless you only want 1 or 2 minutes of flight.

As we go up to 120mm fans:
What is the real scenario? Can the 1:1 thrust to weight be met, with 6 minutes of flight time?
Some of the old-skool guys need to chime in with the need for adequate, neat, proper DUCTING

Back to your thread, of LOW-Cost 120mm fan. I'd be VERY interested to see 18 lbs. thrust. I'd be EXCITED to see 14lbs. A 4.72" (120mm) Fan is big, but not that big.

Can any of you guys explain the application of a 120mm? AUW of the bird? Wing loading ranges? Physical sizes? And are we talking about 10 or 12 lbs. thrust?

http://www.espritmodel.com/index.asp...D&ProdID=13592

The TAMjet 120 has 10-12 static. Is the combination you're suggesting near that? By the way the TAM is way expensive. 450 for the unit 900 with a motor. LOL I'd NEVER spend 900 dollars on it. I need body work done on my 1992 Eagle Summit (LOL)

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