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11-11-2005 06:35 AM  12 years agoPost 1
morphs

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Salt Lake

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I am with CustomCdr. We make cnc machined cdr based outrunners for foamy airplanes. I want to be able to offer a motor for micro helis, but I need to know if they work well or not, before I dive into allot of R&D. Our airplane motors are very successful. We are getting over 20 oz. of thrust out of our sub 1 oz. singles at less than 10 amps and over 30 oz. out of our 38 gram doubles at under 15 amps. We also have a speed wind single that spins a 4" prop at close to 40,000 r.p.m. @ 13 amps..

I already have a design that would work great and it looks killer too!!
I just need to know about winds, termination types and pinions sizes on successful motors.
Any input would be appreciated, as I would like to get some new products out for helis.

Here is a pic of a few of our airplane motors.

Thanks,
Jon

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11-11-2005 10:50 AM  12 years agoPost 2
zrdcorp

rrApprentice

Caguas, PR

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I am not sure about thrust, but based on all the spec of the motors we normally fly in the T-Rex, we are looking at about 300W continuous capability.

Our motors use around 25A or more on a 11.1 application and are 80% to 90% efficient.

Roger's Law: If it is worth doing it, it is worth exceeding it.

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11-11-2005 11:23 AM  12 years agoPost 3
Paul_C

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Limpopo, South Africa

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I first flew my Trex on an AC DIY VL motor which I wound 6 turns, 6 strands, 0.3mm wire in star config, and it could handle about 160W on a 3s pack. It worked quite well and kept the Trex really light, but I think it’s Kv was a little on the high side, if I were to try again I would go for 7 turns.

If you can design a motor rated at around 3200Kv and 160W @ 3s, it would be a good beginners motor and should still provide enough power for aerobatics. If you can get it to 300W I think it would appeal to both beginners and advanced pilots. The average hover current/power of a 3s Trex is around 9A/100W


Will your motors be available in kit form?

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11-11-2005 02:19 PM  12 years agoPost 4
PJRono

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Minnesota, Ya!

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I made a GBx brushless for my T-rex. I used 13 turns of 24Ga wired in Delta Parallel. On a Triple+(3.5 stators JB welded together) Motor. You must use highspeed bearings(zz or ceramics) cause the standards won't last long. It has plenty of power and weighed 62grams. One other thing I did was to epoxy putty the spaces between the magnets in the can to keep them from flying loose(ask me how I know!!!!).

If you skip me I can't play!

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11-11-2005 02:48 PM  12 years agoPost 5
morphs

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Salt Lake

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Our bearings are ZZ rated(60,000 rpm)
We also use n50 curved magnets with 98% coverage. I have never seen or heard of one of our magnets coming loose. Even at over 35K

I think we have the mechanical side covered, we just need to get the right Kv and watts.

Thanks, Jon

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11-11-2005 03:06 PM  12 years agoPost 6
AnnihilaT

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The Netherlands

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If you can make something that can deliver 400 watts or more and weigh less than 100 grams at a kv of 3200-3500 i think you would have a real winner for 3 cells and you would sell ALOT of them. If you can figure a way that the user could easily resolder or rewire for a lower kv you would have another innovative best seller. This would allow people moving up to higher voltage setups to use the same motor.

Ok maybe im dreaming

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11-11-2005 03:10 PM  12 years agoPost 7
TheX

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Newport Beach, California

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What price range are you trying to provide?

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11-11-2005 03:21 PM  12 years agoPost 8
morphs

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Salt Lake

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I want to keep them comparable to our airplane motors. $45-$55

-Jon

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11-11-2005 05:38 PM  12 years agoPost 9
StrangeRanger

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VT

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Morphs,
You've got a good idea, but like everyone has said, the Wattage is going to be your sticking point. Helis are inherently un-efficient. They pull a LOT more current than foamies and other planes.
The other issue is that a lot, not all, but a lot of outrunners get hot and pull a lot of current. Most folks run a 35+ amp esc, and some run 25 amp esc's and outrunners seem to push the limits here. When consider we run 4 servos and the gyro we pull a lot of power. I'd be stoked to see what you come up with!

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11-11-2005 06:13 PM  12 years agoPost 10
WRXRonald

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Auburn, OH

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ok...

i really know very little about these little brushless motors (other than they make my bird fly thru the air ).... but wouldn't a 400watt capable motor just whoop on our 3s batteries?

i would think if you're making a motor that capable, give a much lower KV rating like 2100 or so, allowing for a HV type of setup that will make good use of all those available watts.

i NEVER could get a reading over 195 watts with my 3s Lehner setup.

but my 5s lehner setup spits out 295 watts. (of course that's tied down and 12 degrees pitch/full throttle... No WAY is it pulling those watts in flight, where the load is inevitably less 99.9% of the time.

just my thoughts on the matter, not sure if they mean much of anything or not................

Good Day: crashed thx to dumb thumbs. Bad Day: crashed mechanical malfunction. Every Day: CRASH :)

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11-11-2005 06:21 PM  12 years agoPost 11
AnnihilaT

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The Netherlands

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A motor capable of 400+ watts isnt the same thing as seeing it output that on your TREX, Ronald. Its a rating arrived at during testing of the motor and with 20C 2100mah packs capable of 42 amps continous, its not completely impossible.

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11-11-2005 07:37 PM  12 years agoPost 12
ced0

rrApprentice

Towanda, Pennsylvania

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i really know very little about these little brushless motors (other than they make my bird fly thru the air ).... but wouldn't a 400watt capable motor just whoop on our 3s batteries?
Watts = Voltage * Amps

A 3S setup would be 11.1V...so 400W = 11.1V * A...400/11.1 = ~36 amp draw. Have fun trying to get a battery that can do nearly 40 amps continuous.

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11-11-2005 09:56 PM  12 years agoPost 13
StrangeRanger

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VT

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To continue cde0's thot:
If you had a 3s pack say pulling 25A = 277.5W. So, if you're thinking your little Rex is pulling 400W you'd need:
400W / 11.1v = 36A and you're little puff ball TP 2100 pack would have to be crankin' at 36A / 2.1 (a 2100mAh pack) = 17+C continuously. I don't think so.

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11-11-2005 10:14 PM  12 years agoPost 14
jfint

rrApprentice

Simi Valley, CA

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I think that they mentioned 400W as a goal for high voltage setups, which it very attainable, with a 5 cell pack your down to 21 amps, pretty easy to get at.

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11-12-2005 08:47 AM  12 years agoPost 15
AnnihilaT

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The Netherlands

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I said capable of 400W ouput. Nobody said anything about a motor putting out 400W continously on a Trex. 400W peaks would be no problem on a 20C 2100mah pack. For that matter 400W continously is still under the ratings for a 20c 2.1 amp pack as 20C would be 42 amps continous.

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11-12-2005 07:26 PM  12 years agoPost 16
WRXRonald

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Auburn, OH

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well..

you guys can throw around all the numbers you want....

the bottom line in the real world is this.........

i've used the Tanic and TP pacs in 3s configs with a Lehner (300W max watt motor), and pulling WAY less than 195 watts continously, (MAYBE a very agressive estimate says that i have pulled 195 watts for 1% of a 10minute flight--- not very likely though) but at least for the sake of argument...... and the batteries were beyond there reasonable temperature threshold at the end of the flights 150-155 degrees, and despite relatively little overall usage from these batts.... they just don't have it 'going on' like they used to. i PRESUME its from over-heating them too much during the summer months.

Thus i re-soldered the lehner and went to HV setup.

Yes Anni i realize your special 20C batteries are more capable than the TP's and Tanics i was using...... but in my personal opinion, i still HIGHLY doubt they could stand up over time in the situation discussed in the last several posts.


HV if you plan to come anywhere near 400watts is the answer. (at leaset i'm convinced of that from my VERY little experience in this hobby so far).

like the rest of you, just voicing an opinion of course.

Good Day: crashed thx to dumb thumbs. Bad Day: crashed mechanical malfunction. Every Day: CRASH :)

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11-13-2005 12:52 AM  12 years agoPost 17
CRB68

rrApprentice

Tombstone, AZ

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Been there done that.

Built a double stator(22.7) and wound 10T 24G Wye Parallel. Flies the Trex just fine but I changed it out to a Mega 1615/4.

Amp draw was about 10 amps WOT and full collective. Did het warm though.

PJ

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11-13-2005 07:06 PM  12 years agoPost 18
WRXRonald

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Auburn, OH

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well...

thought i would post this here... Anni sent me a PM regarding this thread and i don't really appreciate 'why' we can't have this discussion in a public forum???

Anni, dude...... you should know by now you can and SHOULD say anything you have to say 'about' me or to me in the forum for all to see. your adverse opinion of my 'posts' lateley is not of much concern to me. i don't mind constructive critisism... but lets let everyone weigh there opinions regarding the matter so we can have some "FUN" with it at the same time......

the quote:

"Hi WRXRonald

I like you so im gonna do this privately and try not to offend you.

Dont take this the wrong way but i have noticed that you have been doing ALOT of speculating lately which isnt based on really anything solid or concrete and whereas you used to seem credible you are starting to look alot less credible lately. Take the 20C packs for example and the motor capable of delivering 400W max. You just simply are missing the point entirely and dont seem to realize it. Here we are in an area i think that is simply outside your realm of experience at this point but yet you continue adding input which just doesnt seem to make much sense.

20C packs. Im not the only one that has them. THey are all over the place now. Its NEW battery technology. I fly a lehner on 3 cells with these batteries now and they dont get hot whereas the first TP-2100 gen2's i had i pretty much killed from using them with the lehner. You say you doubt any battery can stand up. This just makes you look uninformed and a bit behind because of the many batteries out there which are rated for 20C now. 20C is 20C. If they are rated for 42 amps constant thats what they will deliver without causing damamge to the pack. Period. The manufacturer would not maintain a market and a customer base if they were selling a lie.

400 watt capable motor. Go have a look at this page:

http://www.justgofly.com/tech_450TH.htm

Go down to the 450TH charts. Look at the bottom of the chart. This motor is capable of 319 watts in bench tests (althought its paper rating is 250 watts).

Go have a look at this:

http://www.freakware.de/shop/artike...ow_artikel=9817


This motor is rated at 450 watts max.

So what im getting at is that you are making posts which more or less balking at the idea of any motor existing which could be rated for 400 watts on 3 cells when in fact they ALREADY EXIST. It's like me saying that ive tried to build a spaceship to the moon and had so many problems with it that i really doubt anybody else could ever do it.

Anyway.... the point of this message is twofold. I dont want to get into a discussion with you publicly about something like this since i think it would offend you but i thought you would at least be interested in hearing an outside opinion on some of your posts lately. I think its important not to take the attitude that just cause you havent seen it or experienced it than its not possible. That kind of know it all attitude gets annoying.

Hope you dont get the wrong idea about all this and if you want to discuss it im up for that - just dont take any of this personally. Its not meant as a slam on you or i woulda done this publicly.

Take care,
Anni"

are you afraid that support of my posts by the 'public' could outweigh the support of your posts?

either way i KNOW of others who feel you are the one who posts about 'nothing' like a 'now it all'. Although i NEVER confirmed or necessarily agreed with any such PM's that came my way. i took them for what they were, simply informational posts regarding peoples' opinions of your posts and threads.

that said..... i'm beginning to buy it more now. no one likes a 'now it all' who accuses another of being a know it all. (pot--kettle--black?)

now before this gets out of hand, Anni i too have always liked you and not had any trouble with ANY of your posts whether i believed them completely or thought they were complete BS. Nor did i ever try to 'call you out' (privately or publicly) when i did disagree with something you had to say.

much of these forums are often based on theory, opinion, educated guess, and experience. that's all i have ever posted, and we all assign a certain amount of 'reliability' to certain peoples posts--- that's all we can do in a public forum.

i NEVER mislead my opinion--- i made it QUITE clear which batteries i was using and what my situation and background of experience was. ANYONE then has the option to assign as much 'weight' to comments as they so choose. you for instance, have made it clear that you assign little weight to my assessment of the above discussed situations, which i have no problem with.

simply state your opinion and assessment of my post IN the thread so all can see and make their OWN judgements about whoose information you choose to believe or not.


Now i'm sure there are some reputable sources here that WILL refute your blind support of supposed "20C" capable batteries. (hmmm, sell these batteries do you?)


look dude--- there's HUGE money in lipo batteries market, the dealers and distrubutors are in it for PROFIT, they will say anything within reason to SELL batteries. They ALL put their spins on the batteries themselves and i FULLY support that your 'special' 20C batteries are probably MUCH more capable than GenII crapp Thunder Power batteries, HOWEVER, i KNOW manufactures INFLATE the 'C' capability of their batteries on frequent occasion.

so you say 42 amp continous no problem from your 20C batteries... i just don't buy it, if you ran them like that for 10minutes I'M PEROSONALLY CERTAIN they would overheat, i base my opinion on PURE speculation based on the fact that your batteries are coming from 1 of the 3 same sources that everyone elses are. if i'm wrong, so be it, but certainly you owe it to the forum and readers to go ahead and prove me wrong with NUMBERS and do it publicly, so all can make the 'correct' assessment of whose info is more reliable, and whose isn't. i just simply posted my opinion based on my experience of lipos so far, last i checked, i was allowed to do that, and you're allowed to be annoyed by it. right or wrong, it is what it is, i NEVER said it was anything different. great if you can back your opinions up with facts. i commend you on that. i can say that my 3s lehner NEVER pulled more than 21-23 amps PEAK and still the Lehner severely weakened and overheated two TP 2100's and two Tanic 2220's. TP's rated at 10-12C continuous SHOULD have no problem if they are truly capable of what they're rated-- thus i DOUBT the numbers given on these batts. i've not tried yours, (never will actually), but i would not trust them too much more than i trust TP's... simply for the fact that they are indeed LIPO batteries, made by the same cell manufacturers as everyone elses.

who makes the cells you are selling as 20C Anni?


-- sorry for the major thread hijack folks... i just can't help myself.

Good Day: crashed thx to dumb thumbs. Bad Day: crashed mechanical malfunction. Every Day: CRASH :)

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11-13-2005 10:01 PM  12 years agoPost 19
PJRono

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Minnesota, Ya!

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WRXRonald I would have to agree with you about the LiPO situation. I think the manufacturers are just looking for the BEST NUMBERS they can get and publishing those. They have to make themselves sound good with all the batteries on the market! I too have tried to run LiPOs the way the manufacturer suggests and everytime it has ended in trashed LiPOs which gets spendy in a hurry. Sure they may hold up for about 10 flights (best scenario) but all end up in the permanent filing bin.

If you skip me I can't play!

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11-13-2005 10:07 PM  12 years agoPost 20
PJRono

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Minnesota, Ya!

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I would also add the same about motor manufacturers also. NO DISRESPECT INTENDED to the above or others. Manufacturers will always opt for the best stats. They may be obtainable but is that how the product will really be used?

If you skip me I can't play!

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Helicopter
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