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Jul 05, 2019, 01:56 PM
world's slowest builder
Air-Jon's Avatar
That looks so sweet Par!!! 18S is a great way to go for SHV!
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Jul 05, 2019, 05:39 PM
Lee Liddle
Knife Liddle's Avatar
I agree. Very nice Par. I like the new front end set screws. No more tiny stripped out set screws. Really the complete package and perfect for many large turbine airframes.
With 10ah cells peak draw will only be 20c. Probably 5 min flight times with mixed throttle.
Jul 05, 2019, 10:10 PM
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70 ragtop's Avatar
Very nice!
Jul 05, 2019, 10:42 PM
HAL... Open the damn doors!
jfetter's Avatar
That's a sexy fan! So what is now left of what you started with, is the rotor still Dynamax? I am impressed!

Jack
Jul 05, 2019, 11:19 PM
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Thread OP
Thanks guys. It is a good looking piece of engineering and I never imagined that this would be the end product back when I started doing this over 3 years ago.

As to Jack’s question, the only stock Dynamax part that remains is the rotor blades. I have aspirations of producing my own CF rotor at some point but that’s a long ways away. For now, I think we have an excellent fan for 30lb class jets. I am eager to hear back from Mongo once he gets back from work as he will be using the prototype fan one of his jets.
Jul 15, 2019, 04:48 PM
Classic jets rule
AIR SALLY's Avatar
very nice looking Fan Par ...is the OD of the shroud the same size as the stock Dynamax Shroud at the inlet side ? just wanted to know as I make those inlet lips ,a Nacelle and inlet ducts for the Tams Jet A-4 to fit the Dynamax fan.
Jul 15, 2019, 10:11 PM
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Thread OP
Quote:
Originally Posted by AIR SALLY
very nice looking Fan Par ...is the OD of the shroud the same size as the stock Dynamax Shroud at the inlet side ? just wanted to know as I make those inlet lips ,a Nacelle and inlet ducts for the Tams Jet A-4 to fit the Dynamax fan.
Thanks! The OD is slightly smaller at 133.5mm and it is the same from front to end. I donít think you should change your molds. It would be much easier to 3d print some kind of adapter to use with this fan.
Jul 16, 2019, 05:26 PM
Classic jets rule
AIR SALLY's Avatar
yeah Thanks , that would be easy for someone to do .
Jul 16, 2019, 06:40 PM
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Warbirdmadman's Avatar
Par, do you sell a fan assembly with the HET 50mm motor? I am printing LYNXMAN's L-39 and would like a fan setup for it. It only requires a 10-12s setup, as it's only 16-18lbs

Thanks WMM
Jul 16, 2019, 07:06 PM
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Thread OP
Quote:
Originally Posted by Warbirdmadman
Par, do you sell a fan assembly with the HET 50mm motor? I am printing LYNXMAN's L-39 and would like a fan setup for it. It only requires a 10-12s setup, as it's only 16-18lbs

Thanks WMM
Yes, I have 18 sets remaining. They can be used with 50mm HET motors.
Jul 16, 2019, 09:27 PM
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Warbirdmadman's Avatar
Quote:
Originally Posted by Par_18
Yes, I have 18 sets remaining. They can be used with 50mm HET motors.
PM sent.
Sep 10, 2019, 09:53 PM
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Thread OP

Two updates and one video


Well, its long overdue but below is a link for the 18s test video. Today was a little "cool" for south Texas with ambient temps of about 90 degrees when I did this test run. Overall, this is a great setup and will make for some awesome 30lb jets. The ideal battery size for this is 3 X 6s10000mah/25c packs. I have come across some very cheap packs ($120/pack) intended for e-bikes that weigh in at 1400g per pack. This will easily give a 5-6min flight per charge with plenty of high speed passes. Of course, one could spend more on lighter batteries to keep it lighter.

The ESC being used to conduct this test is a brand new 22s/400amp version pictures below. This ESC is significantly better than the previous 22s/380amp variants. Not only did it remain extremely cool for this test (installed in a wind tunnel with 2 cooling fans). As can be seen in the pictures, the ESC uses dual 8awg wires for the battery terminals, which really helps at this power level. The motor has also been a solid performer as I have been running it for a couple of months now with many test runs.

Additionally, after over a year of staring at the boomerang, I managed to get it all together and have now flown it 5 times. The first two flights were done using a 12s fan putting out 17.5lbs of installed peak thrust with an AUW of 24.2lbs. Last weekend though, I dropped my 16s (20.5lbs installed thrust) V2 setup in there raising the AUW to 26.25lbs. I was a little nervous about the total weight but the jet is a great flyer. It slows down so well that it is almost unbelievable. If I had to guess, the top speed is around 120-130 with very good vertical. It flies and sounds just like a turbine. If the intake situation could be improved on this jet, I would instantly gain another 2lbs to thrust. This 16s fan only pulls 130amps at peak so even with 6000mah packs, 5 min flights are very doable. I found myself landing with the packs at 3.8v/cell after 3 mins of flying. I'm going to make a video of the jet this weekend both onboard and from the ground so you guys can check it out. I do plan to sell this jet soon to make room for a faster sport jet so be on the lookout if anyone is interested.

"Cat 6" Dynamax EDF w/TP-5690-585kv on 18s/6ah 65C Turnigy Graphene Lipo's (4 min 40 sec)
Sep 10, 2019, 10:27 PM
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erh7771's Avatar
That's the way a fan bench test is done !!!

How were the graphene packs after you got done? Were they cool to touch, did they go negative at all?

I was thinking of going 2 x 4000 mah CHL 6s parallel for longer flights but that would add up to the same weight as the 10 mah 6s you have mentioned in your post.

Looking forward to any testing with those packs.

The Top RC Odyssey still looks like a top contender for this fan cause of intake size and the way it flies.
Sep 10, 2019, 10:46 PM
Registered User
Thread OP
Quote:
Originally Posted by erh7771
That's the way a fan bench test is done !!!

How were the graphene packs after you got done? Were they cool to touch, did they go negative at all?

I was thinking of going 2 x 4000 mah CHL 6s parallel for longer flights but that would add up to the same weight as the 10 mah 6s you have mentioned in your post.

Looking forward to any testing with those packs.

The Top RC Odyssey still looks like a top contender for this fan cause of intake size and the way it flies.
The graphene packs are amazing. Max temp is around 120-130 deg depending on how hot it is outside.they are heavy but there is no way to get this kind of performance without weight.

The odyssey is exactly what Iíll be getting. Itís large enough to allow me to go all the way up to 22s, which is the intent. Iíll be ordering a motor for this test next month to find the sweet spot for 32lbs of peak thrust. I think we can get there at only 150amps on 22s.
Sep 10, 2019, 11:17 PM
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erh7771's Avatar
Quote:
Originally Posted by Par_18
The graphene packs are amazing. Max temp is around 120-130 deg depending on how hot it is outside.they are heavy but there is no way to get this kind of performance without weight.

The odyssey is exactly what Iíll be getting. Itís large enough to allow me to go all the way up to 22s, which is the intent. Iíll be ordering a motor for this test next month to find the sweet spot for 32lbs of peak thrust. I think we can get there at only 150amps on 22s.
I push mine in the 170s with a 24 lb turbine, I paired the model with that turbine just to test that theory about efflux with a turbine and volume etc.

Looks like 29 lbs of push can get the Odyssey moving along at a good clip.


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