Thread Tools
Feb 21, 2017, 10:03 PM
Registered User
Discussion

Ultra light 5" build


I have a spare 3" quadrysteria rush that I no longer fly (also trying to sell) and was looking at it tonight and deciding what would be fun to try with it. So since I have a few 4s and 3s 800-1000mah batteries and the rush runs 2800kv 1804 motors, I'm considering doing a super lightweight 5" build reusing many parts I already have. The frame, FC and ESC are the lightest I could find the rest I already have but might look at some alternatives if they get lighter. I do know there will be some extra weight for wiring and screws/standoffs but I will minimize them by using all plastic screws and standoffs.

Note this is not initially intended to be a racequad otherwise I would be changing cam/vtx

Below is what I was thinking for the build, currently weighing in at 131g for all parts without batts. The batteries I have that I would try all range in weight from about 70g/3s to 105g/4s


Let me know what everyone is thinking will probably order frame and ESC/FC in the next week.

Frame (40g): QAV ULX clone http://www.banggood.com/Realacc-RFX1...p-1084776.html

Motors (64g): Quadrysteria 1804: https://quadrysteria.com/collections...s/products/541

FC/ESC (6.5g): Micro F3 and 4 in 1 esc: http://www.banggood.com/6_5g-XJB-V1-...p-1120103.html

Cam/VTX (5.6g): Kingkong cam&vtx from a Q100: http://www.banggood.com/Kingkong-Q25...p-1097798.html

RX(1.2g): FlySky FS-A8S: http://www.banggood.com/10-Pairs-Kin...p-1067875.html

Props: Kingkong 5040 triblades: http://www.banggood.com/10-Pairs-Kin...p-1067875.html
Sign up now
to remove ads between posts
Feb 21, 2017, 10:51 PM
humayraykinaon's Avatar
Quite a list you got going here one thing I wouldn't consider buying is the FC/4in1 esc, that has 20x20mm mounting hole, were as your frame is 30.5x30.5, probably better picking one of this instead.
http://www.banggood.com/Eachine-Falc...rmmds=category

I do have that cam/vtx,, but I would go for 200mW for better range and since you want to stay light consider this
http://www.banggood.com/600TVL-14-CM...rmmds=category
http://www.banggood.com/Eachine-VTX0...rmmds=category
Last edited by humayraykinaon; Feb 21, 2017 at 11:08 PM.
Feb 22, 2017, 02:10 AM
Registered User
fretman's Avatar
I've been wanting to try a build just like this. Very interested in how the 1804 motors would handle 5" props and flight times. Subbed!
Feb 22, 2017, 05:17 AM
Registered User
Quote:
Originally Posted by humayraykinaon
Quite a list you got going here one thing I wouldn't consider buying is the FC/4in1 esc, that has 20x20mm mounting hole, were as your frame is 30.5x30.5, probably better picking one of this instead.
http://www.banggood.com/Eachine-Falc...rmmds=category

I do have that cam/vtx,, but I would go for 200mW for better range and since you want to stay light consider this
http://www.banggood.com/600TVL-14-CM...rmmds=category
http://www.banggood.com/Eachine-VTX0...rmmds=category
The extra weight of that FC and ESC isn't worth it (6.5g vs over 20g). I have a 3d printer so will just print a 30.5x30.5 to 20x20 adapter. I'll actually print it from TPA so that it gives some dampening to the FC and will act as a soft-mount (kill 2 birds with one stone).

I actually have a spare switchable Eachine VTX03 sitting unused so I can use that if need be but the range on the king kong I have listed is very similar in my testing on a smaller 2.5" build.
Last edited by DMCfirestar500; Feb 22, 2017 at 06:12 AM.
Feb 22, 2017, 05:19 AM
Registered User
Quote:
Originally Posted by fretman
I've been wanting to try a build just like this. Very interested in how the 1804 motors would handle 5" props and flight times. Subbed!
Yes me too. I think the 1804s from Quadrysteria should work great. I was looking at the racerstar 1804s but the spec sheets don't look as good. They are cheap though at about $5ea so I may get a set of those and give them a try as well. I'm pretty confident that something this light will have no problem with those motors. I'll also try this build with 4" props as well if the motors get hot at all.
Feb 22, 2017, 08:58 AM
Registered User
I'm going to put this build on hold for a while as my 3" rush just sold so I will no longer have the 1804 motors or a few of the batteries I had planned for this.

I was also thinking HGLRC may be coming out with a V2 of the ESC that will support BLHeli S with D shot and after flying that on most of my quads I'm not sure I want to build one that does not support it.

Definitely not dropping this build and I have a feeling many racers will be moving to ultra lightweight builds like this sooner than later. Regardless of what Joshua Bardwell, etc say about heavier being better the advantages of going light as possible always outweigh ( pun intended) the minor angle/speed advantage of being heavier on a tight (or probably any) track.
Feb 27, 2017, 09:19 PM
Registered User
Another update, I haven't given up on this build however 1804 motors will not work on this frame they (atleast all of them I've been looking at) have 12mm spaced mounting holes where this frame only has 16mm spaced holes. The 165mm version has 12mm spacing however could only run 4" props. So now i'm looking at light 1806 motors.
Feb 28, 2017, 06:36 AM
Brisbane, Australia
Eachine EB185 B1806 2300kv weighs 19gm and performs well, the best for the weight and price that I've come across so far.
Feb 28, 2017, 08:07 AM
Registered User
Good recommendation was also looking at some sunnysky x2204s 2300KV they perform well and only weigh 21g ea.
Feb 28, 2017, 12:19 PM
Registered User
fretman's Avatar
Quote:
Originally Posted by DMCfirestar500
Good recommendation was also looking at some sunnysky x2204s 2300KV they perform well and only weigh 21g ea.
I use those on my quads(250gr w/o batt), going 1806 didn't seem sensible as weight diff was so small.
Feb 28, 2017, 04:22 PM
Registered User
Have you looked at the dys se1806... they are a bit heavier at 21 to 23 grams but can get at 2550 kv and holds 312watt or so... i have the same build in mind.
Mar 02, 2017, 07:20 PM
Registered User
Going with Lumenier Skitzo 2204-13 2500kv motors. Very reliable and only 21.5g.

Still up in the air on FC/ESC stack, the quad that comes with that stack has been getting terrible reviews but thinking a lot of it could be due to the 75mm wheelbase. I may end up going with a lightweight 20a 4-in-1 for now with plans on going smaller/lighter in the future.

I ordered 2 of the frames as well in case one breaks.
Mar 03, 2017, 08:04 AM
Registered User
I will keep an out for this thread. For how much lighter the the fc esc stack is it might still be worth it... If this quad is meant for racing you just need to go fast and not care so much if it is smooth or what not... That said i would love for a stack that light with dshot...
Mar 03, 2017, 10:07 AM
Registered User
There are some other 20x20 stacks that get better reviews just a bit more expensive. I'm keeping my eye out as I think in the next month or 2 we will see more and more come out as the sub 100mm brushless micros become more and more popular.

For now I'm keeping it cheap and I already have a few extra dodo boards which with a 4-in-1 esc I won't need a PDB so that will help keep weight down on its own (only a few grams) and the 4-in-1 I'm getting is only 19g and 5.4g for dodo so Its not terrible in weight.
Mar 04, 2017, 04:08 PM
Registered User
Getting further, just ordered 1 x tattu 450mah 75c 4s and 3x tattu 650mah 75c 4s packs. at 55g and 74g respectively this racing build is getting closer and closer...


Thread Tools