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Brushless Rayven Update & Chrono numbers
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Flint McCrae
New Member


Joined: 29 Dec 2016
Posts: 8
Location: North West UK



Post Brushless Rayven Update & Chrono numbers  Reply with quote
Hi all.

Here's an update on my brushless Arduino-controlled Rayven, first posted here.

Since then I added a couple of tactical items:



Originally I simply used the rotating outer can of the outrunners as a flywheel.  I've added these smooth concave flywheels to the second stage.  The first stage still uses the outrunner cans.



I got my hands on a Xcortech x3200, and did a couple of quick tests - the results were mixed.  With worn Koosh Gen 3 darts I saw an average of 102fps.  Using fresh Koosh Gen 3 velocity was much higher averaging 132.3fps.  With Ekind x-tip waffle darts performance was woeful, 65.9fps average!

Here's the full results and chart:



Next job is to try tweaking dart crush so it will play nice with waffles.
Sun Mar 19, 2017 4:13 pm View user's profile Send private message
SirBrass
Junior Member


Joined: 06 Mar 2017
Posts: 55
Fav. Blaster: 180 Stryfe & 180 Rapidstrike
Location: California, USA



Post Reply with quote
That is odd to be getting such woeful performance on the x-tips. Did you notice dart burn or other signs of energy loss (that should have been translated into increased forward velocity but was extended otherwise) on the darts?

With brushed 180 motors and worker flywheels, I get well above 100 fps on fresh and worn x-tips. Brushless DC motors that have proper concave flywheels that fling koosh that well I'd think (key word) would fling an x-tip similarly but with only about a 5-10 fps loss due to weight.
Sun Mar 19, 2017 4:37 pm View user's profile Send private message
Northwind
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Joined: 28 Dec 2014
Posts: 899
Fav. Blaster: Rapid Red
Location: Edinburgh



Post Reply with quote
Yeah, likewise- I don't have the numbers to hand but IIRC I saw about 135fps out of koosh and around 110-120 out of the best x-tips. Actually out of everything I've tested, nothing's got close to the difference you have there.

That's with stock crush, I'll be doing some shots with an openflywheelproject high crush cage in the next few days hopefully so I'll see if I can find some new xtips to throw into that

More importantly though, awesome blaster!
Mon Mar 20, 2017 11:28 am View user's profile Send private message
SirBrass
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Joined: 06 Mar 2017
Posts: 55
Fav. Blaster: 180 Stryfe & 180 Rapidstrike
Location: California, USA



Post Reply with quote
Could be that the flat tip is revealing an alignment issue that the elites & kooshes had no issue getting around.

I would have guessed that it'd been a distance issue between the two stages but that wouldn't explain the gross differences between koosh speeds & x-tip speeds, so my guess is that it's an issue of the x-tips feeding into the second stage. Maybe they don't like the distance between the two stages & you need to bring the stages closer together?

I'd look at alignment first though.
Mon Mar 20, 2017 5:44 pm View user's profile Send private message
Flint McCrae
New Member


Joined: 29 Dec 2016
Posts: 8
Location: North West UK



Post Reply with quote
SirBrass wrote:
Could be that the flat tip is revealing an alignment issue that the elites & kooshes had no issue getting around. .


Yes, I think this could be what's happening.  I'll be checking alignment during the next tinkering session Smile

UPDATE:

Changed the flywheels today for this serrated design fore and aft:



With Xtips there's an improvement, but they still won't play nice with this blaster, averaging a measly 98 fps and peak of 144.  I'm using quite a tight-fitting brass barrel, has anybody tried similar with x-tips?

I'm very happy with the Koosh numbers though, here's what the same Xcoretech said:



EDIT

Posts merged. Please don't double post instead either edit your previous post or, to also bump the thread, copy the contents of the old post, delete the post and paste it into a new post along with the new content.

SSGT


Sat Mar 25, 2017 7:50 pm View user's profile Send private message
SirBrass
Junior Member


Joined: 06 Mar 2017
Posts: 55
Fav. Blaster: 180 Stryfe & 180 Rapidstrike
Location: California, USA



Post Reply with quote
There's your issue. Tight fitting brass barrel is slowing down the darts way too much. Tight fit brass is for springers, not flywheelers.
Sun Mar 26, 2017 6:26 am View user's profile Send private message
chris_ngale
Junior Member


Joined: 13 Dec 2016
Posts: 32
Location: Cambridge/Durham



Post Reply with quote
While I have no direct experience with this exact issue, one thing I can say is that in my experience Waffle darts very frequently jam inside breach loading brass barrels which Elites, Koosh darts etc go through just fine - I think the significantly longer and slightly wider tip means that they produce just that bit more friction than narrower tipped darts. As such I'm not particularly surprised that if they're being flung through a narrow barrel they're slowing right down, elites brushing the side will contact with a tiny bit of rubber and a lot of foam, waffles will contact with a whole lot of rubber.

Awesome project btw, I love seeing a good brushless mod


Sun Mar 26, 2017 10:31 am View user's profile Send private message
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