Discussion Sniper II construction and discussion thread

[Kai_Shiden]

Yeah, these new higher C batteries are definetly testing mechanical and electrical limits that we hadn't run into before. I would trust >15T pinions to 1.5KW with proper tight mesh, but that's about it, approaching 2KW and above I think doubling up the maingear might be in order (unless you are good with collective management).

As to which motors to advise, I don't do that anymore unless I myself have run them (it just takes far too much effort to get a true feel for what a motor will do from calcs and spreadsheets, the only real way to find out is to buy one and try it , theory just isn't close enough to reality).

-Kai

[mahbouni]

Originally Posted by Kai_Shiden

the only real way to find out is to buy one and try it , theory just isn't close enough to reality

So expensively true

[Kai_Shiden]

I will say that I want to try out a Hyperion HS3026-880, they list it as a Protos upgrade motor: http://media.hyperion.hk/dn/hs/hs-spec.pdf

It's not so expensive it will break the bank: http://www.allerc.com/product_info.p...oducts_id=4831 ($74.80)

At least with the Protos sharing similar KV requirements, there are going to continue to be options... (That, and these low KV motors work out fine in medium size electric planes, of which I also have interest in going too).

-Kai

[mahbouni]

The Hyperion HS3026-880 is a rebranded Scorpion HK3026-880, the same motor I currently have in my Sniper II. It didn't run so hot in my Protos but I found it a bit heavy and upset the CG with my 6s 3300mAh packs.

Actually all of the Hyperion HS series are rebranded Scorpion HK motors. I have this confirmed by the UK importer for Hyperion.

[Kai_Shiden]

Well that's a bummer (especially since I don't like Scorpion motors), comparing the numbers, they are identical (except for a discrepancy between idle amps).

Edit: then again, one of the things I hate is gold motors , so I might still do it just for the matching blue ...

-Kai

[mahbouni]

I think probably Hyperion do some of their own testing for the data specs, but the physical constants are identical.

[mahbouni]

Anyone seen this and know what improvement its supposed to make?

http://www.laheli.com/web/product.ph...rade Sniper II

[Kai_Shiden]

Sweet, that kit should allow adjusting the hiller input between 3 settings. The blade grip arms are a faster ratio (or you could stay with the stock blade grip arms and just pick up precision), and the alloy mixer arms should lessen flex (necessary for the increased bell input).

Basically it looks like it's for more tuneability options for the flybarred head (ie, won't be of much use to those who have FBL Sniper II setups).

-Kai

[mahbouni]

They also have the conversio kit for 15mm servos, which means that decent servos (e.g. DS3517, DS3405 or DS9650) can be used.

http://www.laheli.com/web/product.php?model=2&pid=808

[Kai_Shiden]

Looking at it further, I was mistaken, those aren't mixer arms, they are the ends of the flybar cage (the hiller adjustability of 3 settings is still the same though, and the blade grip arms having increased throw is also correct).

Pete posted something about this kit a while back when Matt was noticing that too high of throws were causing links to pop on his standard head.

-Kai

[Kai_Shiden]

Here's a link to Pete's picture of the 15mm servo conversion kit: http://www.rcgroups.com/forums/attac...5&d=1245953918

And here's a link to the assembled pic of the 3D Expert head upgrade: http://www.rcgroups.com/forums/attac...2&d=1249223053 (Of note, the multiple hiller ratio holes weren't visible in the original pic).

-Kai

[mahbouni]

I seem to remember Pete posted a diagram for a frame mod but I didn't know it was available as an upgrade. I just spaced the frame sides out with washers so I could get my 12.5mm servos in but 15mm is a whole new incentive.

How would you adjust the hillier ratio?

[Kai_Shiden]

Originally Posted by mahbouni

How would you adjust the hillier ratio?

By moving the ball links on the flybar seesaw in or out (that's why 3 holes, 3 ratios of how much the hiller bar inputs to the bell/hiller mixer).

It may even be possible to utilize that along with flipping the bell/hiller mixer on the grips for different bell ratios as well (as opposed to only being able to adjust the flybar "output" ratio only).

Honestly, I would have to have the system physically in front of me mounted to a heli before I can verify full range of movement clearance with all different variations.

-Kai

P.S. On my Sniper v1, I turned down the hiller ratio by flipping the ball joints around on the flybar and sliding them in a little from their stock positions (fine tuning to make it neutral in FFF instead of wanting to keep accelerating). My Riccos are the same way, in their case I sanded the flybar seesaw to reduce the hiller ratio (also for more neutral handling).