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dilanski

Putting together a Rapidstrike

So after turning up to ZHoM with a Praxis primary (for the lulz), I have come to the conclusion that flywheels really are the master race, and that the Barricade did nothing wrong. So with that in mind, I have jumped headfirst into the world of money flying out of my bank account faster than I can reconsider.

Luckily I have a Rapidstrike that has been sat around since 2013, so that is some cash saved. But otherwise the list of items ordered so far is as follows:
*BSUK Switch & Wire Kit
*BSUK 3xHellcat's
*BSUK Motor Cover Set
*HK Turnigy 2200mAh 3S 40C Lipo Pack
*HK IMAX B6 50W 5A Charger/Discharger 1-6 Cells (GENUINE)
*HK HobbyKing®™ Fire Retardant LiPoly Battery Bag (170x45x50mm) (1pc)

Still need to buy a soldering kit, and need to figure out a power supply for the LiPo charger (The BSUK recommended link is broke Sad ). Will also need a dremel tool for cutting the shell.

So really this leaves me with two quick questions, firstly is there anything I am missing from my list? Any tools I should really have or any parts that are really useful for a Rapidstrike build. And secondly, does anyone have any images of the BSUK motor covers fitted? I have yet to open my blaster, but the cutting seems like it might be more awkward than I originally envisioned. Any other general tips for doing a Rapidstrike will also be appreciated.
Sparky2504

Which wiring kit did you get? With hellcats you want the High power one that includes the mosfet
BANTERMAN894

The soldering iron I use is this:
https://www.amazon.co.uk/d/Solder...11&keywords=soldering+station
dilanski

Sparky2504 wrote:
Which wiring kit did you get? With hellcats you want the High power one that includes the mosfet


And inevitably I've ordered the wrong kit.
NewportNerfer113

With 3 Hellcats you are going to need a better LiPo pack.  Something that can handle 65 - 70c at constant and a decent burst just in case.  

This is the one I have in my 3 x Hellcat build: https://hobbyking.com/en_us/graphene-1500mah-3s-65c-w-xt60.html

EDIT:
In an effort to be a little more helpful, here's Boff's awesome thread about motor / LiPo combos from The Vault: http://britnerf.myfreeforum.org/about3134.html
The Dark Kitten

Message BSUKs email and ask Mike if you can change it.
He is really helpful and can sort pretty much anything out
Sparky2504

NewportNerfer113 wrote:
With 3 Hellcats you are going to need a better LiPo pack.  


That pack should be fine, 2200mah at 40C should give you 88A constant, one thing you may have an issue with is the physical size and fitting it into the battery tray .
NewportNerfer113

Thanks for the correction, I've obviously got confused along the way.
Sparky2504

Formula for working out the current is
C × mah ÷ 1000 = Amps
SSGT

One thing that is missing from the list is a PSU for the charger. If you get the iMAX B6 you'll need one with a rated to a minimum of 50W (ideally at least 60W - the charger itself can only output 50W but the circuit inside will also use a bit of power/lose some to heat) that has an output voltage somewhere in the range of 11-18V and uses a 5.5x2.5mm barrel jack. Alternatively you can get a genuine iMAX B6AC or an Accucel S60 neither of which require a separate PSU.

Sparky2504 wrote:
Which wiring kit did you get? With hellcats you want the High power one that includes the mosfet


You don't necessarily need a FET with Hellcat flywheel motors (even though it's well past their design spec Cherry DC2s have been used with 180 flywheel motors almost since the RS was released) although if you don't/can't switch to the FET kit I, personally, would swap one of the DC2s (the one you'll use to switch the flywheel motors) with a full-size 21A switch (ideally a Cherry or Omron but the cheaper, half black half red, clones will also work).
dilanski

OK, order with BSUK is sorted. Now just need to wait for my packages full of goodies to start trickling in.

SSGT wrote:
voltage somewhere in the range of 11-18V and uses a 5.5x2.5mm barrel jack..


I have a Monitor supply that I think might work. It's 19V 3.42A, which according to what google tells me is 65W. Will the higher voltage be a problem?

On another note, I am thinking about the dentistry mod. No one by any chance has a 2D printable template? Or know where I can get a 3D printed/moulded part?
Boff

Yes, 19V will be a problem. The on-board capacitors probably won't thank you for over-supplying them.

I should probably get on a printed dentistry mod piece given what I have in mind for when I eventually do my own...
dilanski

All my parts have arrived, and I can't wait to get started.

I've got some 7.0mm Heatshrink from maplins, but I am not sure if it'll go small enough, anyone know if I should get something else to test with?

Also, what is the best way to test my motors? I haven't got my LiPo set up yet, so don't see using that as an option. Also, some of the tabs on parts are a bit bent (Motors, MOSFET), am I good to just bend these straight, or am I best just leaving them as is, and working around it.
Sparky2504

Best way to test is make an alkaline battery tray to plug in, should never check with a lipo first incase there's a short on the circuit
Minky

You can bend the motor tabs and the Mosfet pins straight if you want,  just bear in mind they are weak pieces of metal and don't pull the motor tabs too hard because I think (someone correct me) that you can accidentally yank them out/damage the insides.

Having said that I have been fairly brutal with Mosfet pins and got away with it (so far) to make them easier to solder/fit.
SSGT

7mm is a little excessive. The Maplin stuff has a shrink ratio of 2:1 (i.e. it will shrink to 1/2 it's original internal diameter) meaning it'll be a slightly loose fit on 16AWG (normally somewhere around 3.0-3.3mm OD) and a very loose fit on 18AWG (normally somewhere around 2.5mm-3.0mm OD). I don't think they are adhesive lined either so they rely on shrinking far enough to form an interference fit the wire. 5mm heatshrink is normally a good all-rounder, especially if it has a 3:1 shrink ratio.
Northwind

The big mixed sets on ebay are pretty good- it's not the highest quality, it doesn't shrink as fast or as much as some but they're cheap and it's a good range of sizes to figure it all out.

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