recommissioning / finishing my HPR 115

[vvviivvv]

Hi guys,

been a fair few years since I last visited, don't know how many remember but I have a hpr115 ive had for years, plagued with issues it never ran correctly and after burning another boat down I kinda shelved it,

Now a navigation officer (well for the last few years) on a boat with 3x 20MW electric motors I think it's time to finish this thing off,

The build from what I remember was a hpr115, HPR running gear, NEU 1521/1Y (will have to 2x check) and as26-150 ESC's props I have a few from propshop and also some x447's "tongue cut by Andy brown"

I have no idea what im getting myself into so need some solid advice on getting it operational, I need a new radio, batteries and a few other things.... it also need's a few finishing touches,


Anyway, some pictures where it currently is, the issue I had at the time I couldn't get the boat to plane / make any speed.

[vvviivvv]

To get us started, what is the current go to radio / receiver setup for fast electrics?

And Lipo's, what brand should I be running? I've often thought my old batteries couldn't supply the power I needed...

I will need some assistance with mounting the battery tray's, to get a good COG,

Do I go 5s/6s? I modelled my setup off what a lot of European boats at the time ran which I believe was a lehner 1950/7.... this is all from memory..

[vvviivvv]

Also, at this point, if there was anybody in the UK with twin cat experience who would like to take on finishing this off... I'd be inclined to drop it off...

[fweasel]

I would suggest flipping sides on the flex cables and props and change the wires on your motors so the props spin inwards. Hard to tell exactly, but it looks like your drives are setup with quite a bit of negative trim angle, which will push the nose of the boat down, running wet. That will slow your speeds and could be part of your initial running troubles. I don't know enough about those NEU motors to know what kV they are and what voltage you should use with what size prop. As for battery trays, you can go simple with a long, precut carbon tray that will give plenty of room for lipo adjustment from the rear of the motor forward. You would wrap them with velcro straps lengthwise and would just need to move the straps to a new set of holes each time you moved the packs to adjust your COG. Depending on your speed goals, COG on fast cats of this size (100mph+) can often be around 40%.

Shawn, srislash, has a HPR115 he just finished building and is in the process of tuning. He'll be able to help you out on the weight setup.

[vvviivvv]

The angles of the struts are just where I left off last time, probably 5+ years ago.....

I believe its a '1y 1577' rpm motor.. the plan was 6s at the time.

I have adjustable battery trays, hopefully srislash can chime in and I can get them positioned and glued correctly...

Any recommendations on a new controller / receiver, and Lipo brand?

I literally have no idea and just jumping back into it all...


I will flip the props around, thanks.

[vvviivvv]

So far from what I remember...

Hacker used to be good batteries, is that still the case or is my money better elsewhere?

https://www.nexusmodels.co.uk/hacker-topfuel-power-x-6s-5000mah-35c-lipo-battery.html

Also, controller wise,

https://www.nexusmodels.co.uk/spektrum-dx5-pro-5-channel-dsmr-transmitter-with-sr2100-spm5010.html

How does it work with carbon hulls and antenna's, i installed a antenna for my old setup, I can't just cut and attach a 2.4ghz reciever to that from what I can remember? what is the solution...

Also to add, it is a full carbon hull.

[StevenBryant]

Hi Liam

Batteries are important as I’m sure you are aware, the best and easiest available are SLS QUANTUM from stefansliposhop.de in Germany, great service even better batteries... I run these in all my boats now, and are going into my two twins I’m building.

In the UK there are no expert twin builders, just a few people like me with a small amount of experience.


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[StevenBryant]

Great motors and perfect for a nice 8s setup, unfortunately you’ll need to upgrade your esc. I would make up a two cap banks for the esc to help them..


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[vvviivvv]

A lot has changed since I was last here,

SLS have come down a lot in price, will go with them... is 8s not a bit 'hot' ? I'm not after any saw records just anything in the 80mph range would be nice...

the controller is rated 4s-8s I guess its the amp side it wouldn't take it ? although I do remember them being run on big saw setups with 22 series Lehner? or maybe i'm mistaken.

theres a NEU powered boat on the old youtube, 2300kv on 6s x447's making 100mph..

Maybe 7s could be the one?

I'd like to be sure before I start purchasing batteries in all honesty, if im going to have to also start shelling out for new ESC's

[srislash]

A lot has changed indeed, good stuff is much more accessible. I don’t see why you couldn’t hit 70-80mph with 6s and those motors. I have a couple lesser hulls running that with the same’ish KV and 6s. My HPR has Lehner 1691kv’s on 6s and is around that speed with 447’s.

Thanks Ryan BTW And here is the last vid of my HPR

https://youtu.be/ciaCIMZ_mUA

[vvviivvv]

Just read all of your thread actually :)... particularly like how the hatch mounts.

from what ive read today, the 22 series lehner is more like the 1527 NEU, but I hope a 1521 has enough to swing some 447's,

I'd like to achieve a running boat for now, something I can charge the batteries up take out for a spin.

Later maybe I will start experimenting with higher cell setups if I can just get a 'cruising' setup working...

[srislash]

I should add that I did have a dickens of a time getting this one up on plane in a straight fashion but I found the fix in my case.

[vvviivvv]

That was part of my issue... boat never broke onto the plane.

this was the expory you said you are using? I need to completely restock.

https://www.mbfg.co.uk/sp-gruit-handipack.html?gclid=Cj0KCQjwnKHlBRDLARIsAMtMHDEPItud8TFXjvbHkvKgmmcGTn4xxWGRj11O91cWipeC5S_C4XAicnUaAjq9EALw_wcB

Once I work out the battery situation ill get them ordered, I've emailed the esc manufacturer to get the correct settings for the NEU motors,

You are running props inwards? At work we do so ill go with that I think :)

Kind regards,

[srislash]

In my case the not breaking on plane correct was in my ESC settings, once I went to ‘fast’ start in settings it was fixed. That still perplexed me but it’s what it was.
The 1521’s should have no issue with 447’s!
That epoxy will set pretty quick with only a 8 minute pot life. You may want something a bit longer ? It depends what you have left to do. The battery sliders can be put in with silicone, that what most of us do.

[srislash]

Definitely adjust the drives to a more neutral setting. Here are mine from the 447’s

C3B90B3D-67D5-4451-9557-2AB1F4340DE0.jpg

And if you find yourself not wanting those ESC’s I would have interest in them.