Topic: Building a jet drive lifesaving model boat advice needed please? (Read 5498 times)

ThamesAuxiliaryMarineServ · « **on:** August 16, 2016, 03:10:28 pm »

Hello, I'm very pleased to join the Model boat mayhem forums.

I would very much like your advice and guidance of possible to instruct me in building a lifesaving model boat.

It was certainly inspired by the E.M.I.L.Y, Emergency Integrated Lifesaving Lanyard, in the YouTube video link below.
http://youtu.be/56Ck_-ER3yE

However after talking with Hydronalix, the company who make them, the price for the EMILY is £7,300 or $9,500 plus import tax.

Now I'm sure it is a well constructed hull with durable electronics, as it's designed to be launched from a helecopter as well as by hand from the shore, but as a volunteer group we simply cannot afford such an expense at the moment.

So I would like to learn to build a similar version myself.

Now, I know little about electronics nor remote control technology, but I'm slowly picking up the basics as we would like such a model boat for our operations in Flood, Swift water and River Thames foot patrol.

So I am wondering if anybody here can give us some advice starting from the beginning.

I guess I will have to find out the hull chine shape and design and learn about battery powered jet propulsion and construction.

I am wondering if there is a hull similar to the one in the video that I can adapt and fit a closed cell floatation buoy upon and install Jet pumps to cope with the 5-6 knot tide in the tidal River Thames.

I shall look out for a three channel remote control handset, but any suggestions would be welcome and much appreciated.

And also if someone can possible recommend a make of a hull for this project then that would be a great help to get us started.

Perhaps maybe even if a model boatbuilder could be recommended to assist with the project also.

But general advice is very welcome too.

It's a pleasure to join the forum, as I was a little lost with solving the design challenge.

Kind regards,

Alex.
T.A.M.S

g6swj · « **Reply #1 on:** August 16, 2016, 03:27:19 pm »

Hi Alex,

Wow - what a great project - I wish you well with the challenge.

Does the RNLI have a similar tool here in the UK?

Regards
Jonathan

ThamesAuxiliaryMarineServ · « **Reply #2 on:** August 16, 2016, 03:37:52 pm »

Thank you Jonathan,
No the RNLI doesn't use these remote controlled lifebuoys as yet.
But we work with the RNLI upon the Thames, so when we build one they may adopt using them. I think if they do then they shall be able to afford the products from Hydronalix but the TAMS will have to learn to build their own versions.

I was trying to post a few photos of the hull shape from my iPhone, but my pickup app has stopped working and I'm trying to HTML my photos from my phone.
Still working out how to do so.

Still it's an interesting project for me, learning how to construct or adapt a suitable model jet drive remote controlled model, even if I am a little in the dark at the moment as to the technology and process.

Thank gord for hobby forums.

ThamesAuxiliaryMarineServ · « **Reply #3 on:** August 16, 2016, 03:47:42 pm »

ThamesAuxiliaryMarineServ · « **Reply #4 on:** August 16, 2016, 03:51:52 pm »

Apparently it's a 22 degree deep Hull, according to their website.
Still having problems posting photos from my phone. Shame that pickup photo app isn't working anymore.

Cheers.

g6swj · « **Reply #5 on:** August 16, 2016, 03:53:42 pm »

Alex,
You will certainly get some great advice on this site. Clearly the solution needs to be reliable and that does involve some planning.

the jet drive wil be a challenge - suggest you call Adrian at Speedline models- (just google) he is just in the process of starting manufacturing of some for the new RNLI Shannon models he will be releasing - he would be a great place to start

I have some Graupner Jet 5 drives no longer in production - maybe you could get some of them - I would suggest some forum members have got the gathering dust in their dens - again Google graupner 5 - this would give you some info.

EMILY is four foot long

Regards
Jonathan

ThamesAuxiliaryMarineServ · « **Reply #6 on:** August 16, 2016, 04:00:12 pm »

Will do Jonathan and Thank you. 👍

ThamesAuxiliaryMarineServ · « **Reply #7 on:** August 16, 2016, 05:08:17 pm »

For anyone interested here is a link to some photos of the type of remote controlled boat we wish to build or have built for us.

Thanks.

http://emilyrobot.com/portfolio-gallery/photo-gallery/page/3/#lightbox/4/

g6swj · « **Reply #8 on:** August 17, 2016, 06:56:51 am »

Alex
Looks like they are using Futaba pistol grip RC set normally used for RC cars.

Have a look at www. Wheelspinmodels.co.uk and select the tab electrics and then transmitters

This will give you an idea of what's available in the RC pistol style

Most RC kit now works on a 2.4ghz radio frequency which is great but you should note that the radio signal does not pass through water which may need some assessment should you be operating where there are waves - although perhaps not on the Thames!

Can any forum members add their experience / thoughts about 2.4ghz and potential signal dropout in water where the waves are big enough for the boat to temporarily disappear?

Regards
Jonathan

ThamesAuxiliaryMarineServ · « **Reply #9 on:** August 19, 2016, 08:01:24 am »

Thanks Jonathan,

Yes, I think I may use a conventional remote control handset rather than this wheeled version. I'm sure it's done simply to make it easier for the people who are used to helming a vessel but I don't mind using a regular handset as their will be enough training for the operator using it.

Would you agree a regular, conventional handset would proof better?

However I would like a waterproof handset, if they are available, or to seal a regular handset to make it reasonably water resistant.

One more question, does anybody know of any remote control model boatbuilder clubs in the London area where I may be able to go for a chat and ask for some assistance?

I think I may certainly need some help with this project.

I may need an overseer or team to contribute to the design and project, if anyone would like to share the project with the Thames Auxiliary Marine Service.

It's great to discuss it here on this forum as it keeps the project alive and not fade into a pipe dream.

Thanks.

C-3PO · « **Reply #10 on:** August 19, 2016, 09:40:26 am »

Alex,

I would suggest that you might want to consider a custom RC handset in the long term. As this is potentially a life saving device I guess that the spec of all components may need a different level of thought as to that of a model. In the short term for test purposes you can get something circa £50 which would work just fine for evaluation purposes.

I am unaware of any model RC kit that would be waterproof and indeed some are built into fairly brittle plastic cases. I guess it's also possible that you may be operating in difficult, dark environments so to have rugged, chunky, simple and possibly illuminated controls may be of benefit.

This is the style of control that I mean. It would be a fairly easy to make a custom RC set once functionality is specified.

PS Could you let us know a little more about your organisation (TAMS) - is it a charity, volunteer outfit or commercial? What type of things do you do?

Regards
C-3PO

ThamesAuxiliaryMarineServ · « **Reply #11 on:** August 19, 2016, 10:10:39 am »

Thank you C-3PO,

Yes a customised waterproof illuminated handset would be great.
For evaluation purposes I may use a trigger control after all, after reading a thread about them here.
http://www.modelboatmayhem.co.uk/forum/index.php/topic,54457.0.html

The Thames Auxiliary Marine Service is a Volunteer Organisation/Unincorporated Association started by members from the Maritime Volunteer Service, who we still work with, to support the RNLI, Emergency Services and assist in times of maritime emergency and safety.

We really On my way! The idea of a remote control lifesaving buoy, but Hydronalix versions are too expensive for us at £7,300, so we are trying to build our own version.

C-3PO · « **Reply #12 on:** August 19, 2016, 10:25:16 am »

Alex,

I would steer (excuse the pun) away from pistol grip - I am sure I will be corrected if I am wrong ( I have never used one).

The "trigger/wheel" is pushed/turned one way for forward and the other way for reverse. This is great for a car but I don't think you will have a need for reverse on your vessel - indeed a jet drive reverse involves the movement of a reversing bucket to redirect water flow underneath the vessel - the water flow through the jet drive does not change.

I think the pistol grip will cause you more heart ache and lead to confusion and possible electrical problems ( how the ESC Electronic Speed Controller interprets the instructions it's given (just my opinion).

So putting my money where my mouth is I am happy to donate a TX/RX ( not sure what's on the shelf but I think it's a Planet 5 ) - to your organisation that I don't use - you would not want to use it long term but it will get you going.

Regards
C-3PO

ThamesAuxiliaryMarineServ · « **Reply #13 on:** August 19, 2016, 04:39:49 pm »

Thank you for the advice and guidance C-3PO, we shall certainly follow it.
Your right, we have no need for reverse on our design, in fact we shall have a long line attached also for recovery.

That's most kind of you for the donation of a Planet 5 transceiver/receiver, it would be very much appreciated to get us started with research and development.

Well can we send you the money for the postage and a drink for your good self?

We have much to learn but everyday we are learning something new.

At present we are currently planning on building a 22 degree Deep V hull from 6mm marine plywood using the Stitch and Glue method and shall cover the hull with glass or carbon fibre.

We have much to learn about servos and connections, but we shall learn.

I'm wondering if there is a good book for building remote control jet drive model boats or is the internet the best way to learn tried and tested methods.

A lot of trial and error, but once we have cracked it we can build one for every crew.

I feel a bit like Barnes Wallace at the moment and I haven't even got my soldering iron out yet. lol

If we can send you the money and address we would greatly accept your kind offer of the Tx/Rx handset please.

Much appreciated and Thank you.

Kind regards,

Alex.

17-21 · « **Reply #14 on:** August 20, 2016, 04:52:03 pm »

this is the sort of water jet you could try, having used one myself it pushes lot of water.

http://www.cornwallmodelboats.co.uk/acatalog/graupner_2347.html

ThamesAuxiliaryMarineServ · « **Reply #15 on:** August 22, 2016, 04:42:26 pm »

Fantastic, Thank you 17-21.

If two members, yourself and Jonothan recommend the Graupner unit 5 then that's the one I shall use.

May I ask, is there a recommended Motor to use with the Graupner 5 please?

Much appreciated,

Alex.

17-21 · « **Reply #16 on:** August 22, 2016, 05:52:31 pm »

http://www.hobbyking.com/hobbyking/store/__24853__Turnigy_AquaStar_T20_3T_730KV_1280KV_Water_Cooled_Brushless_Motor.html

would be a good start

or http://www.hobbyking.com/hobbyking/store/__524__59__Electric_Motors-TURNIGY_RotoMax.html

esc
http://www.hobbyking.com/hobbyking/store/__25608__Turnigy_Fatboy_V2_300A_ESC_4_15S_OPTO_.html

some bits to have a think about also if you want a hull made speak to Andy at http://www.modelsbydesign.co.uk/
been doing it all his life, he also builds full size ones as well.

Phil.

ThamesAuxiliaryMarineServ · « **Reply #17 on:** August 22, 2016, 06:19:23 pm »

Thank you Phil, that's certainly put us on the right track.

I was just researching 1200+ motors with a high torque rate (5kg+)

I saw the Graupner ULTRA 1200-2000 in the manual for the Graupner Unit 5 recommended by Graupner of course, I suppose they would do.

After reading the Graupner manual in the link.
https://www.graupner.de/mediaroot/files/2340_JET_Antrieb_en_fr.pdf

So slowly learning the required specs. Next onto servos and Lipo batteries. 👍

I think we will build a 4-6mm plywood hull coated with glass fibreepoxy resin. We can convert the Glen L X1 plywood stitch and glue plans. It comes in at 40"/101 cm LOA and 16"/40cm beam which seems to be a good size for the floatation device atop the hull.

https://www.glen-l.com/designs/special/modelx1.html

The bow may need lowering in the conversion but that shouldn't be much of a problem being plywood taken from full size paper plans, so no lofting needed.

Thanks again Phil, this recommendation has helped speed things up in the design thinking.

Cheers.

C-3PO · « **Reply #18 on:** August 22, 2016, 09:03:26 pm »

Alex,
PM sent
C-3PO

ThamesAuxiliaryMarineServ · « **Reply #19 on:** August 22, 2016, 11:12:21 pm »

Thank you C-3PO.
Much appreciated.

Kind regards,

Alex.

ThamesAuxiliaryMarineServ · « **Reply #20 on:** August 23, 2016, 09:38:16 am »

I do have a question, if anyone could advise.
If I use a Graupner ULTRA 2000 to power the Graupner Unit 5, would it need to be toothed geared reductioned. I'm not sure of the correct RPM's for the Unit 5 relating to the Ultra 2000.

It says in the manual that it is to assist battery efficiency. Has anyone have experience with toothed gears for electric motors please?

Kind regards, Alex.

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Author Topic: Building a jet drive lifesaving model boat advice needed please? (Read 5498 times)