RC India

This is my first RC project with a correct Radio and servos. All my previous one were using radio from RC toys, had a lot of limitations.I gathered a lot of information on Radio's and servos from this forum.

I am building a Atlas van Lines Boat. Plans available on  Thanks to VKsingh for helping me convert the plan to a tiled one.
Heres photo of my Radio that I bought from srihari(sriharishine). Great guy to deal with. He first sent the Radio to let me check before paying. Thanks Srihari!

And of course my friend and guide Ashish Lampuse(ashJR7202) for helping me with the electric selection and other guidance. Calling Ashish is like pressing F1.
Thanks Ashish.

Here are the photos of the build. I am building this boat with a 4 mm Hard Advertising Board. I got this from my office. I thought this material has same strength as Balsa, and also does not break. Would be glassing it in the end.
Would be using the following electric
1) Brushless 2025 14L inrunner. would be water cooling this.( Again a Thanks to Ashish for sharing this motor)
2) 30 A ESC
3) 1600 mah 3S Lipo
4) 9 gm Servo
5)  Kyosho Prop equivalent of Octura X431
6) Would be using a two wheeler speedometer cable as a flexible shaft.
7) Epoxy Fast


First assembled the Transoms with the stringer. Then went on to Glue the Sponsom Bottom. and the Tunnel Strip. Next would be to glue the Tunnel Bottom.

Shreekant

Some more photographs

Some more photos

Hey shreekant!!!!

it looks grt yaar!!!! chalo jaldi jaldi complete karo would like to see it running!!!!!

do u think it needs some carbon fiber reinforcement???!!!!

Ashish

Thanks Ashish,
I would be reinforcing the two stringers with Balsa. But I am sure that Glassing would add enough strength.
shreekant

:thumbsup: The waterproofing and tests of the same would be interesting to see !

Always exciting to see boats on the forum! I have some of this advertising board lying with me and was wondering where to use it. Thanks for showing the way. I have wanted to build one of these lobster boats for a long time. Do share your glassing details, material used and techniques with us.

All the best! :thumbsup:

VC

Nice piece of work there!
Looks very good, I am sure the outcome will be a good high speed monster.
Will you use Thermocol blocks inside the hull for flotation?
Cant wait to see this ready!

Regards,

Dorwin

Thanks VC and Dorwin.
Shall post the glassing by week end. The structure would float by itself. It would not require any additional floats.

Shreekant

The idea to use speedometer wire will not work appropriate for you, cause speedometer wires are made to run at low rpm and not meant to transmit axial thrust. When it is force to rotate at higher rpm a lot of turbulence may occurre at propeller as well as motor end. Instead of using speedometer wire try with two number of propeller shaft at rare end coupling both shaft with a spring.

And sorry I was late answering the handmade propeller as I was in tremendous work pressure since last one month. I will post some videos within a few days.

Had a 2 hour long conversation with Maharana today, in which we ate each others brains out from Sailboats to Submarines. Couple of points to note here, as informed by Maestro Maharana:

1. Best try to make the two shafts out of bicycle spokes (Even Saikat advises the same), I have used it with great success.

2. The coupling spring will be available with any photocopier engineer. When they strip a copier, they are left with a lot of springs that they throw away. These springs are PERFECT for prop couplings. Don't try to use Ballpoint pen springs for this purpose, they will give way at high speeds.

Don't thank me, thank Maharana/Saikat for this info. ;D

Cheers!

VC

See the main idea to use a flexible shaft in model boat is to position the propeller horizontally so that the max. thrust from propeller pushes the boat in a forward direction, because an inclined shaft wastes much energy in lifting instead of pushing the boat forward. But if the inclination / angle of slope is less than 15~20 degree, fine. So it is better to use a straight single shaft with less slope than a flexible or a joint shaft. 

Coupling shafts is surely a good idea

Some doubts.Why would there be a turbulence at the ends of the speedometer wire.The speedometer wire would be supported with Nylon bushes at both the end.( bush in the stuffing tube).
The doubt arises because the speedometer wire and the flexible shafts available from HK look to be the same.
If you could highlight the difference between the two.

Shreekant

Actually I don’t know what kind of flexible shaft, clamping units and its accessories are used in model boats, but the use speedometer wire as flexible shaft at higher rpm creates a lot of doubt. So it would be better to make a test of it by temporarily fixing the rc unit, flexible shaft with clamps on a plywood, and see the result at higher rpm.


And read a conversion on this subject :
http://forums.radiocontrolzone.com/archive/index.php/t-180465.html

Got to complete the toughest part this week end.bottom planking. The boat shape has come out to my satisfaction.Had to re-cut the side sponson sides, since the earlier ones left some gaps. The rear sponson were relatively easy to glue. Also I realized the advertisement board does not react to Feviquick. It does not eat up the board like coro.So used feviquick to put the planks into place and then used epoxy to cover the gaps. Would be completing the centre plank and the rear bottom this weekend and also would be completing the glassing.

Got to speak to Maharana yesterday... Got some Awesome ideas on coupling from him. Good to get connected with people like him here.

here are some pictures of the boat

It is shaping up nicely.

Post your build log pics man!

This week just managed to fix the bottom plank of the boat. Went out to look out for the Fibre glass cloth with Ashish in heavy rains. Found a factory manufacturing Fibreglass pipes in Airoli. They were willing to fibreglass the boat for us. But we weren't sure on the quality of work that the  workers in the factory  could do. so decided on doing it myself.Bought a 2 meter fibreglass finishing cloth from them for Rs.20/per meter would use two layers of the same.
They also had the other fibreglass  cloth which was relatively very thick. Would be using Epoxy diluted with a nail polish remover to do the glassing. Will post pictures soon.

Also received my new Turnigy Accucel 6 charger and Lipo from HK this week.

After a lot of experiments with the Flexible shaft I have decided to drop it. since, I have realized that I need tomake the complex stub shaft arrangements at the prop end.No patience for this. Hence I have now decided to go ahead with a solid shaft.Made one myself from SS with a SS stuffing tube. Also made the drive boss from SS. Got access to a small workshop nearby my place to make all this. Used a 3mm SS rod for shaft. Also have installed a 'O' ring at both the ends to prevent the grease in the stuffing tube from flowing out.
As for the rudder used a stapler front piece for the rudder holder.

Before I installed the hardware I also went for a float test of this. Couple of places  water seeped in. This will be taken care off during the glassing.
 Will be taking up the glassing once I have completely positioned the hardware.

Since this is a surface drive unlike the submerged drive..water line would be cutting through the prop hub. Heres more details on the same.  http://www.well.com/~pk/SPAprofboat.html
More pics of the hardware.

This is really beginning to look good!

Everything is looking fine  :thumbsup:, just want to know:
(1) Expected weight of the boat after fiber glassing.
(2) Position of the propeller underneath water, I mean below waterline.

 

The approx weight should be around 600-800 gms. And the prop axis is parallel to water with the waterline cutting the centre of the prop.

wow!!! now it has started taking shape!!!!!

Surface Piercing Propellers, is what you are refering and even if you keep the weight below 1.5 kgs it will become a very fast moving on water. 

Some how though I am not too happy with the existing Aluminum coupler. I think there is a chance of misalignment. 
Would be exploring springs suggested by Maharana as coupler.

Use of Antenna tubes of Transmitters may be quite suitable to fix 2 mm / 3 mm shafts with a 4 mm U-Joint. You get a bunch of tubes with diff. dia by splitting an antenna. Don’t spoil a new transmitter’s Antenna, collect one from TV/Radio repairing shop cost you around Rs.50/-

Maharana your suggestion for using a nylon tube is apt. I tried using a thick cable wire outer sheath as a coupler and it is working fine.The problem of vibrations and misalignment are all taken care off.  :thumbsup:
I cut the inner of a cable wire such that it left enough space for the shaft in the outer sheath at both the ends. Then with the inner piece in place I coupled both the shaft. It works absolutely fine.
I ran the motor for 3-4 minutes at 50% throttle and the motor is not getting hot, neither is there any wear and tear in the coupler. Will give it a longer trial run this weekend.

On no-load these tubes work fine, but how far it can withstand on full load is doubtful. First insert right kind of tube inside a spring to protect the tube as well as a solid grip on driving & driven shaft. See the fig.
  

I am back after a long break of 2 month. But first the good news... I have been blessed with a baby girl on 27th August.Fatherhood has been keeping me busy. Got to sneak a few hours to progress on this project.
Close to completion.

Maharana thanks a lot for your suggestions on the coupler. :salute: :bow:
I have made it exactly as per your recommendations.. .It is amazingly stable and takes care of the slight misalignment of the shaft and motor.

I completed the rudder assembly  and the electronics placement in the boat. Also glued the top covers of the boat. Struggled a lot with making a cooling coil for the motor with a SS pipe.Just couldnt bend it to size. Finally have decided to make the cooling coil from copper pipe. Will install the same by tomorrow. Intend to glass the boat as the next step. I think will be able to complete the same the next week end.
Here are some pics of the coupler and the boat.

some pics of boat

This looks great!!!!

hope u will get some time to finally complete this!!!!
cheers
Ashish

Finally completed the cooling for the motor. Used a copper 4mm pipe for this .Crimped one end. filled up the complete pipe with table salt. Used a paper cone to fill up the salt.once filled crimped the other end of the pipe as well. Since the pipe was very malleable could easily turn it on the motor. In case the pipe is not very malleable then it has to be turned on a bar with dia equal to that of the motor. Managed to make this coil after one failed attempt to make this coil out of steel pipe.
 Also installed the water pickup. As of now the water pickup is placed between the transom and the prop.
planning to shift it to behind the prop. water outlet is on the left side of the boat.

 here are some pics.

Managed to fibreglass the boat this Diwali vacation. Also completed the top covers of the boat.
Fibreglassed with 50:1:0.1 ratio of Resin: hardener:cobalt. Too much of caution proved otherwise for me. I feared the resin might harden up too fast and reduced the hardener.It took a  longer time to cure. Some part took almost a day.
First cut the fibre cloth to size. It can be easily be cut by hand. But gloves are a must.The  resin is too sticky to come. Although not as bad as a feviquick.
Glassed one part at a time and prepared the resin mixture accordingly.Cloth is to be put in place with spots of resin and then using a paint brush to apply resin mixture all over. Then moved on to other parts. Repeated this with another layer of cloth.
Would now be sanding this and then painting and making the canopy.
Should be able to sail in two weeks.

Instead of a underwater propeller, can we use a propeller above the water to push the boat. and this pusher propeller can be steered with a servo. Don't you think that would be a cheaper and a easy option.

hey frnd,
where did u get prop, shaft, radar and all...
pl respond soon....
i am also making a boat u can see in my recent post...

As for the prop. I got the same for India Hobby centre Mumbai. Since you are in Bangalore.. you can also try Rcforall . there are good props available there as well. I made the shaft and the stuffing tube myself at a local workshop.The shaft is a steel rod of 4mm dia. Threaded M4 threads at both ends. also got a tube to suit this.
A better option to the shaft is a cycle spoke. It is also 4 mm and has thread at one end with a nut.I did not use this since the length didn't suit me. What is the motor that you are using. I see you already have a prop.Do you want to change the prop.
The rudder is again made from scrap metal plates from a PC. The rudder guide is made from a broken stapler. a closer look , will give you the idea.

Thanks a lot...
i have a outrun brushless motor! it high torque motor....
ya i bot prop and a u joint from RCFORALL thats going good a i have a shaft of 4mm...
all is i have to fix ball bearings to run the shaft properly.
and will that prop half out of water work? and your out radar is really good...
But how did u joint that shaft and prop i din get u!

Why are you using ball bearing and where are you installing it?
I have made a drive dog.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXMWA7&P=0
This drive dog slips over the shaft. I glued it to the shaft with epoxy and prop slides on the shaft and locks itself on the dog the other side you then tighten it with nut.Check out the water pick up picture on the 32nd post on this thread, should give you a clear idea.

Finally managed to complete and sail it yesterday. Following were the outcome of the maiden sail.
It seems to loose power since the nose dived with higher throttle... Reason: seems that the prop is thrusting the motor than the stuffing tube. Would be rectifying the same with a spacer between the prop and the stuffing tube.
Cooling seems to be OK. As suggested by maharana would be changing the water outlet from the side to the back inside water. This would ensure that air does not enter the cooling channel.
Also would be adding cooling for ESC. It seems to get hot.

Would post video of the same with the above changes.

it looks great!!!!!!! congrats after so many efforts and time, u were able to maiden it!!!!!!!!

cheers

Sreekant sir,
Looking good..At last you are done with it....

looking forward to your video.....

hey nice!!
great job on the prop n rudder...i've made the same boat too :) :) :)
how have you coupled the motor and propellor shaft???i always have a hard time with the coupler :banghead:
if only i had seen this thread earlier...

Just a thought.

Since the boat is 'nose diving' at higher speeds, could it be possible that your horizontal stab is generating a lift at the aft (tail)? That would result in the bow (nose) being pushed below the water line. The higher the speed, the more lift would be created at the tail.

What do the experts feel?

hi mate.
nose diving..........place the battery behind the half way of the hull.
water cooling...this 'should not' be necessary with the brush less motor especially 'with a heat sink on'.
looks good though and nice and cheap build  ;)
a video of this would be nice :-)

regards
don

Thanks guys for your views.I changed the battery position on my second run and the nose diving problem is solved. Now is the craving for more speed hence I am now admist clanging the motor to a 3050kv brushless and a 5000mah battery and a 42mm prop.
Guess this should make it faster.  Just that no one to take videos of my runs :banghead:
But would be asking ashish to help me with the videos. Will post shortly.

I have used a Spring as a coupler. To connect it with the drive shaft I have inserted a Cycle spoke nut into one side. And on the other side is a M4 screw. I am using a EDF motor and it has a M4 tap at the centre. Hence this M4 screw from the coupler spring directly gets screw onto it. will post closer pics of the same.

hi mate,
glad it's sorted  :)
good luck with the new motor fitting.
look forward to video  ;)
regards
don

good boat

Was not too happy with the fixed shaft drive. Hence decided to change it to a flex shaft drive. My second attempt at using a flex drive. Ensured correct machining of the components to avoid all the mistakes done the first time. Found that the coupler machined the first time had a lot of deviations. Used a speedometer wire for the flex shaft. The direction of windings on the flex shaft make apt for a counterclockwise rotation.  Will be  also changing the motor to a 3060kv water cooled motor with a 3S 5000 mah Lipo. Have also upgraded the ESC to a Hobbyking SS 70 amp water cooled ESC.
Got the Strut shaft and the strut holder all machined in SS hence would take care of the corrosion. The Coupler is made of hex brass . Would be now driving a 42 prop on this , from the previous 32 prop.

Drive dog is pending to be machined.  Will post detailed photos of the shaft in some here. Here is the partial assembly.

hi mate.
looks good........ how's it coming along with the machining?
this should add some serious power........
regards
don

This probably is the longest build on this forum.Have been completing this with baby steps.
Have finally managed to change the drive to a flexible drive. changed the coupler to a brass coupler. Got the same machined from a local workshop. Have managed to minimise the inefficiencies to a large extent such as the Teflon washer behind the drive dog.
Will be running this on a 3s 5000mah lipo.
Here are the pics.

Some more Pics

Ready to Sail.

The maiden went smooth .. could not record it.
The second run was a eye opener to me .. Missed out on two important aspects
1) checking the range of the Tx. Mine was running with old alkaline batteries and the did not take care of the range. Big mistake.
2) Did not tape down the cannopy. assumed that the magnets will take care of it.
result the boat went out of range and braked suddenly with a nose dive and the cannopy thrown off. water entered the boat.. Luckily all electronic safe.since had everything in balloons. Will sail it again this week end. The speed with just 10% throttle was awesome. Sprays water at the back as every boat lover would like to see.

http://www.youtube.com/watch?v=UI3adABCU_g&feature=youtu.be

Shreekant

Finally.......great going!!!!!!

Monster! You will need a MUCH bigger pool for this baby. {:)} {:)} {:)} {:)} {:)}

Thanks VC!
It surely needs a larger pool... Infact I was not allowed to run in this in our society pool the first time for its size. the attendant was scared if this thing does some damage to the pool.

Waiting for the weekend to take this to a lake.

Shreekant

 :giggle: :rofl:

well done Sreekant,
Flexy shaft seems very suitable and generating goo speed also. would love to see on a bigger surface.
 :thumbsup:

Excellent job Sree..actually was waiting to watch your video..because of slow connection it was in list..congrats for your great efforts..as mentioned, waiting to see her on a big water source.. :hatsoff:

A  couple of Requests
.
1. To Some of the experienced boat modellers: How about an "INTRODUCTION to MODEL BOATING" section. along with' HOW TO DO IT TIPS' with input and tips as well as links.

2.  to Roooster: A detailed description of the FIBREGLASSING technique with links.

P.S the advertising board is called foam board at Chennai. about the weight and strengh of plywood of same thickness. Cuts with a hobby knife and sticks very well with cyano. available in thicknesses from2 to 5mm.(this is what I have used other thicknesses may be available.) Good stuff to mount a motor on a small foam.
regards
Avijit

Next boat to be a Fibreglass moulded hull. Will be including detailed fiberglass build pics for the same.

Shreekant

Please start the work on it, as early as possible..great.. :thumbsup: :hatsoff:

shreekant,

hats of to you sir for this patient build,
it indeed is a very long build but he result has paid off every pains int he making process,,
the boat is really awesome will contact you soon as i want to build 1 for my self.
sent pm

Got some time to experiment on the stability of my Atlas Van lines. Here is the video of the boat without the turn fin. Almost line boat on Steroids…. Many of the turns that you see are not intentional but just due to the lack of stability in absence of the turn fin.And this is only at less than 50% throttle.

http://www.youtube.com/watch?v=6YfC7LFOQkc

Added a turn fin to the right sponson... Although brought in stability to some extent... But now I realise that I have installed the rudder on the same side as the turn fin...This does not give the boat the stability on both the sides of the boat Hence the turns.
will be changing the rudder to the other side.

thanks to RCNeil21 for the video taken last weekend. Thanks Neil.
Here is the video with the Turn Fin

http://www.youtube.com/watch?v=VelQkWLC84M

Here is the rudder placement Will be shifting it to the other side.

1st video- you are taking a lot of sharp turns(not required) its only slowing/breaking the speed.

In the 2nd video boat is very stable and fast.
excellent job {:)} {:)} {:)}

Wow the difference between the first video and the second one is quite a bit like Sb sir pointed out.
Changing the rudder position will stabilise it a lot more right sir?

@maharana: many of the turns in the first video are without any rudder movement. . The boat just turned when throttle was increased. This was taken care with the turn fin to some extent... but again since the rudder and turn fin are on same side of the boat. . The problem remains. . Hence now moving the rudder to the left of the boat.

Got it, both the rudder and fin will act like guide to the boat.

hey Rooster....good to see it flying ...long time man!!!!! ye to dubki bhi lagati hai!!!! :-)