Model Boat Mayhem

Please login or register.

Login with username, password and session length.
Pages: 1 [2] 3 4 5   Go Down

Author Topic: Trumpeter Kilo 1/144  (Read 22358 times)

andyn

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #25 on: October 01, 2011, 02:08:22 pm »

Very glad you're satisfied with my work ;)

Andy
Logged

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #26 on: October 07, 2011, 09:03:14 pm »

H
Logged

andyn

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #27 on: October 07, 2011, 09:27:23 pm »

Logged

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #28 on: October 07, 2011, 09:59:07 pm »

Hi All
Think I must be having computer probs having difficulty posting? or its the vodka !!!
Just a bit more progress and my decision to use a single compartment wtc. I was going to have three the middle compartment as a water ballast tank being operated by RCABS with a balloon inside and the surrounding exterior of the compartment drilled with holes. However it seemed to much of a squeeze and more. So I have changed from air to a reversable water pump and a single wtc. I had the water pump and have purchased a reverse switch from Sub-tec.
It may be of interest to a few that a webs site www.swallowdental.co.uk sell online saline bags 250mg,500mg and 1000mg I will keep you informed if they sell one or two offs!!!

Regards
Ian  :-))







Logged

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #29 on: October 15, 2011, 08:48:01 pm »

More progress with sorting the wtc .
I used MMB seals for the servo shafts cutting them shorter to fit my requirements The motor seals were also supplied by MMB
as the end caps, I modified the outlet/inlet of the water pump to get it in the cylinder and it fits nicely on the end cap 
I have done a "float test" and with all the gagetry inside the wtc, the battery stored in the bow and with 2ozs of lead in the bottom the sub sat very well in the water. Still waiting for my water bag/ balloon and trust it will submerge the sub when filled . I am still contenplating making a cylinder to fit inside but it would need an air valve and a tube indside to take the wiring  to and fro so I think I will go ahead as planned.  The cost so far being minimal as I had a lot of the parts !!!
Will keep you posted
Ian  :-))







Logged

Subculture

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 4,005
  • Location: North London
    • Dive-in to Model submarines
Re: Trumpeter Kilo 1/144
« Reply #30 on: October 15, 2011, 09:09:13 pm »

Just a word about the water pump you're using. I tried a couple of these pumps out, and they pump very well (good volume and pressure), unfortunately the material used for the gears is rather soft, and as a consequence these pumps do not like to be run dry for even a short length of time. If you do, you will find the gear driven off the motor looses its 'key' and the pump fails. If this pump had brass or composite gears, it would be a superb little unit- pity.

I would recommend running this pump at a lowish speed say 3-4.8 volts, that way if the pump does run dry, the RPM is lower and this should hopefully avoid the above scenario. It should still be pump quick enough or the size of tank needed for a 1/144th kilo!

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #31 on: October 15, 2011, 09:46:33 pm »

Oppps
Thank you for that info rather worrying I must admit it did rev and pump very fast !!  as a contingency I could try cyno or thread lock the gear to the shaft as well as drop the voltage.
Not being that "electrical technical" can you advise me if and how I  drop the voltage just to the pump from the 7.2 battery supply
rather than fit two batteries
Thanks

Ian  :-))
Logged

Subculture

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 4,005
  • Location: North London
    • Dive-in to Model submarines
Re: Trumpeter Kilo 1/144
« Reply #32 on: October 16, 2011, 12:58:04 pm »

I very much doubt that any glue will last long to be honest, especially cyano. The gear is a push fit onto a d-shaped shaft. Pinning the gear would work, but you would need to be very accurate as the shaft is small, plus you will introduce a possible failure point as it will weaken the shaft at that point. But i think you will be okay providing you run the pump slower.

To run the pump on a lower voltage on the same pack, you could connect a splitting lead into the pack so that you only run the pump on say three or four cells (3.6-4.8 volts). Not the best practice, as those batteries will flatten out before the others, but it's the simplest solution I can think of.

The other alternative would be to get one of the 'orange' geared pumps, which are about a fiver off ebay. They're designed for 12 volt operation, but will work okay at a lower voltage. I'm not sure if you have room for that pump in a tiny boat like that though.

http://www.ebay.co.uk/itm/BN-Universal-12V-Lucas-Type-Windscreen-Washer-Pump-/360390328712?_trksid=p4340.m263&_trkparms=algo%3DDLSL%252BSIC%26its%3DI%26itu%3DUCI%252BIA%252BUA%252BIEW%252BFICS%252BUFI%252BDDSIC%26otn%3D8%26pmod%3D250735261541%252B250735261541%26po%3D%26ps%3D63%26clkid%3D2513906338043357330

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #33 on: October 26, 2011, 11:13:10 pm »

Well after some thought I have decided to go with what I have and trust that  in such a small sub use "should" be minimal. There is no way a separate supply can be used and any idea's of dropping the voltage using resistors I dint think possible / practical ?
I am now waiting for a rubber ballast bag from Hong Kong ( cheaper than USA ) I did try to buy a sterile bag from Swallow an on-line dental supplier but was informed by them and the manufacturer very definitely that it was illegal to sell them unless you were a registered practitioner and they needed my practitioners number etc. so no help there. What can be illegal about an empty bag !!!!!!!(probably an EU law )  I think it will be a bit of a challenge to place it all in the one wtc compartment like a ship in a bottle !!!
Cheers
Ian  :-))
Logged

andyn

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #34 on: October 26, 2011, 11:29:34 pm »

To drop voltage down, use an ACTion P19

http://www.action-electronics.co.uk/pdfs/P19.pdf

Andy :-)
Logged

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #35 on: October 27, 2011, 12:25:38 am »

Hi Andy
Many thanks for that but do I understand that the P19 will drop the voltage for all the components not just the pump.  5 volts may not drive the prop motor to well  and to far down the road to change the motor. I have tried running it all on a  4.8 volt battery and the prop is very slow and the voltage reversing switch does not behave to well . I need to have 4-5 volts after the reversing switch for the pump if poss ?
Regards
Ia :-))n 
Logged

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #36 on: October 27, 2011, 12:36:26 am »

Hi Andy
On thinking about it I assume I could use this P19 after the reversing switch just for the pump to give it 5 volt ?
Its late  :-))
Logged

andyn

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #37 on: October 27, 2011, 11:02:43 am »

Ok then, so basically what voltage do you need for different areas?

From what I can tell, you need 6-12 for the motor and 5v for the pump and radio, so why not use an Esc without a bec, and run the pump and radio off the P19?

Andy :-)
Logged

Subculture

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 4,005
  • Location: North London
    • Dive-in to Model submarines
Re: Trumpeter Kilo 1/144
« Reply #38 on: October 27, 2011, 11:21:49 am »

Running a pump and radio off a 1A (peak) linear regulator? :o

You could use a switching BEC, and I'd recommend a heavy duty one at that, at least 5A rating.

e.g. http://hobbyking.com/hobbyking/store/%5F%5F10313%5F%5FTurnigy%5F5A%5F8%5F40v%5FSBEC%5Ffor%5FLipo%5F.html

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #39 on: October 27, 2011, 05:36:52 pm »

Thank you gentlemen for you thoughts and advice. i
Logged

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #40 on: October 27, 2011, 05:55:43 pm »

Another blip!!

I emailed Action-electronics and they did not recommend their P19 but offered me alternatives. I think using the Turnigy with the 5 amp
rating should do the trick and they are very reasonably priced I trust the dimensions are small enough ? the weight certainly is.
Ian  :-)) 
Logged

Subculture

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 4,005
  • Location: North London
    • Dive-in to Model submarines
Re: Trumpeter Kilo 1/144
« Reply #41 on: October 28, 2011, 11:19:35 am »

They're very compact, as they're switch-mode based as opposed to linear regulation. Just position it as far away from the receiver as you can.

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #42 on: November 04, 2011, 09:51:38 pm »

Hi
On the advice given have purchased the switching bec and now have the pump running on 5 volt. It was a little larger than hoped which meant a few mods the pump end of the wtc. Everything was running fine out of the wtc .However after having stowed everything in the wtc complete with balloon to test I had problems with the the reversing switch which decided not to reverse. This could be my fault if I unwittingly got the polarity mixed for a nanosecond !! I am now waiting for the switch to be checked out which has put a stop to any more progress here.
I have however completed a few "sink" tests to see how the sub floats in the water and with everything on "board" the battery in the bow and three and a half ozs of lead weight distributed under the wtc the sub is looking ok. Obviously a lot more testing to do when the pump is working and poss more weight to get it to submerge ok !
Ian :-))
         



Logged

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #43 on: November 09, 2011, 12:35:52 am »

Hi
Still waiting for the return of the reversing switch for the water pump motor but thought I would try a  trial with the balloon filled with water inside the wtc and all the "kit" and see if it submerged ok !!. With a 100 grams of water in the balloon it did the trick and would probably take less but have proved the point that it sits on the water ok and submerges.!!
Ian  :-))



Logged

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #44 on: December 11, 2011, 04:47:05 pm »

Hi all
Well the last pictures showing trials in the "sink" looked ok but these were done by just manually filling the balloon and joining the wtc .
However quite a different matter when its all connected and using the water pump by RC to do the job. I have had real problems and still not convinced I have it sorted. The pump being a gear pump leaks ie back flow and to fit a solenoid valve to control this there is not the room plus I have a big enough problem with air pressure in the wtc already which adds to the problem of forcing the water out of the balloon.I have tried  to get a small vacuum in the wtc by part filling the balloon with water joining the wtc and empty it which I suppose could suck the water back in through the pump !!!. However I attempted some "sink trials to see what happened and the result was it worked but probably by luck and not judgement !!. By the way the balloon is quite large so it is not under a lot of internal pressure when the water is in it.
But I am sure some of you guys have a better answer any help appreciated . A different pump would seem the answer with no backflow but I cant find one and it must be small enough as the wtc is 45mm inside diameter. Or maybe back to the drawing board with a different system !!!

Ian  :-))
Logged

Subculture

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 4,005
  • Location: North London
    • Dive-in to Model submarines
Re: Trumpeter Kilo 1/144
« Reply #45 on: December 11, 2011, 08:30:42 pm »

I find  a pinch valve works better than a solenoid valve, because the latter are usually designed for flowing air/gas not water, and thus tend to have small valve sizes and can corrode.

I made a small pinch valve for a geared pump system using a miniature 9 gram servo which works great. Easy to make and very small, but you may have problems finding room in that little module.

Peristaltic pumps are self sealing. This chap sells some, can't vouch for quality I'm afraid, and he seems to have put up his prices a bit recently, but I haven't seen smaller peristaltic pumps readily available elsewhere. Ideally you should also include a pressure switch or some sort of mechanical bypass for this system. Pumping rate is slow compared to a geared pump.

http://www.ebay.co.uk/itm/RC-Submarine-Micro-Rolling-Pump-Type-B-DC-4v-12v-/280771359797?pt=Radio_Control_Vehicles&hash=item415f46f435

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #46 on: December 11, 2011, 09:13:17 pm »

Many thanks for your reply.
I have  viewed the pump you mention a few times but by the measurements quoted it will not fit in my 45mm diameter wtc. The pinch valve is an idea and although room is a problem it is easy enough to make and I have a 9gram servo and definitely worth a try. Thank you for the suggestion
Ian  :-)) 
Logged

Subculture

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 4,005
  • Location: North London
    • Dive-in to Model submarines
Re: Trumpeter Kilo 1/144
« Reply #47 on: December 11, 2011, 09:18:59 pm »

I use the thinner walled silicone tubing, as it's easier to pinch off. I reckon a 5 gram servo would be man enough for the job, as it requires very little effort to pinch the hose up.

I made mine up out of some thin sheet copper, but there are various ways of doing it.

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #48 on: December 11, 2011, 11:26:52 pm »

Thanks again
I have just found a 5 gram servo amongst my bits and pieces so will get to and will post the results later
ian  :-))
Logged

coolbumble

  • Guest
Re: Trumpeter Kilo 1/144
« Reply #49 on: December 13, 2011, 10:34:32 pm »

Hi
Out of interest I see a pump similar to the one I am using in the kilo is advertised from China (okey 100c) on ebay with a DIY steel gear and inlet/outlet conversion working at a lower voltage .

A pity it was not advertised earlier may have saved me a few problems however at the reasonable price I though it worth a buy.

Ian   :-))
Logged
Pages: 1 [2] 3 4 5   Go Up