Model Boat Mayhem

Please login or register.

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

Author Topic: Building the Caldercraft Imara  (Read 20757 times)

Bungie 247

  • Guest
Re: Building the Caldercraft Imara
« Reply #25 on: September 23, 2008, 10:02:16 PM »

@Bosun - Excellent, do you have any pics or video I could view/post? Is there anyway to boost the smoke output? Does it require distilled water or is "furring" not a problem?

I hope your workshop is completed soon  :)
Logged

Colin Bishop

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 10,590
  • Location: SW Surrey, UK
Re: Building the Caldercraft Imara
« Reply #26 on: September 23, 2008, 10:03:51 PM »

You can get a couple of 12v 1.2ah or 2.2 ah sealed lead acid batteries for your 24 volts. They don't weigh all that much and will easily fit in a big tug hull although you may need to charge them separately if you are using standard SLA chargers which normally only go up to 12v.
Logged

Marks Model Bits

  • No Mustang Mark
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 889
  • http://marksmodelbits.com/
    • Marks Model Bits
Re: Building the Caldercraft Imara
« Reply #27 on: September 23, 2008, 10:13:09 PM »

Hi Martin, furring could be a problem if you live in a hard water area but you can use distilled water. The membranes can be replaced easily though and only cost a fiver. there is instructions included on how to increase the airflow through the unit so you can play around with it.

Mark.
Logged
I HAVE NOT FAILED, I HAVE FOUND 1000 WAYS THAT DON'T WORK.!!!!

http://marksmodelbits.com/

Bungie 247

  • Guest
Re: Building the Caldercraft Imara
« Reply #28 on: September 25, 2008, 11:21:51 PM »

Ok, my first small problem. I don't have any propellers in the kit. Not a problem really because I was going to fit brass ones anyway. What concerns me more is that a bag they should be in may be missing. Has anyone any ideas as to what was in the bag with the props (if anything) otherwise I shall get on to Caldercraft.

Martin.
Logged

Bungie 247

  • Guest
Re: Building the Caldercraft Imara
« Reply #29 on: September 26, 2008, 11:24:52 AM »

Hi peeps, I contacted Caldercraft and was informed that the props are no longer supplied, so panic over  {-)
Logged

Tug-Kenny

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 7,671
  • Location: Newport. S Wales
Re: Building the Caldercraft Imara
« Reply #30 on: September 26, 2008, 07:24:36 PM »

Ok, my first small problem. I don't have any propellers in the kit. Not a problem really because I was going to fit brass ones anyway. What concerns me more is that a bag they should be in may be missing. Has anyone any ideas as to what was in the bag with the props (if anything) otherwise I shall get on to Caldercraft.

Martin.


Hi Martin

There are 29 sealed bags in my Imara kit. You are correct, as I do not have any Props either. At least you've cleared this up for me as well.

Cheers

ken
Logged
Despite the high cost of living   .......... It remains popular

Colin Bishop

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 10,590
  • Location: SW Surrey, UK
Re: Building the Caldercraft Imara
« Reply #31 on: September 26, 2008, 07:40:22 PM »

You are not missing anything, they ware quite unsuitable for a working model. Same goes for the clunky rudder too in my view!
Logged

Bungie 247

  • Guest
Re: Building the Caldercraft Imara
« Reply #32 on: September 26, 2008, 07:49:48 PM »

@Ken - Glad to be of service ;) I spoke to Caldercraft, they no longer put the props in the kit because people use different props for Electric & Steam but if you want to build a "Static" Imara they will send the props to you.

Any news on your hull yet?  :-\

@Colin - What don't you like about the rudder Colin?

Regards, Martin.
Logged

Tug-Kenny

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 7,671
  • Location: Newport. S Wales
Re: Building the Caldercraft Imara
« Reply #33 on: September 26, 2008, 07:57:41 PM »

@Ken - Glad to be of service ;)

Any news on your hull yet?  :-\

Regards, Martin.

I have heard from Germany and they have OK'd the replacement. We have yet to arrange delivery dates.

ken
 
Logged
Despite the high cost of living   .......... It remains popular

Tug-Kenny

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 7,671
  • Location: Newport. S Wales
Re: Building the Caldercraft Imara
« Reply #34 on: September 26, 2008, 07:59:15 PM »

You are not missing anything, they ware quite unsuitable for a working model. Same goes for the clunky rudder too in my view!

Hi Colin

I thought that too when I saw it. No doubt I shall be enquiring a better way of doing it when I get around to starting her.  ;)

ken
Logged
Despite the high cost of living   .......... It remains popular

Colin Bishop

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 10,590
  • Location: SW Surrey, UK
Re: Building the Caldercraft Imara
« Reply #35 on: September 26, 2008, 08:20:10 PM »

Quote
What don't you like about the rudder Colin.

On a model of this size the rudder servo is going to have quite a bit of work to do and a rudder consisting of a chunk of white metal melted around a bit of metal rod weighing around 5 oz or about 130grams doesn't make things any easier. I used the kit version as a pattern and made a replacement made of wood fitted to brass tube using tangs for stiffening. (You could use aluminium alloy sheet instead. I also made up a custom lower support bracket with bearing which bolted directly to the keel so that it would be possible to dismantle the rudder assembly for regreasing the tube etc.

The rudder supplied in the kit will work but I found it too crude for my taste.

Colin
Logged

Bungie 247

  • Guest
Re: Building the Caldercraft Imara
« Reply #36 on: September 27, 2008, 01:09:36 PM »

@Colin - I had not realised that. I assumed (assumption being the mother of all foul up's) that the rudder shaft at the point at which the rudder is moulded would have at least have been "keyed" in some way. Thanks for the tip.  :)
Logged

Bungie 247

  • Guest
Re: Building the Caldercraft Imara
« Reply #37 on: October 01, 2008, 04:49:33 AM »

Hi peeps, been a little while but I am here to tax your brains again.  ;D  I wonder if anyone can tell me if the propshafts on the Imara are supposed to be parallel with each other or not. It is not important really, just a healthy thirst for knowledge  :D

Also I also need some suitable props. Preferably four bladed (three bladed would do) with a 2ba fitting. What size do I require and from where would I purchase such a beast?

Anyhow, my latest exploits are at www.imarablog.org as usual.

Regards,  Martin.
Logged

Tug-Kenny

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 7,671
  • Location: Newport. S Wales
Re: Building the Caldercraft Imara
« Reply #38 on: October 10, 2008, 10:10:15 PM »


Hi Martin

Been away on holiday, so have only just caught up with your Blog.

I too, have purchased the four bladed props from Westbourne's, and quite chunky they are as well. A nice bit of kit, as they say.

With regards to your 'lining' the stand, a lot of modellers go for a cut up mouse mat. I did this with one of my stands, but have gone over to Felt from a piano as it's softer and more resilient for heavy models. Nothing worse than scratching a freshly painted hull.

Ken
Logged
Despite the high cost of living   .......... It remains popular

Bungie 247

  • Guest
Re: Building the Caldercraft Imara
« Reply #39 on: October 14, 2008, 12:45:09 PM »

@Kenny - I hope you enjoyed your holiday and have returned well rested. Using a mouse mat for padding is a cool idea. I will try that if my pipe lagging experiment is a failure.

Well my props have now arrived from Westbourne models (thanks peeps) and I now have a question. Does anyone have a suggestion for the prop rotation? I assumed that the props would rotate as follows.

(When viewed from astern of the hull - props running in the ahead direction)

Port prop - Clockwise

Starboard Prop - Anti Clockwise



I have read some articles that suggest that this is correct as well as the wrong way, however this is the method suggested by the plans. What are your thoughts? Does anyone know a definitive answer for the Imara?

Regards, Martin.
Logged

Martin [Admin]

  • Administrator
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 19,721
  • Location: Peterborough, UK
    • Model Boat Mayhem
Re: Building the Caldercraft Imara
« Reply #40 on: October 14, 2008, 01:13:46 PM »

Prop rotation, one of the great Mayhem debates.....

The convention I think is:-
Slow / displacement / scale boats:
Port clockwise  - Starboard Anticlockwise.
(The wash meets in a downward direction giving better rudder control. )

Fast / planing / surface drive:
Port Anticlockwise - Starboard Clockwise.
(The wash meets in a upward direction giving better speed. )

....... I now stand back to be proved wrong a thosand time!  :-)
Logged
"This is my firm opinion, but what do I know?!"    -   Mayhem FaceBook Group!

nhp651

  • Guest
Re: Building the Caldercraft Imara
« Reply #41 on: October 14, 2008, 02:35:05 PM »

According to Nicholson's guide to seamanship, on a twin screw ship, the majority conform to starboard prop....right handed, ie clockwise, and port prop left handed..ie anticlockwise.
hope this helps. neil.
Logged

Bungie 247

  • Guest
Re: Building the Caldercraft Imara
« Reply #42 on: October 14, 2008, 02:58:53 PM »

Shhhh, can you hear the sound of a can opener removing the top on a can of worms somewhere?     ok2

Too late now I guess. The blue touchpaper has been lit.... (Bungie stands back to enjoy the show)       :-)

Seriously, thanks peeps. I think that Martin may have the modelmakers solution and nhp651 the real world one. Now as my Imara is going to be a working and heavily used model, I will try the props in both modes and give you my opinions when tested.
 
Logged

nhp651

  • Guest
Re: Building the Caldercraft Imara
« Reply #43 on: October 14, 2008, 03:06:38 PM »

hi bungie,
I've tried mine in both modes, before......usually when I've made a "mistake" and not fitted them as in the "real world", and to tell you the truth, I don't think it makes a hapeth of difference...well as far as my untrained eye could tell.
I didn't see any different handling charactoristics either way that they were fitted.
I think I just fix them that way for authenticity and to stop some smug ol' b****r in the club telling me that "you've got it all wrong".......you know where I'm coming from. {-) %% :-))
Logged

Bungie 247

  • Guest
Re: Building the Caldercraft Imara
« Reply #44 on: October 14, 2008, 03:14:16 PM »

@nhp651 - Yup, I know that feeling very well. I always hear Harry Enfields "I don't think you really wanted to do that did you?" character in my head on those occasions.  %%
Logged

Colin Bishop

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 10,590
  • Location: SW Surrey, UK
Re: Building the Caldercraft Imara
« Reply #45 on: October 14, 2008, 04:30:19 PM »

My original review model of Imara took a lordly disregard of the rudder altogether. I had to steer her on the props - not the white metal originals of course but nice brass ones. I'd be pragmatic and try them both ways. If one works better than the other stick with that. If there's no difference then fit them in the officially approved way. If somebody complains you've still got it wrong then get them to take a real good close up look with their nose under the stern and give her full throttle. The bottom of the boat should be painted red anyway so you won't notice the mess.  ok2

Colin
Logged

Bryan Young

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 6,894
  • Location: Whitley Bay
Re: Building the Caldercraft Imara
« Reply #46 on: October 14, 2008, 06:46:04 PM »

Not wishing to re-start the "discussion" on L or R handed props. I would only offer this as a consideration. Which side of the ship/boat etc. do you normally berth to the landing stage? If it is "port-side" to the quay then having the props turn outwards makes life easier...transverse thrust does most of the work. Reverse all that if you normally go the other way round. BY.
Logged
Notes from a simple seaman

Colin Bishop

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 10,590
  • Location: SW Surrey, UK
Re: Building the Caldercraft Imara
« Reply #47 on: October 14, 2008, 06:48:58 PM »

The version of Imara being discussed here has twin props Bryan. I assume your comments relate to single screw vessels.
Logged

John W E

  • I see no ships !!
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 8,530
  • Location: South shields
Re: Building the Caldercraft Imara
« Reply #48 on: October 14, 2008, 07:15:34 PM »

Hi there All

Here's some food for thought;

HMS Ajax - 4 props - all turning outboard - with electronic mixer and she spins on a sixpence without a mixer - turns, but in about 3 ships lengths using rudder only.

HMS Ajax - same ship as above - inboard turning props -  makes an ideal straight runner and she refuses to turn - even with Mixer

MTB - triple prop - two outermost props turning outboard; inner prop turning ante-clockwise - no electronic mixer - but with scale rudders - turns in about 20 boat lengths - not very manouvreable

MTB - same boat as above - but reversing the outermost props to turn inboard and it is the most un-manouvreable boat - but, there is a slight increase in speed.

VOSPER 73ft RAF Rescue Launch - twin prop - outboard turning - scale rudders - dont think there is  a lake big enough for her to turn in - with or without mixer or reversing the props to inboard - it makes no difference - she just persists in running in a straight line.

SEAFORTH CLANSMAN - no props and still she goes like stink    hahahha    seriously, two props outboard turning in fixed court nozzles; with an electronic mixer and a bow thruster, obviously when we use the bow thruster and the mixer you can get the model to do anything you like - even the Swan Lake Ballet ??? without using the electronic mixers or the bow thruster she still has a pretty turning circle

I have been told by the 'tuggies' at the Boat club - if you want manouvreability - have outboard turning props - independently controlled.    If you want sheer pulling power, have them inboard but you do lose out on manouvreability.

Last but not least, RAF Whaleback - 3 props turning the same way - with electronic mixer and can control each motor independently - *horrible* useless..................lorra lorra watta arl owa the place and plenty stern shift to one side  :embarrassed: :embarrassed: :embarrassed: :P

Aye
John e
Bluebird



Logged
Pages: 1 [2]   Go Up