Model Boat Mayhem

Dry Dock / Shipyard: Builds & Questions => Navy - Military - Battleships: => Topic started by: tobyker on June 24, 2008, 06:11:02 PM

Title: Chinese 20 warships
Post by: tobyker on June 24, 2008, 06:11:02 PM
Has anyone tried to do a "seaport workboat" type make-over on one of those cheap chinese carriers or destroyers? I admit the chrome gun turrets and radar scanners do rather put one off.
Title: Re: Chinese 20 warships
Post by: Martin [Admin] on June 24, 2008, 06:57:40 PM
I saw one at a show, it didn't look too bad painted up properly!
Title: Re: Chinese 20 warships
Post by: tobyker on June 25, 2008, 05:22:22 PM
Thanks, Martin - I'm going down the M40 tomorrow so I might pop in to Kidlington for a shufti and possibly take a punt. I might as well get one anyway - if it looks as though installing rudders and a proper radio won't be worth it, I can always lob it in the direction of a deserving small boy. And if it is worth doing, I'll let everyone know how I get on.
Title: Re: Chinese 20 warships
Post by: Edward Pinniger on June 25, 2008, 05:52:38 PM
I have a "Smasher" (Soviet Sovremenny destroyer) which I plan to do a make-over on soon, with a complete repaint and extra detail (including railings).

Despite its plasticy toylike appearance out of the box, it's actually quite an accurate + detailed representation of its subject, as it's based on the Trumpeter plastic kit (I'm not sure if it's a knock-off of the kit, or if it's actually produced by Trumpeter - I know they have a subsidiary company who produces R/C tanks based on their kits). The "Challenger" aircraft carrier is a Soviet Kiev-class and could also be rebuilt into a good model, though the smaller scale of 1/350 has put me off this one.

I'm fairly certain the model at the Leamington show posted by Martin is actually an original Trumpeter kit, but it does show what the RTR boat could look like with a decent paint job + a bit of cleanup/detailing work!

One tip, if you're not planning on replacing the radio gear + adding rudders, you can get the model to run at a much more "scale" speed by either changing the battery for a lower voltage one and/or replacing the racing-type props with smaller, conventional ones.
Title: Re: Chinese 20 warships
Post by: Shipmate60 on June 25, 2008, 10:39:55 PM
Have you had her apart yet.
I have taken 1 to bits but decided to give the carcass to a friends child.

Bob
Title: Re: Chinese 20 warships
Post by: J.beazley on June 25, 2008, 10:57:49 PM
Anything that could break off it has been broken off it by my son aswell cheers Bob O0

still got to give it to the little toy it still floats in the bath even with half the superstructure missing.

Jay
Title: Re: Chinese 20 warships
Post by: tobyker on June 25, 2008, 11:20:21 PM
Shipmate 60, why did you decide to bin it?
Title: Re: Chinese 20 warships
Post by: Shipmate60 on June 25, 2008, 11:31:16 PM
Firstly, have you got the thing apart yet.
There are screws under the ships boats and to get the foredeck off you need to break off the port and stbd missile launchers.
The one I took apart had the main deck, which continues under the foredeck sealed with silicone, so the hull was split getting it all out.
Nothing drastic, it could have been repaired and I did have another complete one still in the box.
The shaft exits from the hull were distorted and melted (on both models).
When I weighed it all up after she was stripped down it would have been easy to fit "propper" Radio Gear in her, but to me whatever was done to it, it would still be a 15 toy.
As she was sealed so well she would take heavy weather, but again to me she would always be a toy, so just couldn't be bothered while I have so many awaiting building.

Oh yes and it was the hull Martin gave to RMAS Master at Wicksteed, so I just gave him the complete one for his nephew.

Bob
Title: Re: Chinese 20 warships
Post by: Tom@Crewe on June 26, 2008, 02:02:45 PM
are there any pictures of the range available
Title: Re: Chinese 20 warships
Post by: DickyD on June 26, 2008, 02:14:57 PM
Howes Models Tom   http://www.howesmodels.co.uk/RadioControl/viewProducts.php?SubCatID=114
Title: Re: Chinese 20 warships
Post by: herrmill on June 27, 2008, 03:53:21 AM
There's a gent in Bahrain who is in the midst of doing a major conversion on the cheap Sov toy model.

You can follow his build over at RCU: http://www.rcuniverse.com/forum/m_7270463/tm.htm (http://www.rcuniverse.com/forum/m_7270463/tm.htm)

Chuck
Title: Re: Chinese 20 warships
Post by: Edward Pinniger on June 29, 2008, 06:59:09 PM
There's a gent in Bahrain who is in the midst of doing a major conversion on the cheap Sov toy model.

Looks very good! This is more or less what I hope mine will look like when finished, though I'll also be adding rails + ladders.
I might also use the tip of using small magnets to hold the removable superstructure parts in place!
Title: Re: Chinese 20 warships
Post by: tobyker on June 29, 2008, 11:51:09 PM
Cunning plan foiled by rainstorms and accidents on M6. Didn't get to M40 until 5pm - closing time. Rats! May have to pay postage to acquire one shock horror.
Title: Re: Chinese 20 warships
Post by: Shipmate60 on June 30, 2008, 12:01:59 AM
Still looks like a toy to me.

http://cgi.ebay.co.uk/Radio-Control-Sovremny-Model-Boat-Ready-to-run_W0QQitemZ190233378467QQcmdZViewItem?hash=item190233378467&_trkparms=72%3A12|39%3A1|65%3A12&_trksid=p3911.c0.m14

Bob
Title: Re: Chinese 20 warships
Post by: tobyker on July 01, 2008, 01:02:22 PM
Destroyer arrived this am 26 hours from order- well done Howes!. It looks and feels better than I expected. Minor points are moulding flash left on quite a lot of bits, and stickers here and there. I shall take some photos "as delivered", conduct sea trials and then investigate access and potential for modification. The big problem will probably be weight if I decide to add rudders and speed controllers but we shall see. Incidentally the propellors have slotted hubs and fit onto dogs on brass collars fixed to the shafts, held on by Nyloc nuts.
Title: Re: Chinese 20 warships
Post by: Martin [Admin] on July 01, 2008, 01:25:22 PM

...this is going to be a interesting build!   :)
Title: Re: Chinese £20 warships
Post by: tobyker on July 01, 2008, 10:54:54 PM
Thanks Martin. As in the famous Chinese curse "May you live in interesting times". Much quoted in the Civil Service. Don't hold your breath though - I've got a barge to get sailing.
Title: Re: Chinese 20 warships
Post by: tobyker on July 02, 2008, 03:04:40 PM
Further investigation today. I suspect the guy who assembled it was on piece work as there are some minor bits missing off the bridge, and there are two holes under the breakwater in the foredeck for screws which are not fitted. There are quite a lot of sprue marks which need removing. The stabilisers have reinforcing gussets which hang out in the water flow, and the shaft exits are extremely unstreamlined.  The two main turrets and the helicopter flap about and need securing propery - the latter though looks a bit out of scale and may be sacrificed to save weight.The aft deck has large "jelly" bungs  over the screw holes.The boat weighs 1,395g, Bow 675 and stern 733, so I can get the balance right after modification. (I know they don't add up but so long as I support it in the same places the proportions will be right.) Since the battery only weighs 114g, either the motors are very heavy or there may, with luck, be some ballast which can be reduced to compensate for any additions. Some of the superstructure, for example the silver deck on the switch cover, is held together with steel screws, so there is a weight saving high up when they are replaced with glue.  I have done a full "field strip" - switch cover and battery housing, and will delve further after sea trials, which are now unlikely to take place until next week. It may well be that this further investigation will show that it's not worth going any further, but wth. Interestingly, the picture on the box is very true to the model, so it's easy to see which bits are missing. The silver bits are not as glaringly chrome as they look in most pictures, but the dark green missile tubes and boats do look weird. I'm pretty sure that the photo Martin posted was of the Trumpeter kit, as the missiles are showing in the launchers, but on the toy the tubes are closed, and there are no signs of screw holes in the fore deck. I'll try to send photos later, but may have to send them to Martin and see if he can put them in. Now off to try the resizing exercise!
Title: Re: Chinese 20 warships
Post by: tobyker on July 02, 2008, 03:15:49 PM
Pictures maybe.
Title: Re: Chinese 20 warships
Post by: Martin [Admin] on July 02, 2008, 06:39:25 PM

For Reference - Smasher out of the box video:  http://www.youtube.com/watch?v=3itYvp5hhjU (http://www.youtube.com/watch?v=3itYvp5hhjU)

(Ignore all the chatter about the non planing hydroplane! )
Title: Re: Chinese 20 warships
Post by: Shipmate60 on July 02, 2008, 11:03:55 PM
tobyker
There are 2 bits of ballast, they are a shaped cinder ( as in cheap Breeze Blocks )  like material.

Bob
Title: Re: Chinese 20 warships
Post by: tobyker on July 04, 2008, 10:34:14 PM
Thanks, shipmate. Sounds rather like a washing machine then. I'll go looking for them after sea trials. (Hardly necessary now Martin's posted that video, but I need to see it working for a "before and after" comparision). If, of course there is an after!
Title: Re: Chinese 20 warships
Post by: Shipmate60 on July 04, 2008, 10:49:37 PM
There are lots of hidden screws so just take your time.

Bob
Title: Re: Chinese 20 warships
Post by: Edward Pinniger on July 07, 2008, 06:08:42 PM
Regarding the issue with the screws holding the deck, hull + superstructure together, with my rebuild (not yet started) I've decided to basically remove all the screws, fill in the holes and glue everything together, leaving only the superstructure bits over the switch + battery compartment removable (with these I'll either use brass rods or small magnets to hold them in place, instead of the screws). If the motor or receiver go, it'll just have to be relegated to a static display model! But I can't think of any other easy way of dealing with the many large screw holes in the deck and superstructure.

I may have mentioned this before, but one way to give this model (and presumably the others in the "HT" range, like the carrier and Bismarck) a much more scale speed without modifying the running gear is to replace the 7.5v battery pack with a lower voltage; I replaced it with a battery holder containing 4 rechargeable AAs (4.8v total).
Title: Re: Chinese 20 warships
Post by: tobyker on July 08, 2008, 12:00:55 AM
Though I too haven't stripped mine yet, I wondered if after screwing it back together (if I do!), I could fill the screw holes with a short length of slaters plasticard tube topped with a disc which would sit flush with the deck. They could be filled and painted, but couls also be dug out later if required - a photo pre-filling would show you where to look for them. ! Pray for fine weather tomorrow for sea trials of this and the barge. (Has yours got screw hole plugs in the fore deck? mine only had the jelly plugs in the aft deck.)
Presumably a smaller battery pack will give less run time too - I'd be hoping to find space and weight saving to fit speed control. We shall have to do some amp measuring to find out how light we can get that.
Title: Re: Chinese 20 warships
Post by: djrobbo on July 08, 2008, 07:23:50 PM
Hi guys.....got one of these from howes to see what could be done with it..........straight out of the box the radio was crap , but no matter coz i didn't intend to keep it in anyway..........Stripping it all out was interesting , trying to find all the screws was fun , but hey ho onward and upward !
             Came to the conclusion that the best way forward with standard radio gear would be a single prop and standard rudder . It was strangely quite easy to remove all the revolvey leccie bits . i.e motors couplings shafts and tubes etc , and with not a great deal of modification and a suitably placed hole you can reuse one of the origional shafts and tubes and refit it in the centre of the hull and still leave plenty of room for a standard rudder.......haven't done anything since the weekend but will probably get back into it this weekend............we shall see how it all goes back in  :D O0

                 regards....bob.
Title: Re: Chinese 20 warships
Post by: tobyker on July 08, 2008, 10:33:44 PM
It looks like we might have a little fleet of these. My destroyer sea trials today were unsuccessful as it didn't work at all, but maybe it was a bad battery connection as when I got it home and tested eveything, and put it on charge (again) for half an hour, it started working. I made up a charging lead to fit the Pro-peak and now I know the battery is fully charged, so we'll try again tomorrow. I can't wait to start stripping it but do want to see it running first. (The barge trials were a great success - now to rig it). How about some photos, Bob?
Title: Re: Chinese 20 warships
Post by: Martin [Admin] on July 09, 2008, 12:23:32 AM
One starting cheap on ebay....

http://cgi.ebay.co.uk/Remote-Control-3Ch-R-C-RC-Boat-Cruiser-Destroyer-escort_W0QQitemZ120281083622QQihZ002QQcategoryZ2564QQssPageNameZWDVWQQrdZ1QQcmdZViewItem (http://cgi.ebay.co.uk/Remote-Control-3Ch-R-C-RC-Boat-Cruiser-Destroyer-escort_W0QQitemZ120281083622QQihZ002QQcategoryZ2564QQssPageNameZWDVWQQrdZ1QQcmdZViewItem)
Title: Re: Chinese 20 warships
Post by: DavieTait on July 09, 2008, 12:41:37 AM
Looks like they put the superstructure on back to front though , should be 2 main turrets fore end and one aft end not the other way around !!!!!
Title: Re: Chinese 20 warships
Post by: Martin [Admin] on July 09, 2008, 09:19:00 AM
Maybe it's for navies that are not very confident...... 
Title: Re: Chinese 20 warships
Post by: Edward Pinniger on July 09, 2008, 02:56:27 PM
This one (unlike the other boats in the range) is a complete freelance/fantasy design, it seems to be loosely based on the US Iowa-class (Missouri etc.) but re-uses a lot of parts from the "Challenger" Kiev-class carrier, including the Ka27 helicopter! The scale is more like 1/350, not 1/250 as the description says.
Title: Re: Chinese 20 warships
Post by: Edward Pinniger on July 09, 2008, 03:06:33 PM
This one (unlike the other boats in the range) is a complete freelance/fantasy design, it seems to be loosely based on the US Iowa-class (Missouri etc.) but re-uses a lot of parts from the "Challenger" Kiev-class carrier, including the Ka27 helicopter! The scale is more like 1/350, not 1/250 as the description says.

If anyone's interested, I've added a "review" of the Bismarck (http://www.modelboatmayhem.co.uk/forum/index.php?topic=11574.0) to the "What's in the box" section.
Title: Re: Chinese 20 warships
Post by: tobyker on July 09, 2008, 04:56:06 PM
Sea trials (in the sea) completed. Only way to get a decent turn is full fwd on one screw and full astern on t'other, Seems fairly seaworthy though.Couldn't do it at Largs as the lake was full of proper model boats with proper radios. Picture of superstructure and foredeck removed. Lots of the superstructure levels are held together with screws - scope for weight saving there if necessary. Interestingly, several of the jelly bungs seem to have reacted with the dark grey deck, softening it locally. To get this far you have to remove the missile tubes (I hot-knifed the legs) and the motor boats(brute force) The fore turret is not screwed, but sprung onto clips, off which it can be sprung by a a pair of screwdivers. The plastic does not seem to react to polysterene cement, so I think it'll be a superglue rebuild of the loose bits. Next to get the main deck off. Several of the screw holes seem to have hot glue inside.
Title: Re: Chinese 20 warships
Post by: tobyker on July 09, 2008, 06:19:17 PM
Phew! Lots of careful levering with small screwdrivers, and the main deck off. Especially difficult where the chinese superglue has run off the liferafts on to the hull/deck join. I dunno how to get the words in among the pictures but you should see under the deck - the switch and charging pcb, the battery box and the radio box. In the hull are - a cylindrical steel weight, the cinder block weight under the black plastic cover, and the motors with another steel weight between them. aft of them, the white block is a piece of expanded polystyrene in a compartment vented to the sea, outside the sealed hull/deck assembly. Odd. All will now go quiet for a long time while I work out how and what to put together!
Title: Re: Chinese 20 warships
Post by: tobyker on July 12, 2008, 07:48:57 PM
Just checked out the prop shafts - a brass collar with dogs is screwed on to the shaft, then the prop which is slotted to take the dogs, then a brass flat washer, a steel spring washer and finally a Nyloc (type) nut. Both shafts RH thread. Shaft 2.79mm dia, nut 5.41mm a/f. FLJ whom I have consulted about motor controls has advised me to ask SHG about more suitable props. However all is on hold until I've done an amp draw test on the present set-up, which may now be after my holiday. Incidentally, when I opened up the very well sealed radio box under the deck, I found a sachet of silica gel crystals inside. Somebody must have checked Mr Piece-work on that! I am thinking I will open up the deck over the radio box so I can get the new gear in, and build up a coffer dam inside the rear superstructure to stop the water getting in. This will give me access without having to strip the whole deck off. However the steering servo will probably have to sit behind, and be braced to, the shaft supports so that will be less accessible. Lots to think about while I'm away! Meanwhile, all suggestions welcome.
Title: Re: Chinese 20 warships
Post by: Martin [Admin] on July 12, 2008, 09:53:50 PM

 How about wiring the 2 motors in parallel and using a long rudder, or a small rudder with a perspex enlarger?
Title: Re: Chinese 20 warships
Post by: herrmill on July 12, 2008, 11:23:53 PM
Not sure why but I'm now getting spam in my mailbox on this toy.  Is someone else in China watching?  ;)

http://www.globalsourcesdirect.com/servlet/Detail?no=4533&utm_campaign=GSDPRST20080712&utm_medium=eDM&utm_source=eDM_action&utm_content=SKU_SU-07000036-71960&dmsource=GSDPRST20080712 (http://www.globalsourcesdirect.com/servlet/Detail?no=4533&utm_campaign=GSDPRST20080712&utm_medium=eDM&utm_source=eDM_action&utm_content=SKU_SU-07000036-71960&dmsource=GSDPRST20080712)

Chuck
Title: Re: Chinese 20 warships
Post by: tobyker on July 13, 2008, 01:54:20 AM
One rudder? (As in "a handbag?") Get thee behind me Martin - the whole point is to work out how to do it elegantly, not easily.  If I can do it I want twin rudders and a mixer. Per ardua ad (dis)astra, or something. (Though I've never walked sideways, myself.)
Title: Re: Chinese 20 warships
Post by: Edward Pinniger on July 16, 2008, 02:00:35 PM
I've started work on mine a few days ago (or rather resumed work... I repainted the hull and took off all the fittings + small bits last autumn, but it's sat on the shelf gathering dust ever since) - I'll post some more photos in a day or so. The hull, decks + superstructure are all repainted now, so it's looking much better already!
Title: Re: Chinese 20 warships
Post by: tobyker on August 05, 2008, 09:28:47 PM
At last some activity on this one. I thought I'd better measure the wriggly amps so I can work out what to ask my electrical advisor and ESC supplier for. At the first try both motors wired in parallel were pulling 810mA, on the bench with no load. This seems like quite a lot to me - 4/5 of an amp just to turn the things over! The shafts felt fairly stiff so I thought I'd try a bit of running in, out of the water, with plenty of lubricant and checking for local heating quite often. After flattening the battery, I got 740mA on both motors, 370 on the port engine and 400 on the stbd. This still semed quite a lot - while I was investigating the shafts I discovered that there was no end float at all on the port, and only a smidgeon on the stbd one. I therefore stripped the motors out in turn, to show the UJs as pictured below. With the motors out, both shafts had a 1/4" or so end float, and the motors had about as much as motors usually seem to have. The socket part of the UJ is pushed right on the the motor shaft, so that the end of the ball is touching the end of it. I shaved a bit off the end of both balls with a scalpel, and reassembled things. Both shafts now had some end float and a bit more running gave me 600mA in parallel, 260 port and 290 stbd. So we seem to be making progress - I'll try a bit more dry running and see if the figures go down much more before I try running under load.  There is loads of side play in the shaft outboard end bearing, so that's never been tight, but I don't know what happens in the inboard one, and I don't really want to disassemble it. I wonder if there's an O ring in there - has anybody had a look?

Is anybody out there finding any of this in the slightest bit interesting?
Title: Re: Chinese 20 warships
Post by: DickyD on August 05, 2008, 09:47:17 PM
I am  O0 and you've had 1074 views.
Title: Re: Chinese 20 warships
Post by: Damien on August 06, 2008, 12:02:03 AM
In the words of my neighbour "Vellly intelestin" keep it coming m8
Damien.
Title: Re: Chinese 20 warships
Post by: MikeK on August 06, 2008, 08:19:31 AM
I'm not even into power, but have found your delving into the guts of this cheap import very interesting. Keep 'em coming please Tobyker  O0

Mike
Title: Re: Chinese 20 warships
Post by: MCAT on August 06, 2008, 10:14:19 AM
I fined this most interesting, as having a go at turning a static kit into rc for the first time. and I'm sure many points you bring up
will if not now, will help me in the future on builds.

keep going  Many Thanks   Mick
Title: Re: Chinese 20 warships
Post by: Captain Povey on August 10, 2008, 08:18:17 PM
Well I took mine to the lake today with Granddaughter intow. She was not too happy as it was not very impressve. It was very erratic in runing and the radio was a pain for the man next door so we gave up. I came back from my son's with the radio from an old car he does not use with the idea of simply replacing the radio with a decent one. Oh dear what a suprise was in store. I have now stripped it to the state of Tobyker's but not checked the motors yet. Thanks Tobyker for all you are doing on this I will be following your next moves closely as I am not very good with electronics bit. I think I will just put in the new radio and some electronic speed controllers. Any suggestion as to the size? Lets face it my granddaughter wants in running fairly quickly. For example I am unsure about using the existing on off switch and charging socket. Cheers Graham.
Title: Re: Chinese 20 warships
Post by: tobyker on August 11, 2008, 12:06:40 AM
I'm still bench running as I haven't set up my test tank yet to measure the amp draw (if that's what it's called) under load. And until I've done that, and probably measured the draw with nicer propellors, I can't make decisions about the ESC(s). And the number of ESCs, whether I use a BEC and 7.2 volts, or no BEC and 6 volts, and whether I use a mixer too, will depend on the amps and on the likely weight of the bits including the new Rx, rudders and steering servo.

One thing I will do is replace the breeze block weight with a bit of lead flashing - that will get the weight, which I shall probably have to reduce, lower down. This may also provide scope for extending the radio box down into the hull to make more space and get the weight lower.

The motors seem to be running a lot more freely with the end float on the shafts, and there is a lot less vibration. However one problem I am having is with the motor wires fracturing at the end of the solder - I  suspect you get a less damped vibration running the motors on a shelf rather than in the water. That is something else to be addressed before the deck gets screwed on again - the wires will have to be supported properly.

 I have yet to decide about the on/off switch and charging socket - they don't weigh much and plugging a charger in to the boat will be less likely to damage the wiring and fittings than uncoupling the battery each time, especially if you want to charge at the pondside from a car when your hands are cold. However I will let you know how I get on.

Nb the end (steel) weights weigh 62 grammes each, and the breeze block 195g.

This project is turning out to be far more fun, and interesting, than I thought it would.
Title: Re: Chinese 20 warships
Post by: Captain Povey on August 11, 2008, 10:08:47 AM
Thanks for that Tobyker. It is certainly more of a challenge than I had expected and will be worth it I think even if the bits I put in cost more than the initial cost. Cheers Graham.
Title: Re: Chinese 20 warships
Post by: malcolmfrary on August 13, 2008, 05:28:21 PM
To stop the wires fracturing they need some strain releif - simplest is to rout them past a solid it of motor and fix them down with a dab of bostic or similar.  This will give a graduated change from "rigid" to "flexible".  Have a look at where the wire comes out of your mouse - there will likely be an elongated grommet to give the same effect for the same purpose.
Title: Re: Chinese 20 warships
Post by: Captain Povey on August 19, 2008, 10:51:03 AM
Hello all, After a lot of thought, internet surfing, some basic measurements and conversations with two suppliers here is an update on the plan of conversion. 'Action' have been very helpful and I now have two P68a speed controllers and a P82 mixer. This lot is going to be powered from a 4.8v NiMH battery, fitted with the correct connector, care of 'component shop'. They are also a superb supplier and after I messed up the order on the internet they sorted it for me without problems. I also bought from them a charger that will just about do everything i want on this and other boats. All at good prices. So all I have to do now is fit it all. I am thinking of putting the Rx in the battery box now there is room with the aerial running around the inside of the deck and then up the superstructure. I have already removed the lump of brass that the supplied aerial was fitted to. The speed controllers and mixer can probably go in the old radio box. I have not checked the weight of what I have removed and what I am replacing it with but my guess is that it is about the same or even less. Cheers Graham.
Title: Re: Chinese 20 warships
Post by: tobyker on August 20, 2008, 09:50:24 PM
There has been a slight delay on mine while I got my propellors ordered - they should arrive in a couple of days and then I've got to get them to fit. I was also in touch with ACTion but I want to see what the amp draw of the motors is with the new props, as Dave recommended a different combination if they drew over 1 amp each. Meanwhile I'm building a support for the rudder servo and trying to work out a robust but light twin rudder linkage. Pics to follow when I get it sorted. When we've all got our destroyers sorted we'll have to get together and compare the results - but don't hold your breath! The whole point about a hobby is that it should be relaxing, so i try not to get pressured - If I don't do any modelling for a month or so, no problem.

I bought some tubes in Halfords today (the grandson is borrowing one of my bikes for the paper round and I appear to be his pit crew) and got a 15% off voucher. Very tempted to splash out on a cheap hybrid with narrow tyres on the strength of it.

 Capt Povey - please post photos to show radio fit. Are you going to rename her HMS Troutbridge?
Title: Re: Chinese 20 warships
Post by: Captain Povey on August 21, 2008, 08:28:54 AM
Hi Tobyker, I think your idea of naming her 'Troutbridge' is excellent and I had not thought of it. Maybe because Ramona was breathing down my neck and might have objected. Last night I fitted all the bits from Action and if the battery and charger arrive in the post this a.m. I will post photos of the installation as soon as possible. Please do not laugh at the workmanship i.e the holes for the wires were made with a soldering iron. Appart from the fumes it was less messy and easier than drilling. A good application of silicon sealer will finish the job. It sounds as if you are going to a lot more to yours than I am willing to attempt so I will be interested hear how the rudder works out. My assumpton is (and I may be proved wrong and end up with a red face) that with the voltage down to 4.8 volts the current draw in the water will not exceed 1amp per motor otherwise it will not work. Also at 4.8 volts it might not go very fast. Cheers Graham
Title: Re: Chinese 20 warships
Post by: tobyker on August 21, 2008, 11:34:43 PM
I dunno much about electrics but I thought a motor pulls the amps it wants irrespective of the volts or mAh of the battery. No doubt someone more familiar with the wriggly amps will set me right. Still waiting for postie with the props! I thoroughly approve of making holes using a soldering iron - I am planning to do some of those myself. Don't forget to launch her with a jug of, so far as I remember, "me old Mum Min's Humgrummit wine". Those were the days.
Title: Re: Chinese 20 warships
Post by: FullLeatherJacket on August 22, 2008, 07:27:51 AM
I dunno much about electrics but I thought a motor pulls the amps it wants irrespective of the volts or mAh of the battery. No doubt someone more familiar with the wriggly amps will set me right.

"Starboard lookout here...........Leading Seaman Jacket speaking"

Now there's a Techno-Monster lurking elsewhere on this forum who would probably wax lyrical for a few hundred words on the subject if he discovered us, so let's Keep It Simple and hope we stay below his radar...... ;)

More volts increases the speed of the motor, whereas battery capacity has no effect on its speed; only on how long it will run for. Motors are dumb animals and have no idea what sort of current they want; it's a produce of the resistance, the load and the voltage (and probably a few other things which T-M would list at length). You can't alter the first so you play around with items 2 and 3 until you're happy.

Happy?

FLJ
Title: Re: Chinese 20 warships
Post by: OMK on August 22, 2008, 08:25:05 AM
Happy? HAPPY?? I'll bet he's bleedin' delirious!

How do you do it, dude? Just HOW do you DO it?!!
(Perhaps you would be kind enough to pass it on to T-M).
Title: Re: Chinese 20 warships
Post by: DickyD on August 22, 2008, 08:41:19 AM
Wonderful Dave, even I understood that. Would the T.M. be a certain B.P. by any chance ? :-\
Title: Re: Chinese 20 warships
Post by: Captain Povey on August 22, 2008, 06:04:38 PM
Hello All, I am glad to say the battery and charger turned up today so the final wiring took place. The bench test proved to be better than expected and the electronics bits worked brilliantly (thanks Dave). I had not realised that the mixer actually reversed the inboard motor on a turn so steering will be better than expected. I had to fiddle a bit with the wires to get the prop rotations correct and the steering to go in right direction and then realised that the radio I borrowed from my son had servo reversing functions on it anyway. Doh! So next was the bath test, without superstructure, just to check it all worked under load. This also proved to be very successful and no problems appeared even with the nose wedged into the end of the bath and the throttle full on. Now its on to the reassembly and application of sealer to all those holes I made. I noticed that on mine the deck seal had not been fitted properly at the bow and has now been repositioned. Can anybody tell me the purpose of the hole at the stern and the point of the polystyrene in fill? I have also plugged the two holes in the rear deck that had rubber bungs in them. Ramona is now missing some large plastic knitting needles. I think it is a good idea, as already suggested, to replace the ballasting weights with lead as this will get the weight lower and maintain stability. I also reattached one of the missile pods with a screw. Not pretty but if another refit is needed then it can be done just by unscrewing things. Here are a few pictures of the lash up so far. Cheers Graham
Title: Re: Chinese 20 warships
Post by: Captain Povey on August 22, 2008, 06:07:32 PM
Well I did not get all the pictures into the last post so here goes again.
Title: Re: Chinese 20 warships
Post by: Captain Povey on August 22, 2008, 06:10:05 PM
Well it looks like I have a problem Houston. Yep it was being dumb again.
Title: Re: Chinese 20 warships
Post by: Captain Povey on August 22, 2008, 08:36:22 PM
Well I have just replaced the weights with lead. Not as striaght forward as I imagined. Getting the weight right was ok but getting it distributed was critical especially accross the beam. More bath side time spent than I imagined. Here is another picture I missed off previous posts. Cheers Graham
Title: Re: Chinese 20 warships
Post by: Captain Povey on August 23, 2008, 10:00:11 PM
Well it is all back together and ready for a sea trial tomorrow. Granddaughter has already been on the phone to ask if I am taking her boat over tommorrow. Fingers crossed for a success and a big improvement on the last run. I moved the life boats to allow easier access to the screws that were underneath them should it be necessary to undo them again. I have not put in all the plastic bungs over the screws yet and I may well plug them with more turned down grey plastic knitting needles at a later date. I replaced some of the rather poor quality self tappers with some stainless ones. I have one queston for the electronics boys out there regarding charging the battery using the socket on the boat. When I plug the charger in neither the led on the charger or boat is lit despite measuring a voltage at the battery lead socket. So just to be sure I charged the battery out of the boat using the Tamiya lead and the led on the charger then works. I noted that it is critical to replace the battery in the same position every time to ensure an even keel. If all goes to plan and weather permits as it has just started raining here again pictures will be posted. Cheers Graham.
Title: Re: Chinese 20 warships
Post by: Captain Povey on August 25, 2008, 11:16:51 AM
Success, it worked and granddaughter was happy. I was concerned that she (the boat not granddaughter) did not want to turn to port at one point but then learnt that the steering works best at slower speeds. She also took on a list due to the battery moving. Once again accurate ballasting is critical. Sorry to say that I was so busy with this and my other boat that I forgot to take some pictures but the family did so I will post some when available. One other observation is that the two holes for the rubber bungs in the rear deck may have a use so bunging them up was probably not such a good idea. When I took my other boat out of the water after an hour or so she had taken on some water up the starboard prop tube. If this has happened on the destroyer then the only way to drain it is out of those bunged up holes. Cheers Graham.
Title: Re: Chinese 20 warships
Post by: FullLeatherJacket on August 25, 2008, 03:45:32 PM
the steering works best at slower speeds.

Point of info for anyone who fancies emulating the good Captain's set-up;
With no throttle applied, the rudder command has no effect, but squeeze a touch of forward or reverse speed and the inboard motor goes into reverse. As you increase the forward speed so the mixer gradually reduces the degree of "mix" until, at full speed ahead and full rudder, the inboard motor is just stationary. It's a "compound" mixer which offers the best compromise between a 50% and 100% mix. The bigger P40C has the same software, whereas the Full Monty P94 has fully-adjustable mixes from 0% to 100%.
The gen on mixers is here
http://www.action-electronics.co.uk/pdfs/Twins%20Ver2.pdf
PM me for any further info or queries.
FLJ
Title: Re: Chinese 20 warships
Post by: Captain Povey on August 25, 2008, 09:10:39 PM
Hi FLJ, Thanks for the explanation of how the mixer works. I was sure it was somrthing like that  :D but I couldn't seem to find the words. Cheers Graham. O0
Title: Re: Chinese 20 warships
Post by: Weeds on August 25, 2008, 09:22:16 PM
link for the mixer and price?
Title: Re: Chinese 20 warships
Post by: tobyker on September 01, 2008, 10:27:16 PM
Weeds, look at the ACTion electronics website in the Traders area.
Capt Povey and ACTing leading seaman Goldstein- pl note that at 0900 next Friday, Radio 4 is doing one of the "Re-union" series on the Navy Lark - with Sub-Lt Philips, Wren Chasen and others.

WARNING - THIS MAN KNOWS REMARKABLY LITTLE ABOUT ELECTR(ON)ICS

I finally got a tub of water, the destroyer, my AVO meter and some time all together in one place. The Stbd motor drew 0.35A off load, and 1.03A with the standard plastic 2-bladed 30mm prop fully submerged - about 0.65A submerged to the hub.
I then put on a 30mm Raebosch brass 3- blader, which drew .022A off load. Either my test set-up is wrong, or the heavier brass prop is acting as a flywheel, which might mean the motor needs less amps to keep it running. (The plastic 2-blader doesn't register on my electronic scales, and the brass one reads 6g. My set of scales which would show the weight of the plastic prop are 400 miles away weighing bits of car valve gear.) The brass prop drew 1.2A fully submerged.

Mind you, these readings of just over 1A in still water with the 7.2V pack suggest that you should be quite safe running ACTion's tiny ESCs on 4.8V - as Capt Povey appears to have demonstrated.

This suggests that the brass prop of the same dia as the plastic one is putting more watts into the water, and the boat is too fast anyway. Also, looking at the 3-bladers, they look far too big for the hull, though for tank steering they probably need to be. I have therefore ordered some smaller props and will run the test again with them, a freshly charged battery, and a new battery in the AVO. I've made the rudders and a servo mount, but haven't yet worked out a light but robust linkage which I can bolt out of sight under the deck.

What's the best hybrid bike I can get for 350? any ideas?
 
Title: Re: Chinese 20 warships
Post by: Captain Povey on September 02, 2008, 09:20:30 AM
Hi Tobyker, Nice to see you back on board and doing some excellent experimental work.  8) I cannot comment on the props as I have never done anything like that. My only comment regarding loading form the different props would be that the heavier brass one will have a larger start up current draw because of the inertia. Thanks for the info on the Navy Lark I shall listen out for it. I am still waiting for the pictures of the destroyer from the family who have been on holiday. I do not know much on bikes although in my younger days I rode a few.  ;) Hybrid bikes are new to me so does an electric one count? I have seen those for around 400 so maybe a second hand one would in the price range. I saw a man on a uni cycle in bath the other day and with only one wheel perhaps they come at half price. Sorry just being flippant as usual. Cheers Graham.  O0
Title: Re: Chinese 20 warships
Post by: tobyker on September 10, 2008, 07:56:03 PM
Rainy day and waiting for propellors (again) so out with the plasticard for servo mount and rudder tubes. The shafts I am using come from when I worked for a metal tube broker - does anyone remember when ballpoints used brass ink tubes? Of course no obtainable tube fitted the biro tubes so i had to take the next largest plastic tube, slot and re-glue it round the shafts twice, and then raise a burr on the end of a biro tube and ream the tubes out a tad. I still haven't worked out a linkage but it may be easier when everything is in position.
Title: Re: Chinese 20 warships
Post by: Captain Povey on September 12, 2008, 11:32:28 AM
That is looking very good Tobyker. Unfortunately my photos have still not arrived. Cheers Graham
Title: Re: Chinese 20 warships
Post by: Captain Povey on September 15, 2008, 09:04:34 AM
Hello all, At last I have a picture of the reworked destroyer on the water. The rest of the shots were done in a video format so if somebody can in instruct me in how to edit and upload to U tube I will put some of that on and post a link to it for those interested. Cheers graham.
Title: Re: Chinese 20 warships
Post by: Captain Povey on September 15, 2008, 11:13:24 AM
Hi All, I have posted a video on u tube. If I have done it correctly it will be on http://uk.youtube.com/watch?v=GkXzo34TFGc, Cheers Graham.
Title: Re: Chinese 20 warships
Post by: Captain Povey on September 15, 2008, 11:39:32 AM
Here is some more of the destroyer plus a bit of Smit Nederland.  http://uk.youtube.com/watch?v=JZauR9vaoho Graham
Title: Re: Chinese 20 warships
Post by: tobyker on September 16, 2008, 11:43:01 PM
They are a bit quick, aren't they? There's lots of them on Youtube, too. I've started fidling about with linkages and will put up the pictures as soon as I've got them sorted.
Title: Re: Chinese 20 warships
Post by: tobyker on September 18, 2008, 10:51:45 PM
A productive couple of days - got the rudder linkage 90% sorted - just got to seal where it passes through the rear bulkhead, as I may well leave the steerage free-flooding, because of the difficulty of sealing the aft deck. The servo, mount, rudders and linkage weigh 28g, so that will have to come of the aft steel weight. The radio box is presently bottom-loading, but I want access to as much as possible, so I've cut through the deck beneath the helicopter deck to make it top-loading, and am building a 3/4" coaming round the hole. I'm taking the radio box a bit further aft than the original, and will make it deeper with a fixed bottom, as I'm binning the breeze block weight and replacing it with lead flashing. Pics to follow when I've finished the new radio box. Not made up my mind yet exactly what's going in it, as I need to see what sort of amp draw and thrust my new props give me, when they arrive.
Title: Re: Chinese 20 warships
Post by: tobyker on October 09, 2008, 08:51:06 PM
Things still coming along slowly, but no sign of my smaller props yet. However as pics show, I've got a rudder linkage sorted, and have lenthened and deepened the radio box, with top access hidden under the aft superstructure - the bit with the helo deck. I'm binning the helo, as it's too heavy and too high up. The breeze block weight is out, too, and it's supports removed. The radio box now goes right back to the deck mounting pillars just forrard of the motors - I've installed slightly thicker motor wires and led them through holes in the motor mounts so they'll go under the radio box (over the lead weight - if I still need weight!) and come up somewhere inside it near the ESC(s?) I'm still waiting to test the amp draw with the new props so I can decide whether to go for 4 or 6 cells, and depending on that, whether to go for combined screw and rudder steering or a single ESC. I also need to weigh the new props so I can see if I still need any weight between the prop shafts, where the 60g steel slug was.In order to simplify access I'm going to locate the aft superstructure with a magnet, and glue the bridge and the middle bit with the boats on, together. As the quadruple missile launchers as presently fitted foul the foredeck mounting screws, I'm going to mount the missile launcher ramps on to the side of the bridge structure, so they come off with it. The aerial I shall probably mount under the foredeck. For info, all the white plasticard is 1mm thick. I'm still not quite sure what to do about the free flooding steerage compartment - if I seal it I'll have to seal the aft deck to the hull, and that could be tricky. It may be better to leave it flooding, and try to seal the hole where the rudder linkage goes through the aft bulkhead as well as I can. The trouble is, the hole is quite near the sealing lip in the deck. This boat is representing good VFM in that all the problems are keeping me thinking for a long time and even with the ESC and other radio bits the cost per month should be quite reasonable.