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[Phil22]

Oh she's a stunner @JimG!! Would you have any links to the build?

[JimG]

Thanks Phil, I have no links or photos of the build as it was built at around 15 years ago before I joined Mayhem and I didn't keep any photo records of builds at the time.
Jim

[Phil22]

Thanks for the reply @JimG. I took a closer look at the Parat kit, it looks like a complex build with a really interesting steering setup. Well above our experience level but again a brilliant result!

The moorings (terminology correction welcome) and the stair sections are now the last of the details included in the Banckert kit.






Early on when building the superstructure, the stairs (port and starboard) were also measured and cut for height and the fitment was snug. A nod to Billing Boats.



With the layering up of paint and whatnot, the forward pair would no longer fit. Now each set of stairs has had 2mm of material removed and been rejoined. For each, two cuts were made and worked on evenly to prevent snapping any of the steps. It didn't matter too much if the cut wasn't super straight because flipping one cut halve over evens things out again.



A trip to the 100 yen shop (pound shop back home) saw us buying a 10 pack of travel size toothpaste for the tube caps. As well as having minty breath, the caps were the perfect size to cover the bow portholes from the inside making them watertight. The same has been done for the anchors and the winch chains into the deck.









The propshaft is on its way from CMB along with some other bits. Presently we are looking for a basic but decent transmitter (not the type with a wheel on the side), a 700~750KV brushless outrunner and an esc.

A while back I bought a tank mounted machine gun kit by Tamiya as it contained a load of mechanical looking parts. The fire extinguisher on the sleeper wall is actually part of the muzzle assembly. There will probably be more furniture added on deck once we know she isn't top heavy. Fingers crossed hahaha.

Thanks for reading =)

[Phil22]

Hi All,

Some progress shots of the build this week.






Having never made a bilge keel, it made sense to simplify things by affixing both sides together then work to make the overall shape symmetrical.







Here is the test effort (a better stand definitely needed and on the to do list)



The finished versions (below) are slightly shorter at 185mm.










We'll work on the rudder blades next while we still get the various electronic components together.






This small brass nut and bolt is for connecting the kort nozzle to the hull. It's the last functional part of the fittings kit left.

[Martin (Admin)]

Very Neat work!     



 

[Phil22]

Thanks @martin : )

Finding today that images though uploaded to an album are not generating previews or Full BB codes.
The BB code can be manually edited (from older ones) to get the newer images to show in a post.

[Phil22]

Hi MBM,

TOP GEAR fashion!
This week....
We put some holes in a hull !!!

An understandable necessity but from a newbie POV quite daunting XD

Pilot holes for twin rudders. The original kit part doesn't really settle in one spot but it is helpful in getting an approximate idea and for the spacing between holes. Noted that previous builders have produced their own sturdier rudder mounts.




Both holes still need opening up to 4mm for the collar fittings.




Above deck access




The mock up is all held together by tape here. A couple of long brass sections have worked well in helping (our aging eyes) to align the components.



By design, the 85mm brass bar linking the kort with the hull requires a couple of bends so the profiles are met. Think we might need to buy a vice to do this. I guess a hammer might simply flatten it out... There is a small piece of ply expoxied inside the hull and 2 x 10mm brass nails (supplied) to affix the bar with. Will switch them out for brass screws.











Would like to ask for guidance on the next part. Invested in one of these =P



The instructions that came with it cover models 301-00 to 301-06, there is no mention of 301-22.
It isn't too clear either about how to correctly prep it for installation. Hoping these images help explain our stuck points:

1. There is a wide nut on the prop end with one side of it beveled.
- Would the beveled edge face the prop or the motor?
- Is this nut to be tightened up toward the motor or down to the prop?
- Is a second nut needed for the prop? (washer required?)



2. This widest section has movement and can be moved in the direction of the motor.





At which of these points (yellow, red, blue) should we expect there to be slight play and how much?



Thanks in advance for any information to help.


The last towing guide has been attached



Cheers!

[SailorGreg]

To answer your questions - the large nut is a locking nut and should be tightened hard against the propeller.  It stops the propeller unscrewing itself, so make sure it is properly tight! It might also be worthwhile to put a washer between the nut and the plastic bearing in the end of the tube.

The large piece on the inboard end is loose to allow you to make adjustments to the final length of the tube to fit your hull.  Once you are happy with the length, that piece should be epoxied into place so that it can't move.  It should be pushed as far onto the tube as it will go.  Once everything is in place, there should be just a perceptible movement of the shaft back and forth, but no more.  If you tighten everything up so there is no movement at all, you will probably get binding at some point.  Just ease the locking collar at the inboard end by 0.5mm or so to give a bit of freedom.

Hope that helps.  Nice work by the way!

Greg

[Phil22]

Huge thanks Greg!! Your information helped us a lot. Really appreciate it.

Left side = binding example | Right side = given 0.5mm of play



The Raboesch shaft length is good as is (probably 4cm longer than the kit shaft) so we can have
the large piece inboard at its shortest position. We'd be epoxying it to the outer shaft within the yellow area, right?



The kit prop has a brass internal thread (open at both ends), this allows the shaft to keep turning through into the cone section.
We will by a brass prop and assume the shaft won't do this and so would use less thread.



Is there a common case where a narrower nut may be required to lock down the prop? The reason to ask is the prop nut in the kit is around 70% thinner than the Raboesch supplied one.

Lastly, is it okay to completely remove the inner shaft when fitting the prop?

[Taranis]

The long nut at the prop end (nut F) is not threaded all the way through. The unthreaded part goes towards the prop tube and you screw it up fully, this ensures that no thread of the prop shaft is visible or inside the tube Delrin bushing.
There is no need for any other nuts you lock the prop against this one.
I recommend a drop of loctite.
The shaft free play is controlled by the locking collar at the drive end as Greg said.


You can remove the shaft from the rudder end yes never pull the threaded part through the drive end bearing. However I don't see a need to do that? just hold the nut F with a spanner and screw the propeller up to it.


If the thread is too long for the prop then shorten it to suit. You don't need a washer between the prop and the nut, this achieves nothing in fact possibly counter productive.
Great build 


one of mine

[Phil22]

Hi Andy,

Thanks very much for your help and for posting the pic to demonstrate the fit.

The long nut at the prop end (nut F) is not threaded all the way through. (Nice one for pointing this out) The unthreaded part goes towards the prop tube and you screw it up fully, this ensures that no thread of the prop shaft is visible or inside the tube Delrin bushing. There is no need for any other nuts you lock the prop against this one. I recommend a drop of loctite.

Roger this! Nut up full to the delrin bearing.




The shaft free play is controlled by the locking collar at the drive end as Greg said.

Part B is pushed down against the outer tube (Part A), there's a 0.5mm gap between B and the washer/collar.



The 0.5mm of play allows the inner shaft to go in and out that much at the prop end.



Should B be expoxied to A to prevent it from turning? Or is B supposed to turn?



You can remove the shaft from the rudder end yes never pull the threaded part through the drive end bearing. However I don't see a need to do that? just hold the nut F with a spanner and screw the propeller up to it.

We might be alright not to disassemble, the access to the nut might be blocked by the kort. We'll see later when everything is in place ; )

Again thanks in advance, we are nearly there with our understanding (hopefully).

Cheers!!
Phil

[Taranis]

B is supplied loose so you can modify the length of the tube, it must be glued in place when you’re happy with the length otherwise water will leak into the hull.

[Phil22]

Cheers to both Andy and Greg for your valued guidance. Things make sense now, thank you.

[Phil22]

Happy New Year Everyone!

Resolutions:
1. Finish boat
2. Finish boat
3. Lose middle-age rubber ring

More parts reached us in Tokyo from CMB. Our thanks to them!

@subculture and @taranis kindly shared suggestions/links early on in the build for the electronic components. The plan was to go with with:

- 40mm brass prop
- A 28mm to 35mm 700kv (6v) brushless outrunner (direct drive)
- Battery: 2s lipo/Life
- 30A Esc - like https://hobbyking.com/en_us/hobbykingr-tm-brushless-car-esc-30a-w-reverse.html

It’s no secret that a lot of places haven’t the stock these days. So far we’ve managed to gather together the following:

Roxxy 750kv C28-34-12 Brushless Motor



Spektrum DXS Transmitter



Spektrum AR410 Receiver



Futaba Servo S9570SV (High Voltage)



Universal Joint 4mm - 3.2mm



Roboesch Propeller 40mm 4 blade RH





Request
- With these components, would a 30A unit like this (amazon Japan link) be good to go with?

https://www.amazon.co.jp/-/en/Mtroniks-Tio-marine30/dp/B00A3NF8PG/ref=sr_1_43?m=A3I90NWAJ6Z1EM&qid=1642491283&refinements=p_6%3AA3I90NWAJ6Z1EM&s=toys&sr=1-43

- What would be the recommendation regarding batteries in terms of brand, specs (mAh etc)?

As for the brushless motor, some things clicked better after examining it in hand. For those like ourselves who’ve never used/handled one, the outer bell (widest section) rotates and so does the central pin. The section with the wires remains stationary.



Bit puzzled TBH with this one...







Perhaps none of the parts included are used and we need a small motor mount, that has a large enough center hole to allow the universal joint grub screw to reach the flat area.




Thanks in advance for any help.

[Taranis]

Hi Phil I converted to waterproof speed controllers for cars and found them perfect for the job.
Mercantic Hoga Boulogne Etaples and Boothbay lobster boat all use one Riva Aquarama uses two

https://www.modelboatmayhem.co.uk/forum/index.php/topic,66723.msg723418.html#msg723418


Batteries
https://www.modelboatmayhem.co.uk/forum/index.php/topic,66723.msg723528.html#msg723528

50mm propeller  3cm shorter  IMG_0704-1920.mp4

[JimG]

The motor is of course designed for electric flight where the propellor fits onto the threaded adaptor. If you want to use the coupling you have then you can either open out the hole in the motor mount to fit or cut the individual cross sections from the center. ( or get another coupling which will fit the threaded end) They only need one screw each to fit to  the motor so you can have a bigger gap in the center. Once screwed to the mount in the boat the arms will be rigid. These motors are often fitted to the nose of models by mounting the motor directly to the front bulkhead with a hole in the center of the bulkhead  to allow the shaft through and they use a collet type adaptor onto the shaft to get a threaded section to mount the propellor.
Jim

[Taranis]

I use these and mount them so I don't need a clackety clack UJ. Solid coupling is better.
https://www.cornwallmodelboats.co.uk/acatalog/360-400-Size-Motor-Mount-70201.html

[JimG]

As an alternative to mounting the motor as it comes, the shaft on an outrunner is normally held into the endbell by grubscrews allowing bent shafts to be replaced. The circlip on the static end is there to take the endload when used with an aircraft propeller. You can remove the circlip allowing you to remove the rotating bell than remove the shaft and fit it in reverse so that the end with the section ground away comes from the front of the motor not the back, this would allow the coupling to fit easily. There is no need for the circlip as the end loads are take by the shaft not the motor and the magnets hold the rotating bell in place normally, just make sure the shaft is fully through the rear bearing.

Jim

[Phil22]

Thanks so much Andy! Really appreciate you sharing the photos to demonstrate along and with the movie clip. If our Banckert goes half as well as your vessel, we'll be well chuffed. Many thanks to you Jim too for sharing your knowledge of brushless motor construction and the mounting options. I'll have a play and see what might work best for our setup.

Again, each time it's with thanks to you and the MBM members who help us to progress. We 100% appreciate it!!

[Phil22]

This provided a good introductory read on lipos: https://rogershobbycenter.com/lipoguide 

[Phil22]

A few more orders have arrived this week.

We’ve gone for the same Quicrun esc as recommended by Andy, see superb build pics (above).



connectors






Having initially been more alarmed than I’d like to admit about Lipo batteries in general, I think I’m at a point now where I feel okay (more-or-less) about having them in our home. The takeaways (really open for correction here) from various Youtube and Google searches are:

For a 2S Lipo | 7.4V | 80C | 5200mAh | 38.48Wh

- balance charge at 1C or less (up to 5.2A) (believe our selected charger has a max of 5.0A)
- charge on the same day as we intend to sail
- don’t let the charge go below 3.2V per cell
- don’t store at full charge
- a storage charge can maintain the battery around 6 months
- if any swelling or cracks appear cease usage
- place in 10L of salt water for 14 days before disposal



An initial battery check gave these values:

3.839V and 3.794V

How should we interpret this reading? Bad, fair, good for example.

A zip-up Lipo bag is on order, one of those with a hole in the side for charging.
Is it worth to keep an ABC or dry chemical fire extinguisher at home? I think I know what my preference is here , interested to hear about recommended precautions.

We'd be appreciative of your thoughts and advice.
Cheers!!
Phil

[Phil22]

Hi MBM,

A couple more pics of progress this week.
On the ESC, switched the mini Tamiya connector for an XT60. 



The electronics were all connected for the first time. We did get our DXS transmitter to put the
motor into reverse, but subsequent playing with the ESC has lost it again. A programming card is on the way so we'll keep tinkering. (Update: now sorted)



The 40mm propeller went in great with a few mm to spare inside the kort. There is a small bolt also inside at 12 o’clock that needs to be accounted for.



4mm holes were made for the rudder tubes.





Before beginning our Banckert, we especially tried to find clear shots of the this area. These pics may be useful to other builders, (we're noobs: use at own peril haha)







Cheers!

[Phil22]

Some more pics from the work completed last week.
Put together a battery box for the 2S lipo, it contains a shallow track to the let the battery lie flat. By design the battery itself has a slight hexagonal cross-section.





The kit's rudder mount has been epoxied in. Some reinforcement will be added later to make it more robust.





Question: When the time arrives to fill the collars with grease, is there a recommended way for installation (or nuggets of advice) that may help with this?



The propshaft ..... a lot of measuring, pondering, guessing took place for the install XD. It eventually gave way to "Oh... let's just have a crack and see what happens..." Anyhow, I think it went well for a first go.

All along we were thinking the outer tube would sit flat on the supplied piece of ply giving us the 'required' angle. Maybe it should and it was our installation that is off hahaha. It didn't sit flat (red arrow). This angle is dependent on the part outside of the hull that the tube passes down to the kort.



A small wedge (left) was used to make a little alignment correction



a second was added on the right to set it in place.



Early on I made a right pigs ear of the kit piece here when trying to fit the propshaft provided by Billings. It was saved and helped to form a template for a replacement part. I went with a flat top edge for an option as other builders have mounted the rudder servo in this area. We'll see how it goes.



The replacement has been epoxied in





The Raboesch propshaft we got is around 180mm in length and it almost marries up exactly with motor. The mount needs raising a few mil, so looking at the best way to do that. Wood might split at the required thickness if we screw through to the base board. Maybe we can look to raise the base a fraction instead. That's for another day.



Thanks for reading.

[Stan]

Hi Phil two models seen at Kirklees MBC. The one on the  wall is the model that suffered damage after been dropped.


Stan.

[Phil22]

Thank you Stan for reaching out with the advice to reinforce the bow. We're seeing what we can get a hold of here in Japan that will be suitable. Great to see these excellent builds on the water. Cheers for posting!!


Phil