Arkmodel Dragon Shark II Motor shaft fitment

[vdubsport]

Hi All,

I just recently purchased a 1/72 Arkmodel Dragon Shark II. During test fitment I noticed that the drive shaft hangs up in the rear tail wimble brass collet and that the drive shaft doesn't go all the way threw the collet. The other weird part is that the brass collet is threaded and not smooth like i thought it would have been for the drive shaft to spin freely threw. When I try to spin the shaft it gets hung up on the threads. I have thought about filing the collet down so the shaft will fit all the way threw and spin freely however i really don't want to make modifications if this is normal. Please see pictures below.

Has anyone built this kit before run into this issue? Any other thoughts or suggestions on how to resolve this?

[bob_eissler]

Looks to me like picture #3 is exactly the fit you want. The bushing is also the thrust washer. Very hard to get the prop off after screwing it on. I would add grease to the bushing before assembly.

[bob_eissler]

Here is a link to pictures of my Dragonshark build: https://photos.app.goo.gl/7vANaYcvad9rbTuZ7 . Don't have a great picture of the shaft and prop but they may help you some.

[vdubsport]

Thanks Bob!

[vdubsport]

Has anyone had issues ordering from Arkmodel directly recently?

I went to order my Ballast Control Unit (BCU) today and received a HTTP ERROR 500 when going through the checkout process.

Does anyone know where I can order one or something similiar other than Arkmodel?

[bob_eissler]

I haven't tried their site in years. They have been putting things up on ebay and are even selling through Amazon. They have always delivered as promised. Also, as you can tell from the instructions, their english is very poor.

[vdubsport]

Thanks Bob.

I bought the kit through Amazon a weeks back with no issues. Unfortunately I tired to find the BCU on Ebay, Amazon, and the internet in general with no luck.

I was wondering if I could find another unit made by a different company, or use something different in its place?

[bob_eissler]

That is a very unique controller, looks almost as nice as a Engel controller.

[vdubsport]

Thanks all give them a look.

I also just messaged Arkmodel through their Facebook page.

[JWLaRue]

If you don’t get a response from Arkmodel, send me a PM. I have a BCU for their Type 212 that I’m not planning on using. We can probably work something out.

-Jeff

[vdubsport]

JWLaRue, thank you will keep you posted.

bob_eissler,

When your were assembling your DragonShark did you have to trim your WTC tube?

Im finding that the one they sent me is about a 1/4 two long. See pictures.

Any advice on how to resolve this? I really don't want to risk damaging the tube by trying to cut it.

I went to hardware store this afternoon and purchased new longer 5mm rods but I'm finding that they are a bit flimser than the ones provided bu Arkmodel.

[JWLaRue]

What does the other (motor) end cap look like? On my dive module the threaded rods go through the end cap and have o-rings and nuts to secure it. There is enough 'extra' rod that I could add a nut or two...meaning that I could move the threaded rod forward if needed.

-Jeff

[vdubsport]

The setup is similar, the rod threads into a decorative nut, washer, and then the o-ring on the motor end. If I change the decorative nut to a standard one I can get about an extra 1/8 of an inch. I just tested this and I get close but unfortunately not enough close the hull lid.

[apa-228]

I'm not familiar with this unit, so I may be wasting your time, if so, sorry. It looks to me that the nuts and washers holding the filler piece away from the inner disc could be made thinner. If you used a toothed lock washer you would gain about half the space taken by a regular lock washer and filing the nut down could also buy you the closure you are looking for.

[bob_eissler]

Jeff is right. You want the nuts on the end you are showing to be flush with the end of the rod and take up the extra length on the other end with the o rings. I went back and did a final adjustment of all of the bulkheads after getting the end cap on and working. You will have to do some filing to the end cap's tabs to get it to turn on on easy enough and I still need to use a screwdriver thru the u bolt to twist it off because of the friction of the 0-ring. I think using threaded rods to hold the wtc insides together makes assembly very tedious. Way too many nuts to thread in place. I suggest you start on the piston tank and get it working before adding the front and back onto the sub. Mine needed a lot of lead under the ballast tank to get the sail under water.