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G'day people,

 

This has been an on again off again subject. I like the shape of the boat and the inclusion of the two Dry Deck Shelters (DDS) is an interesting  feature.

 

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The USS Kamehameha is a Benjamin Franklin Class submarine that has been converted for Special Forces SF operations and so avoided decommissioning (although now retired) along with the other BF class boats.

The kit is typical Mikro Mir and they have done a good job overall. A small but useful PE fret is included for the screw and some conning tower details. From what I have read by those more knowledgeable than myself (which is most people!!), the biggest issues to correct are at the back end. the rear dive planes are a little short in chord and the fixed portion lacks the prominent vertical end plates which were specific to the BF boats.

 

Progress was rapid however, the fit was not great. As I said, this is a typical MM kit which means you do not have a great deal of alignment aids and surprisingly, only a modicum of filler was used to remediate the hull seam which is split into two horizontal parts. The separate upper casing however was another story. Whilst the fit at the rear was acceptable, the forwards profile did not have any gaps but it did have a significant step to the hull. The real deal blends more gradually and this required much sanding and blending with putty to achieve a good fit. I managed to lose the passive sonar dome, I threw it out thinking it was just excess mould material. I ended up scratching a new one from some scrap resin off cut.

 

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MM supply a small curved part fro the conning tower windows -which I promptly broke. I ended up using some clear plastic sheet from a CD jewel case instead. This was cemented in place then sanded to shape and successively sanded and polished back to clarity

 

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To correct the dive planes. I added some plastic stock to the dive planes and sanded to shape. I also filled in the hinge slot as this was incorrect.

 

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That's all for now, thanks for looking,

 

cheers,

 

Pappy

 

 

 

 

 

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G'day people,

 

More work, this time it is the DDSs.

 

001(2).JPG

 

The kit supplies two of these and although the doors are provided as separate parts, no interior of any kind is supplied. I decided to make a very crude representation by inserting a short section of aluminium tube and adding a small rectangular section of plastic card to provide a floor. There are also a couple of 'lumps' on top of the DDSs which I  represented using some plastic sheet off-cut suitable shaped.

 

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I have seen some really nice 3D printed DDSs but these would have cost me double the asking price of the kit and I could not justify it so I will have to make do with some plastic strip and elbow grease instead!

 

My initial plan was to add the small end plates  to the rear horizontal fins but this attempt ended in disaster. Making the four identical fins was easy enough but getting all four of these aligned and parallel was like trying to wrestle with a bag of kittens. I decided to come up with a new plan. This time I made two identical end plates, one for each side incorporating the upper and lower sections in a single part. Next I carefully sawed away a small section from the outer edge of the forward (fixed) section of the aft dive plane. Once the cut was cleaned up, the end plates were simply butt glued and checked for squareness.

 

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Result!!

 

All that remained was to attach a small shaped section of plastic card to represent the end of the dive plane

 

cheers,

 

Pappy

Edited by Pappy
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1 hour ago, Courageous said:

Good going Pappy, nice attention to detail.

 

Stuart

G'day Stuart,

 

Thanks very much, I was beginning to think I was the only one following along! It appears that MM have done a fairly decent job  and I am just adding a few tweaks.

 

MM kits usually include a small brass PE fret and this kit is not exception however, in this case the details are limited to a part for an early conning tower configuration (which I will not be using) and the screw, which I will be using. The PE screw needs to be added to the rear plastic hub and the blades bent

 

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And just for fun, the screw was temp fitted

 

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Thanks for looking,

 

cheers,

 

Pappy

 

 

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Looks ok to me, the long, curved edge is the leading edge and they are right hand turn (looking towards the front of the boat).  But posting the image, it's the blade pitch that is wrong, the curved leading edge should be pivoted towards the front of the boat, not towards the rear, if that makes sense.:

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Blade pitch is hard to see in that first image, easier to see in this one:

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Edited by Woodstock74
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That's another reason I'm no fan of the PE screws, blades go all akimbo.  I've just taken to drawing my own up and printing them.  Sturgeon 637 class:

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Edited by Woodstock74
Picture issues
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30 minutes ago, Woodstock74 said:

Looks ok to me, the long, curved edge is the leading edge and they are right hand turn (looking towards the front of the boat).  But posting the image, it's the blade pitch that is wrong, the curved leading edge should be pivoted towards the front of the boat, not towards the rear, if that makes sense.:

Yes, there's a minus sign for the pitch (or, it is now a left-handed forward-skew prop). Can you bend the PE in the opposite direction?

Edited by foeth
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Good work chaps!

 

I will have a crack at bending the blades the opposite way instead

 

cheers

 

Pappy

 

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2 hours ago, Courageous said:

A good eyeball from @Woodstock74 & @foeth. I was looking at the prop and thought that something was odd...

Those 3D options are an idea but I wouldn't like to clean them ridges..

 

Stuart

Really not a problem as the print step is .02 mm.  So the ridges, in this case, are very tiny, and for most part go away with some primer.  

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I always have problems with those etched props......

 

The 'shaft' linking each blade to the circular hub is so delicate that it is too easy to snap off a blade whilst bending in the pitch.

 

On my Blue Ridge Models USS Albacore, they provide a neat resin plug to set the pitch - you just place the etched brass into one plug, place the other plug

on top and gently squeeze them together...... easy peasy......

 

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Although the pitch is set relative to the hub, the blade is still flat along its length - the plug doesn't cater for the change in pitch along the length of the blade....

 

The best solution is Mike's 3d-printed props - scale thickness with correct variable pitch....

 

Ken

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airscrew.jpg

 

A prop with a constant pitch will have a twisted blade and a flat blade has a radially increasing pitch 😁 But I agree, a 3D print is probably better...

 

 

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8 hours ago, Woodstock74 said:

That's another reason I'm no fan of the PE screws, blades go all akimbo.  I've just taken to drawing my own up and printing them.  Sturgeon 637 class:

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Where were you when I needed 5-bladed screws for my Nautilus project? The ones I got off Shapeway will do in a pinch, but their blades are overly thick. Yours look to be much more to scale.

 

-Bill

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G'day people,

 

Firstly, thanks for pointing out my dumb mistake ref the screw blade pitch. The correction was relatively easy, I simply bent the blades in the opposite direction, luckily, the brass has not work hardened and none of the blades snapped off

 

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So, the painting can now begin,

 

I have given the lower hull a base coat of white primer in preparation for the red oxide. I only painted the lower half as I was using the sail as a convenient hand hold while I was applying the paint. I will give the upper half a coat when this has dried

 

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I am not sure the MM painting guide is correct as they indicate the red oxide/black hull demarcation is below the rear horizontal dive planes, but reference pics for the BF show it to be considerably higher?

 

cheers,

 

Pappy.

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  • 3 months later...

G'day people,

 

A little more progress on this one.

 

I  have painted the lower hull in red oxide and attempted  a distressed appearance by adding red, yellow and brown to the basic shade

 

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Now for the fun part of masking up in preparation of the application of the boot topping and upper hull demarcation

 

cheers,

 

Pappy

 

Edited by Pappy
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