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Author Topic: Patrol Boat River (PBR MkII) Build  (Read 9030 times)

BigA

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Patrol Boat River (PBR MkII) Build
« on: October 27, 2010, 02:09:59 PM »

Thought I'd log the build of my Deans Marine 1/24 PBR 'kit'. Although I'm about 3/4 through the build, I hope you'll find what I post interesting/useful.

Background research was obtained from the websites of the PBR Forces Veterans Association, Brownwater Navy, a couple of others - the most useful, which I only came across yesterday (!) was Brownwater Enterprises (www.brownwater.net). There are loads of photos of actual PBR's available - also, I used information gleaned from various builds of the Tamiya 1/35 injection-mouded kit.

The reason for so much background research? Aside from me being pernickety about scale appearance, I have to say that the quality of the Deans vac-form kit leaves a lot to be desired (this is a personal opinion - subsequent to buying it, I found a couple of build reviews on-line which are in accord). It's taking ages to build basically because I'm having to re-manufacture a lot of the parts/the majority of components - many of the printed bulkheads didn't fit, many of the cast (resin and white metal) components are poorly moulded; the build instructions have photos missing and even use photos from different kits! I'm used to scratchbuilding, so such problems are merely an annoyance, given the price paid for the kit (95.00).

Initially I thought about power sources, and how these would determine the build and general layout...... I toyed with the idea of installing two water jets, but didn't fancy the associated expense - also, the available hull volume is small, even in 1/24. Then I considered using twin electrical motors - the fit would have been okay, under the well deck (Cornwall Model Boats have some very nice small Graupner motors) but I wasn't happy with the non-scale appearance of twin props (and associated rudders) coming out of the transom, above the water jet outlets. So I reverted back to the single 400-size motor/prop design of the kit - at least when it's on the water (eventually), the prop/rudder won't be visible.

I build a boat stand based on the US flag, using self-adhesive stars and insulation tape, on a painted ply base; this was framed with edging and finished with french polish and wax.

We take the build up at the point where the hull and deck have been joined...... Not described is all the tedious work on bulkhead re-manufacture/sizing/fitting/etc. I had to build a motor mount from plasticard, as the vac-formed kit-supplied item was inadequate. The well deck is in place together with the basic servo/rudder cover (more on this later).

The basic hull/deck/superstructure are okay but require a lot of remedial work...... lots of P38 filling/sanding


You can just about see where I've added plasticard section mounts for the receiver (port), ESC (hull floor) - also made one for for the on/off switch (starboard, not visible)

Hull-deck underside join

More to follow......
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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #1 on: October 27, 2010, 02:14:54 PM »

More filling/sanding on the cabin......

Interior of the cabin showing scratchbuilt everything.....

I made the cabin on a false floor, which doubles up as a forward deck hatch.

More to follow......
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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #2 on: October 27, 2010, 02:22:09 PM »

Although the real MkII PBR's had a clear flat well deck, the design of the kit is such that a box-section is required to hide the servo and tiller arm - difficult to avoid this, given the limited space...... I added some rivetted bracing to this.....

This is how I did the rivets - punch the rear of the plasticard with a blunt-ish panel pin......

Rivets also visible on the armour plating of the rear M2 Browning.....

The hole on the top of the servo cover allows access to the top of the servo - I designed and built a simple mount (just visible in the third picture) that facilitates attachment of the rear gun to the servo - rotation is therefore achieved simultaneously with rudder movement.

More to follow....
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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #3 on: October 27, 2010, 02:41:01 PM »

Mid-deck in place - I had to extend this to ensure complete coverage of the battery access area - the deck is removable and will be held securely with small cleverly-disguised magnets - the side plates can be seen, where the M60 machine guns will be mounted.

Also added hinges to the hatches - there were three hatches on the mid deck - for access to the Jacuzzi drives - hinges were rivetted again.
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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #4 on: October 27, 2010, 02:58:36 PM »

Talking of machine guns......

I didn't like the quality of the M2's (there are three of these - 2 forward, 1 rear) - by the time the mould lines had been filed down, the barrels would become mis-shapen - also, they're quite soft - so I removed them and drilled out holes to accept the correct gauge of stainless wire, cut to size...... brass tube was used at the base of the barrels and heat shrink (or plastic tube) for the muzzle - yet to be made up and added are rear grab handles and crank handles for the two forward (turret-mounted) guns.

The M60's were much better - however I didn't like the white metal mounts supplied - I wanted the guns to be rotatable as well as being moveable up/down - so I made up a couple of mounts using plastic tube and rod, with plasticard 'hinge mounts' being made up for the guns themselves

M60s shown mounted on the side plates.

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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #5 on: October 27, 2010, 03:08:20 PM »

The white metal grab rails are supplied in four sections. I figured on replacing them to avoid filing down mould lines and attempting to join soft white metal together...... Much quicker, stronger, and better-looking, was the one I made up from stainless wire.....

The clamshell vents supplied as white metal were totally wrong - the base was too thick but more importantly were of the wrong shape - I modified them by adding plasticard sections to bring them 'forward' - I filed the thick base down, first, and replaced them with plasticard

The cast resin ammo boxes had defects on them from the moulding process (very thin/air bubbles) - I re-lined them internally with very thin plasticard and filled the outside with Milliput - the (middle) box for the rear M2 required a new lid (made from plasticard)

More to follow.....
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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #6 on: October 27, 2010, 03:16:30 PM »

I'm now working on the forward turret - again, the white metal kit components are woefully inadequate, so these will require scratchbuilding.

Shown here is the basic construction..... The kit requires cutting and bending of quite a thick plasticard section around a thin circular disc - even with heat applied and rolling, there's no way this thick section is going to stay put and maintain the circular shape. Instead, I used two sections of thinner plasticard, rolled to induce curvature, and laminated them together.

The circular shape is maintained - the join line is filled with a sliver of plasticard before being filed/sanded down flush


Well... that's where I am so far..... I'm still working on the turret - it needs to be rotatable (by servo) and bored out to accept a figure. More updates to follow......
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longshanks

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Re: Patrol Boat River (PBR MkII) Build
« Reply #7 on: October 27, 2010, 10:10:05 PM »

Looking good

Keep up the good work  :-))
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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #8 on: November 15, 2010, 12:50:04 PM »

I'm back!

Continuing, as follows:

The front turret design of the kit is very simplistic - I'm therefore detailing this and adding rotational functionality. Here you can see the underside that has been bored out (the gunner sits inside the hull on a hammock that's attached to the sides of the turret) re-modelled using plasticard - the metal rod locates into a bush that I've aligned and cemented into place inside the hull - the side of the turret acts as an upper bush - an actuating rod from the servo connects to the plasticard horn that protrudes - testing showed about 100deg of rotation is possible.

I made up a small servo tray from plasticard - the servo is of the 'micro' variety - only cost about 5......

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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #9 on: November 15, 2010, 12:56:00 PM »

The radar assembly, now......

On the left, you can see the soft white metal kit fitting. This is under-scale, and lacks some of the supporting framework that is required. So I scratched-up a more scale-like assembly using plasticard and rod.... I added reflector plates - these are located below the main radar dome.


Here we see the (almost) completed assembly mounted on the cabin - the radar post is held in place on the underside of the cabin roof using a locating tube (epoxied in place). Care was taken to ensure that the assembly was vertical, bearing in mind the cabin roof is sloping forward.

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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #10 on: November 15, 2010, 01:03:14 PM »

The aerial posts, now...... The kit units are just about acceptable, with the exception that they are designed to be mounted on a horizontal surface - the problem is, the cabin roof is sloping, so the aerials would otherwise be pointing forward rather than vertical! Easily rectified by thickening up the base with plasticard......

...... cutting/sanding down to a wedge shape......

...... and mounted on the roof - a bit of filler is required to blend the bases in and cover the plasticard-to-metal join. The top of each basethen needs to be drilled out to accept the aerial (metal or plastic rod).

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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #11 on: November 15, 2010, 01:08:34 PM »

Still on the ancilliaries......

Two of the white-metal lift hooks were overly-long - the real ones should be smaller. Easily rectified by cutting and filing...



The white-metal siren (left hand side) is poorly-cast and bares no resemblance to the real thing... Here I'm making a new one using plastic strip and an item from the spares box (I can't remember what it was saved from!)......

...... a bit of cutting/detailing/addition of a mounting post and this is what you end up with......

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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #12 on: November 15, 2010, 01:14:14 PM »

The modified clamshell vents have now been opened up...

The white-metal anchor and resin lifebelts had significant surface defects - probably caused by the presence of  air-bubbles during the moulding process - these were rectified with Milliput and sanding...... The kit-supplied rudder consists of a white metal slab cast over a metal rod - the rod actually poked through the surface of the rudder in one place...... I rectified this by skinning the white metal with plasticard and filling/profiling to a more realistic shape.

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Dreadstar

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Re: Patrol Boat River (PBR MkII) Build
« Reply #13 on: November 15, 2010, 04:24:24 PM »

Looking good BigA,keep up the good work. :-))
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RaaArtyGunner

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Re: Patrol Boat River (PBR MkII) Build
« Reply #14 on: November 16, 2010, 01:00:29 AM »

The white metal grab rails are supplied in four sections. I figured on replacing them to avoid filing down mould lines and attempting to join soft white metal together...... Much quicker, stronger, and better-looking, was the one I made up from stainless wire.....



Big A,

Judging by the images agree that the grab rails are now better looking.

Looking good  :-)) :-)) :-))
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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #15 on: November 18, 2010, 12:51:16 PM »

Contentious one, this. Many photos of real MkII PBR's 'in the field' do not show exhaust outlets. There are, however, two hulls under restoration where the exhausts are evident as well as the outlet mufflers mounted on the stern (http://www.brownwater.net/Project/Hull2.asp). These were 'missed' by Tamiya in the 1/35 injection-moulded kit. I decided to include them on my build.

I made the exhausts from two 5mm diameter plastic straws - the ones with the corrugated bend section - a piece of plasticard is attached to one end to facilitate mounting to the bulkhead...... If you double click on the photo, the whole assembly can be seen

The exhausts are normally covered by curved GRP panels - I'm depicting them open, however, as it looks more interesting.

The stern has to be drilled to take the exhaust outlets - a couple of plasticard rings were made for the outlets, just like the real thing..... Also visible at the centre of the stern is a cut-out/support mount I made for the rear light - this is not mentioned in the Deans Marine instructions - a 3mm LED will suffice for the light......


I don't think I'll bother with the mufflers - they weren't used all the time, anyway.
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Boulderboater

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Re: Patrol Boat River (PBR MkII) Build
« Reply #16 on: November 29, 2010, 04:44:14 PM »

I thought on the PBR's the mufflers themselves, not just the exhausts, were inboard behind the curved side panels - isn't that why they are that shape?
The PT boats had the mufflers outside on the transom?
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RaaArtyGunner

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Re: Patrol Boat River (PBR MkII) Build
« Reply #17 on: November 30, 2010, 01:27:58 AM »


I made the exhausts from two 5mm diameter plastic straws - the ones with the corrugated bend section - a piece of plasticard is attached to one end to facilitate mounting to the bulkhead...... If you double click on the photo, the whole assembly can be seen

Neat idea  :-)) :-))
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derekwarner

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Re: Patrol Boat River (PBR MkII) Build
« Reply #18 on: November 30, 2010, 04:28:36 AM »

 :-))...absolutely brilliant BigA....... O0 ...& I thought these were only for keeping my grandchildren happy  {-) %% ....Derek
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Derek Warner

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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #19 on: December 01, 2010, 11:30:20 AM »

I thought on the PBR's the mufflers themselves, not just the exhausts, were inboard behind the curved side panels - isn't that why they are that shape?
The PT boats had the mufflers outside on the transom?


The ones I've seen show the mufflers outside, on the transom, just like PT boats use...... Here's a pick of the exhaust outlet from Brownwater.net:




I can't find the one of the muffler at the moment......
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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #20 on: December 01, 2010, 11:50:05 AM »

Here we go......

The mufflers themselves are in the well deck, under cover...


View from the rear showing the exhaust outlet covers......

View showing two PBR's without covers in place...

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BigA

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Re: Patrol Boat River (PBR MkII) Build
« Reply #21 on: December 01, 2010, 11:59:33 AM »

I appear to have mixed up my terminology when discussing 'mufflers' and 'covers' - it's this bloomin' 'kit'  >>:-( Loads of unexpected work/rectifications/modifications required.

Rant over. ;)
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