PBR Mark 1 River Patrol Boat by Thistle17 - FINISHED - Scale 1:6 - Model Shipwright Guild WNY

[Thistle17]

I am pushing to get the hull primed this weekend as the weather is going to be in the mid 60s and I can't spray in the basement. As a result I could not let this setback prevent me from that goal. The rub rail I have found is about 3/8 inch wide in scale (1:6 maybe slightly less). It has a slight taper across the width inboard to outboard. Using bass wood I built a shooting board and tried to add the taper but I quickly found that I was having trouble getting a uniform tapered edge not to mention tearout. I then thought of a more obvious way.

 

On the Byrnes saw I taped a 1/32 inch strip to the base of the saw fence. At this point the rub rail has been purposedly ripped to 1 inch width. Using my shop built ripping guide to keep the stock snug to the fence base and the top edge snug against the fence top (with my push stick) I managed to get a consistent taper These will be ripped to width and given some final detail sanding and attached to the hull/

 

I anticipate soaking, maybe steaming these strips at the bow to form to the bulbous bow shape. I may even have to segment the rail to get the desired conformance. I now think I have a fair chance of making the milestone.

 

Jim if you are listening I wish there was a tilting arbor retro for this saw.

 

Joe

Edited November 1, 2020 by Thistle17

[Thistle17]

We were gifted with a record setting streak of warm weather here along Lake Ontario these past 7 days. And so were able to complete some last minute details prior to priming. To start with I finally decided to wet sand the hull to fair the Nitro Stan glazing compound. I had hesitated earlier as there was still a good deal of bare wood showing and it is a messy process as you auto body folk well know. It was left to dry for 2 days.

 

Once that was done the rub rails were added up to the bow area. That was truncated because I have yet to master the "fair in" of the bow and the rub rail and the bow rub rail has to be specialy cut to fit the bow area as segmented rub rail was not going to traverse the bow. You may also see that a hull detail was added up to that point. It is an artifact, I believe, of the original hull layup as these hulls were intended for both pleasure and fishing craft. It is a simple 1/32" relief under the rub rail that follows closely to the waterline.

 

One last detail was added and that was the trail board attached to the transom. On Mark II versions of the hull this was built directly into the transom.

 

The day this was painted the air was relatively still but the relative humidity was quite low. As a result we were unable to get a full wet coat application on the primed hull. I chose automotive primer for the task so that has added to post priming tasks of a light wet sanding with 400 paper. The topside area is still to be worked to simulate the gullets of a fiberglass molded topsides so that is yet to be treated. Otherwise I am happy to report, in spite of all the applications of fill and glazing compound, the hull ia quite presentable from a fairness standpoint. I am sure the wet sanding will reveal some 'holidays' but for the moment we are go to press on.

 

Joe

 

PS: That sheet behind the model is a weakly veiled attempt to hide a messy counter area more than a backdrop cloth. Who said I had to be neat!

[Roger Pellett]

Joe,

 

Nice work.  Your Rust Oleum spray can really highlights the model’s impressive size.

 

 

[Thistle17]

Because of the Covid restrictions ( we are approaching an Orange rating for our county, after having the best state infection rating pre Thanksgiving) our work has slowed dramactically. Yesterday just a bit more advancement with the final fit of the gun tub into the cavity forward of the pilot station. Lots of clean up and fairing left to do topsides as previously stated. Nearly the last thing to do on the gun tub is form and fit the gun carriage supports. A member of our group has volunteered to convert a tub side profile image to a measured drawing for that purpose.

Joe

 

[Thistle17]

Conditions have not improved much in the Finger Lakes Region as far as the infection rate goes. People just let their guard down and we still have an infection rate of 9%. Vaccinations for our 1B population has started but the supply chain is faltering. i suspect even with increased supply there will be a bow wave as first time recipients compete with 2nd round recipients. All part of the Covid Crazies!

 

But I digress. I voluntered to turn the support system for the forward gun tub trays, as I have the lathe. I first tried making the system in one piece out of 1/2 delrin rod. It did not go well. In part because I am not a highly skilled turner and secondly when the turning got down to the 3/16 diameter the rod just did not have sufficient axial stiffness. So I turned to the old standby and made it out of brass. Actually the main body is 1/4" tubing with an ID that allowed yet another piece of tubing to slide neatly inside. That in turn very nicely accomadated a 3/16 inch rod which was end drilled to take the 1/16 rod. At present the 1/16 rod is quite long to aid in alignment of the whole assembly when it is installed on the gun tub support bracketry.

 

The assembly is not soldered as I have to experiment with brass blackening and its interaction with solder flux. I suspect the answer will be "not well", in which case the assembly will be glued.

Joe

[Thistle17]

I know i have said this before but the gun tub is a project in itself making progress measured. Since the last posting, Jim, has made further advancement by assembly  (albeit dry) of the gun carriage suspension components and has started some work of the gun locking system and other internal details. I think he is doing himself proud. Would you agree?

 

Please note the guns are not mounted in their respective carriages but lay along side for perspective.

Joe

[Blackreed]

This is really cool.

 

The scale is awesome, you should have no problems getting people, guns, mortars whatever you could want in this scale.

the turret you have chosen feeds the 50 cals from the center, the charging handles are opposite the feed side.

It would be really interesting to hear how they loaded them from your boat operator. And how they suppressed fire while reloading.

The rounds are sensitive to the elements, so were there ammo cans that allowed them to place 200 rounds in for each gun?

I’m sure there was a spotlight of some kind on that turret, I would assume that light would have been mounted above the head of the gunner, this would have blinded the enemy and also caused the enemy fire to be directed at the light, estimating that the average fire fight was 100 meters would have caused the small arms fire to climb over the boat, or at least the head of the gunner.

 

 I hope you don’t mind if I follow along with your build.

 

[Roger Pellett]

All of you guys are doing a great job!

[Thistle17]

Thank you both for your comments. Blackreed your comments suggest familiarity with this type configuration. Although, Jim our modeler, is ex Navy, his duty was with nuclear power systems. That has left us with many questions of just how these weapons were loaded/reloaded, where the casings ended up and as you point out the spot light was just asking for it to be shot out.

Edited February 21, 2021 by Thistle17

[alross2]

Just stumbled onto this thread.  That's a MK56 gun mount, which I've not seen mounted on a MK1.  I have the NAVORD manual for it in PDF format.   It contains detailed drawings of the mount and I can upload it for you if this format can handle PDFs.

[Blackreed]

Thank you for that information alross, that really was some enlightenment, and very interesting, I still have a lot of questions, but I’m naturally curious.

I served as a weapons expert too, I’ve never studied anything like this, so it raised a lot of questions, and seeing the different variants is awesome.

 I was on a navy ship one time, I could not get over how clean it was.

 

Thistle keep up the good work.

[Thistle17]

I googled Browning 50 caliber machine guns and came across some videos that not only were impressive but made me pause as to how these guns, in a tub, functioned without burdening the user.

 

Joe

[alross2]

Some of the MK56 manual illustrations.

[Thistle17]

So revealing! Thank you.

Joe

[Thistle17]

Amazing, just amazing! alross2 has sent us a response and access to the proper design drawings for the MK1 gun tub . The plot thickens a  bit as he responds;

 

NAVORD 3741 attached.  I'm wondering whether the boat at the museum has been monkeyed with, as I've never seen a MK56 mount on a MK1.  The MK56 was fitted to the PBR MK2 and the PCF MK2, while both the MK1 versions used a modification of the WWII PT mount, the MK17.  In the latter, the gunner was behind the weapons, as opposed to being between them in the MK56.

 

So we find some modifications may be in order. School is still out on this.

 

Thank you one and all!!!!

 

Joe

[alross2]

In talking with a friend who was a gunners mate during Nam, I discovered that a few MK1s were retrofitted with the MK56, but it was not common practice.  He also said that 105 was not one of them.  As an aside, the manual for the PBR MK2 indicates that they were painted Marine Green 23, supposedly FS34052.

 

This is the standard PBR MK1 mount and the MK17 mount from which it was derived.

 

Edited February 27, 2021 by alross2

[Blackreed]

There’s no doubt that the PBR1 came with the MK17 turret, however looking at it clearly shows it is an anti aircraft set up, not to mention the ballistic armor is to the sides. Most likely this would have been retrofitted, possibly before any Canadian variants of this hit Vietnam.

Those ballistic panels would have made an easy target for a sniper, not only would this have directed his fire right into the chest of the gunner it would have left the sniper to have simply stayed put, no one else on the boat would have had sight or line of fire on him.

The MK56 that you have pictured there is an anti personal configuration. Having the ballistic plate with the sight on it directly in front of the gunner would have protected him. This set up would have done heavy damage to not only the personal but also to any cover they may be using.

 

Another point here would be that to engage the gunner from an elevated position like a sniper would, would leave his round “driving” downward, ie when you shoot down the round drops, that’s why the armor was moved to the center.

 

The most critical point here would be the shock wave the M2 as well as all 50. Cals have. By separating the guns like this if the gunner had engaged personal with the sight the 2 rounds passing on either side would still have ripped the person apart, this is why the guns were separated.

 

One other thing I learned was that these boats are fiberglass. If this is true, the most important thing would have been the boats speed. My guess is that these “gun ships” would have made for excellent cover, as well as an effective delivery system for the Marines or special forces.

 

 

[NavRetSmith]

On 6/27/2017 at 3:18 PM, Jim O'Connell said:

As a retired Naval Officer who worked in the ship design business, I was able to track down the division of the Naval Sea Systems Command that is responsible for small combatants and boats. The Combatants and Boat division (NAVSEA 05D) did the design of the PBR 31, in house (Navy), and they have complete sets of of both the Navy's contract drawings and as well as the builder's detailed drawings. My contact has initiated a "Request for Approval to Release" drawings to the general public for a number of drawings that he thinks will be of use to us.  This is a necessary procedure to ensure that there is no classified or proprietary information on the drawings that would preclude their release.  This process might take a couple of weeks.  When approval is received I will be in contact with the division's librarian to arrange to get copies sent to us (Model Shipwright Guild of Western New York).

 

[NavRetSmith]

From NavRetSmith:

I just registered and I have a MK1 PBR  Boat # 120 that I am restoring and has no forward Gun Tub. I was thinking it should be a MK56 but after reading your posts it looks like it should be a MK17.  I was on PBR in 68/69 but dont remember details that much. You also said you are getting drawings for the MK1 and could you send me copies to my email? Thoes would be of great help.

Thanks and I enjoy reviewing your posts.

 

Gary Smith

husker5039@gmail.com

[Thistle17]

I have been so busy with other tasks, some apart from modeling, that I have neglected checking in here.

 

Our gun tub is being modeled by one of our members, a retired Navy Captain, who was responsible for propulsion systems on neuclear craft. as such he has incredible talent for detail and has been using references of a detailed nature. I have seen the results of his recent work (since the Covid relaxation of restrictions) and it is outstanding. The Patriots Point information we had has led us a bit astray as that now appears to us as a creation out of need and lack of authentic elements. Please do not interpret that as a lack of gratitude of their support.

 

If you PM me I will put you in touch with our member and he should/would be happy to help you out.

 

Joe

[Thistle17]

Here it is 3 months later! Where does the time go?

 

I wanted to show you the advancement of the forward Gun Tub that has been made since Jim began the build out of this very complicated sub system. The manual from NAVORD provided by ALROSS has been a break through event for us. We are so grateful.

 

And I must publically compliment Jim on his incredible rendition of the 1:6 scale model of the gun tub. I knew from the outset he was the one to execute this unit and I knew it would be done with care and accuracy but my jaw dropped when I finally saw it all assembled and painted correctly. You will note the flash guards now mounted on the barrells. In addition, though hard to observe, he has detailed the innards with the fire control panel, charger system and rotational mechanism. The only thing he has left off and to come is the search light and 50 cal bandoliers.

 

Joe

Edited September 29, 2021 by Thistle17

[druxey]

Too bad the paint is so dark we can't see the fine details! First rate lovely work, though.

[Thistle17]

David its that Marine Green almost green/black. I will see if we can improve on the situation of our photography.

Joe

Edited September 29, 2021 by Thistle17

[Roger Pellett]

I respectfully disagree with David.  I like the paint job.  I suggest that you leave it as is.

 

Roger

[mtaylor]

Beautiful, if .50's can be called "beautiful".   

[druxey]

Roger: I think Joe meant adjusting the photography/lighting, not altering the fine paint job! I certainly did not wish to imply that the paint be changed.

[Roger Pellett]

David,

 

As my photography skills are strictly point and shoot, that possibility never occurred to me!

 

Roger

[Thistle17]

To say this gun tub deserves a good home is an understatement. One of the most troublesome parts of this project has been a hull that meets the replication requirements and is worthy of such a fine sub system as the gun tub. If one recalls the hulls were reworked products of United Boat Works of Bellingham Washington. As such hull drawings were minimal so we had to replicate via what we had including photos. Patriots Point photos have been the most beneficial. As we now are preparing to ready the hull for all the topsides detail such as the helm build out, the stern gun platform, all the topsides armor shielding and the canopy metal work we had to get one last hull detail right.

 

The bow flair has plagued us from the get go. It just wasn't right compared to the photos supplied. So to tackle the problem the bow rub rail was built out in laminated form from about the chine entry to the bow with water soaked bass wood bent and pinned to shape around the bow port and starboard. This built a "shelf" to which more Rage Easy Sand body filler was added to "bulk up" the area. At this point we needed a product we could easily shape and sand to the correct contour. We discovered yet another Evercoat product called Metal Glaze Ultra that is advertised as applicable over painted surfaces that have been roughed up. It has the same open time as other Evercoat products (about 5 minutes) but this product has a consistency of thick mayonaise. Using a rubber applicator we were able to fair the surface to a near perfect contour.  Sanding and checking with the guage to the left periodically yielded the desired result.

 

Joe

Edited October 2, 2021 by Thistle17

[Thistle17]

We cannot account for the lost days and time during the Covid isolation as I am sure you will agree. As far as the PBR is concerned we have been working on her albeit haltingly. Here is a recent photo of the model coming together in April for a dry fit of masts, gun turret, helm (not shown) and rear 50 caliber tripod mount gun. The hull still needs some refining but we are getting close to a full paint job of the basic unit. Lots of fittings and details to add but we are getting there.

Joe

[Roger Pellett]

Very nice Joe!