Scratch build Soviet Project 661 Anchar "Papa" Class SSGN K-222 1/120 Scale.

[gantu]

[JHapprich]

Hi David! Great progress on the model, but there is something i recognized taking a closer look at the stern horizontal planes and stabelizers. Correct me if im wrong. There is that one beautiful shot in your first post showing then-K-162 under construction and the stabelizers, planes and the small aft flap do NOT line up with the middle/centre of the hull but are aligned below. This is a very common design of soviet submarines of the 2nd generation, e.g. the plane/shaft configuration of the Yankee and the following Delta-class. Practical issue, building the model you would not have to design a complicated control mechanism for those planes but might use a simple straight rod. No need to build around the propeller shaft. Something i had to learn during construction of my Silent Hunter 3d models and my Delta II SSBN.

Jörg

Correction: the one small flap seems to be installed in the middle. The main planes may need to be located lower on the model.

[He Who Shall Not Be Named]

Your work improves with each new project, Dave. Your PAPPA is shaping up nicely.

David

[Davidh]

Hello all,

It's been a busy week. We are about half way through our extension of the house and adding a new kitchen. I'm over cooking dinner in the laundry. Anyway I did manage to get a little bit of work done on the Papa.


I have been eyeballing the Papa's rear end. (That could sound dodgy..) It looks right as I cant see any areas of glaring un-symmetry. I have made a couple of templates that are designed to take one side and impose it one the other in order to see where there are divergencies. You simply take the profile then flip it. I cut one out of cardboard after going around the starboard side rear profile. Then cut it out and used it on the other side. I couldn't see much of a difference. The only major area needing work would seem to be around the horizontal plane fillet profile, making sure that the curve of the trailing edge lines up on both sides.






I have also had to shave just a small amount off the trailing edge fillet of the top vertical rudder. You can see this in the above photo where there is a bit of Renshape pink exposed. This will allow the rudder to turn more freely and make sure that the rudder hinge mechanism is free. The other big area to consider is in making sure that the booms are of consistent radius on both sides at any given point. I have never had to worry about this before as I have only built single screw boats in the past. Brave new world...

I designed and printed off the middle horizontal plane. This little part has almost been in jeopardy of being ignored. I had almost forgotten this little dude. The printed out part looked to be too thin. So I got hold of some Renshape and sanded down a little piece to the correct profile to match the stern plane. I needed to make sure that the sides were angled in at the same degree on either side. I also had to make sure that the thickness of the profile did not exceed the depth of the trailing edge of the hull that this movable plane hinges into.

I then drilled a hole down the centre for a brass rod to fit through. Finally I added some filler and then sanded back gradually to get a consistent surface and profile. There was also an issue where the drill actually came out the side at one end. I then added some filler here as well and carefully re-drilled the hole. The edges of the surface butt up against a slightly curved surface of the booms. This creates a slight pinching at the neutral position. The last photo shows where I have filed around the inside surface so that the vertical surface is constant for the hinged surface end to move up and down with a constant distance between it and the boom.

David H

[Davidh]

Hello all,

After making the two mould halves for the rudder parts I then poured some polyurethane resin and in no time had some really good reproductions of the required parts.

The Papa has an escape hatch towards the stern and another hatch of wider diameter not far forward of it. She has pretty much the same arrangement up the front of the boat. As a result I had to then reproduce the brass escape hatch just like the one that I made for the rear end. So Once again turned a piece of brass to the same diameter and then parted it off. Once that was done I marked out the are where It would be located and then used the Dremel to cut out the surface. From here I would then mix up some filler and then press the brass piece into the soft filler. Once hardened I would simply sand around the edges and bring the surface to level with the rim of the escape hatch.

Once this was done I then located the other hatch position, marked by a larger white ring. This hatch marking looks slightly raised so like the one down the back I took a washer of the right size and thickness and glued it down in position. I then realised that this brass washer wasn't right. After looking around I found that the red washers that you get from plumbing jobs are just the right size and thickness. I sanded down the surface and found that these glued down really well. I then replaced the one at the stern too.






I did a bit more searching and after looking at lots of Russian sites and guessing my way around, You look at anything that looks like it says "npoekt 661" as this is as close as my Russian gets to 'project 661.'
I got lucky and found a couple more pics that I had not seen before. The one I really like is the one showing the fin as the boat is diving. There is also a pic of a Papa model from a Russian museum...

[Davidh]

Hello all,


Pulled a couple of parts from the moulds made for the horizontal planes. One of them had air bubbles at the top. The air bubble obviously didnt find the vent that was right near it. I may
have to cut another vent just near it. Other than that the vents work well and the parts that I have pulled look really good.

I have barely touched the hull, most of the scribing is done and its really some alignment at the back end. So I then started the process all over again by arranging the next set of parts to be encased in silicon temporarily to make the moulds that will cast these parts. I spent a bit of time checking the parts before setting them down on a base. I gave them further fine sanding down, wet and dry. I went over some of them with small smears of filler just to get the smallest undulations out of them. Sanding back then a spray of wet and dry. How you arrange the parts is crucial. You really have to think about how the resin is going to flow and how the air will escape. You get this right and your mould design should work.

So I have taken the top and bottom rudders and their fixed posts. ( the front of the rudder). As can be seen from the first photo I have taken some MDF and simply traced the outline of the parts, pouring sprues, and vents. The areas around will them be filled up with shallow drill holes to make the register points. Once I have done this I then drill out the register holes. I have also drilled inside the area that each part sits in and then get the Dremel and grind out the area for the part to sit in. I grind out a curve in the base to suit the profile of the part. I want the part sitting so its half sitting under the surface of the base. I then go around the perimeter with clay to seal. Even withe the best intentions I still find that some silicon makes its way under the part.

Then cut out the balsa that will make up the Sprue super glue it to the base. I then take paper clips, cut them and fit them following the profile that I had drawn around the register holes. Super glued to the base. Once this was done I then screwed the four walls onto the base.

Finally more clay around the section where the balsa sprue sits to shape the funnel at the top of the mould where the pour occurs. Once this is done, then check the sides for any gaps where silicon may leak. I will often use more clay wedged in the sides. Then I put some tape along the bottom just as extra insurance..

[The Boattrainman]

We're losing touch with the Apollo missions as the pioneers pass away, man's greatest acheivement in my view, we've been going backwards ever since, and at the rate we are killing the planet (pollution, over population, climate change, decrease in bio-diversity etc.etc.), it looks increasing like the moon will have been our only excusion to another world. The whole Mars idea is not a runner at the moment, and time is not on our side...........!

Rob

[trout]

yeah, unfortunately many of the space frontiersmen that I grew up watching are aging and succumbing to the final frontier. Whether I am in denial or not, they seem too young to be passing away. I used to record some of the Apollo mission launches on a tape recorder. Loved the sound of the engine roar. I barely remember the Mercury mission, but each revision (Mercury, Gemini, Apollo) brought new excitement and dreams and models to build. I had the Gemini model that had optional landing skids on it (a thought of alternate landing,inspired probably by the Russian landings, other than splashing in the ocean).

[Davidh]

It seems like not too long ago I wrote one of these for one of my hero’s. This has come too soon.

farewel Alan Lavern Bean- Apollo 12, Skylab 3.

Also a fantastic artist.

[Davidh]

Hello all,

So after creating the one side I then mixed up some RTV silicon. For each design that I do, I buy a new silicon pigment colour to do the moulds in so that I can easily recognise which kit
they are from. I have decided that the colour would be a beige skin colour. I decided to mix this by using some orange, green and Blue from the pigments used on previous boats. Mixed together all these
colours end up making a nice tan colour.

Checking around the side of the mould walls I pushed some clay into gaps in the walls just to ensure no leakage. Once this is done it is time to pour the silicon. I usually pour the silicon at night, just before I go to bed and come and look at it the next morning. Usually by then it is rigid and stiff and ready to pull off the base. Once pulled off I simply had to clean out the mould part. There was left over clay from the funnel tops and pull the wires out from the mould. I also go around the outside of the mould and trim off excess silicon. I take a Stanley knife and cut grooves around the vents just to give more passage for air to escape.

Once that is done I simply repeat the process except that I use the base of the already made mould part to mount the parts and recreate the mould ready for the other side. Firstly I take some lanolin and rub it all over the mould just so that the new silicon wont stick to the old. I took the balsa strips and re-laid them in the channels that will serve as the sprues. Extra lanolin gets wiped into the cavities created by the wires that act as the vent channels. Place the parts back in the mould with the brass inserts in the holes where needed. Re-screw the outer walls on the mould and add red clay to re-create the other half of the funnels at the top of the sprues.

Once this was all completed I simply poured more silicon and waited till it had hardened the next day. Once hardened simply pull apart and pull the masters out. No longer needed. Clean up the mould and you're almost ready to start pouring urethane. Bottom rightcs show the completed moulds and also some of the first parts to be pulled from them...

David H

[Davidh]

Hello all,


I have got to a point where I can freeze the design of the appendages and control surfaces. They designs are pretty much locked in a so now the process of making the silicon moulds
starts. I am starting off with the horizontal stern planes. the fixed plane and the movable one. Once again I have gone down the tried and true method that works for me anyway and that
is the box method with sprues and wire vents glued to the surface.

Firstly I outline the profile of the parts, making sure that they are well below the top of the mould. The longer the sprue,the more gravity can pull down extra resin when the Bubbles collapse.
I then draw the lines around the side where I intent to put the vent lines going up to the top and draw a wide funnel section at the top. This allows me to pour excess if need be and allow that head of resin as mentioned before slowly pull down as gravity and pressure replace bubbles. I then drill holes around the sides as these are the register points for the two halves.

Once done I then start cutting out the shape of the part so that it will sit about half way up with the flat surface of the mould. I like the parts sightly 'sunken'. Once this has been done with the
Dremel tool I then push brass inserts through the holes. Once the parts are in place I can then go around the surfaces with modelling clay and get the edges around the parts, smooth.

Then I cut out and lay down thin wire, Ive looked all over the house for paperclips and couldn't find any so I found some thin brass wire and cut out small strips and laid them down in between the register holes. Running from areas I through experience have taught me have been areas where bubbles can accumulate up to the top. This will mould a nice neat channel into one side of the mould. Then I will replace these on the other side, come time to create that.

Finally I then cut out and add Balsa strip to the top of each of the parts and create a funnel at the top of the mould. This will be the sprue for pouring the polyurethane resin.

Meanwhile I have taken rectangular blocks and created the walls around the outside. I use two countersunk screws per block and make sure that the edges are sealed.

So that's one side done.....

David H

[Slats]

Was a nice surprise coming back in here... probably your best yet u/c...and I have identified a boat u/c here on SDF that I have always wanted in 72nd scale.

[Davidh]

Thanks John,

Good to to hear from you. Slowed down a bit of late. Renovations , a Resolution retool and too much school/government paperwork at work.

dave

[Slats]

Sorry I haven't been around mate - liking this build. Well done. John

[Davidh]

Hello all,


After pouring the silicon for the first half of the mould, I then pulled the propeller out of the mould. As mentioned earlier this was the simple part of the mould that recreates the front end of the part. The second part of the mould would be more complex as I then had to create the pouring channel, the air vents and the insert that recreates the thread of the shaft.

I have found that the best way to channel the air out of the mould is to create vents that 'ride' up the ridge or upper edge of the propeller blade and then through the silicon to the upper surface. To do this I cut out an old plastic 2 litre milk bottle and then cut some small little profiles that I glue up along this edge. These profiles are shaped find of like and upside down letter "T'. The arms have a subtle curve on them to gradually allow the air , as it moves upwards to funnel its way to the hole and then out of the mould. The photos probably don't do it justice.

I then carefully glue a small brass shaft up one side of the bottom of the propeller shaft. This is where the resin will pour down into the mould. At the top of this I place a rounded piece of clay that will act as a funnel inside the mould. The idea being to pour the silicon up to level with the top of the clay. I also screwed the 2mm thread in the form of a 2mm bolt . This bolt will create the thread needed in the part once moulded. The bolt is pushed down into the mould and protrudes just slightly into the cavity, creating the thread shaped hole that will allow a shaft to be inserted and tightened.

Once this is all done the lower mould is rubbed vigorously with a thin layer of lanolin and then the propeller is placed back in. Once that's done the whole unit is slid down inside the acrylic cylinder that makes the walls of the mould. I silicon along the bottom of the cylinder to the wood base. I then mixed up a batch of silicon and poured it into the mould.













The last photos show the top mould cured and with the acrylic tube taken off. You can see the plastic vents sticking up, the inserted bolt and the area that makes a funnel once the clay has been moved off the sprue pipe.


David H