Scratch Build Soviet Project 667 BDRM Delta IV SSBN K-18 "Karelia" Scale 1/140

[Davidh]

Hello Jorg,

Thanks mate, I do appreciate the feedback. No one else is. I keep all the masters, because you never know if you may need to remould from them again. I found this was the case with the Resolution class as I remoulded its hull 3 times to try and get right. It was by far the hardest boat I have ever done in terms of subtle detail and the complete lack of information on it. Steve Pryce who is doing Repulse over in the UK has said the same thing. I had the opportunity back in '17 to visit him in Birmingham and see his master. It is fantastic..
The masters take a bit of a beating. Sometimes I have to yank them out of the moulds and Papa's broke in two! I'll send some picks of the carnage...

Anyway back to 667.

So with the overall shape of the stern looking pretty good. it meant a lot of sanding, sanding, sanding. Filling in undulations and re sanding. In the meantime just checking that the two booms are symmetrical, identical and angle out the same amount of degrees as needed. Making sure that when you look from the side that you get the same profile running down the stern of the boat. After a good session of sanding I would re-establish the overall lines of the wood blocks. These give really good profile lines that once again give you a good idea of the overall symmetry and surface of the hull. If these hull cross sections deviate too much from each other, you either have to add more filler or sand more filler. Looking along the back end I am amazed at how even and consistent the overall shape is this early..

























So as can be seen from the last picture I have also been busy on the small parts printing side of things. I have probably printed about 2-3 versions of most parts by now. The printer I am using is doing a reasonable job however It has been difficult to get the sizing exactly right and to some extent I have had to guess until hit upon the right size. It has also allowed me to prototype parts, check fit and durability of things such as hinges and the like them re-design and then re-print. I have also cut out the profiles for the missile deck. This will be built mainly out of plywood and then strips fo timber. It will then on the top be given a strip of Ren shape that will hold all the detail of the missile deck doors.

The top rudder section will actually be slightly reduced in size from the one seen here. It I will not be printing out the base but will do this in Renshape. The actual parts will slot in as is my custom to a recess that will feature on the top surface of the raised profile fillet that will appear on the upper stern hull between the booms.




I couldn't resist getting the basic mock up happening as rough as it is. It gives an idea of the size and overall proportion of this boat. It certainly has plenty of character. As mentioned previously the screws need a lot of work, you can still see layers on them and some small bits of filler that will need to be smoothed off. I drilled and placed some 4mm threaded rod in the two stern booms to get an idea of how the screws will look. I'm pretty happy so far. You need some really fine tools to get into the crevices and irregular curves in these blades. Hours of work ahead...








The next area that I decided to look at was the stern planes. I have invested a fair amount of energy designing and redesigning the stern planes and have found some discrepancies between them. For such a large boat they are really quite small, however this seems to be a very Russian thing...


Anyway enough for now, I think that I have scared off HWSNBN...
Please feel free to comment and give advice. Always interested to know what people think...

David h

[JHapprich]

Nighty mice done, david.does the rudder represent the final product or is it just a mockup? Cannot see a hole for the axis. By the way, what do you do with your master models after finishing a kit? Do you put them on a shelf or so?
Jörg

[Davidh]

Hello all,.

Jorg, the prop blades were made from a single blade that I spent a couple of hours perfecting. These were done vertice by vertice and as the shape built up I would extrude and twist the mesh to create the shape. It was quite tricky and took a couple of go's to get right, however I am quite happy with the result and the blade are a reasonable thickness.

The next major step was to create the twin booms that extend out the stern of the 667 BDRM and differentiate it from all the earlier Deltas and Yankees. The wedge shape created by the stern reducing in thickness top and bottom has come along well. There were a few inconsistencies with the side radius's. The outer surface of the hull as it tapers back is almost straight. (If you look at a top view, and run a ruler down the side of the stern hull at it meets the horizontal planes it is almost totally straight.

The stern booms would be turned up on the lathe. Once again consistency and symmetry is something you have to be aware of the whole time. I spent a fair bit of time looking at how I would join these booms to the stern "wedge". As far as I could see there were two options. Either I could cut a "V' shaped cut into the back of the boom and have it slot into the wedge thus continuing the shape of the stern , or the second would involve cutting a vertical cut down into the wedge and then tapering off some material on the side of the two booms. I decided on the second option as I believed that it would give me a few more alignment options and would allow me to have a further means of checking the profile of the wedge by making a sectional cut through it. This would give me a brief opportunity to check any inconsistencies and the overall curve of the very rear end.




I ended up turning two sets of booms. The diameters along the length of the boom needed to remain constant no matter how many I did, however I wanted to determine the best point along the length of the boom where the radius would best suit assimilation into the rest of the stern.Where was the optimum point of transition occurring between the boom and the sides of the hull. The change in diameter of the booms also meant that there would be a change in angle of the boom as it widened the taper would increase. I used a set of outside calipers and concentric lines often redrawn over the sanded or cut sections to check for consistent tapering and that the diameters were right where they needed to be. This tapering caused an issue as the side of the hull transition as mentioned before needed to be pretty much straight. This would require cutting along the booms to maintain that profile. To some extent this could be negated by the fact that the booms would be canted outward with the intersecting center line occurring just in front of the rudder.









The side of the booms that were shaved flat can clearly be seen in these photo's. This was to maintain the almost straight edge of the hull as it heads back to the extreme end. At the same time I had to be mind full of the need to can the booms outwards. To do this I shaved off material on the inside of the booms and at more of an angle to allow the cant to be consistent and true. The careful transition between the curves of the boom as they meet with the wedge of the rear hull would require careful work with filler and sanding.



To install the boom I drilled a small hole along the center line of each boom and and drilled a corresponding hole where needed along the inner surface of the cut into the wedge.
This would allow for a good means of checking alignment especially making sure that both booms were aligned vertically and not tiled up or down to the center line of the wedge.
I just used self tappers.

As you can see there is a pinch where the boom meets the stern hull. This needs to be almost straight, that would eventually need some filer and sanding back. To do this it took one of my steel rules and placed some packing tape along the edge. I mixed up some filler and placed it on the low areas. I then angled the rule and 'rolled' it across the surface pushing the filler underneath and into the low areas, whilst leaving a flat level patch of filler that would come closer to conforming to the straight edge needed. This technique was done a few more times and is quite effective at leveling up an undulating curve.




That's enough for now. Any comments and advice would be appreciated..


David H

[JHapprich]

The prop looks great, David! Did you produce a special profile for the blades? They look very thin

[HardRock]

Outstanding work Dave.

[Davidh]

Hello, busy week.

Finally the hot weather has arrived just in time for Christmas. Too much ham, turkey and Pavlova. Kids in the pool and food coma's.

Anyway back to the build.

As mentioned i spent a bit of time working on the back end with getting it smooth and making sure that the profile was right as it gently tapered towards the rear end. The 10mm profile lines helped make sure that the taper was just right. After this was done I couldn't resist giving it a coating of resin. The challenge of course from here would be getting the sides to remain at a constant taper whilst cutting the top off in a gradual section that slices more aggressively towards the stern, and making sure that the cuts both top and bottom line up neat with the Jarrah strip,glued horizontally along the end. I then had to plot the lines over the top of the stern. Two lines starting at either side of the end and running up the length of the back culminating in an ellipse that from side on would simply look like and tapering cut that would run down to the very stern and Jarrah strip. This was tricky to plot and get right. It would also not be easy to cut as I was trying to hold level a block of wood that was not level but has a distinctive taper along the edge that would be running along the bandsaw.



I cut out and made a block that I nailed onto the side of the piece. Located just forward of the Jarrah strip it was the difference in height between the end with the taper and the full diameter at the front end. This acted as a cradle to support and keep the piece straight and level while I was conducting the curved cut with the bandsaw. Once these cuts were done I could then go to the disc sander and give an overall sanding to the end section, using the Jarrah strip as a means of checking for level and consistency between the top and bottom cuts. This is where having the sections of timber is useful because I could see the section lines giving a consistently even profile looking back along the length of the stern section looking forward. There are a couple of profile lines that are showing undulations and areas that needed sanding down. The far pic shows this. From now its just lots of sanding and eyeballing.....






I have been spending a bit of time developing the appendage parts that would be needed for such a kit. These once again would be developed using my favourite 3D program "Blender". This fantastic dutch program is one that I use heavily for teaching my year 9's and 10's. Some of my students have now developed skills in this program that leave mine for dead. However for basic modelling and detail it is great.
It is amazing what you can build with just three hotkeys for Scale, Extrude and Rotate... Blender models lend themselves to 3D printing superbly. You just need to export them to STL files.




As can be seen here I have worked on the development of the 667's screws. These have taken a fair amount of time. I looked at heaps of photos of propellers of both the Oscar (Project 949) and the Delta fours to get the nuance right of the subtle shapes of the blades. The curves of these blades being diabolical to get right. I made several attempts at getting the curves correct, finally creating one blade from the ground up (vertice by vertice for those who know Blender). Once one blade was just right, create a central hub, (easy) then duplicate and rotate and repeat six times. Needless to say the upper rudder sections were easier to work with and took a lot less time to produce.

Suggestions or comments please...

David H

[Davidh]

Hello all,

Thanks Jorg, Not quite that quick..

As can be seen the bow section is reasonably straightforward. It turned up quite well. After the resin coat had been applied and sanded back there would be little to do until it was time to start marking out the main details then dremelling them out, filling it sanding and scribing the details into the substrate. The back would be more challenging..

As with the front, the back would start off with a series of blocks glued together overnight, about twice the number than the front, I wanted to make sure that the "sleeve' that fits into the rear of the PVC tube was quite size able and good snug fit. As with the front, mark out the center in order to drill holes for the face plate to be bolted to. Then attached to the lathe and slide the tail stock up to meet the other end. Once this was done the slow initial start to turning could commence. Scraping tool and taking out chucks, thump, thump, thump...low speed.





As this big collection of timber bits started conforming to round, you could see the overall shape emerge. I really like using sections of timber because as mentioned it gives good sectional lines that you can use later on when marking out and aligning. It does mean that when you are turning you have to be careful about the face that you come across different densities of material and this can thrown a consist line of cut that you are aiming to achieve. You just have to go steady. Unlike using Renshape you have grain to deal with and it tendencies to pull you this way or that and as mentioned fluctuating densities don't help either.

With the pieces that I am using I realized that as soon as uniform round profile was reached I would need to go slow as the diameter needed would come up pretty soon. The PVC pipe is 90mm so as it was approaching 94-92mm, I had to be careful and make sure that the density difference would not spell disaster as one section may drop below 90mm. Not good.The outside calipers are awesome.



As soon as I got the head stock end close to the required 90mm I them marked out the line where I would cut a reduced section to make the 'sleeve' that would fit in and under the PVC pipe. This would be 20mm long and would be a reduced diameter of 86mm. I cut out a section of PVC pipe that I would slide over the head stock and push onto the end sleeve as it slowly came down to the right diameter. I made up a template based on the stern drawings of the 667 that I have been working off. This profile would help me determine the overall curve of the stern section. The stern section of the 667 has a very straight taper. There is very little gradual curve in it.. I would refer to the drawing in which I created a series of perpendicular lines every 10mm along them stern section where to the taper occurs and taking the outside calipers to make sure that the radius was what it should be at any given point. This has turned out to be a quite good way of ensuring that the overall profile is as accurate as I can get it.






Once i was happy with the overall taper and the diameter was reducing where and when it was needed I could them smooth it down. I have also glued a piece of Jarrah (Australian native hardwood) along the center line caused by the tail stock. This would be useful for alignment and also it would be the surface that I would cut down to to create the sloping top and bottom flat sections that would slope upwards to the stern before the transition to the twin booms. For my birthday in November I was given a laser leveler. These things are awesome. Get it all Zero Bubble and straight and it will give a dead straight line. Nice. This will feature often in this build and really handy device to have.

[JHapprich]

So you are taking your time on it... i then expect the stern being done by early next week ;-)
Regards

[Davidh]

Hello all,

Thanks Gantu for the pics, some gems in there....

So I had spend a couple of months doing some research and collecting photo's of the Delta 4. As mentioned I also looked over the web for good three view drawings of this boat. Some are better then others and the best ones I have found on some Russian forums. I don't understand a word of Russian so i just type in 'Npoekt 667' that seems to get me in the right sites. After getting a good three view drawing I scaled it up and printed it out to the right size to make 1/140. Marking out the centre axis lines on both the top and side views I then ruled a series of lines 10 mm apart perpendicular to the axis lines that I would use a diameter checks along the hull specifically at bow and stern as the hull curved in. This would help me work out what the diameter should be at any given point.

I would be turning up a rear and front section with the middle being a PVC pipe of 90mm dia. So one afternoon after school, I went into the workshop and looked around for scrap blocks of 120 x 120 x 40mm thick
pine blocks to glue together. I would need quite a few for the front and even more for the back. Cut them roughly square and glue them together with PVA glue. Came back the next day to find two stacks of glued blocks. Taking pencil and try square I ruled where the approximate center should be and found four screws to drill through for the face plate mounting for the lathe. Once positioned I drilled four holes through the holes in the face plate and screwed in the self tappers to hold the face plate in approximate center. I could now mount it to the lathe. This would be the bow section. The easy bit.



Starting off on the lathe with such an ungainly piece of timber is always a really messy, dusty way to start things. You a chipping and scraping away with a big cutting tool with no finesse. You are just working hard to get it nice and round. The dead center on the tail stock is pushed up hard against the other end to provide some more support. The chisel bucks out as you hit a bump and you have to be careful not to blow and chunks where you have hit a weak point or the grain at just the wrong angle. Soon enough the shape becomes round and you need to care fully make sure that the diameter does not dip below that of the intended PVC pipe you are going to use. A small section of it will, that is the section of turned end that will slide in under the pipe and allow you to secure them together. I took my calipers and every minute or so would check the diameter as I inched closer to the required 90mm. I have a small section of PVC pipe that I have cut to go over the face plate of the lathe. This is a quick way of making sure that the reduced diameter section will slide over tightly. It rattles around a bit when not on the wood part. However once I get the smaller section just snug I fit it over and make sure that the rest of the turned section will have a diameter that just brings it up to flush with the PVC pipe.





As mentioned before, there are some really good pics of 667 BDRM. These dry dock photo's are fantastic. They give a huge amount of information has been really beneficial. Once the front section has been turned to the appropriate diameter I could then look at the profile of the bow section. The Bow on 667 is pretty symmetrical the top and bottom curved don't really deviate. So turning them is reasonably easy. I will later on be giving a slightly smoother and lower gradient to the top part of the bow as it sloped down. Disengage the tail stock and once happy with the overall shape of the bow I then took to it with some smooth paper. Starting off with 180 and moving up to about 400 grade. Quite smooth after a while. Unscrewing the piece from the lathe I took it home and gave it a coat of resin. This shows up the grain really nicely. Almost a pity to cover it. Then the next morning back to school, mount it on the lathe and go at it with the sandpaper once more.



I started off by sanding with 120 very briefly them moved on to 180 then soon enough was down to 400. Once then was done you could really see a smooth consistent profile that would be the front bow.
It would be time to work on the stern soon and this would be a lot more involved. I took the bow section off and took it home. I then press fitted it to the section of PVC pipe what will make up the amidships section. A nice snug fit with no slop. This will be help on with countersunk self tappers.



As with all the wood sections that I am doing, when detail is involved I will be using a Dremel to grind out paths along the surface.
then filling them with filler, sanding back and then scribing the detail. As mentioned i simply don't have enough Renshape to do entire bow and stern sections in the stuff, as much as I may like to. I have decided unlike past projects that the bow section, the PVC amidships and then stern will be separate as much as possible during build so that I don't have to wield an ungainly large model around. I will only permanently connect them when i need to start working on the transition details around where they all join. This will make each section easier to work around. I will probably need to bring them together now and then for alignment and registration of details needed by all, a good example being axis lines and symmetry issues.

Anyway enough for now.


David H

[Slats]

Hello Peter W, John and Gantu,

Thanks for the comments. John I will be keeping it at 1/140. This will be in keeping with the Borei. I understand that 1/144 is a more practical close scale to gravitate towards, however it is a major hassle
with PVC pipe diameters and you know me, I tend to just build the boat and think about scale later. Building to a particular scale has never really been on my radar. I know it makes sense to, but that's just the way I roll. It's going to be slightly shorter than the Borei and will be a really good size for any one who wants one. Did you get the radio issue fixed? Also are you back on the forums for good? Taken a break from all the study. It would be good to catch up with you again, its been a while.

Peter W. I'm looking forward to the build. Gantu I'm sure you have some gems. Do you have any inlet scoop pics?

David H

You and scales ....SHEZZZ!

Nope on Radio - it's my son's boat and he can live with 5 channels.

Yes hopefully going to get back into it. Handing in big draft of the Doctorate this week to my supervisors. 104,000 words - 602 references - some of it legible - the light at the tunnel is getting bigger and wider and doesn't look a train coming the other way. 3 subs on the slipway - all 1/72.

[gantu]

On the way david

[Davidh]

Hello Peter W, John and Gantu,

Thanks for the comments. John I will be keeping it at 1/140. This will be in keeping with the Borei. I understand that 1/144 is a more practical close scale to gravitate towards, however it is a major hassle
with PVC pipe diameters and you know me, I tend to just build the boat and think about scale later. Building to a particular scale has never really been on my radar. I know it makes sense to, but that's just the way I roll. It's going to be slightly shorter than the Borei and will be a really good size for any one who wants one. Did you get the radio issue fixed? Also are you back on the forums for good? Taken a break from all the study. It would be good to catch up with you again, its been a while.

Peter W. I'm looking forward to the build. Gantu I'm sure you have some gems. Do you have any inlet scoop pics?

David H

[gantu]

David i do need your emailadress. Files ready to go
Gantu

[Peter W]

Subscribed ! ....going to enjoy this one David !

Peter

[gantu]

Soon on the way............................