USS Greenling (SSN-614) Scratchbuild

[rdutnell]

Re: USS Greenling (SSN-614) Scratchbuild

UPDATE 15
While doing the Anti-skid coating outline I discovered a couple of things. First, the best way to do it is to retrace the entire projected line with a 3D polyline. The second is that circles are better than squares for cutting the groove, because if you put the center of the circle on the polyline half of it is “submerged” and half of it is in the open. No matter what angle the surface is, the same cross section is being cut. After doing the Anti-skid coating outline, I thought it looked so much I decided to redo the water line too. The trouble is that I don’t know how to undo major changes like that, so I had to go back a ways and redo both the waterline and the Anti—skid coating outline. That’s one of the problems with working with AutoCad. You really save the file with a new name after each major change, so that you can go back without having to go too far back. Oh well, redoing stuff over and over just provides more practice. Anyway, I think the lines look pretty good, at least on the AutoCad model.


After doing that I was thinking about mounting it so I “drilled” ¼” diameter holes through the bottom of the hull in the center of the two center pieces. I then provided a ½” platform on the inside so the hardware would sit flush rather than against the curved hull. Upon further thought I decided to build a recess for a 1/2” nut to fit snuggly into. A nut can then be glued in place prior to assembly. This will make life easier when it comes time to mount it. To provide extra support I added small wing walls to the recess.




CHEERS!!!

[rdutnell]

Re: USS Greenling (SSN-614) Scratchbuild

UPDATE 16

I was looking at pictures and it suddenly dawned on me that although my design has a moveable rudder and diving planes, the sail plane is stationary. I should say was stationary, as I redesigned it.



The holes are 1/16” diameter. They are drilled 0.35” into the planes and all the way through the sail.

With this addition and the fact that since I am putting detail on the hull before it is made, the two mid-sections are different, I developed a more recent part diagram.

CHEERS!!!

[scott t]

Re: USS Greenling (SSN-614) Scratchbuild

This is looking great! How about adding raised draft numbers on the hull?


Scott T

[tom dougherty]

Re: USS Greenling (SSN-614) Scratchbuild

How about adding raised draft numbers on the hull?

Raised draft numbers?? What do you think this is, Lindberg Models in 1958?

[rdutnell]

Re: USS Greenling (SSN-614) Scratchbuild

Sorry Tom, I don't get the Lindberg Model reference. I was born in 1958.

As far as raising the numbers Scott, were they actually raised or just painted? Everything I know about submarines I've learned in the last couple of months when I started this adventure, but it seems that adding raised surfaces on the hull would be contrary to trying to keep it sleek for noise reduction.

If they were in fact raised, this would be quite possible. Text can in fact be placed on a surface and either raised or engraved. Here are a couple of pictures of a test piece I made to see the effects of different surface detailing methods.



I made the piece mainly to see what width and shape made the right size groove in the surface. I was curious to see if text could be extruded and manipulated like any other object and indeed it can. To see what it would look like I used one side to test various text treatments, depressed 0.005", raised 0.005" and raised 0.01". It is likely that it will be made this week and I will have it in my hot little hands by the New Year. The test piece by the way is a 1" mostly hollow cube. You may have noticed that there is something inside of it.

I am also doing a test to see if the process can make 1/350 scale RAM launchers, so there are 2 rows of 4 launchers inside that I atached to the inner wall with thin "sprue". I made the RAMs in AutoCad too using pictures and 3 dimensions, the height and the length and width of the launcher, provided me as measured from a 1/350 part, so I don't know how accurate it is, but I think it will be good enough for the scale it is, if the process can even make it. A lot of the detail is less than the 0.005" resolution of the process.


But I digress,
Considering scale... At 1/144 scale 0.005" = 0.06', which is about 3/4", so if the test was indeed raised on the surface, it would indeed be practical to do as Scott says and add the numbers to the surface.

So were they raised?

[rdutnell]

Re: USS Greenling (SSN-614) Scratchbuild

UPDATE 17
I decided to have a go at the hinged cleats. I didn’t have much to go from, just a couple of pictures, with this being the best one][/url]
Here are some different views of it.


It’s not bad, but it’s not quite right. I think it needs to slope up a little more and perhaps be a little fatter. If anybody has any good pix or plans of one of these cleats, they would be much appreciated.

CHEERS!!!

[tom dougherty]

Re: USS Greenling (SSN-614) Scratchbuild

Sorry Tom, I don't get the Lindberg Model reference. I was born in 1958.
As far as raising the numbers Scott, were they actually raised or just painted?

The draft numbers are painted on. The 1958 reference was to older styrene kits, such as Lindberg & Revell, which had slightly raised areas on the model in the shape of decals to indicate the placement of decals. You can see an example here]http://www.oldmodelkits.com/blog/wordpress/wp-content/uploads/2011/01/bruget-4.jpg[/url]

[rdutnell]

Re: USS Greenling (SSN-614) Scratchbuild

UPDATE 18A
Thanks Tom! I thought I sensed some leg pulling going on there. What classics those old models are!

The Details of Detailing – Part 1

In my next two posts, I thought I would show the steps I am going through in the etching process. Below you see the underside of the ship in the area of interest. Forward is to the right. You can see one of the mounting holes I drilled on the right, and some of the detailing I have already done on the left. The first image is in “Realistic Visual Style” but you can see the plans around the perimeter of the model. The second image is in “3-D Wireframe Visual Style” and you can clearly see the plans, with the wireframe of the model superimposed over it. Note the coordinate system in the lower left hand corner and the “View Cube” in the upper right hand corner. These will be on all images showing the orientation. For this example I will be detailing a small undefined circle identified by the red circle.

I don’t have any idea what all of these little unidentified circles that are numerous throughout the ship are, but whatever they are, I’m giving them all the same treatment. They are circles with 0.025” radius and I am etching them on the ship using a revolved circle of 0.005” radius.
The first step is to locate the center of the circle relative to the plans. Since I want the circle to be below the model, I use a polyline to connect a low point on the hull (i.e., the outside of the hull at the center line) to what looks like the center of the circle on the plans. I use polylines because they are at a constant elevation (or height) based on the elevation of the starting point. Lines (can) have different elevations on the end points. So if I used a line and clicked on the center of the circle that end of the line would go to 0 and screw things up. Not so with a polyline.

Now I draw a circle with radius 0.025” at the end of the polyline I just drew.

The plan isn’t needed anymore for this process, so I turn off the layer it is on. When I do this items on the top of the ship are visible, and can be distracting but through experience I have found it is better than leaving the plan layer on.

Now I reference the location of the circle to the center line of the ship by drawing a line from the center of the circle (the end point of the polyline I just drew) perpendicular to the center line.

I then rotate the image to get a better perspective to make sure that everything is where it is supposed to be. It looks good so far.

So, now I go back to plan view and go back to 3-D.

Good, the circle is below the model. I now rotate the model again and zoom in to get a better view for the next steps.

In this case the circle is really close to the surface, but I still need to execute the PROJECTGEOMETRY command to project the circle onto the surface of the hull. The projection has to go perpendicular to the centerline.

Now that I have the feature I want, I delete the lines I don’t need. This includes extra projections because the projection goes on every surface it sees. I keep the line that goes to the center line because I need it for orientation on the next steps. So the next step is reorienting the coordinate system with the z-axis along the radial line and drawing a 0.005” radius circle with the center of the circle on the projected spline. I typically change my drawing color at this time to yellow.

More to follow...

[rdutnell]

Re: USS Greenling (SSN-614) Scratchbuild

UPDATE 18B
Detailing Details Part 2

Here’s the rest of the procedure I'm using for the detailing…

I now have to rotate the circle I just created, and I do this using the 3DROTATE command.


Now I use the EXTRUDE command using the spline as the path. But first, sometimes when I extrude on a spline it moves, so I have to provide a reference point to get it back to the right place, so I draw a line through the center of the spline.

This was one of those times, so I draw a line through the center of the new “donut” and move it from center point to center point. (Note that I changed my view orientation too).

Now I delete all excess lines and turn on 3-D. If I did it right, only half of the donut should be protruding from the surface.

EXCELLENT!!! Now I go to the original plan view, turn on the plan layer and go to Wire Frame to check aligment one last time (hopefully).

Gotta love it! Now for the cool part. But first I should point out that if I am doing a feature on the sides I use the MIRROR command to create a mirror image of the donut on the other side of the hull, but since this is on the bottom I don’t have to do that step. Now I pick a good oblique angle to look at it, turn on 3-D and use the SUBTRACT command.

The donut is now a recessed groove in the part. The last step is changing the color to the color I’m using for the hull.

And a final oblique shot to look at the fruits of my labor.

Note that there are a couple of “saucer” looking objects. These are 0.01” depressions for the MSW Sea Chests that I plan on using metal, either brass or stainless to make and these are depressions to take the metal.

So, that’s all there is to it and just like working on a jet engine or car, describing it makes it more complicated than it is. Of course this was a small easy piece, but the more intricate ones aren’t that much different to do.
I hope you enjoyed this, now back at it.

CHEERS!!!

[rdutnell]

Re: USS Greenling (SSN-614) Scratchbuild

UPDATE 19

Good Morning Guys, Here are some images of the detailing I have completed thus far.

In the first image you can see (looking left to right) the anchor light on the rudder, the cut out area for MBT Valve No. 7, the etching for an unidentified circle, the etched anti-skid coating outline, and a padeye.

Obviously, the light isn’t real. I was considering putting real lights in it, but I’ve all but abandoned the idea though, because I would have to abandon the moveable rudders, because there simply isn’t enough room to do both. On the other hand, lights would probably be cooler and add more to the model than a moveable rudder.

A few posts back wlambing questioned the location of the MBT Valve No. 7, but every plan or pic I have seen has a valve there, so I included it. I think that the unidentified circle is a salvage air port, whatever that is. Anyway, I gave it the treatment I described in the last couple of posts.

I put a sonar fearing on at one point based on a rough set of plans for the “Modified Permit Class SSN (Circa 1985) – 614, 615, or 621 Version” and a photo of Greenling in dry dock that show that she had a fearing. The fearing came on after my buddy was on the ship, so as cool as it was, I took it off.

The padeye is a WAG because I have no idea what this particular padeye looks like. I just put a basic handle looking thing on it. This could easily be replaced if I discover what it really looks like.

In this view of the underbelly, you can see (again from left to right) the mounting hole I “drilled” and engravings for the No.5 flood hole baffles, the secondary propulsion unit, the No. 6 flood hole baffles, and a couple of miscellaneous little circles, as well as cut out spots for the MSW Sea Chests and ASW Suction.

I’m giving some thought to maybe having the secondary propulsion system on the outside, but for right now I just have the location etched. The MSW Sea Chests and ASW Suction are going to be made out of either brass or stainless steel, so they are cutout to accommodate this.

Returning to the top side the photo below shows (from aft (left) forward) an unidentified circle (again probably a salvage air port), a hinged chock, an access hatch, the aft escape trunk, another unidentified circle, an escape hatch, an unidentified feature and two hinged cleats.

The access hatch is to be made out of metal so it is a recess. I was going to do the escape trunks out of metal too, but when I saw a picture of them I thought that I could create a more realistic effect if I included it on the plastic part as it is made. I’m really happy with the way it turned out on the AutoCad part. We’ll see how it looks on the real part.
The hinged cleats were replicated from essentially one photo, the ever famous and popular “manwatch8” that the escape trunks were also based on. They are essentially two different sized ellipses lofted along an elliptical arc. The ones you see aren’t yet wed to the hull, but the groom is about to kiss the bride, so if you have any comments on them, speak now or forever hold your peace.

CHEERS!!!

[tom dougherty]

Re: USS Greenling (SSN-614) Scratchbuild

This is great fun watching you work through this project!

[rdutnell]

Re: USS Greenling (SSN-614) Scratchbuild

UPDATE 20

Hi All!

Tom, I am so glad that you are having fun watching my journey through this adventure, I certainly am enjoying it. It’s bringing together so many of the things I enjoy doing, playing with AutoCad, modeling, learning, and since I am posting my progress, writing. And when I got to hold the parts that I had designed, it was awesome, and that was before I did any detailing. I had no idea when I started this project that it was going to be this enjoyable, and like I’ve said before, then I still get to build the model itself. LIFE IS GOOD!!!

This morning’s update deals with the metal parts, but first, here is an image of the area around the aft escape hatch, where I am currently playing.


As you can see, I decided to display the retractable capstans in the deployed position. The only thing I had to go on for the design was a small sketch of the part on the plans that I have. If it is drastically wrong, it could be changed, but I think it looks pretty good (especially since it is only 0.11” tall). The cleats and hull are now happily married and soul mates for life, though under dire circumstances, they could always be parted.

I have mentioned a few times that I plan on making some of the parts out of metal, but I haven’t really provided any details. Well, the deal is that my buddy that’s making the parts for me says that they have a laser cutter that he could use to cut out parts for me. It isn’t photo etch. As I understand it, it’s just a laser cutter, but my friend isn’t really clear about this because I don’t think he really understands the laser’s capabilities. My experience with using a laser cutter for wood, and I imagine the principal is the same, is that you can adjust the beam strength to either cut or etch. That is how I did the inlays for a gate I built a few years ago. The recesses were cut using a raster, set at a low setting; the inlays themselves were cut with vectors using a higher intensity. Perhaps etching will be possible, but at the moment I am assuming not.


My buddy says that I can use stainless or brass of any size, and I am currently leaning toward 0-006” - 0.01” stainless, but this isn’t set yet. To design the metal parts, I am using the dimensions from the plans together with “Oliver’s PE” so graciously provided to me by Joel. Thanks again Joel!!!

I am making the pieces I need as I encounter them on the ship and etch the hull. This is what I have so far…

This might change however, because I also stumbled across these files (one that Joel sent me, the other I am not sure of the source).


I have plenty of time for those changes, so back to the “scribing”.

I want to reiterate that if you see something that is just flat out wrong let me know so I can change it. Remember, I don't really know what the heck I'm doing. I'm just winging it.

CHEERS!!!

[rdutnell]

Re: USS Greenling (SSN-614) Scratchbuild

WOW!!
I've been using PostImage. Switched to PhotoBucket because PostImage wouldn't open. A little harder to upload, but way better appearance!

[rdutnell]

Re: USS Greenling (SSN-614) Scratchbuild

UPDATE 21

Good Morning All!

I spent pretty much all of Saturday and Saturday night playing on AutoCad and made really good progress on the model. One of the things I did was have a crack at making the Secondary Propulsion Unit, which is the topic of this update.
I started by tracing half of the outline of the SPM (Secondary Propulsion Motor) using part of a circle, a line and an arc. I then mirrored it, joined the two and revolved it around the central axis to get the solid body. The propellers were just made from a single ellipse, which I extruded 0.005”. (The images were uploaded with PostImage because you can upload files all at once instead of one at a time.)

After extruding the ellipse, I switched to the top view, centered the extruded ellipse and rotated it.

I then switched to the rear view, assumed there were 5 blades and rotate/copied the one blade four times, with an offset of 72 degrees each time. After that I started the propeller shroud by again tracing half of the foil, mirroring it, joining the two pieces and revolving the whole thing around the central axis.


Supports for the shroud were next. These again started with just a single foil in the same manner as described before. I then extruded it from one side of the shroud, through the hull, and into the other side of the shroud. When I was happy with it, I rotate/copied it 90 degrees and used the UNION command to join the whole mess together.

The base was next, and for that I went to the main drawing to clip and paste the outline of the cutout as shown on the plans, and etched into the hull. (Note, the red part isn’t in the wrong place, it is straight down from the actual location)

I took the copied shape, positioned it where it needed to be and extruded it 0.02”. The supports are once again foils. In fact, I copied one I had already done and scaled it match the drawing posts.

The one support at the back seemed pretty flimsy to me, so I figured that they had to have had supports on the sides too, so, I added some, and once again they are foil shaped. After that it was just the shaft and collar, Unionization and TADA! It was done and looking pretty good I think.

I just had to put it on the ship, which turned out to be more of an ordeal than I thought, mostly because AutCad was glitching and wasn’t doing what it is supposed to do. I was proving Einstein’s definition of insanity in that I kept trying the same thing over and over expecting different results. Finally, I just turned the &^%%^^ thing off and restated it and it started working again. Oh, computers! The love-hate relationship.

Even without the computer glitch, this was a somewhat tricky proposition. First I made 2 copies of the hull part, SPM, and outline shape off to the side. I extruded the shape through the hull of one of them in the proper location and did an “INTERSECT” command which gave me a chunk of the hull the shape of the outline. I did a couple of things with this. I started by making a copy of it and slicing off a thin section of the outer hull, which I attached to the bottom of the SPM base, so that its outer surface would match the shape of the hull. Using the second piece I copied, so as not to mess with the original, I used one of the chunks and subtracted it from the hull to remove the lower section of the outline. I used another one to remove the upper section. I had to do this because, since the one was such a close fit, AutoCad was leaving one end or the other closed. I kept going back and forth with material on one side, then the other, until it finally dawned on me that I could just subtract it twice in different locations.

I now had a cut out going through the ship, and an SPM with no visible means of support. So, I made a block by extruding a rectangle from one side of the inside of the hull to the other one. The problem is that I want to have the option on whether to display it or not, and if I can figure out a way, make it “adjustable” between deployed and not, so this complicated matters, in that I had to build a little canopy over the SPM and subtract the canopy from the model. I tried to show it in one of the images, but it is difficult to get a good angle at it.



As you can see, the way I designed it, the outer shell of the SPM seats up flush with the hull when in the stowed position. I would really like to make it so you could do either, but the only way I can think of is to put a couple of rods with catches on one side of them, but not on the other. The problem with this is that there would be little plastic screw heads on the hull surface. We’re talking eye glass sized or slightly larger though, so maybe they wouldn’t be too conspicuous.

I hope you enjoyed the update.

CHEERS!!!

[rdutnell]

Re: USS Greenling (SSN-614) Scratchbuild

UPDATE 22
Oh boy are you going to like this. I figured out a way to make the SPM deployable/retractable. Here’s the scoop.
It’s fairly simple really. It’s just four pieces, the SPM (Blue), a load bearing (Magenta), a “ key” (Green), and an end piece/washer (Yellow), and of course there is the hull. For scale, the yellow line is 1”.



In addition to making the three new parts, both the SPM and the hull were modified. A 0.1” hole was drilled in the base plate of the SPM base plate. A recess was created on the outside face to accommodate the end piece/washer, which has a 0.1” ID, a 0.12” OD and a thickness of 0.006”. A recess was created on the inside face to accommodate the key, which has a diameter of 0.3” and is 0.013” thick.

The hull was modified by cutting circular slots (Green) with a thickness of 0.013” and a diameter of 0.3” on the inside to accept the key.

The first step in the assembly is to slide the end of the key into the hole. It should sit flush with the surface.

It should sit flush with the surface of the SPM base. The key is then slid over the end and glued carefully on the end so that it and the key can rotate as one piece. There won’t be any force here so that is not a concern.

Note that the shape of the key is, well, the key to the design’s function. When the screw head (0.3mm) is aligned with the ship the surface is flat for when the SPM is in the deployed position.

When the screw head is turned 90 degrees, the circular disks protrude and nestle into the slots, which supports the SPM in the unused position. In the deployed position the weight is born by the load bearing (hence the name).


So that’s that, and now we just have to wait for the parts to be made to see if it works. The good thing is that with this completed, Part 6, the mid-hull section 2 is ready for manufacture, as are all of the new parts.

CHEERS!!!