SaparotRob
Unter Gemeine Geschwader Murmeltier XIII
Most impressive.
1:48 Engine Room #3 Battleship USS New Jersey for Permanent Display on Board. (1 Viewer)
- Thread starter Builder 2010
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Looks great so far!
- Thread starter
- #83
Builder 2010
Staff Sergeant
After returning from a New Years Eve wedding in Miami, I got a gift from Southwest Airlines; a nice, annoying head cold. This kept me out of the shop, but not off the laptop and a lot of design work contrinued. The HP turbine is done and with accurate drawings of its foundation, I was able to draw that too. I stopped work on that because it was now esssential to finalize the main reduction gear since the MRG's fore foundation also supports the aft end of the HP turbine foundation. I continued designing the steam piping, but see a decision lurking. Too much piping will obscure the wonderful machinery that lies below. I'm also thinking that the undersides of the main piping will serve as convenient locations for LED lighting.
I was able to estimate the actual MRG gear diameters using the overall ratios, the output speed, and the relative space within the housing. I produced a spreadsheet to do the calculation. There is a slight difference in diameters between the first pinion on the HP and LP sides. The HP input rpm is 4,905 and the LP is 3,913, but the second pinions on the bull gear have to be spinning at the same speed to create the 202 rpm at the properller shaft. After doing all this, I realized that viewer will not discern any difference so I made both sides the same. I'm cutting away the gear covers on both sides so the innerds can be viewed from either direction. i did a test setup in the print slicer to print the gear set (sans bull gear) as a single part facing vertically so no supports will go on ANY gear teeth. It will work.
This was a very challenging piece to draw. I was fighting all the usual SketchUp challenges coupled with the mechanics of creating parts that will assemble correctly.
The frames were equal on both sides. I drew the overall shape and then slice in half using a big rectangular brick as the cutter and insecting the faces and removing the half I didn't want. You group the good half, MOVE-COPY it directly next to it, and mirror is using the MIRROR tool. Match them up a mating corner, explode both parts and then remove the center line making them a single part with perfectly symetrical features on both sides.
Another annoying, but necessary detail with making a SU drawing 3D printable is all the faces being "normal" not reversed. I set my default colors so reveresd faces are quite obvious. When reboring some of the bearings, the inside faces come out reversed. If this was just for an illustration, it wouldn't matter a whit, but to print they must be all forward faceing. I had to go back and reverse then on facet at a time. It's very finicky, time-consuming work that must be done. Reveresed faces are seen as missing in the slicer and missing faces don't print. This screen shot was taken in the middle of the face reversing task.
I "line bored" the bearing mounts by creating a set of shafts that were used to "cut" their channels in all the support struture. Even with this cleverness, I still created problems for myself when I didn't have the frames properly aligned when I did the cutting. I have to close up all the bearing holes and redo the whole operation. I used the same setup to cut corresponding bearing in the gear covers.
Speaking of gear covers. While seemingly uncomplicated, they took a lot of hours to get resonsable. I was shaping them without paying enough attention to my pictures. Like the gears, I don't have technical drawings of these highly-visible parts. When you come down the ladder into the engine room, the first thing you see is the top of the MRG. I tried to fix my errors, but gave up and redrew the part from scratch. Since the same on both sides—although one side has the electrical turning gear attached—Made one, copied it and then mirrored it using a -1.00 scale factor.
When I first drew the gear covers I had the lid face curved on all sides. After closer look at the pictures, it was only curved on the front and back edges, not the sides. Making the curved edges is EASY. I have an SU Plugin, Fredo6Corner, where you dial in the amount of edge to be curved, select the edges and click. Voila! Curved edges. But… to fix curved edges, or in this case, remove some of them and re-square the edges, it's a complete pain-in-the-derriere. It's not hard to erase the curve, but it's very finicky, re-laying the lines to create the square edge. You make heavy using of SU's "inference" facility that highlights the line end that corresponds to an adjacent/nearby edge. You draw out one segment at a time to the inference point of the bottom line, and then connect these lines to make faces, and finally close the long wall. It's complicated to write about it and complicated to pull it off. This shows the lines pulled out to the correct distances waiting to be connected to the same form on the other end of the part.
Today I spent time building the output end of the MRG. I didn't have a drawing of this, but a good photo I took. So the upper works are complete. I still have work to do on the MRG lower foundation and lubeoil tank upon which it all sits. The cutaway area is what's going to be printed.
The X-ray view shows the bull gear and why the housing so darn big. The bull gear is about 13' in diameter. The real one could be bigger or smaller. I don't have any information about it, but this size fits the housing appropriately, and I do have housing drawings.
So here's some eye candy to brighten up a cold winter day (for us Northern Hemisphere folks). It's definitely starting to shape up. Notice that there's now machinery on the top of the main condensate pump. The big four (HP/LP turbines, MRG and Condenser) are now almost finished. I don't expect that any of the auxiliary equipment should be more difficult.
This is the high pressure side:
And the low pressure side:
I was able to estimate the actual MRG gear diameters using the overall ratios, the output speed, and the relative space within the housing. I produced a spreadsheet to do the calculation. There is a slight difference in diameters between the first pinion on the HP and LP sides. The HP input rpm is 4,905 and the LP is 3,913, but the second pinions on the bull gear have to be spinning at the same speed to create the 202 rpm at the properller shaft. After doing all this, I realized that viewer will not discern any difference so I made both sides the same. I'm cutting away the gear covers on both sides so the innerds can be viewed from either direction. i did a test setup in the print slicer to print the gear set (sans bull gear) as a single part facing vertically so no supports will go on ANY gear teeth. It will work.
This was a very challenging piece to draw. I was fighting all the usual SketchUp challenges coupled with the mechanics of creating parts that will assemble correctly.
The frames were equal on both sides. I drew the overall shape and then slice in half using a big rectangular brick as the cutter and insecting the faces and removing the half I didn't want. You group the good half, MOVE-COPY it directly next to it, and mirror is using the MIRROR tool. Match them up a mating corner, explode both parts and then remove the center line making them a single part with perfectly symetrical features on both sides.
Another annoying, but necessary detail with making a SU drawing 3D printable is all the faces being "normal" not reversed. I set my default colors so reveresd faces are quite obvious. When reboring some of the bearings, the inside faces come out reversed. If this was just for an illustration, it wouldn't matter a whit, but to print they must be all forward faceing. I had to go back and reverse then on facet at a time. It's very finicky, time-consuming work that must be done. Reveresed faces are seen as missing in the slicer and missing faces don't print. This screen shot was taken in the middle of the face reversing task.
I "line bored" the bearing mounts by creating a set of shafts that were used to "cut" their channels in all the support struture. Even with this cleverness, I still created problems for myself when I didn't have the frames properly aligned when I did the cutting. I have to close up all the bearing holes and redo the whole operation. I used the same setup to cut corresponding bearing in the gear covers.
Speaking of gear covers. While seemingly uncomplicated, they took a lot of hours to get resonsable. I was shaping them without paying enough attention to my pictures. Like the gears, I don't have technical drawings of these highly-visible parts. When you come down the ladder into the engine room, the first thing you see is the top of the MRG. I tried to fix my errors, but gave up and redrew the part from scratch. Since the same on both sides—although one side has the electrical turning gear attached—Made one, copied it and then mirrored it using a -1.00 scale factor.
When I first drew the gear covers I had the lid face curved on all sides. After closer look at the pictures, it was only curved on the front and back edges, not the sides. Making the curved edges is EASY. I have an SU Plugin, Fredo6Corner, where you dial in the amount of edge to be curved, select the edges and click. Voila! Curved edges. But… to fix curved edges, or in this case, remove some of them and re-square the edges, it's a complete pain-in-the-derriere. It's not hard to erase the curve, but it's very finicky, re-laying the lines to create the square edge. You make heavy using of SU's "inference" facility that highlights the line end that corresponds to an adjacent/nearby edge. You draw out one segment at a time to the inference point of the bottom line, and then connect these lines to make faces, and finally close the long wall. It's complicated to write about it and complicated to pull it off. This shows the lines pulled out to the correct distances waiting to be connected to the same form on the other end of the part.
Today I spent time building the output end of the MRG. I didn't have a drawing of this, but a good photo I took. So the upper works are complete. I still have work to do on the MRG lower foundation and lubeoil tank upon which it all sits. The cutaway area is what's going to be printed.
The X-ray view shows the bull gear and why the housing so darn big. The bull gear is about 13' in diameter. The real one could be bigger or smaller. I don't have any information about it, but this size fits the housing appropriately, and I do have housing drawings.
So here's some eye candy to brighten up a cold winter day (for us Northern Hemisphere folks). It's definitely starting to shape up. Notice that there's now machinery on the top of the main condensate pump. The big four (HP/LP turbines, MRG and Condenser) are now almost finished. I don't expect that any of the auxiliary equipment should be more difficult.
This is the high pressure side:
And the low pressure side:
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Vic Balshaw
Major General
I can probably count on two hands the amount of times I have travelled and NOT ended up feeling ill and believe me I've travelled far and wide in my lifetime. On the positive side you have been able to make good progress on the project, I am impressed. 
SaparotRob
Unter Gemeine Geschwader Murmeltier XIII
With above.
Great work so far!
- Thread starter
- #89
Builder 2010
Staff Sergeant
I'm almost finished designing all the parts of the primary propulsion system. In addition to the drawings, these parts have been prepared for printing. I just placed an order for a larger ultrasonic cleaner to replace my smaller (and no longer working) unit. Bigger parts require bigger cleaning systems. I also ordered another UV curing light to double the illumination in my post-cure box. With the larger box, and with the inverse square rule regarding electromagnetic radiation, the curing power was diminished. The second lamp will solve that problem too.
To the best of my ability I created the aft-end main reduction gear foundation that abuts the bulkhead to the #4 fire room. It's a very hard location to photograph and the drawing of this area in cross-section is equally ambiguous. I never let confusion stop me. I just added my own bit of naval architecture and pressed on.
This shows the aft-end of the MRG and the #3 propeller shaft penetrating that bulkhead. You can see the structural steel retaining the unit, but it's a very oblique view so getting good dimensions was dificult. Furthermore, the space is only about 3' wide and hard, if not impossible, for an 80 year old guy to get any closer. You can see piping and valves buried in there. In 1:48 and considering the lack of visibility, I'm not modeling them! You wonder how a human can reach that valve in 1:1 scale. I found a lot of valves in places like that. It has to be reached from the bilge which lies below all this.
And here's the drawing showing that area from the same side. I challenge you to make sense out of it.
That said, I did get something that can be created in 3 dimensions. And it looks like this.
I also finalized the HP turnine foundation. I was wondering why the #3 fireroom bulkhead was on an angle. I then realize that it wasn't! The entire propulsion system is on an angle to correspond to the slight angularity of the how the propeller is attached to the ship. All four props and their shafts are angled outboard by, what seems to be, about 3 degrees for the inboard and more for the outboard shafts. Notice too on this overhead of the bilge level the amount of abaft space is taken up by voids and armor for torpedo protection. The ship has a 108' beam, but usable space inside is only 80' at the widest. It was a warship after all, not a cruise liner.
I had to come up with a better way to attach the HP turbine itself to the its foundation. The plans show the turbine hovering above the frame rails, but I couldn't determine what's actually holding it there. I extended upwards the inner stiffeners and matched their curved surface to the HP's bottom contours. This will facilitate getting all this stuff together and in line.
I'm planning on printing the entire HP foundation as a single part, again to facilitate alignment and assembly. The new printer should have no trouble executing this. This part would be too big for my now-obsolete Mars 3 printer. Elegoo just announced a new iteration of the Saturn 4 Ultra with a 16K LCD screen, and some other refinement such as an integral vat heater to stabilize resin temperature, plus a light to accompany the included camers. I'm happy with the one I have, and will upgrade again in a couple of years, if I still doing this stuff.
The thing done in this session was to refine and design the #1 & 2 prop shaft bearings. I originally faked this, but then found a good image of the same in the Iowa and, once I have a real thing, I'm no longer at ease faking it. There are a lot of these bearing throughout the length of the shafts. The #1 shaft is 340' long!
Just to keep y'all from getting too excited, there's still a massive amount to design, including, but not limited to, 2-1,250 KW auxiliary turbo-generators and their condenser systems, the deaerator, 3-evaporators to generate potable and feedwater from seawater, lots of small pumps and auxiliaries, the main control panel, electrical panels. And then there's the labyrinth of catwalks, gratings and ladders. Of the latter, I'm quickly coming the realization that too much of this these will hide a huge portion of the equipment itsef. The goal is to show the equipment in ways you can't see when visiting in person. I have to include some ladders and platforms for scale, but not all.
To the best of my ability I created the aft-end main reduction gear foundation that abuts the bulkhead to the #4 fire room. It's a very hard location to photograph and the drawing of this area in cross-section is equally ambiguous. I never let confusion stop me. I just added my own bit of naval architecture and pressed on.
This shows the aft-end of the MRG and the #3 propeller shaft penetrating that bulkhead. You can see the structural steel retaining the unit, but it's a very oblique view so getting good dimensions was dificult. Furthermore, the space is only about 3' wide and hard, if not impossible, for an 80 year old guy to get any closer. You can see piping and valves buried in there. In 1:48 and considering the lack of visibility, I'm not modeling them! You wonder how a human can reach that valve in 1:1 scale. I found a lot of valves in places like that. It has to be reached from the bilge which lies below all this.
And here's the drawing showing that area from the same side. I challenge you to make sense out of it.
That said, I did get something that can be created in 3 dimensions. And it looks like this.
I also finalized the HP turnine foundation. I was wondering why the #3 fireroom bulkhead was on an angle. I then realize that it wasn't! The entire propulsion system is on an angle to correspond to the slight angularity of the how the propeller is attached to the ship. All four props and their shafts are angled outboard by, what seems to be, about 3 degrees for the inboard and more for the outboard shafts. Notice too on this overhead of the bilge level the amount of abaft space is taken up by voids and armor for torpedo protection. The ship has a 108' beam, but usable space inside is only 80' at the widest. It was a warship after all, not a cruise liner.
I had to come up with a better way to attach the HP turbine itself to the its foundation. The plans show the turbine hovering above the frame rails, but I couldn't determine what's actually holding it there. I extended upwards the inner stiffeners and matched their curved surface to the HP's bottom contours. This will facilitate getting all this stuff together and in line.
I'm planning on printing the entire HP foundation as a single part, again to facilitate alignment and assembly. The new printer should have no trouble executing this. This part would be too big for my now-obsolete Mars 3 printer. Elegoo just announced a new iteration of the Saturn 4 Ultra with a 16K LCD screen, and some other refinement such as an integral vat heater to stabilize resin temperature, plus a light to accompany the included camers. I'm happy with the one I have, and will upgrade again in a couple of years, if I still doing this stuff.
The thing done in this session was to refine and design the #1 & 2 prop shaft bearings. I originally faked this, but then found a good image of the same in the Iowa and, once I have a real thing, I'm no longer at ease faking it. There are a lot of these bearing throughout the length of the shafts. The #1 shaft is 340' long!
Just to keep y'all from getting too excited, there's still a massive amount to design, including, but not limited to, 2-1,250 KW auxiliary turbo-generators and their condenser systems, the deaerator, 3-evaporators to generate potable and feedwater from seawater, lots of small pumps and auxiliaries, the main control panel, electrical panels. And then there's the labyrinth of catwalks, gratings and ladders. Of the latter, I'm quickly coming the realization that too much of this these will hide a huge portion of the equipment itsef. The goal is to show the equipment in ways you can't see when visiting in person. I have to include some ladders and platforms for scale, but not all.
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Excellent work so far!
SaparotRob
Unter Gemeine Geschwader Murmeltier XIII
- Thread starter
- #93
Builder 2010
Staff Sergeant
One of my blog readers on another forum that I post this story, sent me links to two Ryan Syzmanski videos that addresed the prop shafts. I was very happy with my 24" prop shafts. I thought I read somewhere that this was their diameter. Then I looked at the video and found out that they're 32" in diameter, and solid steel except for the 8" hole down their center. Once I know an "actual" dimension I'm compelled to make the model conform.
That generated about 2 hours of work modifying everything affected by the prop shaft. I also got a good view of the bulkhead Prop Shaft Seals so I changed them also. The 24" shaft scales nicely to a 1/2" in 1:48 so I could use a standard piece of tubing for it. At 32", it scales to something between 5/8" and 11/16". I'm going with 5/8"… 32" is 20% bigger than 24" so I was able to scale up the spring bearings and their supports. I also got a good view of the prop shaft couplings enlarged its thickness and then scaled it up 120%.
I didn't scale up the MRG's output bearing becasue they wouldn't fit in the space. Instead, I intersected the front face with the new diameter shaft and redrew and edited the parts with the new diameter. It also changed the tapered end and that… was a pain in the butt. As I've said many times before (and it's worth repeating), in SketchUp, it's often easier to draw a part from scratch than to modify it.
The new shafts do look much more massive and, frankly, look bettter to me.
I pause videos that have useful imagery and then do a screen print isolating the parts I want. I did the same with the other video and found some good still images that I didn't have in my reference library. Every image, even if it's just a small detail that is exposed, is worth it.
Shame on me for exporting a lot of these affected parts as STLs and then producing sliced print files. I now have to go back and do some of them over again. I was jumping the gun.
Also, my new Ultrasonic Cleaner arrived yesterday and the additional UV curing light for the enlarged post-cure chamber arrived today. That means some of these now-designed components are going to be printed this coming week.
That generated about 2 hours of work modifying everything affected by the prop shaft. I also got a good view of the bulkhead Prop Shaft Seals so I changed them also. The 24" shaft scales nicely to a 1/2" in 1:48 so I could use a standard piece of tubing for it. At 32", it scales to something between 5/8" and 11/16". I'm going with 5/8"… 32" is 20% bigger than 24" so I was able to scale up the spring bearings and their supports. I also got a good view of the prop shaft couplings enlarged its thickness and then scaled it up 120%.
I didn't scale up the MRG's output bearing becasue they wouldn't fit in the space. Instead, I intersected the front face with the new diameter shaft and redrew and edited the parts with the new diameter. It also changed the tapered end and that… was a pain in the butt. As I've said many times before (and it's worth repeating), in SketchUp, it's often easier to draw a part from scratch than to modify it.
The new shafts do look much more massive and, frankly, look bettter to me.
I pause videos that have useful imagery and then do a screen print isolating the parts I want. I did the same with the other video and found some good still images that I didn't have in my reference library. Every image, even if it's just a small detail that is exposed, is worth it.
Shame on me for exporting a lot of these affected parts as STLs and then producing sliced print files. I now have to go back and do some of them over again. I was jumping the gun.
Also, my new Ultrasonic Cleaner arrived yesterday and the additional UV curing light for the enlarged post-cure chamber arrived today. That means some of these now-designed components are going to be printed this coming week.
N4521U
Plastic Pirate
Touch down!!!!!!!!!
