Steam Powered Deck Winch

Steam Powered Deck Winch
3dwarehousemodelI found the Liberty Ship Steam Powered Deck Winch by Greg O on 3D Warehouse. I will be using this as a ‘guide’ .. reworking it to create one of my own, based on but not a copy of this model.

Note: The purple in the drawing are areas that have the faces flipped (this is an indication of inside faces). Looks to me like he got this far and said the heck with it and just uploaded the file. That’s fine. I have photos of the same winch on a Liberty Ship. I am not in ANY way concerned with making a exact copy .. my ship is dated decades before the Liberty Ship era but this will serve as I said, a guide for my own design.

Following, I am going to cover the modifications I have made .. no rhyme or reason .. in part based on photos of a similar if not exact winch found on a Liberty Ship. Horray for Google search.

There are two elbows running off of the steam chest(?). Let’s look at them first.

elbows_originalHere we can see them as downloaded and at first look they appear fine .. other than some reversed faces by that is a minor problem.
The Real Deal
elbowsLooking at a photo of the elbows we can see that the modeled version has too much arc. The actual elbows are short and stubby when compared to the model. While not that big a deal .. compared to say Global Warming but can be fixed non the less.
Some Dimensions
elbow_dimOn the left is the original elbow. Dimensions are in mm. On the right is my modification. I made the collar larger, increasing the step from 0.066mm to 0.100mm – this being the minimum detail possible with FDP (Frosted Detail Plastic) from Shapeways. This increased the collar diameter from 1.058mm to 1.126mm. These are small numbers – that is a 0.002″ increase in diameter. The radius for the 90° bend was reduced from 1.191mm to 1.028mm. Again, not much – about 0.006″ and you may wonder why go to the trouble. Well .. visually it does make a difference and honestly since I need to re-work the mesh so I am not copying the original (that would violate several agreements on downloading and then printing the file) why not make it as best as I can? Takes no longer to do that then to make it ‘wrong’. I also have to adjust the mesh so it will print correctly. That I suppose is the prime reason for a redesign.
From 2D to 3D
elbow_3dOnce I had the “New and Improved” elbow I could then turn that 2D drawing into a 3D model. A plugin called Curviloft is used to create the elbow from to circles and a path .. “Create Loft Junctions following a given path”.
elbow_comparisonHere we have the original elbow on the left and my version on the right. In detail not that big a change but all of the small changes will accumulate over the entire model.