Terrance Egolf

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Viewing 15 posts - 1 through 15 (of 19 total)
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  • in reply to: auto trace #43985
    Terrance Egolf
    Participant

    Hey, Dan.

    I suggest you visit the 3D and CAD software forum at Model Ship World, a website hosted by the Nautical Research Guild. Your questions and available options have been discussed there to a great extent.

    I’ve been using DELFTship for refining a ship’s hull plans since 2015 (which involved a lot of research and reconstruction). I’m not aware of any feature in DELFTship for tracing lines plans. That is a function often built into some 2D CAD software (like CorelTrace in CorelDraw), but most CAD programs available to the average modeler don’t do that very well, if at all.

    Terry

    in reply to: Part Import Bug (13.325) #43960
    Terrance Egolf
    Participant

    An update on this problem.

    First, the scaling issue seems to affect the .part import function. I determined this by the fact that when I tried importing parts created more than six months ago—and which imported satisfactorily back then—they now exhibit the scaling problem.

    The precise scaling ratio is 1/3.2808. This is reflected in the object’s z- and x-dimensions, as well as its x- and z-displacements from the model origin. I didn’t test the change in y-dimensions, but assume they show the same issue.

    Hope this will help with troubleshooting.

    Terry

    in reply to: Background Images in v.310 (324) #43941
    Terrance Egolf
    Participant

    Thanks Marven.

    I’ve had the opportunity now to import a full set of views for one of my collaborator’s projects. This new approach is so much easier in many important ways.

    I am promoting your software in the Model Ship World site. I think many modelers will want to use it for refining old plans that are notoriously inaccurate.

    Terry

     

    in reply to: Background Images in v.310 (324) #43937
    Terrance Egolf
    Participant

    OK, I finally figured it out!

    There are two tabs in the Edit window that I failed to see. They are labeled “2D” and “3D”. In the manual, I thought these terms were referring somehow to the main program window, not the Edit window.

    2D-3D

    After figuring that out, resizing and positioning the image is very simple and intuitive.

    I did discover that to update the background image in the main program window, you have to switch views. The image doesn’t resize dynamically with changes in the Edit window.

    Sorry for the confusion.

    Terry

     

    Attachments:
    in reply to: Background Images in v.310 (324) #43936
    Terrance Egolf
    Participant

    By the way, I have two monitors, so that is why the images in the previous post look the way they do.

    —T.

    in reply to: Background Images in v.310 (324) #43929
    Terrance Egolf
    Participant

    Hello Maarten.

    Thank you for your response.

    I think the new Background Images interface is going to work well.

    The problem I am having is when I have added an image using the Open button in the General window, I see this:

    Open-Image-small

    In former versions of the program, when the image is highlighted with the “handles”, you can resize the image to fit between perpendiculars and waterlines, etc., directly in the program window. However, if you attempt to adjust the image by grabbing the handles now, nothing happens. The General/Edit window flickers just like standard Windows dialog boxes do when you attempt to perform another function before closing the dialog box.

    So, when I click Accept in the Background Image General box, I see this:

    Saved-Image-small-1

    The image set in the program window is no longer highlighted and cannot be adjusted.

    It seems that the intent with the new interface is that the user identifies the origin in the new image, aligns the image horizontally, then resizes the image to fit the model guidelines (perpendiculars, stations, waterlines, etc.). I haven’t tried this, but it seems that it would require repeatedly resizing the image to adjusting the number of pixels to fit. Also, since the Resize dialog does not proportionally change width with height or vice versa, it seems you would have to first set one dimension using iterative changes, then adjust the other. Depending on the resolution and size of the base image, one has no idea how much to resize the image.

    It seems that permitting direct manual manipulation of the image in the program window is still the best method to resize background images.

    Again, if I am missing something, please explain, step by step, how this is supposed to work. The manual isn’t clear on process. It just describes what the different functions are intended to do.

    Thanks.

    Terry

    Attachments:
    in reply to: Version 13.10.324 #43920
    Terrance Egolf
    Participant

    I noticed this problem also. My fix was to delete all the existing Stations, Buttocks, and Waterlines and reinstall them using the Tools|Intersections tab. Worked fine after that.

    Terry

    in reply to: Access Violation Error Message When Editing #43757
    Terrance Egolf
    Participant

    Hi Maarten.

    After working in the program for many hours over the past five days, I haven’t had the problem recur.

    I was in the process of overhauling the model of a 19th-century brigantine with lots of curved surfaces I had stopped working on back in August, and so there were a lot of edge deletions and additions as well as switching between surface views.

    Since the program seems to save every change to the model during a session, I thought perhaps I had exceeded the undo memory or some other memory-related issue.

    Thanks.

    Terry

    in reply to: Need a screw? #39223
    Terrance Egolf
    Participant

    Hi iosif.

    I am a retired submariner, so I may be able to answer your question, though I’m not a marine engineer.
    For a given thrust, more blades allows you to reduce shaft rpm. So during the development of the modern submarine propellers, it was not uncommon to see five- or six-bladed propellers. Early subs, due to their limited number of shafts, required much higher shaft speeds than modern boats to attain the required speeds.

    However, other factors contribute to propeller design and the number of blades. The larger the blade diameter for a given shaft rpm, the higher the blade-tip speed, and thus the more likely tip cavitation will occur. Since subs rely on acoustic stealth, cavitation is avoided at all costs with submarine propellers. This is one of the reason the previous generation of subs had large, highly-swept, low-pitch screw blades.

    Finally, the prime-number of blades is a trade-off on maximizing propulsion, taking the other factors into account, and limiting the generation of certain acoustic signals that permit classifying the vessel as a submarine. Going any further than that gets into classified information. Virtually all the major nations with subs today use 7-bladed screws. The next generation of boats are moving to ducted thrusters, to further reduce radiated noise.

    Below is a model I made of a 1980s-vintage SSN propeller, using Blender.

    Blender7-BladedProp.jpg

    in reply to: For beginner #37920
    Terrance Egolf
    Participant

    The information for importing a Table of Offsets is provided on pages 32 – 34 of the manual.

    I had to fiddle with this for several days until I could understand what some of the terms meant and which features to activate and which to leave turned off. During the next revision of the manual, I would like to see a labeled diagram or two explaining the meaning of each of the terms used in this section for the benefit of us nonprofessionals.

    1. “Stations” and “waterlines” are pretty straightforward
    2. While “deckline” would seem to be fairly clear, the example shows the deckline intersections to be above those for the “contour line”, which I assumed was intended to represent the sheer or rail of the hull, so I never used this data.
    3. The “forward contour” is the line describing the stem in the profile view and the “aft contour” is the line describing the stern in profile.
    4. No example is given to show what a “flat bottom” means. Does it mean a horizontal bottom, or a plane surface curved fore and aft?
    5. One thing that I found out the hard way is that every space in the table must have a number in it. If there is no station/waterline intersection in your table, then you must enter a “0.000”. If you don’t do this, very strange things happen!
    6. I found that importing the main part of your table into a spreadsheet makes filling out the required format for DS easy. Then export the spreadsheet as a tab-delimited text file.

    Hope this helps

    Terry

    in reply to: Keel ballast #37895
    Terrance Egolf
    Participant

    Hi Antonello.

    If I were given this problem, I’d probably use the “brute force” method, since I’m a fairly new user myself. Others here might be able to propose something more elegant.

    First thing I would do is create a scale schematic of the ballast. This can be done on paper or a CAD program. Add sufficient stations along its centerline to define its shape. More stations will be needed where the curvature is high. Measure the position of each station from some longitudinal reference point and note these on the drawing. Also find the scale radii of the ballast at each station. I would also find the ratio of all station radii smaller than the max radius to the max radius (Rstation/Rmax). Write these ratios prominently next to each station on your diagram.The reason for this will become apparent soon.

    DELFTShip has an Add Cylinder tool in the 3D Primitives menu. Make the radius of the cylinder the same as the max radius of the ballast. I’d specify enough points to make a smooth cylinder (e.g., 12). The cylinder length doesn’t matter because you are going to delete everything but one circular end surface after it’s created anyway. Set the start and ending coordinate along the DS x-axis and place it at the z-location corresponding to the axis of the ballast in the DS model. The cylinder’s y-location should be 0.00.

    After deleting all points and lines except for one circle, move the circle (a disk, actually) to the position of the max radius station of the ballast in your model along the x-axis.

    Next, select all the edge segments of your circle (and nothing else!) and use the Extrude edge tool to extrude the circle to the first station x-position.

    Then select all the edges and control points of the extruded circle (and nothing else!–I am always forgetting to deselect a random line segment or control point when moving, splitting, or deleting …), then scale them to the scaled radius of that station using the Scale tool in the Transform menu.

    Repeat as many times as necessary for each station in both directions from the max radius station. The ends of the shape can be modeled as very small circles rather than trying to model hemispheres or whatever (this is why more stations are required closer together where the curvatures are highest.)

    You should end up with a fairly accurate representation of a torpedo-shaped keel ballast. If you created this ballast in its own layer. You can turn off the rest of the model while creating it, which will make things easier to see.

    Hope this helps. As I said, this is a pretty crude way of dealing with this problem.

    Terry Egolf
    Greenville, South Carolina, USA

    in reply to: DelftShip update #37841
    Terrance Egolf
    Participant

    For what it’s worth, I have an ASUS DirectCU II GTX770-DC2OC-4GD5 video card installed February 2015. It has the latest Windows 7 Pro OpenGL version. I also have 32 Gb of RAM and I run DS Free in only the High graphics mode. So there doesn’t seem to be any possibility that the problem is associated with graphics data rate.

    in reply to: DelftShip update #37811
    Terrance Egolf
    Participant

    Marven,

    I don’t think it happens by typing a coordinate. It seems to be associated with the pointer dragging the control point. It almost seems like it’s not sure which direction the user is intending to move the point. For instance, I’ve noticed that in the 3D perspective view, there is a location where the 2D point adjustment switches from the Y-Z to X-Z planes, for example, and that seems to be where I’ve had some errors occur.

    Terry

    in reply to: DelftShip update #37809
    Terrance Egolf
    Participant

    I occasionally get a similar message in the latest version when attempting to move a control point. But it’s totally random. If it persists, I save and exit the program and restart it and the problem doesn’t recur.

    Terry

    in reply to: New project: Design a houseboat from scratch #37808
    Terrance Egolf
    Participant

    Wyo, as Marven said, you should start with a blank project and then set up the project parameters (length, draft, beam, etc.) in the Project Settings window.

    From my experience, and I could be wrong, you can’t do anything with control lines until you have created a surface to work with. This requires creating at least 3 more or less co-planar points using the Add Point tool. Then to create a surface, you select all the points that define the corners of the surface (by holding the Ctrl key while selecting each point) and click on the Add Surface button. This action creates an editable surface and adds the edge control curves.

    The DS manual doesn’t go into this aspect of creating a model from scratch. I think the expectation is to import a table of offsets or content created in another 3D program, which from my experience is a much faster way of starting a project.

    In any case, if you don’t have at least a scale sketch of your intended plan to work from, you will spend a lot of time in trial-and-error positioning of points.

    Terry

Viewing 15 posts - 1 through 15 (of 19 total)