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JCL

A beginner starting in 3D printing with Blender - update May 18th - layers

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Thanks for that Andrew, so I'm there or thereabouts.

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Wow Jason another thread to follow. I am also slowly ​dabbling with 3D. Anyone out there using Solid Works! On the subject of 3D printers I was at the Bristol Model Engineering show a couple of months ago. The stand that had lots of people looking at was a local company to Thornbury Reprappro https://reprappro.com/ My son-in-law is considering getting one hence my dabbling. All the best.

 

Keith 

 

Sorry Keith, I missed your post - slowly is the word! The first few weeks are going to be frustrating, so breaks from the software are a necessity for me. that said, I'm still reading the manual and making notes.

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OK, the smokebox continued. Another mammoth post I'm afraid.

 

I've decided to keep the walls at 1.2mm, but I rebuilt the front (again) because I realised that I hadn't left enough room for the actual hinge on the right hand side. It's a lesson to me to not just go by the plans, but to also make sure I look at photos of the loco as well. While putting together the smokebox I've realised that the drawing of the front face is pretty elliptical, so that had to be sorted out as well.

 

This is where it becomes much easier if you name your objects as you go along.

 

Here's what I did to finish the front of the smokebox:

  1. First of all, I redid the brackets, but didn't shape them, so at the moment they are just boxes. As you can see in the top right of the image below, the top rectangle is Top Bracket.
  2. I then copied this rectangle using Ctrl+C and Ctrl+V (standard Windows for Copy and Paste).
  3. I copied the Z axis value (2.30682mm).
  4. I selected the lower bracket, names it and typed -2.30682mm into the Z axis value box. As the smokebox is centred on the Z axis (the centre of the smokebox is where Z=0), the two brackets will be equidistant above and below that line, hence my ability to just use the value and just change it to a negative number.

A quick word here about location values. I believe that Ive found that the location of an object is measured from it's central point. It can be important in a minute, especially when dealing with cylinders.

 

post-14192-0-40712400-1413684845_thumb.png

Creating and locating brackets.

 

Next I had to create the actual hinge, which I did with a series of cylinders. Actually, one cylinder, copied a few times.

  1. I created the long thin cylinder, and used the dimensions boxes to give it a size that made sense.
  2. I pressed the G key (translate or grab) to move the cylinder into place.
  3. I copied and paste the cylinder.
  4. I pressed the G key and the Z key to move the cylinder downwards along the Z axis until its middle point was in the correct place
  5. I then changed the dimensions to fit.
  6. I did the same again, but made the next cylinder a bit smaller and moved it down
  7. Finally I did the same with the top bracket.

post-14192-0-37190500-1413686125_thumb.png

The hinge parts

 

Next I decided to group this hinge to make life a bit easier because, although they line up in two dimensions, I've no idea if they do in the third dimension. That is, they are at the correct height and to the right of the door, but do they actually touch the door? To find out I changed the view so that I could see the smokebox door from the side.

 

As you can see from this side view, they are actually positioned a fair way in front of the door, so that will have to be remedied.

 

post-14192-0-99638900-1413686466_thumb.png

Location of the hinge on the X axis

 

Now I needed to select all of the objects that go together to create the hinge. Now, with that stoking great door behind the hinge this was a hit and miss affair. By naming the parts, I was able to quickly find the smokebox door and hide it by clicking on the eye. As you can see in the red rectangle below, the eye closes when you hide the part. To the right of the eye icon is an arrow. Disabling the arrow will stop you from being able to select that object.

 

I then chose Select -> Bounding Box from the menu in the bottom left. I clicked above and to the left of the hinge objects, then dragged the mouse diagonally down and to the right. In this way I was able to select everything I needed.

 

post-14192-0-43198600-1413687330_thumb.png

 

Finally, I decided that I didn't need the component parts anymore, so with the whole hinge selected, I pressed the Ctrl+J keys to join the parts together.

 

Next, with the side view active, I clicked on G and this time X to drag the hinge backwards so that it touched the smokebox.

 

post-14192-0-74529600-1413689536_thumb.png

 

At this point, you might be thinking, X axis, Y axis, Z axis - how does he know? Looking at the image below, down in the bottom left of the 3D window (where the smokebox is currently sitting) there is a small indicator showing all three axes (1). The X axis is always red, the Y is always green and the Z is always blue. You will also notice that, these three axes are also represented in the drawing itself as thin lines (3), and on the "manipulator" (2) that can be used to move things around. The 3D cursor can also be seen sitting at 0,0,0 (4).

 

post-14192-0-89754700-1413690706_thumb.png

 

I'm worried about saving this post, so I'll do it now and finish up in the next post.

Edited by JCL

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OK, I moved the hinge back so that it touched the front of the smokebox. Also, the rod between the upper and lower hinges also touch the front of the smokebox. Next, it's the brackets. I moved the brackets over so that the right hand edge was exactly in line with the right hand edge of the hinge.

 

As a refresh, to mold the brackets around the door, I did the following:

  1. Select the bracket.
  2. Click on the spanner
  3. Add modifier
  4. Choose Boolean, then difference
  5. Choose Smokebox from the list
  6. Click on Apply
  7. Change the view to see the profile of the smokebox front
  8. In Edit Mode (Tab), click on A to select all the vertices etc of the bracket
  9. Press Extrude then X to pull the bottom bracket outwards along the X axis.
  10. Do the same with the other bracket.

I made sure that the brackets came out less than the plate for the dart.

 

You'll have noticed in the screenshots in this post and the one above that the background image wasn't shown. It's still there, but I took the tick out of the Background Image box to hide it. Now I've to turn it back on and do the last couple of bits. These are handrail holes, and the small knob on the left of the door. To make sure I do these correctly, I'll also have to show the objects created already as a wireframe instead of solid objects. Otherwise I'll not see the drawing behind them. Do this by clicking on the dropdown list immediately to the right of the Object Mode/Edit Mode dropdown list.

 

To create the nob, I did the following:

Left mouse click where I wanted the centre of the knob to bec

Click on Cylinder in the create tab (top left)

Underneath the list of primitives (see an earlier post), there is a section called Add Cylinder which allows you to set up the cylinder's properties (see the red box). Just choose appropriate values, and you're there.

 

post-14192-0-52791500-1413692556_thumb.png

Cylinder properties, with the cylinder enhanced for this post.

 

Actually, I'm good in 2D, not so good in 3D, so I then rotated the view, and used the side view to work out the length of the knob.

 

I was going to add handrail holes, but I've noticed that the handrail on the smokebox door could be in one of two different positions, so I've decided that, as it's easier to add something than take it away, I'll leave it there. Below is the front of the smokebox as finished. Next time, I'll be extending the walls backwards and putting the chimney on top. There are going to be two smokeboxes as one was longer than the other, so I'll have to remember to be careful with my file naming. I think next time I'll also look into creating assets that can be used in more than one file - like a library of parts as mentioned by Mike in post #18

 

Anyway, here we go - one smokebox door. It only took me about 5 hours all in. Good job I'm not being paid by the hour!

 

post-14192-0-66513800-1413696794.png

Edited by JCL
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Hi Jason, you can change the ambient and background render colours to make the image lighter :) but looking really good. You have inspired me to have another go with Blender.

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Thankyou, I'll give it a go. :)

 

I think it was Mike who mentioned about changing the file name from time to time so you have a position to fall back to if everything goes horribly wrong. This stood me in good stead yesterday when getting the smokebox door as progressed as it is now. My naming is D3 smokebox 1.blend, D3 smokebox 2.blend, D3 smokebox 3.blend, etc. I save under a new name as soon as I've completed something difficult, or if I've done a fair bit of work. My view is that I will save under a new filename when I get to the point that if I lost the current file I wouldn't have too much rework to do to bring a previous one up to the current level.

 

So yesterday I was building the smokebox front, and I came to export the file. The brackets and hinge were the right size, but for some reason the smokebox door measured 2 metres in diameter. The whole thing looked right on screen, so obviously there was a glitch in the file somewhere. Shapeways also seemed to think that the file was 2m in diameter. To get around this, I simply went back to a previous version and reworked it. The only good thing about it was that the rework was a lot faster than the original build as I pretty much knew what I was aiming for and how to get there.

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I've a few tests to do with the Silhouette tomorrow for someone, but in the meantime I've spent this evening checking the door and trying to work out how to upload to Shapeways. I've finally worked everything out, so later in the week I'll do a step by step run through on what I did. In the meantime, here's the end result: https://www.shapeways.com/model/2778597/lner-d3-d4-smokebox-front-4mm-scale.html?li=aeTabs

 

Tom, please feel free to remove the link if you think it inappropriate.

 

Smokebox Door Issue on Shapeways

 

Edited to add that the first smokebox door I put up on Shapeways had a material thickness error on the top bracket. I've found that this was caused by creating and editing the size of the bottom bracket, then copying it and moving the copy to the top bracket position. When I created both brackets from scratch I didn't get this error.

 

Cheers

 

Jason

Edited by JCL

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Well done Jason, the first steps have been taken. No worries about the link.

 

I am following your journey with an attempt of my own and am sure you have inspired others so keep up the good word and I'm looking forward to more.

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Shapeways

 

I thought I'd cover Shapeways this time. I've had an ID with them for a few years, but until now all it's been used for is to send me emails about their services. I've never bought anything from them or made anything to upload to them. I won't go into detail about setting up an account, it's a pretty standard process.

 

The next thing I did was upload something, I'll cover this in two steps; creating the file to upload, and actually uploading the file into Shapeways.

 

Shapeways can import a number of different file types such as STL, OBJ and DAE. I'm interested in the STL file type as I can export to this type directly from within Blender. To create an STL file I do the following:

  1. Hide the elements that I won't be exporting (this is just me, I want to make sure I'm only exporting what I need) by clicking on the eye that is displayed against every object in the top right-hand corner of the Blender screen.
  2. Press A once or twice to make sure I select everything that is left.
  3. Click on File, then Export, then STL.
  4. Choose a file name and location, and that's it.

I have noticed that Blender will only export selected objects. If It ain't on the selection list, it ain't coming in!

 

To upload the new .stl file

  1. After you have logged in, there's a smiley face in the top right-hand corner, click on it, then click on Models.
  2. You will see a list of models you've already uploaded (probably none at this point if you're like me), and in the menu at the top in light blue there is an option to upload. Click on this.
  3. You will see a form called "Upload your 3D design". Click on select a file and go hunting for your STL file you created just now.
  4. Set your model units. I set my units to mm in Blender before I created my model, so I chose mm at this point. If you don't get this right, your model will come out the wrong size. If you get a message saying your model is way too big, then this is probably the cause.
  5. Click Upload.

Shapeways will now upload your file. You can see in the first image that I forgot to create the curved base. I did this and then clicked on the Update File button. You need to choose your measurement units again for the updated file. I've added information under each of the following screenshots.

 

post-14192-0-29152400-1413877186_thumb.png

 

In the image above, just above the name of the model, you can see the upload button, click on it, then locate the STL file you just created, then choose the measurements units of your file. This should be the same as the measurement units you set up in Blender before you started your model. As you can see, there is no cm option, which is why I used mm in Blender. You will also see below the chimney render the list of possible materials in a table. If your walls are too thin, it will be shown in that table. You can choose to allow Shapeways to "fix" your model. I use this screen to see where the issues are and then go to Blender and fix them myself. I'm always wary of automatic fixes. Use the "Update File" button to update your fixed STL file. Finally, if you change the model name at this point, remember to press the save button.

 

post-14192-0-92298900-1413877198_thumb.png

 

Once you are happy that your model is probably ok, then click on the Details tab between the Models and Selling tabs. Add your information here. Provide a description and a good object name that will help people find your object when they search Shapeways. Also choose the appropriate category or categories for your model.

 

post-14192-0-40707600-1413877211_thumb.png

 

Also add tags like you do in RMWeb to further increase your object's chance of being in search results. You can also see the Material Render Pose. Sometimes models are imported on their side or showing their backs. Use the options to the right of your model's render to make sure it's facing the right way around. The pose will then be used to generate renders of the object in different materials. Again, if you change the model name at this point, remember to press the save button.

 

post-14192-0-21129800-1413877221_thumb.png

 

Clicking on the Selling tab, you can decide whether or not to sell your model to the general public. Remember to tell them the scale you are working in. I know OO is a gauge and not a scale, but add this too as a lot of people would search on that. You can also choose whether or not you want your model to be public or private.

 

post-14192-0-58053100-1413877232_thumb.png

 

Further down that page you can choose whether or not to put your model into BETA. That is, show people that you are happy to sell it to them, but they should be aware that it might not yet be 100% perfect. If you have a print made for yourself, and you are happy with it. It's best to remove the BETA tag as soon as you can. You should also choose the materials you want to sell your model in, and provide a total price including your markup if you want to make some money off it. Once you have chosen some materials, you can change the default material for your object. If there aren't any default options and you have chosen your materials, click on the Save button and refresh your browser window (F5 on your keyboard).

 

post-14192-0-91306200-1413877245_thumb.png

 

And that's it. Obviously if you intend to sell your model with a markup you need to open a shop on Shapeways. The easiest way to do this is to follow these instructions https://www.shapeways.com/tutorials/open_shop/ . If your computer screen is large enough, it's worth having the instructions in one half of the screen, and the Shapeways site in the other half. Either that or you can print them off. Objects you have created should automatically be added to your new shop if you have ticked the "Offer For Sale to Others" box.

 

I hope that this helps.

Edited by JCL

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I couldn't sleep last night - too much coffee too late in the evening to help me get home from picking my wife up from the airport. So while I was blog upright awake I had a trawl of the internet (it doesn't browse itself you know) and found a free beginners book on Blender. It's not 3D printing specific, and you'd probably only be interested in the first half, but it is clear and succinct, and very easy to follow. When you consider the prices of commercial books, this PDF is good value. It'd be worth printing some of the pages off, such as the shortcut/hot keys.

 

http://www.cdschools.org/Page/455

 

p.s.If you really want to make if difficult for yourself, it's also available in Russian. :)

 

p.p.s unless you are a Russian speaker.

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thank you so much for doing the leg work and letting us follow, it makes life much easier for anyone 'following' you. Hopefully your silhouette cameo cutter work will allow you to move forward at a good pace. 

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Hi Jaz, good to see you! I'm enjoying myself at the moment! :)

 

How I see it is that there are two ways of doing this. The first is to get Shapeways or other 3D printer to print the whole thing, or to just get them to do the bits that are difficult. "Difficult" is in the eye of the beholder of course. One thing I have been thinking about is the flared tender top. A mare to do with styrene, but easier with 3D printing. My Idea would be to create just the tender top, including the flare, and then bend some styrene for the tender sides. I could add a lip on the inside of the flare so that the sides have something to butt up against. Could be interesting! :)

 

Next up will be a slightly more involved setup before I start the loco proper as I'll have two reference plans; one from the front, and one from the side. I'll need to make sure that these plans are exactly the right size, and I'll also include a photo of the engine that I'm actually going to model. It'll be one that I have photographic evidence for it being in Skegness in the 1920s. As I said before though, I'm going to try to make the engine modular so that other variations can be made. Over on the Wainfleet thread, when I first mentioned this it was suggested that I grab a Hornby Railroad GWR County class 4-4-0 loco for the chassis, which I have. The wheelbase for the tender is pretty close as well, which is a bonus.

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I'm going to have two views open now, one a front view, and the other a side view. In each view I will have the corresponding elevation that I will import into the workspace as background images. I was going to give you a blow-by-blow account of how I created this split view, but the video below does a much better job:

 

 

So watching this, you should be able to split your workspace into two separate views by clicking and dragging the diagonal lines shown in the red circle. When you do this, you must remember that you are looking at exactly the same model, only from two different directions. This means that any changes you make in one view will show in the other view.

 

I've found that the panel on the left of the screen is called the Tool Shelf, and you press the T key to toggle its visibility. The panel in the middle is the Property Shelf, and so obviously you press the N key to toggle it's visibility. Each of the split views has its own Tool Shelf and Property Shelf. In the image below, you can see that the Tool Shelf for the right hand view is currently invisible, but the Property Shelf is visible.

 

To show or hide the appropriate Tool Shelf or Property Shelf you just move your mouse over the view you want to reconfigure and then press the T or N key. You can move the grooved line between the two views from side to side if you want to temporarily make one view bigger.

 

post-14192-0-26908100-1413928272_thumb.png

 

You will also see the long red box at the bottom. Each view also has it's own bottom menu. This means that you use the left hand menu to change the left hand view, and obviously the right hand menu to change the other view. In the image above, I has used the left hand bottom menu to change the view to Ortho View, and also changed the view to display the front of the loco. In the right hand view I again changed to Ortho View, and this time I decided to show the view of the right of the model-to-be.

 

After setting up these views and the measuring system (see the red box on the right in the above image), I then imported the background images using the options boxed just above the lower menu. I can't assume that these images are both to the same scale, even if they came from the same file. To make sure they are the same size, and the right size, I did the following:

  • I scaled the side view first because I know the loco and tender together are 52' 2 3/4" long. In 4mm scale, this works out to about 208.92mm or 20.892cm. So, using the method in the previous post, I resized the image using the scale input box. In my case the scale on the side drawing was 104.6.
  • I made sure that the drawing crossed the Y axis at zero in the middle of the smokebox door dart as I knew I would be able to see the dart in both views.
  • I then created a cube and resized it so that it was the same height as the loco from the rails to the top of the chimney.
  • The cube shows in both views, and showed me that the background image in the front view was too small. This time I didn't need to work out the size it should be, I could just change the scale of the front view until it was the same size as the cube as well. This time, I made sure the smokebox dart crossed the X axis at zero (this is the red horizontal line in this view).
post-14192-0-20759100-1413930429_thumb.jpg

 

So now I have my two views. I have background images showing the loco in two different directions, and I know that if I draw a boiler in one view, it will be exactly the same size in the other view, and will cover exactly the same amount of the background image.

 

My final action is to include a photo of the loco I want to reproduce. This will be used for checking only, and won't be a part of the modelling. To provide a niche for this:

  • You need to right click on the line marked with an arrow in the image below, and click on "Split Area".
  • You then move the mouse the the right. A horizontal line will be displayed. Move it towards the top of your free space.
  • Now you will see a panel similar to the one above it. You need to change this panel to UV/Image Editor. You do this as shown in the second image below.
  • Hover the mouse over the new panel, then press Shift+space This will expand the panel so that it is the size of the whole screen.
  • Find your reference photo and load it into your window.
From now on, hovering over the bottom right of the screen and pressing Shift+Space will display your reference photo in full screen mode. Pressing Shif+Space or clicking on the "Back to Previous" button will take you back to your main view. This is great as all of your files and references will be available to you from your main screen without you having to go hunting for them,

 

post-14192-0-44245100-1413933071_thumb.jpg

Splitting the bottom of the right hand panel by right clicking on the line shown by the arrow

 

post-14192-0-33416500-1413933091_thumb.jpg

Converting the new panel to an image viewer

 

post-14192-0-22919100-1413933103_thumb.jpg

Adding the image

 

post-14192-0-88348600-1413933322_thumb.jpg

Viewing the image in full screen mode. Use your middle mouse wheel to zoom in and out of the photo.

 

Note that my background images slipped, so after taking the screenshots above I moved the background images back into place.

 

Once you have done all that, grab yourself a beer or other beverage of your choice. And don't forget to save your file! At this point, I'll be making two copies of the file D3 main 1.blend and D3 main 2.blend. I will leave the first file as a back-up, and just use the second file for the next stage.

 

This post might be a bit much. If anything is unclear please don't hesitate to let me know and I'll clarify the actions I've taken.

Edited by JCL

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I've decided to add a boiler to see how this workspace layout will help me in practice.

 

To do this I made sure the tool panel was visible in the left view showing the side of the loco

I made sure that the 3D cursor was at 0,0,0

I clicked on the Create Tab, then Cylinder to create a cylinder centred on 0,0,0

Obviously the cylinder was not going to be the right size, and certainly won't have the right number of vertices, so I used the input boxes under the Add Cylinder to bump up the vertices to 100, to change the radius to 1cm, and to change the depth (the length of the cylinder) to 6.06cm,.

Next I used the location and rotation values to move the boiler to the right location over the drawing. Because in the front view the centre of the front of the loco is bang on 0, I know that the boiller's centre on the x axis will be at 0 as well, so it's a value I don't need to worry about.

 

As I move and resize the boiler I can see it changing in both views at the same time. This is telling me that everything appears to be OK.

 

A couple of notes about cylinders and spheres. I've noticed that the Add Cylinder properties are only available in the initial setup stage. If I use any method other than the input boxes to change the object's location or size, then the Add Cylinder properties panel disappears. Note that it is only in the initial setup stage for the cylinder that you have the ability to change the number of vertices so you can smooth out the boiler surface.

 

post-14192-0-13192200-1413936271_thumb.jpg

 

The image above shows the following:

  1. The cylinder properties available on initial setup.
  2. A circle with red and blue lines emanating from it - the scale manipulator. Clicking on a square on the end of a line will increase the size of the object in that direction. It's the same as pressing for Scale and then Z to only rescale the object on the blue Z axis.
  3. A circle with a green arrow and blue arrow- the translation (movement) manipulator. Clicking on the arrowhead and dragging your mouse will move the object in that direction. It's the same as pressing G for grab or translate, and then Z to move the object along the Z axis only.
  4. Finally, each view has a few buttons in the lower menu that allow you to change between translate (move), scale and rotation manipulators.

This was just to make sure everything works as expected. I'll be deleting the boiler now, and the next thing I'll do is that curved running plate. Not today though!

 

cheers

 

Jason

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Jason,

 

If it's any help on designing the breakdown of parts for a complete loco, rather than actually designing the parts, Brian Madge has a blog on how he does this on his website at http://www.madge00n3.co.uk/3DPrinting/3d01.htm.

 

I'm reading your posts with interest, but not yet following you in trying out Blender.  However, I might need to do this for my French Tramways of the Correze and Paris, Orleans, Correze locos, as there are no parts available in 1:55 scale - I have been thinking I would have to scratchbuild them from metal, but .......?    I've been amazed at the speed with which you have come to grips with the program.

 

Mick

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Thanks Mick, that's a very interesting website. I've just skimmed it and I'll definitely read it properly this evening in front of the fire.

 

  I've been amazed at the speed with which you have come to grips with the program.

 

 

 

I suppose I'm at a slight advantage because I am ex-IT and I've worked with computers since the old ZX-81 (with 16k RAM pack, but not the printer - we weren't made of money!).

 

A lot of people have said that Blender has a steep learning curve, and it has, but as 3D modellers, we would only use a small proportion of what the software has to offer. I'm certain I won't be adding textures and animating parts! With clear instructions you can do practically anything. The problem is that, until now, apart from Paul Hobb's great work for the train sim community, there isn't really much to go on for railway modellers, especially in 3D printing - how do you create a flared tender top in Blender? I'll be finding out a bit further down the road.

 

The steep learning curve is one of the reasons why I have resisted trying Blender in the past. I've installed it a few times, looked at the interface, decided there's too much information on the screen, and given up before I've even clicked on the mouse! Open-source software is also not known for its user friendliness or easily accessible manuals. Reading around Blender, I've noticed that a lot of people are saying that the interface has been through a huge revamp, and it's a lot more logical than before. I can only take their word for it, but there does seem to be consistency about how things are done, and the manual I found on that college website does a good job.

 

I have a background in back office IT, and there are some truly horrifying systems out there. The worst kind of systems are the ones that are either not logical at all, so you can never get a proper grip on them, or, systems that regularly crash. When that happens the software is deleted from my hard drive pretty quickly.

 

I generally plod on with what I'm doing, and I try not to get frustrated with software. I constantly make copies of my files as insurance so that I can go back to any point and start again. I've been down a few dead ends writing these posts, but each time this has happened, I've learnt something new. Sometimes it's that what you are trying to do is impossible, other times you learn a new way of doing something that isn't usable for the task at hand, but might come in useful later.

 

The worst thing one can do is to work angrily. You should never feel like you are fighting the program. If you do feel like that, eventually you will give up on the software completely. If I start to get too frustrated, I will go grab a tea or coffee. I might not go back to it for a while, I may mull the problem over, or watch some Youtube videos to see if I can find a solution. For example, the setting up the workspace post I put up yesterday was from information in an hour long Youtube video about building a Porsche in Blender. I couldn't work out what he was doing in one bit, so I found another video to fill in the gaps; that video I put up in the post. I only watched the bit of the Porsche video I needed - it's here if you want to see it https://www.youtube.com/watch?v=o9STM6bje9Y .

 

When I get back to the computer, I give whatever I'm doing another go, and if I still can't get it to work, then I'll find a forum and ask other people how they got it to work. There are a lot of Blender forums out there, and many with beginner sections. A quick scan of a forum will tell you how friendly they are. If they look likeable, I'll post up a question providing as much information as I can, including the version of Blender I'm using, and the precise nature of the problem. I'll always thank them as well. I read a Rail Sim threads in gthe last couple of days where someone was asking a question, he didn't like the replies and all but called them idiots for not understanding what he needed! He didn't get very far. That's the great thing about RMWeb, people are (in the main) really very nice and will help you if they can.

 

As always, with these posts, if anyone needs any more detail, if anything at all isn't clear, or if I have made a mistake at some point, please let me know, I'm happy to go back and edit the previous step-by-step posts to make sure that everything works properly. I'm also happy to take in information as well, as, although I'm not exactly working in the dark, it's still early dawn, and I'm still liable to trip up from time to time.

 

On that note, best I go make myself a cuppa.I've a dog to wash and a house to clean (not because of the dog).

 

cheers

 

Jason

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Hi there

 

I've not done any modelling today, but I have tidied up the spreadsheet that I use to calculate my measurements. As you can see in the image below, you type in the feet, inches and fraction, the spreadsheet then calculates the total number of inches, before converting it into mm in your chosen scale. It then uses the initial scaling factor and measured value in Blender to tell you what the actual scaling factor should be. When you have that, you know you are drawing the model at the correct size for your chosen scale.

 

To get a scaling factor, you do the following:

  1. Set up your measurement system in Blender - Metric and Scale = .001 if you are using millimetres.
  2. Type into the first three columns a known measurement on your paper or digital plan, say the length of a loco or the height of a building. Try to make it one of the longer measurements for greater accuracy.
  3. Now, in Blender, use the ruler to measure the value of that same measurement. Type this into Ruler Measurement.
  4. Type in the Initial Size as per the value in Size box the Add Image panel. This is usually 5.
  5. The New Size will be calculated. You can copy this value using Ctrl+C and paste it into the Size box in Blender.
  6. Finally, check again with the ruler to make sure your background image is sized correctly and you are good to go knowing that the image is the right size for the scale you are modelling in.

post-14192-0-86952300-1414016427_thumb.jpg

 

I have created this spreadsheet in Excel 2013, but I can save the file in the older Excel format, and in OpenDocument Spreadsheet format as well, which I'm assuming can be used in Open Office. I can't test these in the relevant software, but I'm assuming they will look pretty similar.

 

If you are not using Blender, you can obviously use the mm column for measuring by hand.

 

If anyone wants a copy of this file please send me a PM with your email address in it and the version of hte file you would like (xlsx for newer Excel spreadsheets, xls for older spreadsheets, ods for Open Office). My computer has a virus scanner, but feel free to scan it yourself before you use it. Please let me know if it works ok for otherwise or you.

Edited by JCL

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I saw Rabs had done a police box and 3 daleks......in OO......with his 3d printer..... :angel:

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I saw that :) He's done some great stuff in his thread.

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As a follow on from the spreadsheet, if you wish, you can copy the three formulae that matter into an empty spreadsheet as follows:

 

D9: =IF(B9*12+C9+D9<>0, B9*12+C9+D9,"")

E9: =IF(E9<>"",E9*($C$4/12),"")

I9: =IF(E9<>"",IF(G9<>0,IF(H9<>0,H9/G9*F9,"Type in Initial size"),"Type ruler value"),"")

 

Only copy the characters from the equals sign onwards to the right into the cells identified as D9-I9.

 

These formulae depend on the fact that:

  • C4: is your scale value expressed as the number of mm per foot.
  • B9: is the feet portion of your measurement
  • C9: is the inches portion of your measurement
  • D9: is the fraction of an inch portion of your measurement
  • G9: is the measurement you took in Blender using the ruler tool
  • H9: is the initial size value in the Background Image pane

All of the values in row 9 can be copied down as many times as you like.

 

cheers

 

Jason

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I did get 15 minutes in to do a couple of things, and had a Eureka moment on the way.

 

If we go back to the fillet/flange/flare on the bottom of the chimney, you'll remember that I wasn't 100% happy with how I was doing it. Well I haven't automated the process, but I have tightened up the surface of the flare.

  1. I created the chimney in the normal way using a profile and spin.
  2. I then made the flare as described in a previous post by moving the smokebox up so that the top of the smokebox kisses the bottom of the flare.
  3. Then I went into Edit mode and moved the outer/bottom layer of vertices down so that they touched the boiler.
  4. Next I moved the other vertices down to keep the shape of the flare consistent.

So far so good. I've covered this already. I wasn't so keen on the smoothness of the flare I did on the latest chimney, so I had a look around, and through trial and error found a way of smoothing everything out.

  1. In Edit mode, I used Select -> Circle Select to select all of the vertices except the top and bottom "rows". (see the image below)
  2. Then click on Smooth Vertex (boxed in the image below).

The non-selected vertices act as anchors as the program moves the vertices up and down slightly to smooth out any rough points in the flare, making the end result much smoother.

 

Although this still has the manual component, it actually takes less time because you don't need to constantly go around and around minutely moving the vertices up and down to try to get as smooth a surface as possible. Sure, you have to be there or thereabouts, but, well I'm chuffed (as it were).

 

post-14192-0-81383000-1414027527_thumb.jpg

 

cheers

 

Jason

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One of the things I struggle with 3D modelling is whether I should be doing solid modelling or whether I should do mesh modelling. As I have never/not printed anything and so far have just been fooling around and haven't made anything to print would be interested to hear from other what is the best method for this? Like the Porsche vid Jason there is so much stuff on Youtube but as you say there is little for the railway modeller.

Tom

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Hi Tom, what do you mean exactly by solid modelling?

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Jason, what I mean is either taking a primitive i.e. Cube and then forming into required shape as opposed to taking a plane and manipulating that to required shape. If that makes sense..

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It doesn't really make too much difference in Blender what you start with.  I think it is more important to get started - pick something relatively simple which you can finish reasonably quickly and get printed.

 

What you will tend to find is that certain starting points are easier for certain shapes eg square and boxy end result  probably start with a cube.  Circular or cylindrical start with a circle etc. You tend to learn what works best with experience - some stuff that I drew when I first started I would draw differently now that I have more experience.

 

I've been interested in Jason's use of measurement units in Blender - I draw everything with 1 blender unit (they are not really specific measurement units) = 1mm of the model.  Then when I upload to Shapeways I just need to tell them that 1 unit = 1mm.

 

Cheers, Mike

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