Using Google SketchUp and printapart.com

[Chuck Doan]

Print-a Part has some general guidelines for parts on their website. They don't recommend thicknesses less than .02 for certain things. I am going to send some kind of potential sacrificial part to test the limits in my next batch. Also don't forget some surface sanding may be required to remove the lines created in the process. I didn't find then too troublesome so far, but it's something to consider.

[Fred H.]

Update 3. Elapsed Time = 8.5 Hours
Frustrating couple of hours trying to create the ladder rungs. The 2-D shape isn't hard to envision. The tricky part is where the round rung gets flattened at the ends. Then I tried my hand at putting a round rivet (1/2 sphere) on top of each end. Messy and imprecise. As I am contemplating this further, I'm beginning to think that it might make sense to join the rungs to the uprights and then drill holes where the rivets and or bolts go. Then I could actually pin the ladders to the side of the car. (But, that may be cheating as far as my challenge goes!)

More to come after lunch!

[mabloodhound]

Something to help you in arriving at your dimensions are the Car Builders Cyclopedias.   Many of the older ones are available as a free PDF download on Google.

This page link gives some definitions for your style ladder.   As you will note, the vertical rails are made of wood to which the rungs are bolted to.  http://books.google.com/books?id=Jv7VAAAAMAAJ&pg=PA102&dq=car+builders+cyclopedia+1903&cd=2#v=onepage&q&f=false

The 1903 version is available as a free download  from the American Libraries archives here:http://www.archive.org/details/carbuilderscycl00divigoog
Older versions are available on Google.

A good photo of the car end and ladder is on Page 204 with dimensions.   There are numerous other photos and dimensions in the cyclopedia but it needs to be downloaded as I haven't been able to copy & paste the pictures.
As you will note, the dimensions of the rungs (length) are generally 18".   The spacing between rungs is 14 1/4".   And they are bolted to the wooden vertical sides.

[Fred H.]

Update 4. Elapsed Time = 10.0 Hours

Thanks for the assistance, Dave! I need to check some additional sources, especially as to when the C&S cars were converted from grab irons to ladders. A lot of the commercial 1:24 freight ladders have six rungs. The C&S had five. So, I'm pretty comfortable that my measurements are accurate to +/- 1 inch or so.

Here's the latest progress shots. One end of a ladder rung. (Just need to figure out how to clone the flattened end and get it attached to the rung!) May have to wait until the weekend, though. Work intrudes!

[Frederic Testard]

Sorry for my previous comment, Fred. I thought the ladder rungs were inserted in the sides. I see now that what you want is much more interesting.

[Fred H.]

Update 5. Elapsed Time = 11.5 Hours

Running to catch the commuter train home. Interesting progress in this last session. Check it out:

[JohnP]

Wait a minute- running to catch a commuter train home? Are you doing this on company time Fred?

This is a neat drawing using SketchUp. The detail shaping on the end of the rungs is well formed. I use TurboCad normally and have been frustrated by SU. Your use of many guidelines looks to be a key element in building a part in SU.  Nice drafting.

Plus I leaned about PrintaPart which I may use to master some difficult to model iron castings used in old bridges. And the old Car Cyclopedias are online (thanks Dave).

A fine Friday evening, thanks!

John

[marc_reusser]

Looks good.

You may want to go through and reverse the faces on all the blue parts so they match the white parts. Blue in your SU format/style, is generally used as the default "interior" face.

There are several ways to do this:

1. You can select the entire part (like the rung), then go to the right click menu and select "Reverse Faces"...it should reverse all of them in that part/selection. [Note: if you have a part/section/area that is correct facing in the rung....or when crossing you accidentally select a part beyond, it wil reverse those faces as well.  Using 'components' is often good for things like this because you can merely select the component and it will reverse it...or if doing the selection "within" the component it alleviates the possibility of accidentally selecting something beyond, or "outside" the component.

2. You can select each face seperately, one at a time, and do the right click "Reverse Faces"

3. You can select several faces at once by holding down the 'Ctrl' or 'Shift' key while selecting with the mouse....then do the right click "Reverse Faces".

The only reason I mention this...and it may be a non-issue in the end, since not having tried the STL conversion program myself.......I am merely wondering if having reversed faces could possibly present a problem with the converter in the way it reads/interpolates the model.


John,
SU is super easy to use, especially if you already have a CAD program, and are familiar with using one...and this next comment is in no way meant to make Fred feel bad, or denegrate his great work so far (as he is trying to show how to work and create from within SU, and as a novice to the program).....if you drew a 2D elevation of this in CAD (which only needed you to draw 1 rung, plus center marks for the locations of the rest), plus a plan view of one of each of the different bolt heads...all of which should take at most 60 mins if working at a very leasurely pace....then import the .dwg file into SU.....you could then extrapolate the 3D model from it in no more than 60 mins if working at the same leasurly pace. ....for a total of 2-hrs.  (that is of course sans learning curve.)

[Fred H.]

Update 6. Elapsed Time = 12.50 Hours.

Marc! Thanks for the continued tutorial.

JohnP -- I'm self employed, man! My time is my own money! 

Marc, those suggestions were very helpful. Was wondering about the different colored faces. (How they got that way in the first place remains a mystery.) NOW, I was wondering if I was able to get the rungs snuggled down into the face of the uprights. An extreme close up seems to indicate that I didn't! Wonder how you get components to SUCK UP to each other. (Guess I'll have to offer them monetary compensation, or as in my wife's case, a pair of Louboutin's.)

SU, like any program has some quirks. I like the idea that you view your 3-D rendering as if you were a "camera" and can easily switch views from the Camera > Standard Views drop-down list. HOWEVER, there is no keyboard shortcuts associated with those views! I mean Ctrl-T for top would save me a LOT of time. Plus, putting "Standard Views" on the "Camera" drop-down versus the "View" drop-down is NOT intuitive and takes a LOT of getting used to!

It's interesting that when I was working with the ladder rungs I used the Soften/Smooth edges tool. Not sure I love how it turned out, but it was fun!

[Fred H.]

John,
SU is super easy to use, especially if you already have a CAD program, and are familiar with using one...and this next comment is in no way meant to make Fred feel bad, or denegrate his great work so far (as he is trying to show how to work and create from within SU, and as a novice to the program).....if you drew a 2D elevation of this in CAD (which only needed you to draw 1 rung, plus center marks for the locations of the rest), plus a plan view of one of each of the different bolt heads...all of which should take at most 60 mins if working at a very leasurely pace....then import the .dwg file into SU.....you could then extrapolate the 3D model from it in no more than 60 mins if working at the same leasurly pace. ....for a total of 2-hrs.  (that is of course sans learning curve.)

Marc, no offense taken, you block-head!  Seriously, I probably SHOULD purchase/learn a CAD program and have been meaning to do that for ages. But, the way I have always learned new programs is to tackle a project and  sorta learn on the fly. I think PART of the secret to using SU efficiently is to think initially in 2-D and then lift up the faces. There is clearly "learning curve" time built into the elapsed time calculation. I've found that I can often use a screwdriver as a hammer (rhetorically speaking) and I'm thinking that SU may give me what I need right now to get some parts into production. But, long-term, I may well learn a CAD program, too.

BTW, you guys really are super-nice. Thanks for taking the time to view, comment, and help me as I stumble along. BTW-2, I'm working with a fellow who's probably the leading expert on the C&S. If the dimensions pass muster with him, then I'm gonna assume they're pretty "good to go." -- Fred H.

[finescalerr]

Is the guy you are working with by any chance Derrell Poole? If so, he is a whiz on CAD. -- Russ

[marc_reusser]

Fred,

In the interest of full disclosure, I need to say that I have learned all my programs the same way you are going/go about it..including SU and ACAD, so whatever info I provide came through that process, and there may likely be a quicker way with an LSP/routine to get something done. SU in its original form (and especially pre-Google ownership) is a pretty "basic" program which was intended to be easy and intuitive to use...it still basically is compared to SW or 3D-Studio.....there is now however such a large SU "community" that there are many plug-ins, routines, and programs that were written to do things in SU, interact/work with SU, and allow SU models to be seamlessly exported into them......think of it in a way like Linux for 3D modeling (Kerkythea is another such program but more complex IMO).

SU does have its apparent occasional oddeties/glitches, and they often appear with what seem to be no ryhme or reason, but I have found they are always easily corrected, mitigated or worked around. 

The "blue" is not a true "interior" face it just is intended to denote/differentiate the other side of a plane or surface, however, when extruding solids it is generally (depending on if you push, pull, extrude, and in what direction), the "inside" surfaces of the walls that make up a solid......that like I mentioned is the only reason I was thinking about a potential STL export issue.

I am curious as to why you are using "Camera View" when working on the model.  Camera view is primarily for doing walk throughs or set-ups for that will be exported as a 2D image file or printed.....so that they have the proper perspective and "view".

As far as top/left/right views there is a toolbar for that (which you probably have found)...though the minute you begen to move side to side or along the model, you begin to have a perspective view. What it sounds like is that you are looking for a "fixed" plan/elevation type view of the object......which is as far as I know not possible in the SU model mode/environment......when you get the PRO version, there is another part to the program called "Layout", this is like "paper space" in ACAD....you can create viewports that xref the 3D image into the paper space, and there give you fixed plan and elevation (as well as 3D if desired) views of the model....the viewports like in cad, are also scaleable...IE 1/4"=1'-0".

Here is not-too-clear screenshot image of a basic layout I did for another thread/project here in the forum...the plan drawings are all at 1/4" scale.




...and if I want to I can work within the viewports to change the model.....or if I work on the model in SU, I can then select refresh, when back in layout, and it will update the changes I made in SU...while keeping the views fixed.


Insofar as small gaps and nestling of objects...yes, that can be a PIA at times....especially when you seem to be right on it, but for some reason there is just the tiniest gap. A couple of ways I have worked around this issue are as follows: (using your model as example).

Drawing a center locator mark...either an "+" or a cenreline down the top surface of the 2x2 and then cross center lines on the same surface where each of the rungs is to go. this cross would then allign with the center of the bolt/rivet holding the rung end in place...so I would draw a + on that area of the rung as well. Then in X-ray mode, select the object, use the move command, and for your base-point in the move, grab the center of the '+' on the wrung, and move it to the center of the crossed lines of the 2x2. (You will know you are on the mark by the screen pop-up/indicator).

The other way I have done it is to draw a horizontal extension line from the surface of the 2x2 then select the rung on the end point of the line, then merely shift it horixontally along the line till it's on the 2x2. (this in your case would not be my choice though, as you would then still need to center the rung in the right location, which is dicey and can easily again result in missalignment).

The third and simplest way to do it, is draw a vertical line (perp. to the face of the 2x2) at the center of the rung bolt location, select the rung, use move, once again for your selection point on the move use the center of the bolt on the rung, set that on the endpoint of the perp. line.  Then reselt the rung, again use move, use any point along the bottom edge of the rung tab (the edhe that will be incontact with the 2x2).....and simply move it straigt down along the perp axis, onto the surface of the 2x2.....the screen indicator will let you know when you are there by noting "on surface".


HTH.

Marc

[Fred H.]

Is the guy you are working with by any chance Derrell Poole? If so, he is a whiz on CAD. -- Russ

Russ, it IS Derrell. He's super nice in addition to being a super whiz. I think that perhaps he and I can fill in some gaps in the existing CO-NG space which is WAY over-focused on D&RG, IMHO.

[marc_reusser]

What!...this is for a Colorado car project .....OMG! ...I am going to have to go back and erase all my posts!    ...


Marc
(sorry Fred...kind of an inside joke/issue that Russ, and some of the others that have known me for a while, will get)

[Ray Dunakin]

Very interesting SBS here! I'm considering SU too, as I would love to be able to make use of printapart.com

Marc, regarding the gaps between rungs and uprights... is there any reason you couldn't simply draw the rungs long enough to extend _into_ the uprights a little bit?