So you would output your final object to another program for scaling? What other programs would you use?

Scott Haycock

Don't know if this will pertain using Sketchup...

I design in 1:1 because I work from prototype drawings. When I'm satisfied with the part or assembly I <Save as> an STL file. Also 1:1. I bring that into Netfabb and scale it, and export *that* as another STL file. (I have to use the export function with Netfabb - for some reason I can't get it to <Save as> in that program.)

I find I get a higher quality output if I scale the STL file rather than scaling the design and then creating the STL file. (I tend to lose my curiosity when I find a system that works and will just stick with that.)

Tom Madden

So you would output your final object to another program for scaling? What other programs would you use?


Scott Haycock
Modeling Tarheel country in the Land of Enchantm ent

yes - but if using Sketchup to scale the drawing to HO, you can also run into the 6 decimal place rounding problem if you are not careful. Dividing most large numbers by 87.1 seldom produces neat 6 (or fewer) digit quotients. Using other software to scale a full size drawing allows one to get around that problem. But drawing with the rounding problem in mind from the get-go is also worth some effort.

Rob Kirkham

--------------------------------------------------
From: "Scott H. Haycock " <shhaycock@comcast.net>
Sent: Friday, February 08, 2013 6:18 PM
To: <STMFC@yahoogroups.com>
Subject: Re: [STMFC] Re: 3D printing challenges etc.

Rob
In Sketchup, c an't you draw in full scale then reduce the final result at the end?


Scott Haycock
Modeling Tarheel country in the Land of Enchantm ent
----- Original Message -----

Rawil Ismail wrote:

Tony, did you try the "See original listing" link? From that linked page, I was able enlarge the photos.

Yes, thanks. I was fooled by all the images "more from this seller" and did not scroll down.

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@signaturepress.com
Publishers of books on railroad history

Tony, did you try the "See original listing" link? From that linked page, I
was able enlarge the photos.

Pete Ismail
Peyton, CO

On Fri, Feb 8, 2013 at 7:15 PM, Anthony Thompson <
thompson@signaturepress.com> wrote:

**


Tim O'Connor wrote:

http://www.ebay.com/itm/111007867594
http://www.ebay.com/itm/121060850109
http://www.ebay.com/itm/111007867635
http://www.ebay.com/itm/111007866997
http://www.ebay.com/itm/111007867546

Since bidding has ended, or the item sold, in all five cases, you can no
longer click to enlarge. Not many of us can identify much in the little
thumbnails provided for buyers to look at.

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@signaturepress.com
Publishers of books on railroad history

[Non-text portions of this message have been removed]

Rob
In Sketchup, c an't you draw in full scale then reduce the final result at the end?


Scott Haycock
Modeling Tarheel country in the Land of Enchantm ent

Tim O'Connor wrote:

http://www.ebay.com/itm/111007867594
http://www.ebay.com/itm/121060850109
http://www.ebay.com/itm/111007867635
http://www.ebay.com/itm/111007866997
http://www.ebay.com/itm/111007867546

Since bidding has ended, or the item sold, in all five cases, you can no longer click to enlarge. Not many of us can identify much in the little thumbnails provided for buyers to look at.

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@signaturepress.com
Publishers of books on railroad history

very nice parts Tom! The detail you are able to draw with solid works is impressive.

Rob

--------------------------------------------------
From: "pullmanboss" <pullmanboss@yahoo.com>
Sent: Friday, February 08, 2013 12:50 PM
To: <STMFC@yahoogroups.com>
Subject: [STMFC] Re: 3D printing challenges etc.

Mick Storzek wrote:

It all goes back to the mantra I've been chanting...

I can't get no
RESOLUTION,
I can't get no
RESOLUTION,
But I try, and I try, and I try...

Until the process can reliably yield .003" steps on the surface, and reliably construct smooth vertical walls, I just don't see much use for it. I keep seeing people singing the praises, but I'm not seeing any photos of the actual models, just overall photos of frosty white blobs.

OK, here's some photos of that parts plate I mentioned yesterday. It was designed 1:1 in SolidWorks 2012 and saved as an STL file. The STL file was scaled to 1:87.1 and validated in Netfabb, a free viewer available through Shapeways, and sent to ADC manufacturing. ADC created the part using 3D Systems Projet process in 29 micron layers at 750 x 750 DPI resolution. (Shapeways calls it their FUD process.) No white blobs because I hit it with a light coat of gray primer so I could make a mold. Photographed in direct sunlight to accentuate every detail, defect and dust particle. These two photos show the whole plate from two different angles:
http://pullmanproject.com/Plate1.jpg
http://pullmanproject.com/Plate2.jpg

Here's the center portion in extreme closeup:
http://pullmanproject.com/PlateCloseup.jpg

In this photo you can see a heavy wax track below the drain valve housing on the bottom of the left unit. You can also see the general roughness of the vertical surfaces. But that sheelmetal flange running the length of the middle unit is 1/2" thick - 0.006" in HO, and perfectly defined. (It projects 1".) Likewise the rivets at the top edge of that unit are 1/2" in diameter and nicely defined. But most impressive is the lack of stairstepping on the angled faces of all three housings.

I did nothing but clean and prime that plate. I polished out the wax tracks and cleaned up the first generation castings, and those will be my production masters.

Tom Madden

Anyone know of any HO or N scale decals that contain a Watch Your Step warning in white? I had a set of old Walthers with this for a caboose but naturally ruined one of the decals. Many of the decal providers don't have photos.

Thanks,
George Courtney

Dennis has basically nailed the source of my difficulties. Better software is the obvious solution, but for now I'm getting sufficiently good results with free software (Sketchup) that I am instead working to improve my drawing skills. For example, early on I was using conversions from prototype dimensions to HO scale dimensions that used all 6 decimal points available in Sketchup. "Wow - can I draw with precision" I thought. Dumb beginner mistake. As a result, the software couldn't handle dividing a space in two equal parts as it would require the 7th decimal place. Seems self-evident now, but I didn't catch that in my early on line learning efforts. Given the resolution of the printed product, nothing was being achieved with 6 decimal places that couldn't usually be achieved in 3 (and sometimes 2) places.

Rob Kirkham

--------------------------------------------------
From: "soolinehistory" <destorzek@mchsi.com>
Sent: Friday, February 08, 2013 8:46 AM
To: <STMFC@yahoogroups.com>
Subject: [STMFC] Re: 3D printing challenges etc.

--- In STMFC@yahoogroups.com, Richard Brennan wrote:

At 09:57 PM 2/7/2013, Rob Kirkham wrote:

That too is too subtle with 3d printing.

So I've drawn and re-drawn it - and each time come to a leaky dead end.
When I get the interest back, I'm going to start from scratch and do it again.

I suspect the issue is NOT your drawing...
but the specific 3D print process/technology you are using.

Question - Were you expecting finished models to be:
1st generation: 3D print each car + paint + lettering?
2nd generation: 3D print master car car + resin-cast copies + paint +
lettering?

If the latter... then the need for 3D print quality trumps the desire
for a low cost print,
and you can find a print service that will do the resolution you
need. They do exist!

Just a thought...

--------------------
Richard Brennan - San Leandro CA

It all goes back to the mantra I've been chanting...

I can't get no
RESOLUTION,
I can't get no
RESOLUTION,
But I try, and I try, and I try...

Until the process can reliably yield .003" steps on the surface, and reliably construct smooth vertical walls, I just don't see much use for it. I keep seeing people singing the praises, but I'm not seeing any photos of the actual models, just overall photos of frosty white blobs. I'm sure one of the various additive processes will eventually yield good, usable parts... but whether we will be able to afford them is another issue.

Rob's file problems seem to trace back to the fact that Sketchup is not a solid modeler, it's a SURFACE modeler, that defines a solid by its boundary surfaces, It will therefore draw surfaces that appear to enclose a volume, but really don't. Since the STL files used by most of the "3-D printers" are extracted from solids, if the Sketchup surfaces don't actually enclose the volume, then the solid isn't there, and won't be converted. This isn't a slight of Rob's CAD abilities, the problems most likely derive from rounding errors in Sketchup's calculations as it attempts to trim the various surfaces to each other. For the web animation purposes Sketchup seems to be aimed at, these errors are insignificant; not so for our purpose. I suspect that a step up to industrial grade software would solve the problem, but not cheaply.

Here is a link to a web discussion that has several links to software plug-ins that help identify problem areas in a Sketchup model:

http://sketchucation.com/forums/viewtopic.php?f=79&p=276399

Of course, finding the problem is one thing, fixing it is a whole 'nother issue.

Dennis




------------------------------------

Yahoo! Groups Links

I can see this discussion went on while I've been at work, so I'm coming back to it late. Anyhow . . .

The purpose of my efforts with 3d printing have been mixed. Some of the parts are one-offs and I'll use the printed version. But most of them are freight cars, and my intent is to get good masters for casting etc. The ADC product has been very satisfying in that respect, and does produce usable models.

The problems I've encountered with the CPR automobile boxcar are unique and reflect my learning curve. Having since completed a number of other drawings without problems, I know the problem is my own. I think somewhere along the line I started out with a careless minute error; without going into a lot of detail, Sketchup has the unhappy tendency of making such errors very hard to detect if you are not on the lookout for them while drawing.

For example, imagine a polygon of 24 sides - what Sketchup would call a circle. Imaging other shapes in the mode you are drawing result in lines that connect at tangent to the circle. Very often this will occur without any trickiness, and the lines will go where you draw them. But if a junction/end point between lines occurs so close to another junction/end point that it is within Sketchup's minimum, the machine will round them to a common point when in fact they should be two discrete very close points. If you know this problem, you can draw around it and avoid it. But even then one can occasionally fail to notice when it happens. So one starts to be more careful about these problems. And that will mostly allow you to avoid them. Dennis Storzek got me onto the problem of rounding errors - which is essentially what I am describing. Ever since I received his advice, I've managed to draw without too much trouble. But old drawings with lurking problems are very hard to fix.

Starting afresh and just re-drawing the car sides from scratch will result in good sides. I just have to want to do it - and I got to the point where I didn't want to for a while (although this discussion is bringing the desire back). For the time being I'm having a lot of fun doing a steam loco frame and cylinders . . . .

Rob Kirkham

--------------------------------------------------
From: "Richard Brennan" <brennan8@earthlink.net>
Sent: Friday, February 08, 2013 7:42 AM
To: <STMFC@yahoogroups.com>
Subject: Re: [STMFC] 3D printing challenges etc.

At 09:57 PM 2/7/2013, Rob Kirkham wrote:
<snip>

That too is too subtle with 3d printing.

So I've drawn and re-drawn it - and each time come to a leaky dead end.
When I get the interest back, I'm going to start from scratch and do it again.

I suspect the issue is NOT your drawing...
but the specific 3D print process/technology you are using.

Question - Were you expecting finished models to be:
1st generation: 3D print each car + paint + lettering?
2nd generation: 3D print master car car + resin-cast copies + paint +
lettering?

If the latter... then the need for 3D print quality trumps the desire
for a low cost print,
and you can find a print service that will do the resolution you
need. They do exist!

Just a thought...

--------------------
Richard Brennan - San Leandro CA
--------------------



------------------------------------

Yahoo! Groups Links

"I'm guessing you meant to say "Arial," the Microsoft look-alike of Helvetica, which is indeed more modern looking."

Thanks Tony.  That makes me feel better if I ever buy a Signature Press Book.  I will know that the proof-reading was top notch.  You also have one of the handful of blogs worth reading.

I had it right the first time, but Yahoo Mail did not recognize "Arial" as a word, at least when uncapitalized.  I figured that they knew best, but I bet wrong this time.

Thanks,
 
Matthew J. Moellendorf
Sturgeon Bay, WI
rboxfan@yahoo.com


[Non-text portions of this message have been removed]

It has always been his intention to make it available for free one way or another. It was through Al Westerfield that I became acquainted with this gentleman. The gentleman's late wife spotted an M&StL box car that had been turned into a billboard. The gentleman contacted Mr. Westerfield who in turn referred him to me as I now recall events.

There are a couple of good stories about the box car mentioned above that should be told sometime.

Gene Green

http://www.ebay.com/itm/111007867594
http://www.ebay.com/itm/121060850109
http://www.ebay.com/itm/111007867635
http://www.ebay.com/itm/111007866997
http://www.ebay.com/itm/111007867546

Tim O'Connor

Bill,

Excessive throw, while ugly, does not affect tracking. The open point isn't involved in guiding wheels. In fact, throw and heel spread should be large enough so the wheel back doesn't contact the back side of the open point.

A wheel dropping between the stockrail and open point is an indicator of wide gauge. Check the gauge through the point section. Sure, narrower treads are less forgiving of wide gauge, but that's not the root cause.

Frog flangeways of course are another matterand the relationship between wheelset standards and track standards is critical.

Jack Mullen

I appreciate the conversations about 3D printing but some might consider them slightly off topic and not specifically Steam Freight car material.

So I have created a moderated group for discussion of 3D printing as it relates to Model Railroading. (I'm personally interested in the time period of steam)
Members can get way down in the weeds on tech stuff here.

So if this topic interests you here is the link:

http://groups.yahoo.com/group/3DSTFC/join


Sorry Mike- I know a bit off topic...


Gordon Andrews

Matthew J. Moellendorf wrote:

Thanks Everbody (especially Tom). Since this caboose will have the older roman lettering, not the later aerial-style . . .

I'm guessing you meant to say "Arial," the Microsoft look-alike of Helvetica, which is indeed more modern looking.

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@signaturepress.com
Publishers of books on railroad history

Thanks Everbody (especially Tom).  Since this caboose will have the older roman lettering, not the later aerial-style, it looks like the roof will be black with a little galvanized metal showing through.  My dad officially models 1971, so the roof would be a little beat up my then if the roof was painted the same time as the rest of the car (before the second lettering scheme debuted when the U25C's arrived).  I can not quite tell, does the Athearn car have a wood or steel roofwalk, and would it be black or brown?

As for the "do whatever you want" plan, I would not be asking on STMFC if that was my plan.  I figure that things on the prototype are often done a certain way for a reason, so a private roadname model will look more plausible if it is built with consideration for prototype practices and changes over time.  Anything less would be comparable to drawing up my own design for a automobile with green taillights.  The vast majority of cars have had red taillights for at least the last few decades, and laws require red.  If I am trying to pass off my design as a real car that actually existed, it will be immediately obvious to even the casual observer that the lights are the wrong color.

And I apologize for clogging up STMFC with my occasional questions when this is really intended for prototype modeling, but you guy continue to always help me out when I need data on something like this.


Thanks So Much,

 
Matthew J. Moellendorf
Sturgeon Bay, WI
rboxfan@yahoo.com

I hope this will be commonly available. If he’s willing to make it available to all FOR FREE, he is to be truly admired.


SGL



From: STMFC@yahoogroups.com [mailto:STMFC@yahoogroups.com] On Behalf Of Al and Patricia Westerfield
Sent: Friday, February 08, 2013 6:42 PM
To: STMFC@yahoogroups.com
Subject: Re: [STMFC] Box Car Database





I assisted this gentleman for many years, supplying all my history sheets. His work is truly amazing. – Al Westerfield

From: Gene
Sent: Friday, February 08, 2013 12:34 PM
To: STMFC@yahoogroups.com <mailto:STMFC%40yahoogroups.com>
Subject: [STMFC] Box Car Database

Hi all,

I have alluded to this in previous posts.

A friend of mine has been working on a database of all box cars built or rebuilt between about 1910 and 1940 as well as any box cars that interested him from before 1910 or after 1940. For the most part the single criteria for inclusion was a steel underframe, either as originally built or added later. This is a car-by-car database and includes renumberings, sales to other railroads, builder and date built, retirement and date of retirement, type of roof, sides, ends, doors, hand brakes, trucks, etc. The database is quite useful.

This fellow has, in the past, asked me not to reveal his name nor forward him queries although I have had access to the database for my own personal use. (Yes, I felt guilty having access to this database and not sharing.) This individual has the scientific background and access to a great deal of information - way more than even the best informed of us - so that his product is of high quality and accuracy.

Today I received an email from this gentleman. I slightly FBI-style redacted version appears below.

Hi Gene -
"Thanks for thinking of me here. . . . . Nothing I can add to the conversation, though I do have service histories for these cars and could add that a mighty handsome #88958 restored to its original PM livery is in the B&O Museum in Baltimore though I'm not sure this info would be useful to the conversation.

"In this line of thinking, I have been coming round to the idea of posting the box car database for download. It would be a sanitized version without my working tables - just those parts that are more or less "finished." Still it would be large, but these days an easy download. I could re-post updated versions every 6 months or so perhaps. Do you have any thoughts of what might be the best venue to do this? Perhaps there is more than one place?"

I would like to pass along any ideas or advice anyone on this forum might care to post either on this forum (if the sheriff approves) or directly to me off list if that seems the better way to go.

At the present time the database is in some sort of ultra-sophisticated software that I don't understand. The software alone, to say nothing of the database itself, so exceeds the capability of any computer I have that I only tried once to download it. How it might be altered to make it available to the plebeian masses is beyond me. I have every confidence this person can do what needs to be done to make it available.

And no, he won't do refrigerator cars even though I am sure that every Santa Fe refrigerator car that ever existed still exists on some farm or ranch out west here. We could give him a running start.

Gene Green

[Non-text portions of this message have been removed]

--- In STMFC@yahoogroups.com, "pullmanboss" wrote:

Dennis asked:

Cool, Tom. Care to share some "fer instance" pricing, to compare them to Shapeways?

The part from Shapeways was $53.60 plus shipping. From ADC it was $120 including shipping. Probably not justifiable if you were making a part that size to use as-is, but cheap for a good pattern. (I love doing the 3D CAD work and, as with model building, place no value on the time spent.)

Tom Madden

Thanks Tom. Just a reality check on those who say that new technologies will make everything else obsolete.

There is certainly something usable here, but not the revolution that will make everything that came before obsolete. As the "masses" (those who haven't a clue as to what they are talking about) flock to the "better" service bureaus, look for the fees to increase, not decrease, due to the amount of hand holding time required.

Dennus