strange resizing...

I'm starting to really get frustrated with this place.

I drew my part 1 to 1 scale, so that I would know what size it was from beginning to end. The overall part ends up being 4-1.32in length.

I upload, and discover that it is now 3" in height.

What the heck happened ???

I've also drawn this thing several times with a 1.1mm tube attached, and every single time it comes back listed as "too small"

Why does this thing always resize what I send?

I'm going somewhere else, even if it costs more, if I don't get some acceptable answers here.

Can you share the file with us so we can take a look?

How do the dimensions work out in NetFabb?

I'm not sure how to "Share" the file, but I would be glad to if I knew how.

I also have no idea how it works out in "net fabb" since I don't know what that is.

from the looks of the image i am thinking that you are modeling in sketchup...

am i right?

how are you uploading the thing... if you are using stl then it is unit dumb... i would suggest using blender instead but that is because that is what i know. netfab is a program that you can download that will analyses your object and tell you all about it... including it's size.

if you want to you can attach the file with the "upload file" button at the bottom of the page... i never really liked doing that though because it exposes your model to the masses...

anyways... there you go.

chris

Netfabb can be obtained from here for free: http://www.netfabb.com/basic.php

It is a tool that allows you to review / fix / modify / measure a STL file. It is VERY good practice for you to use it to check your models before you upload them.. it improves your chances of success with uploading.


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To "share the file".. you've got 3 options:
1) upload your model to your shop and then mark it as downloadable, or
2) attach the file to your forum posting, or
3) if you would rather keep the file private, use the PM button to send a private message to someone here, and attach the STL to the PM

I bet you good money one of the dimensions in your model is 3 inches. SW will render your model differently than your program does. So your" up" in your program could be their width, thus discrepancies in dimensions. If you are using Sketchup, export as a dae. Whatever values you use in SU are really in inches, even when you are using cm, mm for measurements. Be sure to explode any components/groups , select all entities before uploading as a.dae.

When you upload to SW a stl file, of vital importance is to know the bounding box dimensions. Meshlab is another free program that can determine the dimensions. To find them, upload your model, click Show Layer dialogue on top panel, then click Filters/Quality,Measures and computations/Compute Geometric measures. You will see the dimensions. If you created a model in SU, the values might be different. I made cm 5 x 5 x 5 cube in SU. Imported it into Meshlab, dimensions were 1.96802 for each edge. THATS NOT cm 5 x 5 x 5 !! I used to think. you multiply that number by 2.54cm, it is 5cm. So just chuckle, when you upload the stl at SW,set unit to inch, its all fine. If on upload you set it as mm, you are screwed. Result is a cube 1.96802mm on each edge.

An stl does not contain scene data, just mesh data, that is why you have to set unit measurement. You want the dimensions of your files bounding box to be printed that size. Whether the dimensions matchup, is determining how you position your model in your program. Remember as long as the volume in your program matches SW's, you are set.

By the way Netfabb has the same capabilities, but shows the dimensions with a mm at their end, which is bad wrong. But it repairs stl to some extent, so I overlook it.

@lancer525 - sorry I forgot to link NetFabb, but I see others have linked to it.

Netfabb uses either mm or inches and can convert a model from one to the other, the option to change the units of measurement is under the 'Settings' menu.

Section 2 of https://www.shapeways.com/tutorials/errors goes a little way into explaining the measurement units for different filetypes.

Upshot is that whatever units you're using in your head for the build, make sure your software exports those same measurement units and you select the same measurement unit when you upload to Shapeways - oh, and when you do get your model uploaded to shapeways and the size is right, ignore the orientation of the preview render

Paul
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stop4stuff Modeller for hireShapeways ShopTwitterYouTube​

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Thanks for the replies, gents, but there's not going to be any other software packages that I have to learn, especially since I needed this item by the 14th. Probably won't get it in time, but we'll see.

I drew originally in sketchup, and used a plugin to export in STL, and then rechecked the file in Lamina. Everything came out okay in Lamina, which showed what wasn't connected, what needed adjustment, etc. The original was drawn in MM, in Sketchup, and converted to inches in Lamina. That conversion was dead-on balls accurate.

"Up" in one program might be "width" in another, but the dimensions are the dimensions regardless of the axis There is no good reason for any one program to resize what another does. None.

At any rate, I redrew it from scratch in Sketchup, in inches and millimeters (two different files, two different drawings) and then checked both in Lamina, where they came out identical in both respects. Uploaded the file that was in inches, and suddenly, it was 19" in length, with a price of over $110

So, I redrew it again from scratch in mm, in sketchup, (simplifying one or two of the details by finding an easier way to draw it from practice) and now it shows exactly what I drew in the exact scale I needed, after the upload here.

That tells me that it's Shapeways, and not me, since this is the only place that's resized anything.

I hope this time they don't find anything wrong with it, (especially the raised letter, because that's just a silly issue) because I don't want to have to do this all over again somewhere else.

The dimensions of your model are not necessarily the dimensions of the bounding box shown on the model page - afaik, Shapeways Mesh Medic will adjust the axis orientation to create the smallest possible bounding box.

As for the actual measurements being out, that is a common 'fault'. An STL file has no native units of measurement - frustrating as it seems, there is usually a simple solution to getting the correct dimensions every time - I should know, I started out uploading to Shapeways as DAE, the sizes were all messed up, but it turned out I was using different units of measurement than what I thought, and uploading in the wrong units too. Another thing that could mess things up is if you have a mouse with a scroll wheel - click the units on the upload page, scroll down with the wheel and the units change if the dropdown is still selected even if not visable on the page (this is a common trait with all websites.)

Paul
[hr]

stop4stuff Modeller for hireShapeways ShopTwitterYouTube​

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