3D Printing Tips and Techniques

[ChalkLine]

Another question!

What's the least complicated method of measuring the dimensions of an object in an .stl file?

I've got myself an awesome Soviet civilian car that's made to no scale in particular but looks about as big as a truck in 1/35.

By the way . . .
. . . I may have developed some sort of .stl collection addition as it seems in the time I've been posting here I've collected 368 files, most of which are .zips containing multiple objects.
As I of course hold myself entirely innocent of this you'll be hearing from my solicitors in the morning about covering the costs of my rehabilitation.

[Frank3k]

If your computer is running Windows 10 or 11, you can use 3D Builder (which is free and comes with the OS) to measure and scale (and also repair) .STL files.  You can also get Netfabb Basic, which can also measure STL files and does an excellent job of repairing them.

[Buzzbomb]

I have seen first hand what hollow models without sufficient drain/gas escape holes can do.
A Buddy of mine is a Dinosaur freak, which has a large number of 3D printable subjects. He has shown me a couple of "exploded" Dino bodies, where the expanding gases inside the hollow structure caused the body to crack, sometime quite spectacularly

[ChalkLine]

I have seen first hand what hollow models without sufficient drain/gas escape holes can do.
A Buddy of mine is a Dinosaur freak, which has a large number of 3D printable subjects. He has shown me a couple of "exploded" Dino bodies, where the expanding gases inside the hollow structure caused the body to crack, sometime quite spectacularly

Has no one suspected xenomorphs?

[ChalkLine]

If your computer is running Windows 10 or 11, you can use 3D Builder (which is free and comes with the OS) to measure and scale (and also repair) .STL files.  You can also get Netfabb Basic, which can also measure STL files and does an excellent job of repairing them.

Sadly the Netfabb file is no longer available.

I'll use 3D builder, we'll see how it goes.
I've never done a rusted out car under rubble before so this should be fun

[Frank3k]

Sadly the Netfabb file is no longer available.

It is - just click on the releases link.

[robunos]

@Frank, not really on Topic, but I saw this and thought of you . . .   


https://cults3d.com/en/3d-model/art/garage-tools-furniture-welding-machine-compressor-jack-vise-wrench




cheers,
Robin.

[ChalkLine]

On what Frank said some time ago.

Just because someone on Cults3D says it can be printed and gives printer settings for it doesn't mean it's true. You might buy it and then find they say "it's an .obj file that I converted, I didn't say you could print it".

It's a good idea to check the comments section and see other purchasers feedback before buying expensive files.

[Frank3k]

I would avoid buying files from Cults3D. Free stuff from them is OK. There are a lot of excellent free files elsewhere, or other sellers.

OBJ files aren't useless, but you need to put in a lot of work to make them printable.

Story has an uncanny ability to find .STLs. Maybe he can chime on with his strategy.

[ChalkLine]

On what Frank said some time ago.

Just because someone on Cults3D says it can be printed and gives printer settings for it doesn't mean it's true. You might buy it and then find they say "it's an .obj file that I converted, I didn't say you could print it".

It's a good idea to check the comments section and see other purchasers feedback before buying expensive files.

[Update]
3D Cults gave me my money back but the seller is still selling the files . . .

[ChalkLine]

What's the thinnest I can make an object that will print?
I'm using an Elegoo Saturn 4
I'm doing a M2HB buffer mount and as I'm doing the ammo can bracket I'm not sure how thin I can go.

[robunos]

I can only say try it. Start wih your desired thickness, and increase it until you get a successful print.
Be prepared to drain the vat and clean the FEP several times . . .

cheers,
Robin.

[Frank3k]

What Robin said. With some experience and lots of trial and error with lift speeds, exposure and supports, you might be able to get 0.3mm - 0.5mm thick walls or thinner. The problem is going to be removing the object without having it break; I typically print walls no thinner than 0.75mm - 1mm thick.

The M41 turret I printed with 0.6mm walls (by mistake) was very fragile.

Also, what he said - clean your vat often and check your build plate for any small pieces of stuck resin. I use the tank clean function before every print job and drain the vat and check the FEP every 2-3 prints.

[ChalkLine]

Thanks for all the help on this guys, I'm a bit hesitant about wrecking the bloody thing :)

[ChalkLine]

Looking at something like the images below, this is a solid* object obviously ripped from some game or something. Here come the questions:

- Should it be cut into sections?
- Should things like the suspension be printed separately?
- Should I put bulkheads or supports inside to stop the body deforming?
- Will the grille/exhaust print properly or will it get supports stuck inside?

The reason I pester everyone with questions is I will probably only get one print per six months or so here so I want to get it right the first time.
 

*It's full of voids but I'm going to fix those and then hollow the model as well as make up some of the interior.

[Frank3k]

What really helps is to picture how a resin printer works.

- The build plate moves up from the resin and peels each cured layer from the FEP.
- The layers have to be supported during the print so support placement is important.
- The surfaces facing the build plate will have a lower quality than the ones facing the screen.


You could probably get away with printing it as a solid object if printed at a slow speed, but it may end up looking like Dagor that Ramba got with difficult to remove supports.

For this vehicle, It looks like it's 150 - 170mm long, so it will be best to print at an angle and support it well. I would separate the wheels and all the dangly bits and print those separately. The exhaust protection grids may be OK as is. I would the hull as a hollow object, mainly because of the weight; give it 2-3 mm thick walls and make sure that there are sizable vent holes to reduce or eliminate any suction forces on the FEP. The turret ring cover can be printed separately as well, and just add a big hole in the bottom and print plug for it on the same build plate.

[Buzzbomb]

The shape I see has a very straight section where a horizontal split might work along the hull. This would then option in the interior, although the amount of interior you could actually see would probably not make it work the design effort against straight on scratch builds

[taiidantomcat]

I got a PLA printer from Santa. I was hoping for a Resin printer so I could do detail parts for models.  I began to I realize however, that this thing can basically make entire models (within reason of course) and my mind was blown. 

for someone who is interested in things that would require full and total scratchbuilds from video games, this thing is a godsend. I might get a resin printer eventually but for now, I am having a ball.

I am still working on the slicing and other software, but I have set a personal benchmark of learning one new skill set per day, and an I am rapidly advancing. The other day I made first "from scratch" part, a very basic radial engine cowling (Cylinder with a ring on top, and a hole in the center)

the ability to scale things up, scale them down, scale to fit, or change shape and size in all 3 dimensions is an absolute game changer.

Hoping to post some more in progress pictures in other threads.