Are all 3d parts as porous as

sand ? I have a 3d made adjustable butt plate,it broke without too much force on it; I looked at the pieces and they are really porous....tried to superglue them together and they melted.....ummm....I liked that adjustable butt plate....I must ask myself this..can I remember NOT to rest my HW97 on its' butt? Will can I.....

What luck have you gents had with your 3d printed parts....
 
Like he said many different materials to feed the printer. Also many different temperatures and travel speeds. All of these affect the finished product greatly.

Some are good at it some well not so much.

What he said.

Hell, even various different metals can now be used in 3D printing. BUT, as even with different plastics, you HAVE to know what you are doing.

Plastics, heats, speeds, coarseness, etc., etc. JUST having a 3D printer, doesn't mean you should be doing some...things.



Mike
 
I found an adjustable butt on Thingaverse. Dew up a mounting plate for my Prophet Performance using FeeCad3D. Printed it in PETG at a fairly high infill percentage, ~40%. Works great especially on a short butt plate like the one on the Prophet. Has not broken.

Mounted.1644417531.jpg

 
When considering part strength, perimeter count is more impactful than infill percentage. Also incredibly important is the part orientation on the print bed -- you want the part's layer lines to be orthogonal to the greatest forces applied to the part when in use. These factors as well as others already mentioned (material selection, print temperatures, tempering, etc.) can help you make durable parts as a creator, and can help you know what to look for in 3D printed items as a consumer.

It would be informative for everyone if you could share a photo of the broken part.
 
There are 3d printers that print in steel, stainless steel, copper, titanium, brass, etc. For example, a titanium 3d print, straight out of the printer will have a strength similar to mild steel.

As mentioned, the quality of your 3d print will depend on exactly how it is printed, and the materials you use in the print. There are many parameters that can be adjusted, as mentioned, like layer thickness and "infill" i.e. hollowing-out of the part. 
 
Sounds like he was using ABS if the super glue melted it. While ABS is technically the strongest material a hobby 3D printer can use, it also has a nasty habit of reacting to chemicals like super glue and acetone. I prefer to use PETG for most of my "practical" prints on my airguns as it doesn't react to chemicals like ABS. 

The infill should be 20-30%. Anything more than 30% and you might as well print it as a solid piece. 

You'll want thick walls too. Assuming your printer used a 0.4mm nozzle, you'll want at least 1.5 mm wall thickness.

Even print orientation should be taken into account as layers can still split if the stress for instalation is too great.

I've designed and made 3D printed tools for industrial applications so I've a lot of experience in not only designing the part, but setting up the printer to create the best piece possible.
 
boscoebrea - "tried to superglue them together and they melted". Just like 3D printing gizmos all superglues are not the same. Back in my RC airplane days I made several planes using foam wings and skinning them over with 3/4 oz fiberglass cloth and superglue. Use the Bob Smith brand "GOLD" and it will not melt foam or plastic. Also no odor or fumes, but it costs more.