Those are simply not good prints. This is a result of several things, including the fact that they are just not good prints.
Since printers is an ambigous term, I will refer to Persons and Machines…
If the person is not good with ABS settings and such, this will be the result. The ABS is shrinking differently when the layer with the holes is being printed, than not, and that is why you are getting the warping in that area. A good person will not produce prints that look like that.
The issue is not that most machines print layers differently when there are holes, the issue is the person setting up the print is not doing a good job, or the machine they are using is not good at printing. But a person who knows how to handle ABS and has a good machine will give you a better print.
Next, consider PLA. Yes, theoretically, ABS holds up better than PLA in heat (a slight difference), and works better when the item has a hinge, because ABS can take a few more bends than PLA, and ABS cannot be shock broken as easy.
But the differences are so minimal, that I would advise you to directly go to PLA. ABS is a material designed for extrusion molding, so it is specifically designed to shrink from the mold. As such, it is more prone to warping and shrinkage while being printed. PLA crystalizes as it cools, and as such, is more exact to the original digital model. For an electronics case, PLA is often a more perfect material, and unless this is an item that will be in an automobile, or direct sunlight, or has a hinge, or is going onto a quadcopter, I would recommend PLA for a perfect, durable, long term item that prints without shrinkage or warpage.
That being said, I would still suggest that the ABS print you are showing was done poorly, even an ABS print should be better than that, by alot. It is simply a poor print. (even so, I would still recommend PLA)
Finally, I can’t be sure how large the print is by the pictures, but it looks extremely small. As such, it seems to me if you need 50 in a year, 3d printing is a good option. I can print small parts inexpensively, as I have some printers with several print heads that can print at once. Or, if you want to print in small batches as you go, such as when orders come in, than 3d printing is a great solution. Also, if you see yourself making changes as you go, 3d printing is a great solution. But just as an FYI, if you know you will be using 500, then you want to go with extrusion molding.
If you want to discuss this further, or if you want to share your model with me so I can advise you further, contact me https://www.3dhubs.com/cleveland/hubs/perry. You can upload the model for a quote or just start an enquiry.
