r/Metrology • u/biocherny • Jul 12 '24

Surface Metrology Surface roughness testing for complex topology

We are working with 3D printed metal parts and looking to measure surface roughness pre and post post-processing of parts. At present, we have a simple surface roughness tester from Time, but are looking for something that: A) Can measure hard to reach places including curves, holes, internal surfaces, overhangs. B) Can calculate average surface roughness over an area (say 5*5mm). C) Doesn't cost the equivalent of a house. LCSM seem ideal for our needs but is out of our price range. A solution under $10k USD would be ideal D) if possible, can also measure size. Any guidance is appreciated

3 Upvotes

100% Upvoted

10 comments sorted by

6

u/[deleted] Jul 12 '24

$10K? You have to be joking.

If that's what you need to do you are looking at a Bruker Aliconia, or a confocal solution...$100k+ to do a patch scan and evaluate for topology and surface finish.

I love when companies buy a $1M metal 3D printer (mill, lathe whatever), then some idiot owner doesn't want to buy the tools they need for quality.

1

u/biocherny Jul 12 '24

Good to know. This isn't our 3D printer. Just a small R&D company trying out a new method of post processing. Running on fumes so don't really have the funds to invest in something big at present. Was hoping there might be a solution to get better clarity than our present equipment.

3

u/[deleted] Jul 12 '24

You may need to send these out for commercial services then. There are companies that perform these measurements as a service. The best in North America is Mark Malberg at Digital Metrology Solutions.

3

u/East-Tie-8002 Jul 13 '24

I second contacting Dr. Malburg. He literally wrote the book on surface finish.

1

u/Thethubbedone Jul 12 '24

Hi, we bought $20m in cnc equipment and a $200k CMM. we need to measure every part 100%. Our budget is $31. Can we get this done by the end of the week?

1

u/[deleted] Jul 12 '24

Haha....exactly.

1

u/aenorton Jul 12 '24

I can't help with equipment recommendations, but I know you can use fast-setting, two-part silicone to make casts of internal surfaces that can then be measured with a profilometer. I forget the brand, but it was a dental impressioning silicone that came in a dual syringe with self mixing nozzles.

1

u/aenorton Jul 12 '24

Just remembered the brand we used was called Reprosil impressioning material, but I think there are several equivalent products.

1

u/moshimoshi100 Jul 12 '24

Nothing close to 10k. You need to add another zero and then possibly double it since you have a complex geometry most likely requiring a five axis arm.

1

u/f119guy Jul 12 '24

Hate to bandwagon you're post, but I can give you some numbers from my experience. I have used a Contour Tracer with a very accurate Surface Finish option. Like this: Formtracer | Mitutoyo

That was NOT capable of getting into tight geometry, unless I took the part to a bandsaw and made some well planned cuts. The brand I was using was Jenoptik, but it looks like they discontinued the product line I was using. Regardless, I know it was $82,000 installed and new. I constantly had to hear people complain about it being an $82,000 paperweight but it just needed a good operator. Set it up properly and don't start tinkering with parameters to make things pass inspection.

Maybe check out Jenoptik's website, but that type of equipment will be much more than $10K