Hello there. I just got this scanner recently, and I went through tutorials using both “on-click” edits and manual edits. The included statue of Caesar scanned flawlessly (already 3D printed it, too.)
Now, I’m trying to scan a small worm gear (about 1x1.5”). It’s jet black and shiny, so I used some blue scanner spray on it, so it shows up ok. I scan it in 2 positions, but they never merge together either in fusion or mesh steps. It does lack features as it’s a perfectly round worm gear with a shaft hole in the center. So, I tried putting markers on it and scanning in that mode, but no luck. The spray is wearing off now. See photos (only allowed to post 1). Ideas?
Hi Mike, A worm gear is going to be very challenging, but not impossible, because the feature is a repeating pattern. I would suggest using the same process as scanning a sphere in the volumetric accuracy vid in this post MetroY videos and comparison with SermoonS1 , and if you are still having issues, the second thing i would do is attach something that is not symmetric e.g. a bolt through the axle with some sort of rigid flag on either end, etc Get a bit creative with the approach but just make it unsemetrical so that there is enough of difference in the views. Good luck, and let me know how you get on
Thanks for the ideas. Markers don’t help much (and hard to stick to sprayed item). I’ve also seen videos suggesting making 2 independent scans, processing them through the fusion steps, then merging them by using the merge option. Perhaps, that’s worth trying.
Yes, this is the correct way of merging. As for the markers, you would have noticed the markers are on the background that the object is resting on in the video I linked, not on the object being scanned. In this post, Power steering pump I show an object I have attached for scaling, but the same idea will work with the worm gear. I’m guessing it’s either really late where you are or you are on my side of the rock
It’s 9:21p here in California, not late, but it is past my 74 y.o. body’s bedtime. Thanks the ideas. If I do something that works, I’ll update this post.
Here’s the worm gear that I’m scanning. That small, threaded hole is 8-32 thread for set screws on both sides. Maybe I’ll screw something into it and add something flat for markers. The through hole is .250” Goodnight all.
yeah there is literally nothing unique about that part that would allow merging. if you had a 3d printer i would print some organic shaped part with a boss that fits the drive shaft hole and scan it completely like that. but to be honest i could CAD that up in under 25 minus and that is where this all falls apart 3d scanning is generally for parts that would be hard to model because of there unique shape. i mean the hardest part of this would be figuring out gear modul / pressure angle but you can buy Gage sets for that. I’m not trying to discourage you. i would like to see you do this and when you succeed know that you have done something that is not for the beginner
5:30 a.m. here. Only 6 hours sleep though…wish I could sleep like I did as a kid again. Anyway, I think you are spot on with your advice. You obviously know what you’re doing.
Yes, my goal is to use my Bambu P1S to print this gear in PA6-GF (recommended because it can stand up to friction heat - the original vintage gear was made in nylon). I can still buy that black gear (solid aluminum). It cost $100 usd. I have bought about 10 of them to repair machines over time. Some people use CNC to produce it, but there is a an outfit in Europe that makes it 3d printed (and it works), so I thought I would give it a try. There’s actually not a lot of demand for that part, but it interests me.
And yes, I thought about making it in CAD (I use FreeCad which does have a gear module available). There’s a couple of decent videos about how to do it, but I’m always stymied by the measurements required. If you could provide an affordable brand or link to gauges that might help me in that area, I’d appreciate it. Cheers.
Good morning! First, never accuse me of knowing what I’m doing . Yes, PA6-GF would have been what the original gear would have been made of, with the amount of GF being the only variable. As for CAD, IS the machine metric or imperial? Secondly, I have a stupid idea for your organic shape to assist in scanning, use a 3D printed statue of liberty and make the torch into a boss to mount the gear on, asymmetrically scale it so it’s fat and short (I just had a thought then, but I will stay out of it) put the two grub screws into the gear and clamp it onto the Boss so it cant move!
I’ve cut off Caesar’s head (my 3D print) in Bambu Studio, added a .250” press-fit pin on the bottom and stuck him on the gear. It scans in pretty good now, but the gear looks like sh*t. I’ll give it another try later on today or tomorrow, but I’m guessing that I’m gonna go the CAD route at some point. See attached.
The machine that uses the gear is built on U.S. inches for measurement and was made in U.S. circa 1976 (so the gear surely uses Imperial sizes). My FreeCad is set to metric, but I could change that or use conversions, I suppose.
That is a very small gear! One tip that may help is to align the scanner’s cameras with the roots of the teeth so they have the best chance of seeing into them. This means the scanner would be horizontal with a bit of tilt to it. Also have it facing directly at it and not looking down at an angle so it can “see” down into the roots.
Any print material with fibers will be abrasive in rubbing conditions like a gear and likely leave small debris as things wear. So plain nylon or better yet ppa without fibers would be ideal as it is very strong and quite rigid unlike the normal nylons without fibers. Siraya techs ppa without fibers is awesome stuff fyi.
Printing that type of gear needs supports and could be tricky also to end up with a smooth surface but it would be worth a try.
I actually got hold of an stl file that I guy has made using CAD and made available for free. His idea was to make it hollow like the original and press it on to the original aluminum hub. But, I think that’s bad idea, because the aluminum hub obviously heated up and cracked the original gears off the hub. I’ve replaced original gears that have shatter completely. See attached photos of a typical failed original gear (all 40-50 years old now).
Also, it appears the the original nylon gear was probably cast resin to grab the knurl on the hub. Anyway, see photo attached of this fellow pressing his hollow gear onto the original hub using a vice (he says that he used a “bit of glue”, too ).
Nope, I want a solid gear like the aluminum one, CNC, even FDM. Anyway, I downloaded his “hollow” gear file and made it solid in FreeCad and used PLA just for a test. I have turned off support for small overhangs. Yes, surface quality may kill my idea of making an FDM version (but I did install the one from Netherlands, and it worked well). It’s also is a bit small in diameter. See orange PLA test gear attached. Maybe, I should just move on to a more fruitful project, but even so, I’ve learned a lot.
You have me curious on what this gear is used in. It looks just like a multistart thread with 7 starts. If it was nylon then it was either injection molded around the hub or the hub was heated and pressed into it. Will you share the model file you made? I would like to try printing it just to see if I can from ppa.
. Yes, PA6-GF would have been what the original gear would have been made of, with the amount of GF being the only variable. As for CAD, IS the machine metric or imperial? Secondly, I have a stupid idea for your organic shape to assist in scanning, use a 3D printed statue of liberty and make the torch into a boss to mount the gear on, asymmetrically scale it so it’s fat and short (I just had a thought then, but I will stay out of it) put the two grub screws into the gear and clamp it onto the Boss so it cant move!
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