One reason I hate to use 3D printed parts in my 3D printer I checked on Son of MegaMax at the makerspace today after someone reported odd behavior. It took about 5 seconds to spot the problem: broken%20ball%20nut%20coupler.jpg mod_embed_images_loadimage('0685405961f4dc0e177253189dba88a9', '/forum/thumbcache/f8e/b32/ebd/e8e/857/54d/107/04b/3b5/9c1/9d_800x400.png', 'http://mark.rehorst.com/misc/Fail/broken%20ball%20nut%20coupler.jpg', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Fmark.rehorst.com%2Fmisc%2FFail%2Fbroken%2520ball%2520nut%2520coupler.jpg', '', 683136, 800, 400, 'Loading image ...', false); Yeah, I know, the problem isn't the parts, it's my poor design... That part will be replaced with an aluminum one within a week. Never again! https://reprap.org/forum/read.php?1,683136,683136#msg-683136 Tue, 12 May 2026 23:34:58 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?1,683136,684064#msg-684064 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,684064#msg-684064
But if you want that plastic brace strong run the screws through to washers and nuts and use the compression of the plastic as its strength, rather than tensioning the bond between the printed layers which is creating as many 'fixtures' (attachment points that can fail) in the object as there are layers. Make the plastic part not the tension strength but instead the geometric guide for tensioning rods, m3 screws with washers and nuts. Sort of like earthquake retrofit in old buildings, reinforce through compression. It will then be able to break other things before it does, if that is your desire.]]> Milton General Mon, 04 Jul 2016 14:29:01 -0400 https://reprap.org/forum/read.php?1,683136,683713#msg-683713 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683713#msg-683713
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DjDemonD
Well sounds good to me, I try to print functional parts with 0.5 nozzles at 0.4 layer height. They are usually pretty strong, and print much faster. Been thinking about drilling out a nozzle to 1mm or similar and seeing what kind of parts I can produce.

I've been doing a lot of research into this lately. It seems one big limiting factor is how fast the hot end can melt the filament and that is largely dictated by the time the filament spends in the hot end. A longer melt zone helps. One needs to determine the melt rate for the hot end in mm^3/sec then divide that by the nozzle area to determine what speed you can use. The bigger the nozzle, the slower speed you have to use so the time to print an object may not be any quicker than using a smaller nozzle and faster speed. However, there may be strength advantages due to better layer adhesion. I'm also told that T Glass can look better when printed at bigger, fatter layers but I have no personal experience of this.]]> deckingman General Sun, 03 Jul 2016 06:29:27 -0400 https://reprap.org/forum/read.php?1,683136,683712#msg-683712 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683712#msg-683712
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deckingman
When E3d were testing their volcano nozzles, they found that parts printed with wider and thicker layers were very much stronger than "normal" layer heights. [e3d-online.com]. I haven't tried it myself....
I did try it after buying a volcano and using the 0.8mm nozzle and they (E3D) were right. The printed parts were stronger. Specially the 100% infill parts are very strong.]]> Frans@France General Sun, 03 Jul 2016 06:27:56 -0400 https://reprap.org/forum/read.php?1,683136,683692#msg-683692 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683692#msg-683692 DjDemonD General Sun, 03 Jul 2016 04:22:55 -0400 https://reprap.org/forum/read.php?1,683136,683689#msg-683689 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683689#msg-683689 e3d-online.com]. I haven't tried it myself but found it interesting and thought provoking. Don't know what layer height you used on the failed part but as it is a functional part and doesn't need to look pretty, then maybe thicker/taller layers might make it stronger? Just trying to be helpful but I expect I'll get roasted as usual for daring to make a suggestion.]]> deckingman General Sun, 03 Jul 2016 03:51:04 -0400 https://reprap.org/forum/read.php?1,683136,683663#msg-683663 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683663#msg-683663
I was thinking about the secondary kill switch thing. It seems like a good idea, but definitely a low frequency type problem, so worth the trouble? It took a couple hours to fabricate a new coupler after a few false starts, so a set of kill switches, at least on the Y axis with the beefy motor (425 oz-in hold torque) and drive screw, are probably in order.

I agree, the screws could/should (?) have been longer, and nuts and lockwashers could/should (?) have been added, or maybe threaded inserts... Plastic may be best for this part to prevent major damage in the event of failure. I'll have another go at the design and print a couple copies. If I add washers and nuts with the plastic, it may get strong enough to result in major damage in event of a failure. Maybe I got lucky that the design was just poor enough to fail in an unspectacular way.]]> the_digital_dentist General Sat, 02 Jul 2016 23:30:53 -0400 https://reprap.org/forum/read.php?1,683136,683619#msg-683619 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683619#msg-683619 IMBoring25 General Sat, 02 Jul 2016 15:59:10 -0400 https://reprap.org/forum/read.php?1,683136,683614#msg-683614 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683614#msg-683614
Or perhaps as was being said in another thread about head crashes, since most don't cause that much damage maybe its a low frequency low severity risk. Maybe more risky if the machine is loaned out/resides in a makerspace.]]> DjDemonD General Sat, 02 Jul 2016 14:44:09 -0400 https://reprap.org/forum/read.php?1,683136,683604#msg-683604 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683604#msg-683604 JamesK General Sat, 02 Jul 2016 14:11:37 -0400 https://reprap.org/forum/read.php?1,683136,683584#msg-683584 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683584#msg-683584
There is a hard stop at the front, just beyond Y=0, but if it had hit there it would broken the coupler in the opposite direction and the damage would have looked quite different.

There used to be a hard stop at the back of the machine, but apparently I neglected to reinstall it after doing some work on the Y axis many months ago. That's going back in.

I'll think about a redesign of the printed part- busted plastic is probably better than twisted metal.]]> the_digital_dentist General Sat, 02 Jul 2016 12:25:35 -0400 https://reprap.org/forum/read.php?1,683136,683562#msg-683562 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683562#msg-683562 LoboCNC General Sat, 02 Jul 2016 11:27:25 -0400 https://reprap.org/forum/read.php?1,683136,683405#msg-683405 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683405#msg-683405

]]> the_digital_dentist General Fri, 01 Jul 2016 19:28:45 -0400 https://reprap.org/forum/read.php?1,683136,683211#msg-683211 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683211#msg-683211 DjDemonD General Fri, 01 Jul 2016 05:36:36 -0400 https://reprap.org/forum/read.php?1,683136,683198#msg-683198 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683198#msg-683198
The only remaining 3D printed part (other than some LED mounting brackets and and things of that nature) is the X axis belt tensioner. I'm going to step up the effort to replace that, now, before it, too, fails.]]> the_digital_dentist General Fri, 01 Jul 2016 04:54:47 -0400 https://reprap.org/forum/read.php?1,683136,683194#msg-683194 Re: One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683194#msg-683194 Origamib General Fri, 01 Jul 2016 04:50:08 -0400 https://reprap.org/forum/read.php?1,683136,683136#msg-683136 One reason I hate to use 3D printed parts in my 3D printer https://reprap.org/forum/read.php?1,683136,683136#msg-683136


Yeah, I know, the problem isn't the parts, it's my poor design...

That part will be replaced with an aluminum one within a week. Never again!
]]> the_digital_dentist General Thu, 30 Jun 2016 23:31:57 -0400