The solution is not to use captive hex nuts. You can simply print M4 size threads inside a hole and screw the cap screw into the threaded hole. This works if you don't go through so many assembly/disassembly cycles. The best is to use these heat-set brass thread inserts. Then your screw goes into brass threads.
In all cases, blue (medium) Locktite works well. amazon.com/Threaded-Heat-Set-Inserts... <https://www.amazon.com/Threaded-Heat-Set-Inserts-connecting-injection/dp/B07BH5X252/ref=sr_1_18?dchild=1&keywords=m4+brass+insert+3d+print&qid=1598128018&s=industrial&sr=1-18> On Sat, Aug 22, 2020 at 12:39 PM Gene Heskett <ghesk...@shentel.net> wrote: > On Friday 21 August 2020 18:32:11 Gene Heskett wrote: > > Thread continued, sorta. > > Another problem I am noting, and I'm curious if its been noted by others, > and any possible fixes for it found, "cold flow". > > Several places in this assembly are held by m3 cap screws, and while the > nuts should be held, there's no lock washers, nor room for them. So you > tighten them 1/4 turn from broke. But just sitting on the table > overnight, you can remove the nuts with your fingers the next morning. > The plastic has relaxed due to cold flow, releasing the tension on the > nut that WAS holding it tight 10 hours ago. > > This gorilla stick glue can be used to keep the nut from vibrating plumb > off the end of the bolt and mucking up the works, but its still loose. > Is that the best we can do? > > Use with the new micro-swiss hotend and feed conversion is still young, > but since putting a narrow strip of teflon tape wrapped about 2 turns > into the nozzles threads, and carefully trimming it so no stray tape > could block the nozzle, I've had no repeats of that problem. And I'm > getting close to zeroed in on the feed rate, I only have it advanced to > 110% and the part being built is looking great. > > Thanks all for any suggestions about cold flow problems. > > > Yes, that thumping sound is what you think it is. ;-) > > Cheers, Gene Heskett > -- > "There are four boxes to be used in defense of liberty: > soap, ballot, jury, and ammo. Please use in that order." > -Ed Howdershelt (Author) > If we desire respect for the law, we must first make the law respectable. > - Louis D. Brandeis > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
