PLA 3D Printed Bushings. 1 Year Later... How are They Holding Up? Rostock Delta 

Thanks!! ~Russ

haha yes! mabey I should replace the display with nixy tubes? haha. next for this rig is to replace the eleteonics with my duet electronics. and then we should really be rocking! even at this age this thing just keeps going. it's a work horse and it's the rig I can test new ideas on. ;) thanks for the comment. 1.21 jigawatts!!!! ~Russ

:) ~Russ

лол пиздец

cool!!! thanks for the tip! ~Russ

yep, that always something to fight. what electronics are you using? most firmware's not have bed probing and correction. if you don't have a bed probe, install one! its a bit tricky to get all set up but once you do it *should help... ~Russ

rwg42985 Cheers Russ, I'm using a sanguino 1.3a (I also have the mega with the 1.4 shield for a separate project) it's all good, just the 'bowl' effect that I need to sort out before I run filament, I have the probe on my to do list, it will definitely be the first upgrade 👍

rwg42985 Oh, I'm using Marlin btw 🙂

ok greate. I ask because I go in to that here. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-nN1XsFWq1HA.html about 1/2 way through. you may as well watch it all tho. ~Russ

yes, but oil must always be applied, dry lubricant should be a one time application. i'm sure its best to apply more over time but alot less frequently than oil. good idea tho to keep the dust out !! thanks! ~Russ

2:39 explains a major reason :) hehe yes the arms do add to that small bit of slop, that's why its so important to keep it running with no slop. Thanks! :) ~Russ

you will laugh... i have some Igus bushings and rods here :) but after some doing and thinking i decided to go with the home made path... but yes, i could. that filament seems extremely pricey. Thanks! ~Russ

Hahaha bingo, you beat me to it. We used them to castrate male calves.

yes it is 100%, that's why the extra rubber supports relieve a lot of stress on the system. unfortunately unless i replace everything on the rails it is what it is... now you know why i went with the extruded AL on the OSD :) thanks! ~Russ

Perhaps you could retrofit this machine with thicker rods to cut down on that play? If it is worth it to you and you aren't just planning to use the OSD for everything in the future. You can get rod pretty cheap from china these days...

unfortunately, theses rods are quite expensive. They are 3 feet long and i will not trust that they will be straight when i get them in to post. that has been my experience so far, and i will not go the cheep rough on the #1 most important part of the system. 12mm rods would be really great tho. i think it would make everything Much better. ~Russ

Yeah, crappy rods can ruin your day pretty quickly. 3ft, sheesh. Hard to realize how tall the machine actually is just from watching videos :)

:) yeah quite long. x6 adds quick even at 10$ each or something... thats 60$ and I'm sure you wont find 3 feet 12mm precision rods for less than 15-20$ each. thanks!!! ~Russ

I found that nylon is a lot more sticky. with enigh lube it might work. but pla seemed to be better. I did not try anything else. in sure there is a better plastic as well. ~Russ

sounds like its comparison to graphite? I see they are all listed under wiki. i was going to try graphite, but its so messy. how about the other ones? do you know if there as messy as graphite? I see some come in a spray / liquid then try. that's ideal to applying dry lube i think. probably better than silicone. i guess ill be trying 3 more new options :) thanks for the tip! ~Russ

wow they even make Dry PTFE spray lube! that would work as well! ~Russ

Russ, the hexagonal boron nitride is probably the best as it's a white very fine powder that bonds with the metal or plastic and greatly reduces friction. I use it to coat projectiles in a match rifle. It does such a good job of reducing friction that it will lower the pressure in the chamber significantly enough that I need to load my rounds just a little hotter to maintain velocity. The best place I've found to get it is from David Tubb on the internet. The Dri-Slide is a dry molybdenum in a volatile base that evaporates rapidly leaving a dry non sticky lube film. The problem with it is that like graphite it leaves a very dark gray film that will rub off and discolor what it comes in contact with. All of them are very good dry film lubricants. Since I started purchasing the boron nitride I have probably coated at least 10,000 projectiles it really has helped my barrel life. Tony

thanks Tony, i think i'm gonna get some hexagonal boron nitride. after doing some reading and research it seems the best for what i want. applying it might be hard but worth it. do you know of any that is in a spray form? i see a company mixes it with acetone for application. not a bad idea... any hoo, thanks for the tip im gonna try it. Thanks ~Russ

Russ, there are several online sources for the aerosol HBN. Here is one source and a PDF describing the product. www.lowerfriction.com/pdf/22.pdf. Here is a site with info on using HBN. www.boron-powder.com/?gclid=CPHM8feqiNICFQMHaQodGO8A0w David Tubb products. www.davidtubb.com/tubb-accuracy-reloading/bn-boron-coating Tony

strangly enugh. I have some of those and. there suppose to be in a press fit steal housing. if there not, there not fit properly. And there for no good for this. they are slightly over sized. becuse the press fit compressed them. thanks for the comment. ~Russ

rwg42985 I printed some from Igus filament and worked them in. they started out right but after a little work the fit good and work well.

Igus also sells their bushings in the steel (or rigid plastic) casings already, those are supposed to be direct replacements for the LMxUU bearings. Quick search turned up the RJZM-01-08 (Man. Part No.) that is supposed to go on an 8mm shaft for about 9 GBP. Also, it seems that you can buy replacement bearing liners for those.

yes. this is correct. beleave it or not. the orgnial berrings / bushings were 1/2 the size of thses! the next ones I'm making are integrated with the part that hold the bushings. and there is 2 smaller bushings spaced 3x apart. so even better. however I need to make sure the arms don't go to far down as they will hit the bottom!! so limited on length by the travel. ;) thanks for the comment! ~Russ

rwg42985 I know, they seem very simular til the ones on my delta mini pro, so if specs are the same you could go up to half radius I think 🤔 😀

I moved the hall efect sensors. to the top of the bottom. so that's where my liminatation is. I'm home and it's at work and I for got to mesure it. lol. but I already for the design ready for testing. ~Russ

rwg42985 looking forward for the new parts, love the work

me too! lol ~Russ

it takes the stress off the rails / plastic parts and allows the motion to be counter acted. so when the endefector makes a sudden motion the printer in its entirety moves the other way. This helps with the stress that all the parts on this printer has. ~Russ

When the machine stops the moving print head, it wants to continue moving, so it presses against the arms, which press against the bushings, which press against the rods, which press against the chassis, which presses against the table, which presses against the floor, which is so solid it doesn't matter. So one of these things has to take the kinetic energy that's still in the print head and convert it to heat energy by bending/compressing. However, most of those things we don't want to bend. So we introduce a very bendy element along that way to do so instead---but not so bendy that the backlash bounces the machine around so much that its contents rattle around like beans in a bag.

thanks,that looks good too. I recently stated using this: www.amazon.com/Dow-Corning-Vacuum-Lubricant-5-3oz/dp/B001UHMNW0/ I have deigned bushings that use nylon, ( will post them soon) so this keeps the silicone "wet" as the dry silicone i show in this video is not enough. But the high vacuum Lubricant you can apply tinny amounts and it keeps it "wet" but it dose not collect much dust / dirt. ~Russ

I use Molykote 33 light for my paintball guns. stays wet and doesn't stick

yeah, i looked in to that cerflon, i got some "dry" lubricant that has that in it. question, dose that Liquid wrench leave a coating? aka will it pick up dirt? this is the one main reason why the silicone was in portent to me. It dose not collect dirt. thanks for the posts! ~Russ

Well, there are quite a few variants of lubricant that contain Cerflon. I only guessed that the white lithium type would be best for you based on my own experiences. They use white lithium grease a lot in other applications where dirt and contamination is an issue. In fact it's what you'll usually find on slide bearing type applications from CD/DVD/BluRAY drives, to automotive hinges etc. Really though the important factor is that whatever carrier your use (ie lithium grease, or silicone) it's really only there to deliver the Cerflon. Initial usage runs in the Cerflon into the wear surfaces where it does it's job for a long time afterwards. I would think that PLA might do a good job at picking up the Cerflon and carrying it from then on. The steel rails definitely will pick it up, eventually. If it were me, I would apply the white lithium Cerflon then make a gcode script to just run the extruder up and down from limit switch to limit switch and let it run for a while. Then once the grease has been fully distributed, wipe the excess off the rails and use the machine normally. Maybe repeat this process occasionally as part of regular maintenance. The perfect scenario would be brass slide bearings on steel rails. Soak the brass bearings in Cerflon overnight, then assemble and run the break in script to move the bearings on the rails for a while. I only buy fans with brass bushings for all my cooling fans instead of ball bearing fans. I then clean off any factory lube with WD-40, dry with absorbent, lint free cloth, and then apply a generous amount of Cerflon and let soak. Then I run the fan for a few minutes, unhook power, dry everything off, re-assemble and go. I have fans that have run non-stop for years after being treated this way. YMMV of course.

yeah lots of stuff there. most of those are oils of types tho. but some are "dry" ~Russ

"Russ, you are doing it wrong! you are supposed to adjust them so the slide freely with no play" Theses were tight when i installed them. its been 1 YEAR! Things ware out, even bearings!!! I may try a light oil on the next ones. but i found that the silicone coats everything extremely well. just like graphite... any how, only testing and time will tell... ~Russ

***** maybe its because of your rods. I'm using mine on polished chrome rods from some inkjet printers. The hardened steel rods i had for the lm8uu where bery porous even after a few minutes of 1500 grit sand paper. It was shiny and all but you could see tiny holes in the material, and the bushings certainly felt more grabby on the steel rather than on the chromed one. With the oil and running on the chormed rods, they felt like a hot knife on butter. It just slided like if it where floating on water. You could feel the viscosity of the oil but it certainly had zero static friction. Plus you could even see how the oil sipped under the bushing pads. Maybe it's design problem. I read a bit about bearings and lubricants before designing mine. I certainly didnt do the math, but i made mine so that they have a large contact area pad to "surf" on the oil layer. do you have a link to the bushings you are using?

yeah. if you have polished chrome rods then those would work really well. but over time things wear out. even with keep in good maintance. I have 4 years of life on three rods running allmoat every day. lol all the files can be found here. open-source-energy.org/rwg42985/russ/Projects/3D%20printer/2016%20RWG%20rostok%20delta%20updrade%20parts/ those are all the parts for the 2016 upgrade I did when I I stalled thses bushings. ~Russ

mainly because you can see it with the naked eye. I have a few dial indicators i could have used. but did not even think about it. i guess because i was not getting that scientific with it lol . thanks for the comment. ~Russ