Greg, Rockstar stuff, TYVM
My friend is in AZ and temps above 110 in the summer are common all of which means didly since talk about temps and PLA do not make it so as you point out.
On the other hand the DD motor support now on my Ender 3 V2 was originally made from PLA (I said I was ignorant right?) and when printing stuff inside the enclosure, it melted like a popsicle in the sun. Surprisingly the print finished almost perfectly. See that pic for a laugh. The trolley wheels were even rubbing on the underside of the folded over support grinding away at the plastic. This did not affect the part at all as far as I can tell.
I have a dual screw/motor Z arm which I check for level using some digital gauges before every run. Well, before every first use at start up after a shut down. It stays bloody accurate when left on but a shutdown can cause it to loose its level.
So, and this is me asking, I should connect the plate that you clearly show is not part of the body to the body? In CAD, it is another part but I can make them as one. Being the old fool, I didn't even think for a moment they'd be seen as separate parts by the slicer where they meet up even if , duh, they are two parts. I have so much to learn.
Oddly, those curves you speak of are made up of a chamfer and a fillet to mimic the curve I want. Long story is that I know the actual curve I want (not made from chamfer/fillet) but cannot apply it to both surfaces as needed and have yet to hear back from the CAD folks with a way to do it otherwise. They will as they always have. CAD, like printing, is new to me (beginning of May) so the curve is steep. I'm a bulldog so I will get there from here, just isn't always the simplest way!
Added infill was for no other reason than my friend will put a small bolt hole in it somewhere once he has it so might helps its crush resistance ever so slightly? Since I used to make bits out of carbon with Nomex honey comb "infill", anytime someone chose to put an unplanned hole in it was simple. Drill the hole completely through, sneak a 90 degree pick through one or both side of the hole, spin the tool to ruin the honeycomb, tape up one side / hole and fill the void with epoxy. Once dry re-drill the hole and you have big strength. I suggested something like this to my buddy but as you point out, probably not needed.
Does having extra infill HURT the resulting part? I'm just a big chicken but always willing to try other steps.
With your suggestions I'm now going to
A) look hard at my x/z gantry. Never forget, I print other things with perfection (my level of perfection) so this part looking goofy is a conundrum to this old rookie.
B) fix the CAD model and
C) slice the model using your suggestions. Lastly?
D) cross fingers.
I don't have the words to thank you for this other than...Thank you! Greatly appreciated. I'll get back with you once I've given it another swing.
All the best, sincerely, PDC
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GregValiant 1,330
That's pretty ugly.
There are a couple of things going on there.
The flat piece isn't actually in contact with the second shape. Here you can see the gap between the meshes. It's only 0.05mm and it MIGHT stay together. Although computers are stupid, they are also accurate. The part has a gap so Cura is being accurate and acknowledging the gap. That needs to be addressed in CAD and the parts properly "unioned" (if that is in fact your intent).
When you have a fillet on the build plate, support is tough for the first couple of layers. I usually move parts like that up 1mm or so off the build plate. That allows the support for the first couple of layers of the radius to form correctly and actually support something rather than just being there. If it's your design you might want to consider a chamfer rather than the fillet as a chamfer wouldn't need support. That would allow you to change your Over Hang angle to 50° up from the 10° of your current setting.
In regards to the poor first layers, check your Z system and check for play on the right end of the X beam.
If there is any binding in the Z it can cause inconsistent layer heights. Z-hops can make the situation worse as the X beam moves up but doesn't come down correctly. The situation gets better as the nozzle rises on the part. I had to put a 0.3mm shim behind the Z motor bracket on my Ender to keep the threaded Z rod straight up and down throughout it's movement. Since the X beam is cantilevered - if it can be wobbled up and down on the right end it can also bind. That one is a PITA to fix as you really need to pull the X beam assembly off the top of the machine to get to the mounting screws.
Check all the Z trolley wheels as well. They are mounted with eccentric nuts so you can adjust the tension to the slots on the aluminum extrusions. You should just be able to turn any trolley wheel with your fingers.
Simply increasing the Infill Density doesn't help the strength a lot.
This is with the Infill Density at 15%, Infill Line Multiplier 3, Infill Line Directions [0], Overhang Angle 50°, and the part is 1mm off the build plate. You could park a car on this.
If you hover your mouse over my avatar you will see a motor"cycle". The only printed part on it is the Ipod mount on the left side. I'm in Florida and the mount is silky silver PLA but it has held up other than discoloration from the sun.
Edited by GregValiantLink to post
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