I tried print runs of the test pieces with the white filament. 3 runs and I still had problems finding tunings to allow the clearances for fitting let alone smooth operation.
So I have a bunch of miss-matched parts that don’t fit together.
The tuning seems to be per spool so might try test print with the green. But then it does it make sense to match the white axle with the green bearings?
Seems quite fiddly then to tune to get a working feeder, let alone a batch of 8mm and then on to wider feeders.
So, I’ll opt for a single colour and start with green 8mm.
I’ll report progress against tag “PushPullFeeder”.
A mentioned in entries earlier, I opted for this feeder.
I got over my ickiness about green filament. But have had all sorts of problems printing it.
Finished my while reel, not to mention the run with red filament for the incumbent feeders for the PnP. No problems since the rewiring with the new flat cable and board on the extruder.
But this green filament?! A number of blockages and therefore failed runs. Obviously I had to unblock the blockages.
So when I contacted FlashForge, they were very helpful. They told me to unblock the blockages.
So I made a number of unblocking of blockages and then the gem appeared to be use 200oC and not 220oC?!
Of course, that meant I could not get the rotten print to stick to the bed. So I am trying with 205oC but not sure why dropping the temp helps. We’ll see. Print underway.
Running the destructions for setting up of this feeder option.
Having had to go back to grasping 2020 option, I decided to set up for a real run.
I printed a batch of test items, to find none of the test hubs fitted the axel.
I also noticed on the 4020 grasping feeder body I had printed, the posts were a little off round. Now that could be an artefact due to the precision of the Finder or shrinkage. I did set the wall thickness relatively high, so I am going to go with shrinkage and so drop the wall thickness – can’t do much about the precision of the Finder.
I may get by doing all the test prints of the feeder itself on the Finder and then go into the makerspace to use the Sidewinder X1 for the production run. The Sidewinder is what I have used for most everything else on the PnP build, baring the feeders (so far).
Posted in PnP on August 3, 2021 by asteriondaedalus
First pass, “dog” brittle and bore of dog too tight
Second pass, “dog” rotated on bed to direct “grain” around the “pin” and internal compensation tuned to get a good fit of the bore of the dog
Darn dog got me again. If you rotate the dog on the print bed, you either get one pin break or the other, since you can’t rotate it into a position that avoids the “grain” problem. Probably needs a different print technique (like resin) or give up.
In fact, I worked out its as much to do with the thinness, since about an hour later that this video, I managed to break the other pin with not that much flex, and likely due to the cyclic stress.
Posted in PnP on August 3, 2021 by asteriondaedalus
So above is the test fit of the feeder, freshly off the 3D printer. Note, dropped the spool holder and opted for 4020 grasping – all tailorable using the parametrised model.
Tight fit, as the extrusion is not actually OpenBuild standard and closer to t than v slot it now seems.
Still good tight fit.
But, alas, when I went to put this setup against the assembled PnP, it turned out that the 4040 leftover extrusion was short by some good percentage of a cm.
Note we do recall that the vendor struggled delivering the right order and some pieces were not all of the required length, so maybe one of the 4 pieces of 4020 x 300mm may be long enough, but I may again need go back to the drawing board (arrrrrgghh! no they weren’t).
CrrRRAAAAaaaaappppp!
So I will change back to a 2020 grasping option in the one above.
In the meantime, I am also trying the following one:
Which is actually from here. Though the story and pictures are well behind the actual design release here. That final design comes with a reel holder. But it’s also designed in FreeCAD. It it’s parameterised as is the top one, but I had to delete the reel spook holder elements out of the model, to be left with the one above. So, options. I want to trial these options before I settle on one or the other. So I’ll have a gaggle of feeders to play with by the end of the week.
Noting I have printed out and like this one for shorter strips, and not when using reels of SMD.
Posted in 3D Printing, PnP on August 2, 2021 by asteriondaedalus
I have printed out a couple of 8mm and a couple of 24mm PnP feeders from the source design.
But I am also printing out few other feeder types to trial them.
Printed out a simple feeder. Seems good enough for those short strips of samples you get from aliexpress. Just need to fiddle with the cover strip. Actually works a treat, so I am looking for software that allows you to design compliant mechanisms. Found one or two packages, so I will dabble.
Printed out a ploopy feeder, to find it’s got a roller-blade or something or other bearing. Still trying to find the type, but I’ll take a punt from the dimensions etc. Another not bad one for strips, you have to fiddle with the plastic cover etc.
Quite interested in the Buddha tape feeder. Tape come up from beneath and between the two drums. So very good for spools and so happily will work with the spool holder on the manual PnP.
So called pushpull feeder (without the spool holder). Is the one I like to replace the supplied feeders, as you can print it without the spool holder – since the OpenSCAD file is heavily parametrized. Including, would you believe, either having a extrusion mount (of any size extrusion) or screw down. Very clever.
What was not so clever was I went to look at a test fitting this to my PnP. The tuning parameters default to fitting OpenBuild V-Slot. Turns out the 4020 I have is V-Slot and the 2020 I got, from the same vendor, is T-Slot. So a little fiddling with the parameters required to get it to sit properly … but that extrusion vendor is the gift that never stops giving, right?!
Luckily, part of the cockup from the vendor is, because 4 x 4020 x 300mm were sent, I can swap out the two 2020 (and since it’s t- and not v-slot) that are need to mount the incumbent feeders with the 4020 v-slot. The feeder base plate, with 4040 rail hugger and no reel is:
I did have a quick look at adding a t-slot option. But some other time. The OpenSCAD for this is a brilliant example of parameterised code, so have a look – even if you don’t want to build this widget.
So try to image the following with the 2 parallel 2020 rails gone and a single 4020 rail, with the thang immediately above attached. Just a tug of a lever and no fiddling with the incumbent feeders. Which require a tug on the tape and a twisting of a knob.
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