Most people would say this was caused by an over excited person, whom, upon waking early and discovering the complete print decided to not follow the correct drying / washing procedures in order to get it finished quickly!
I, err, disagree…
Either way, I now have a firm grasp of changes needed to the CAD model and also the supports needed in the slicer.
Those changes are fairly substantial, so I expect it’ll be a little while for my next update, happy to document them also if anyone’s interested.
Freshly dried and washedPerfect sizeA quick comparison
Not much of an update, I put a shorter USB cable inside so thought I’d take some pictures of the top of the USB cable wiring…..
I’ve not installed heatshrink yet on the sticky-outy USB Pins – this WILL be needed to provide strain relief – being truthful, I hadn’t expected it to work first time so didn’t bother 🙂
Spent a few hours this week adding an internal USB Hub, getting ready to start on a basic instruction sheet for the kits
As can be seen – you can’t see it’s modded externally (well, other than the keyboard). Both external USB ports still work and internally there’s a free USB port for a USB Stick 🙂
Had a little bit of a play with the daughterboard to see if there’s any possibility of putting a ‘push push’ SD card inside…
Unfortunately it isn’t without chopping at a couple of supports inside. I’m trying to keep my Next case fairly minty – untill it’s possible to get another, i’m going to avoid this mod.
The reasons it won’t fit – The case was designed with two ‘helper’ guide rails for the SD card – shown in yellow in the images above. Those rails stop any push-push mechanisms from working – there’s just not enough mounting depth for the card reader.
Now, if someone were prepared to snip those rails off….then it’s entirely possible to knock up a new daughterboard……I’ve already done most of the EDA before I thought to take the next apart and check 🙂
Not much really – Shift Lock keys just arrived off the slow boat. The pinouts are confirmed, I’m going to hit ‘go’ to manufacture after another quick check on the PCB
Also, from a bit of researching, i’m not so sure the Diodes are needed.
I may have to make two batches of board, one with, one without
After spending a while lining up the buttons and generally making the PCB layout a bit tidy, I figured I’d print a 1:1 and see just how well it aligns….
Err, doesn’t look great does it….The first layer went down lovely, then at some point during these first 6 or so layers, a shift happened, there’s some blobbing, and, well, it ain’t too pretty.
First thoughts are many expletives, followed by a ‘ah well, that was a fun experiment’ resignation.
The rails aren’t perfectly frictionless in their moving, but they aren’t bad either..I’ve seen worse on automated production lines….Could I be experiencing STICTION????
If so, that’s gonna be some mechanical engineering stuff i’m going to have to figure out…Whilst ‘fun’ trying to calculate stuff with excel, wikipedia and various internet forums (are the MGN12 ideal for this job? – who knows?)…..I don’t fancy being bored, typing crap out on a computer (yes, i’m blogging, typing stuff out on a computer, hopefully not crap), I want to get stuck into tinkering, printing…..
I try another print and just stand and watch……
I luckily and quickly notice an odd ‘cyclic’ type of motion happening with the pattern laying down, almost a tiny figure of 8 type of motion happening on the print head with respect to the bed…..
I have a look underneath to see what’s causing it, maybe the bearings are wobbling, or i’ve not tightend the rails properly?
In summary –
Tighten the belt holder holding nuts when you re-assemble the thing! these ones shown below…..
Yes, tightening these two solved my odd pattern issues and layer shifting
Ok, the rails are on and working a treat, kind of…
The right angled fittings I purchased to secure the 20×20 extrusion to the 40×40 have some little tabs on them, I can’t find any readily available way of securely making this connection with off the shelf parts so i’ll have to grind down one side’s tabs…
The slight amount of pressure this tab is putting on the extruision is enough to twist it and stop the MGN rails from running smoothly!
A secure 20×20 extrusion. But slightly twisted due to the small lump
View from below…if I add a little drop down to the right hand carriage, it’ll be easy to re-use the existing limit switch by mounting it on the side of the 2020
Close ups of the existing limit switch and the protrusions on the right angled mounting block.
Overall, minor things , but shows you should plan things a little in advance and test fit stuff before ‘going for it’
Fortunately this is nothing a quick angle grind and carriage print can’t fix….which means re-assembling the original printer to print a new bit, D’oh!
During the unboxing, a bit of an oddity showed up, the build plate didn’t look level at all
taking a picture from the front, looking in, it’s clear that the height between the plate and that block thing is quite a bit more on the right, than the left
