Meanwhile it seems to me that many people get a 3D printer, then try to find a use! Of interest might be resources to help design whatever it is someone might want to make, perhaps including building blocks that can be scaled and merged etc. I presume there must be such resources? I haven’t looked because whilst interested I don’t currently have a project. I do have something I bought that had been printed to order (a box to fit a SCSI SDcard board), and it was that that prompted my own stirrings of interest.
If you look at their terms and conditions, they say that you can licence you designs in any way (most are licenced under Creative Commons Attribution Share-Alike Non-Commercial), however Makerbot (who own Thingiverse) impose a condition buried in their terms and conditions granting them an indefinite irrevocable licence to use any posted design in any way without attribution.
Since the Attribution and Share-Alike terms are not preserved thas allows Makerbot to claim anyone’s designs as their own!
As @Innocent_Bystander says, it makes sense for this thread to be merged into the 3D Printing and its adaptations thread, and then closed just leaving a message and link here to direct people to the other thread.
I have finally got a replacement Z-stop sensor and put it into my printer. I also bought a thicker sheet of aluminium for the printer bed.
I suspect that there may have been something wrong with the previous sensor. It is doing much better now - much more consistent, and have printed out all the pieces for one level of the rack.
I also have bought 10 replacement nozzles. A few problems with extrusion (blockage for some reason part way through a print - with the filament at the hot end being crunched up into a sort of zig-zag mess), but generally better than it was.
The thicker aluminium sheet is, perhaps, too heavy. When the Z-motors are not powered up (which is between prints) then the bed often just slowly sinks downwards. But the first layer is sticking much better than before.
So some progress!
Finally getting some results from my printing. I am trying a number of designs for racks - this is one that I quite like - it’s not quite as I want it, and the finish is experimental, but it basically works. The idea is to avoid having a shelf (which itself can pick up vibrations), and to make it of sound-deadening materials. Obviously the main material in this case is PLA (though I will try PET-G), but most of it is hollow, but sand-filled. That deadens noise quite a lot. There is sound-absorbing material between the layers. I am working on another design which has the same legs (fairly complex spiral) but is a little wider supports, and a couple of braces between the supports. Much experimentation to see which works bets.
Possibly - the most recent version has a little more - but I’m not sure how much benefit there will be for that. Obviously a layer for my NAP500 would have to be larger.
The intention of the design was to avoid the use of shelves, because they can pick up sound vibrations from the air. I wanted the frame to be fairly minimalist - I want it to disappear as much as possible. And of course it should not, as far as possible, transmit sound from the floor. Hence each layer is separated by sound-deadening material, and the sand filling absorbs vibrations in the structure. Certainly knocking on the frame gives a very ‘dead’ sound, so I think that at least the the high and mid frequencies are absorbed effectively. The spiral legs are an experiment - partly because they look interesting, and partly because they give a little compliance in the vertical structure, to try to increase the path any vibrations must take, and so increase their absorption. I also have designs where those legs are simple (hollow and sand-filled) cylinders. Not sure which is functionally better.
I haven’t worked on the feet yet - those in the pictures are just simple feet with no particular merit - no leveling ability, for instance, and only vibration absorption between them and the first layer.
Yes, I could do that.
One thing that puzzles me is that it takes longer to print a hollow thing than a ‘solid’ one. Not sure why. There is more travelling time, perhaps, but that still doesn’t really explain it.
I have absolutely no experience of 3D printers, 3D printing or the cost of raw materials used in the process.
As a matter of interest, roughly how much (in terms of raw material used in the printing process) would it cost to print off one of these shelf layers, and have you created this particular design yourself or obtained the design elsewhere?
I designed and printed them myself. Material costs are not huge - probably £20 to £30 a layer, plus about £1.00 or £2.00 in electricity. The biggest problem is the time - it takes something like 4 or 5 days to print one layer - though I suspect that someone who knows more about 3D printing than myself (not a hard target to beat) would find ways of speeding it up. I haven’t tried recently to do that because I have had huge problems in the past trying to print these. I have about 10 layers and part-layers lying around where the print failed at one point or another. I also have several different designs lying around, and am working on anther - though I think that I might not use the new one. Then there is the finishing afterwards - sanding, filing, filling etc., and those spirals are a real pain to clean up because there are overhangs that are not supported.
But it is interesting, and I’m hoping that the result will be good. I have spent the best part of 4 months from when I ordered the printer to get where I am now. So arguably not a good investment in time. Fortunately, I have some of that going spare - and most of the time is just leaving the printer to do its thing, checking up on it periodically.
I might revisit some of the design decisions - I definitely want it to be sand-filled because that really makes a difference to its sound-absorption capability. I have put in some internal stiffening walls, but I might be able to remove some of those. Lots of ideas, but each of them take about about a week to realise and test.
Unsupported overhangs up to 45° should print cleanly in any material at and any print speed, provided the layer height is no more than 1/2 the nozzle diameter. For this job I assume you are using a larger nozzle (at least 0.6mm rather than the common 0.4mm size).
I’m using Tronxy’s slicer, which I think is based on one of the more commonly available ones. There are some problems with it on occasion. The other I have tried is Cura, which is often OK, but sometimes seems to think that the first layer is about 1 centimetre up off the bed. That doesn’t seem to work out well, on the whole. I’d like to get that to work better, because I have found out how to control it. Though the Tronxy one has lots of control parameters. I’m a little nervous to mess with things at the moment, because it is printing pretty reliably, whereas I was having severe problems before. I have had to replace the Z-sensor, and I have replaced the printing plate with a larger and thicker piece of aluminium. It might be one or other of these changes that have improved the reliability, because it has been printing well since then. The bed adhesion has been very good (I bought a printing mat/surface to stick to the aluminium).
There are so many variables that it is hard to figure out which ones matter.
The nozzle is 0.4mm size - and layer height is 0.2. Do you recommend a thicker nozzle? That could make sense, but wouldn’t it mean rougher vertical surfaces?
I have no experience of Tronxy’s slicer, I can’t help you with that. I do however use Cura (I assume you have the setting “Automatically Drop Models to the Build Plate” turned on in Cura).
Have you considered separating the helices from the platform parts, that way you can speed up the main frame (which is easier to post process) independently from the more tricky helices. I would also suggest ‘stretching’ the helices vertically.
What are you doing to make allowance for, or to prevent, creep due to long term loading of the material?
