Tag: 3d printing

We’re 3D Printing!

There are things that are evidently too self-evident to bear mentioning — I’m certain I do it too. A friend of mine who taught computer programming used the example of telling a student how to get to the Bursar’s office v/s writing computer code to do it. You don’t have to tell the person to leave the room, go down the hall, down the stairs, and outside. There’s a lot of instruction humans will infer. A computer, on the other hand, will be completely stymied if you omit a few steps.

Well, 3D printing seems to be loaded with so-obvious-I-won’t-mention-it stuff. A lot of getting started guides and troubleshooting guides are out there in Internet-land — level the bed at the temp you’ll be printing, temperature guides for different materials, how to identify leveling or flow problems in prints. But to get started … there are a few vital pieces of info that seem to fall into the “so obvious it isn’t worth mentioning” category.

Loading the WanHao Duplicator i3 Plus / Monoprice Maker Select IIIp v2, you have to depress the little lever to load filament. Also — even though you’ve got a brand new 3D printer, they’ve run a test print on it. Nice way to confirm everything works … but it also means that brand new device you just pulled out of the box … has a clogged nozzle and needs to be cleaned.

Filament doesn’t start flowing perfectly immediately — add a couple lines of ‘skirt’ to your print. It does nothing to prevent warping or increase bed adhesion, but it makes a small loop that you don’t subsequently need to detach from your printout. If there are a couple of blobs before the extruder really gets going on that little loop? No big.

With three leveling screws, you are never going to get it perfect. Each little tweak throws all the others out of whack (three points define a plane, four over-define it). Get the bed level to the point you’re making little teeny tiny adjustments and you’re good.

And in Cura – all of the good settings you need to tweak up to get adhesion (primarily temperatures, speed, and initial layer height) are hidden. The “Print Setup” section defaults to “Recommended”. Click “Custom” and you’ll see settings for all of the stuff people recommend to sort poor adhesion, poor print quality, etc.

 

And some gcode to wipe off the extruder tip before printing because I want to be able to find it again:

M107 ;turn off fan
G28 X0 Y0 Z0 ; home X, Y and Z axis end-stops
G29 ; initiate z-probing
G0 X0 Y0 F9000 ; Go to front
G0 Z0.15 ; Drop to bed
G92 E0 ; zero the extruded length
G1 X40 E25 F500 ; Extrude 25mm of filament in a 4cm line
G92 E0 ; zero the extruded length
G1 E-1 F500 ; Retract a little
G1 X80 F4000 ; Quickly wipe away from the filament line
G1 Z0.3 ; Raise and begin printing.

3D Print Server – OctoPrint

When we started setting up our 3D printer, I installed Cura on my laptop … but I don’t want to leave my laptop in the office & hooked up to the printer for a day or two. We could install Cura on the server and use it to print, but we’d also need to use something like xvnc so we could remotely initiate a print job and not need to stay connected to a redirected X session for a day or two. Thus began the quest for a server-based 3D printer controller. I think we’re going to use OctoPrint on our Fedora server.

There are a few prerequisities: python, python-pip, and python2-virtualenv, and git-core (well, you can just download/extract the project … but having a git client is quicker/easier).

In the directory where you want the OctoPrint folder, run “git clone https://github.com/foosel/OctoPrint.git”

Create a user for octoprint and add that user to the tty and dialout groups.

Create a python virtual environment: virtualenv venv

Install OctoPrint into the new environment: ./venv/bin/python setup.py install

Log into the octoprint service account (interactive logon or su), start a screen session for the server, then start the server with in the screen:

su – myserviceaccount
screen -d -m -S OctoPrintServer
screen -x OctoPrintServer
/path/to/OctoPrint/venv/bin/octoprint

Then access the web service and continue setup – the default port is 5000. My next step is to write an init script so the server will auto-launch on restart … but this is functional enough to start printing.

 

Customer Service And IT Automation

A 3D printer filament manufacturer, MakerGeeks, has been running a series of awesome deals since Black Friday. We placed an order for several of their their “grab bag” packages – which I assume to be production overruns and whatever isn’t selling. We want to make a few large prototypes – if it’s an amalgamation of oddball colours … whatever, it’ll still be functional. We can pay extra to select the colour once we’ve got a finished model file.

A few hours after placing my order, I got a mass e-mail saying essentially “we sold a lot more stuff than we expected, it’s gonna take a while to ship”. Wasn’t buying Christmas presents, so waiting a while … whatever. Two weeks later, I haven’t heard a thing from them. Odd. I sent a quick e-mail asking for someone to verify that my order didn’t get lost or something. And never heard back from them. Waited another week and sent a follow-up.

Checked them out on the BBB site and found out they’ve got a really bad reputation for non-existent customer service And not shipping ‘stuff’. Sent an e-mail to all of the contacts listed on the BBB site (the phone number is unanswered and rolls to a generic message). Another week with no response, and I filed a BBB complaint mostly to increase the number of people saying “these people don’t bother answering e-mail and suck at order fulfillment”.

Additional irony – I’d subscribed to their newsletter when we placed our order. The five weeks of no communication from the company did include an almost daily e-mail with information on their holiday promotion. So they’re not bothering to ship my stuff, but they’re actively soliciting new orders!?!

What bothers me, though, is that a simple automated job would be the difference between initiating a charge-back and waiting for my order to ship. There’s an order database somewhere. Pull a list of all open orders & send a message that says increasingly comforting versions of “we haven’t forgotten about you, we just haven’t gotten to you yet”. If it were me, I’d probably include something like “We currently have outstanding orders for 25,839 KG of filament that we’re working through. The machines are running as fast as they can, and we’re shipping 2,848 KG a day. We want to thank you for your patience as we work through this amazing volume of holiday orders.”. Actual message content is almost irrelevant. The point is a few dozen development hours would be saving orders and improving the company’s reputation.

Instead I get nothing. With no faith that the company will ship me anything ever … and since I don’t want to try disputing a charge six months after it was made (had problems with that before – prepaid a CSA membership through PayPal, waited eight months for the new cycle to start, but I wasn’t on their list and they claimed to have no record of my payment. Tried to dispute it through PayPal and was told the window to dispute the charge was up … but I didn’t know I wasn’t going to be part of the new year until the first delivery!), I presented my communication and their complete lack of response to the credit card company. About 24 hours later, the charge-back was completed.

Making Soap Molds – Material Research

Before trying to print my own soap molds, I need to identify what characteristics I like in a mold. I find flexible molds easier to work with than rigid ones – I’ve snapped a number of molds trying to remove the soap.

So I am trying to find a material that will withstand heat generated by saponification. It looks like saponification can yield temperatures up to 88° C. I don’t want to buy pounds of different filaments to test them out, but GlobalFSD offers “sample” size filament cuttings that are perfect for experimentation or small niche products (e.g. printing glow in the dark mailbox numbers).

One material included information about temps for printed objects, so I’ve contacted the other manufacturers to see if they provide any sort of guidance.

Material Max C Min C Notes URL
NinjaFlex 65.5 -30 https://www.globalfsdusa.com/ninjaflex-by-fenner-drives.html?category_id=20
CrystalFlex  – – Food safe https://www.globalfsdusa.com/crystalflex-tm-by-formfutura.html?category_id=20
FilaFlex https://www.globalfsdusa.com/filaflex-by-recreus-1-75mm.html?category_id=20
FlexFill 230 -40 https://www.globalfsdusa.com/flexfil-98a-by-fillamentum-1-75mm.html?category_id=20
F41 Flex 75 -20 https://www.globalfsdusa.com/f41-flex-tm-1-75mm-black-polyolefin-filament-by-forefront.html?category_id=20

Making Soap Molds

I want to design and print my own soap molds – special holiday bars or pre-stamped bars. We’re still working on setting up the 3d printer, so haven’t tried anything yet. I have a few downloadable soap mold forms bookmarked (https://www.thingiverse.com/thing:1806226/apps happens to be up in another tab now, but search thingverse for ‘soap mold’ and you will find quite a few).

The trick will be finding an appropriate filament — one that won’t melt at soaping temps (something I need to better understand) but can still be extruded at my printer temp (190-250C). Preferably a not-too-rigid filament with a little bit of flex. That’s trial and error – expensive, too, when buying whole rolls of filament. I found http://globalfsd.com/ (there’s both a US and European site) that sells small quantities of many filiments, and I’ve purchased a bunch that *seem* like they might work.

What I planned to do until I can identify a perfect filament for non-melting and easy to remove soaps is create positive forms on the 3d printer (essentially print what you want a bar of soap to look like) and then google up a procedure for making a silicon mold (uneducated guess is glop some silicon ‘stuff’ onto the positive form to create the negative silicon mold).

For anyone wanting to play with a 3d printer without dropping a couple hundred bucks on it: check your local library. Ones around here are building “maker spaces” with 3d printers, embroidery machines, engraving machines, large format printers, etc. You pay for consumables (i.e. filament in this cae) but gain familiarity with the machines before deciding to invest in one.