Easy Buble free Kapton Tape

posted 17 Jul 2014 11:41 by David Taylor

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In this video I show you an easy way to stick Kapton tape onto a print surface such as aluminium. In the video I also show off the first version of the Printer plate I made available on Thingiverse.com. PCB Heatbed MK2a Plate (3 hole mounting) (4 hole mounting)

Heat bed

posted 2 Apr 2014 23:45 by David Taylor

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A quick update that I've been meaning to post for a couple of weeks now on my heat bed.   I've used a Printed Circuit Board (PCB) based heat bed. More specifically I got my hands on a RepRap Mk2A bed. I am able to heat this bed to 110°C but during printing it's only able to maintain about 97°C at best.     The image above shows a fairly consistent heating profile for my bed. The downside is that at the moment I only have ABS filament. With PLA, we should be able to get going in about 6 minutes and should also be much easier to maintain the temperature.   The MK2a also support 3 point mounting which I did go for. As you can see from the image below, my aluminium print surface sits snugly against the back two posts.   Having washers between the screws and the PCB Heat bed required that I cut a space for them out of the aluminium heat bed with my Dremel to ensure that the print surface plate sit snug against the PCB at all times.   I've also installed a cork backing to the bottom of the heat bed to minimise heat loss in that direction. so the entire assembly, with Cork, PCB Heat bed, Aluminium Print Surface covered in Kapton tape is shown below.   With all of the above, I was still battling to make parts stick long enough to finish printing. I tried Hair Spray (although I think I used the wrong type), but in the end I am super impressed with ABS Juice.   Basically I take about 10ml of Acetone, drop a couple of small reject ABS parts in and wait for it to dissolve. Once I have a slightly thick white smooth liquid, I pour it onto the heat bed and smooth it out with a small paint brush. Once this is dry, I can print just about anything without it ever coming off the bed. It actually makes it quite hard to take it off even afterwards, but with a bit of gentle persuasion, it pops free without breaking the part you just printed.   Tip: I lay another cork tile on top of the heat bed while heating it up. This reduces the heating time by about 15%. I've seen guys using cardboard, news paper and boxing to do the same. Effectively, just give your heat bed a blanket and remember to remove it before you start printing ;-)   Those of you that have been following my tweets where I've been saying that I want to print my quadruped leg would have noticed that I have still not done that. The universe seems to be holding me back: Power outages and Thunderstorms are to blame. (For those of you in the UK, thunderstorms in South Africa require unplugging all electronics and internet connections... ;-)

Licensing

posted 1 Mar 2014 22:14 by David Taylor

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The names in this post have been omitted to protect the innocent... ;-) I went to the House4Hack Johannesburg chapter for the first time last week. I walked in and introduced myself as David, but no one knew who I was, despite me visiting House4Hack Centurion fairly frequently for the last 8 months. One of the guys then asked if I was very active on the forums. I said I was, but they still didn't know who I was. I then mentioned that my username was Gineer. Suddenly everyone knew who I was, grind and said: "O, that gineer?". I'm not that active on the forums, but I knew exactly what they were thinking of. While I was building my Delta 3D printer, I needed a print surface to put ontop of my heatbed. I thought of using glass, but by some fluke the glass place was closed over Christmas and I ended up designing an aluminium plate cut-out. In hindsight this was less of a design and more of a form function. Have a look at my "PCB Heatbed MK2a Plate (3 hole mounting)" and "PCB Heatbed MK2a Plate (4 hole mounting)". One of the guys, who runs a shop where H4H'ers can buy bits and pieces, contacted me and said that his design looked very similar, after I offered to have a couple extra cut since I was having some done anyway. The puzzling thing to me was that the design he sent me was only similar in the fact that you could cut both out of 3mm aluminium. His Design My Design Version 1.0 At this point I wrote it off as being a bit of craziness on his side and moved on. I had the plates cut and handed out 18 of them at House4Hack Centurion. One of the guys who I gave some plates to mentioned to me that the aforementioned shop had an item marked New that looked very similar, and that he heard rumors that this particular shop had liberated a couple of designs from other members and profited from them. I had a look and sure enough, there was my plate, being sold for more than double what it cost me to have it manufactured. I contacted him and asked how my design was doing in terms of sales... Long story short: turns out he designed a very similar plate, sent me the wrong design file, originally, and took exception to me saying that it was my design. We had both designed the same plate. The unfortunate part came when he decided to publish our discussion on the forum, which obviously upset the rest of the forum members and provided me with the aforementioned notoriety. To save the House4Hack forum from further public discussion, I bowed out and gave him the accreditation for version 1. I have however subsequently added some real design features in version 2.0, 2.1 and 2.2 which is now starting to depart from the forum function to an actual design anyway. Lesson Learnt: Be careful when people send you queries, even especially when it makes no sense, because, it's probably a PEBKAK error on their side. I should have clarified at the time.

All systems go...

posted 13 Feb 2014 12:12 by David Taylor

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I had 20, 3mm aluminium plates cut last week based on the two designs I created and uploaded to thingiverse.com. I had 2 plates cut for the 3 post mounted MK2a board, for my 3D Delta Printer, and 18 of the plates for the 4 post mounted boards. The 4 post plates were destined for friends at H4H, my local hackerspace, where most people have Morgan printers, requiring the 4 post mounting system. After wasting 2 pieces of Koptan (always thought this was Capton tape, why does everyone pronounce it like that?) I figured I'd use a trick my sister, who works in advertising, where she often has to stick vinyl signs to glass and other stuff, taught me. I dripped a couple of drops, really just a small amount, of dishwashing liquid onto the plate, then wet it with water and gently mixed it with my fingers until the plate was evenly wet and slippery from the soap. I lay the Koptan tape onto the wet surface, which allows for really easy bubble removal, using a credit card, until the water dries up, and the tape takes over. Here is the finished product installed on the MK2a heat bed on my 3D Delta Printer: With all the bits finally in place I figured it was time to get some filament moving through my extruder. I had set all the values in DEFAULT_AXIS_STEPS_PER_UNIT to the same value, 167, including the extruder. Turns out the extruder needs 954 steps to push the filament 1 mm, thanks to the slightly customised Reprap pro mini extruder I now have. (A review of this coming soon). Anyway, with it all set up and ready to go, I decided to see if I could get some molten plastic squirting out of my hot-end for the first time. And so was boren: Worm 1 and Worm 2 @Gineer Worm1 and worm2? — Quentin Harley (@QuentinHarley) February 12, 2014 I am having slight problems with the balls not being held tightly enough to the trucks, but theoretically, I should be ready to print my first actual object soon. Just need to recalibrate with the new plates installed. Whish me luck ;-)