Four, no, 37 months.. part 16 of ?

February 9th, 2014

Time for another blog post. At first I was been unable to post anything for about a month as I waited for my webhosting company to migrate my domain to some new servers. Then I’d finally got the blogging software caught up-to-date etc. But then this very post stretched across many months due to laziness.

As you all remember and are probably sick of reading about, I’m about a year behind on my blog. My last post led up to the events of my booth at Makerfaire NY 2012, which I had already covered out-of-sequence way before that, and after posting that I exhibited again at Makerfaire NY 2013 (real time). I’ve decided I’m not going out of sequence again – you can read about Makerfaire 2013 when I catch up to it.

But for now, we’re still at October of 2012 (even though as I’m writing this, today is actually November 15th, 2013 February 2nd, 2014 February 9th, 2014).

I got back from Makerfaire NY 2012 and unpacked.



After that, I did nothing RepRap related for about two months. Next up was finishing the Museum of Science’s RepRap. As I’m sure you remember, earlier in the year I built the beginnings of a RepRap (no extruder or endstops yet) for the Museum of Science in Boston. I brought it into the museum where they used it as a non-functioning prop for a 3-week exhibit.


Then took it home to finish it (where it sat untouched for half a year). It was now time to finish it.

First I needed to figure out where to mount the opto-endstop flags. I cut a piece of thin cardboard to use as a template for how I wanted to mount it, then once it was good I cut the same shape out of a flattened tin can.



I wrapped the opto-flag part in blue tape so it didn’t reflect, and mounted it beneath the bed.




Here you can see the mount screws coming through the top of the bed:



I cut an opto-endflag for the X-axis, and got a bit frustrated about how the raised belt on the Prusa design has the potential to touch the extruder.


Since I was giving the RepRap to the Museum of Science and knew they’d be using it on a regular basis, I wanted their hot-end to be one they could purchase commercially if something went wrong (rather than making them one on my lathe). I asked around as to which hot ends people were using that had few problems. Chris Connelly had been using a Budaschnozzle without problems for months, so I decided to go with that:




Then I spent some time trying to debug what was wrong with the opto-endstops I’d set up.


Meanwhile, I got MY RepRap up and running again, for the first time since Makerfaire.


My own RepRap was still having horrible problems with the carriage and my new extruder which required reinforcement. Three days later this abomination came out of my printer:


Well, back to the Museum of Science’s RepRap. I started putting together the extruder (not the one I’d just failed to print, but the one I’d successfully printed long ago when printing the parts for the RepRap).



..but then I found that I’d drilled the holes a bit off and needed to abandon that particular piece..

I decided that for the time being I’d instead try using a red ABS extruder that my friend Chris Connelly had previously printed for me on his RepRap (even though I’d ultimately go with a different extruder altogether). But first I needed a hobbed bolt.

I took an existing bolt, put it through the red extruder, and marked off where the exact center was with a black fine-tipped Sharpie (if I was using 4 washers on the gear side of the extruder).


That turned out to be exactly 26mm from the head of the bolt.


I marked 26mm on a new bolt, lined it up in my Bolt Hobbing Tool for my lathe, and proceeded to move the bolt 56 notches on the dial (which should be 1.4mm) into a 5/16″ spinning tap. I showed these next two videos a few posts back, but here they are again (since this is when they were actually recorded).

Here is video showing me hobbing the bolt:

…and here is video of the resulting hobbed bolt, for the Museum of Science’s RepRap:

Here it was lined up in the extruder:


Here is just the bolt itself:



The red extruder had a hole on the bottom for a PTFE insulator, but since I was using a Budaschnozzle, there would be nothing to fill that hole (and I worried about the filament sliding to the side before entering the hole). I took an old spent PTFE insulator, put it in the lathe, and cut this small insert:



(Sorry that video cut off at the end)

I inserted the insert, and connected the cold end to the hot end.


Yes, I now had an extruder!

I added the bolts and springs to hold the idler against the filament:


Then I mounted the extruder on the X-axis, and connected it up with the Extruder Pluggable Wiring Convention like my own RepRap and extruders use:




Again, here’s what the hot end looked like beneath the x-axis:


On Sunday January 6th 2013, at around 6:17pm, the Museum of Science’s RepRap had it’s first manual (and then first powered) extrusion:




Now, for no particularly good reason (other than that this happened around the same time), at this point I’d like to go on a super-brief tangent and post a picture of the best hamburger I’ve ever had in my life:


It was from a place called Tucker Duke’s in Valparaiso Florida. It was their signature burger. Those are onion rings in the middle, and the pink dressing was something about marmalade – I can’t remember. The whole thing is held together with a knife until you’re ready to eat it, at which point you scrunch it down and then start eating (I immediately wished I’d rolled up my sleeves first, because you can’t put the burger down after that). Sadly, that is very far from me, and I don’t know if I’ll ever have that burger again. I’m haunted by the picture I took of it. Mmmmmm..


(Jeff snaps out of it)

Ok, where were we? :)

Now we needed the heated bed.

Here I am talking about using tiny PTFE tubing over the leads for the thermistor for the heated bed, and then heatshrinking it all up nice.



Here’s the beautiful result of my careful work on the thermistor for the heated bed:


…and then proof that the thermistor was working:


and here’s the heated bed fully installed, working, and moving:

(I’ve said it before, but I love the fact that with my first RepRap it was a LONG time before I ever got around to having a heated bed, and then after that, I don’t even consider a printer finished until it has one. We keep raising the bar. :) )

Continuing on the rapid progress, on Wednesday January 23rd 2013 at 6:22am, the Museum of Science’s RepRap had it’s FIRST PRINT!


…and the result!


All of this was on its first try!




And guess what? It was water-tight on the first try too!



Fulfilling tradition, here I am toasting the successful completion of another RepRap, this one for the Museum of Science in Boston!

That’s all for this post. Today is February 9th 2014 and I’ve now brought you up to the events of January 23rd 2013.. so I’m a tiny bit more than a year behind, but that’s okay because I really will catch up. Honest.

Thanks for reading.

Four, no, 33 months.. part 15 of ?

September 14th, 2013

It all starts with a clean table.

That’s how my RepRap started – I cleaned off a bit of table to work on. And that’s how my setup for Makerfaire NY 2012 went. I needed a table.

In this case, I owe that table (and the room it was in) to my wife Laurie (thanks Laurie!). Last September (2012) as I was getting ready to exhibit at Makerfaire NY for the first time, I decided I needed to do a mock setup of my table. Laurie sensed my need for more space and cleaned out the adjoining “room” in the basement from where I’ve been working (which had previously held dangerously high piles of stuff).

Once the room was usable, I set up my mock table:

Here’s that same room from the other direction

I did a quick trip to Home Depot and bought new bulbs for the light in that room, a portable tool bag, some more zip ties, etc. Then I moved my RepRap to the table:

My tool bag:

I’d also pack a huge duffle bag with the larger things like the laptop and power strips.

There’s not too much narrative after this, just me going through pictures from last year to see which are worth posting.

I’d forgotten this, but I made a metal piece to rest on top of my extruder so the PTFE tube that my filament was going through (from the spool) had a place to stop before being chewed up by the extruder:

[EDIT: I found a movie about that which I hadn't included in the post initially:


Then after grabbing a blob of PLA off of the print bed, I noticed that it bent light and acted like a lens.

After the power came back on, it was back to work.

In the last post I talked about how I’d made a metal brace for the bottom of the cold end of my extruder, to more strongly hold up the M3 rods that hold up the PEEK block that holds up the nozzle.

Well, it turns out to have been a bad idea to make that out of metal (at least when combined with the other bad idea of printing my X-carriage out of PLA!). Here is what I’d noticed had happened to the OpenX carriage – it melted!

Despite knowing that the issue was caused by having a PLA carriage, I apparently printed another one, just so I’d have something to work (but that I knew would eventually melt). That’s tough to believe now, but that’s what the photos and movies show. Maybe I thought that the heat was only slightly contributing to the warp – who knows. So I built another one, and optimistically declared that it would work better despite being ugly:

Something was awfully wrong after that. I almost wanted to skip this next video, except that it does capture a desperate version of me trying to rattle off into the camera all of the theories and things that I’ve checked, hoping that I could someday diagnose what’s wrong. I’ll include it with that context: I had no idea what was wrong:

At one point in that movie I’d postulated that maybe it was because of the brittle plastic. I tested that theory next by using some other sample plastic that threw in one of my orders (thanks Johnny!). This was the first colored plastic that I ever extruded out of my RepRap:


Then later in the print I found that layers further up were printing okay, whereas the first layers had been awful.

Then was this picture.. Check out the metal plate above the carriage (look for the blue bit between the x-carriage and the metal) – you can see it going up at an angle! Clearly that PLA carriage had melted too:

It turns out I noticed it back then too:

Here’s the horrible print that came out of that. The lower layers were far worse than the upper ones:

I made a replacement support piece out of MDF instead of metal, so it wouldn’t conduct heat and melt the carriage. If I remember correctly, after the video above I held the extruder up straight while it cooled, leaving the PLA carriage somewhat flat and unbent. Then I put the MDF version on instead.

I finally decided to open up my next real spool of PLA. I used the last of the green to print an absolutely awful (but functional) spool holder, and mounted the spool.

The prints were better with the MDF (but still not as awesome as my older prints had been with a Wade’s extruder and a traditional groove-mount style mounting). The blue print was the newest of these:

Here’s another “sad xmas tree” I tried printing (which had worked great in the old days out of ABS on the Makerbot, but which I hadn’t printed well in PLA). I still didn’t, since I still didn’t have a fan. At least the bottom layers looked nice:

I printed a filament guide which replaced the metal thing I’d made:

I’m surprised to see that I tried printing a fan mount, because I didn’t use it back then:

Then I tried printing another version of the OpenX carriage, which I ultimately never used (I may have just forgotten). Still out of PLA (facepalm).

Then while trying to print a large gear, I had a problem with the large gear on my extruder (and I had to dig into the printed set of parts for my eventual 2nd RepRap):

I was later able to print this (which my eyes today don’t see as usable, but they did a year ago):

I put it back on the pile to replace the spare I’d borrowed:

At work I was supposed to do some talk, and I asked if anyone minded if I did one totally unrelated to work – I wanted to dry-run my Makerfaire RepRap presentation. Work was fine with that. I created a powerpoint presentation, packed my RepRap in my car, and drove it to work.

During the presentation I had it printing a bottle opener (out of the new blue PLA I was using). Here was the final product:

One week later, I would go to Makerfaire NY 2012 and exhibit my RepRap in public for the first time. That was one year ago.

[EDIT #2: Here's another video I missed in the initial post, of me at the end talking about getting ready for Makerfaire NY 2012:


Back then I blogged about [Makerfaire NY 2012] out-of-sequence (when I was a year behind). If you’re reading along, chronologically this would be a good time to go back and read that post (actually, read it even if you already read it – it’s a great post!):

Makerfaire NY 2012: Booth 8736 (My RepRap!)

Rather than deciding now what the next blog post will be, I’ll save that decision for after Makerfaire 2013 next week. We’ll see if I blog about that one out-of-sequence too, or if I use it as motivation to completely and totally catch up. Man I hate being behind. Today is September 14 2013, and now the blog is caught up all the way to September 30th 2012 (so I’m behind by less than a year!! :D )

If you’re within a reasonable distance to Queens New York, come see me next week at Makerfaire NY 2013! I’m booth #10895. It’s on September 21st and 22nd. I’ll be at the 3D Printer Village. I hope to see you there!

Quadcopter! Four, no, 32 months.. part 14 of ?

August 28th, 2013

Before I get into this next post, let me mention that I’ll be exhibiting again this year at Makerfaire NY 2013! I’m booth #10895. It’s on September 21st and 22nd. I’ll be at the 3D Printer Village. I hope to see you there! For those who don’t remember it, here was my post last year about my Makerfaire NY 2012 experience: Makerfaire NY 2012: Booth 8736 (My RepRap!).

Still trying to catch up on the blog. Yes I know how absurd it is that I’m talking about past events (from over a year ago) in the order that they happened, hoping to “catch up” like getting out of debt. I don’t care that it’s absurd. :) But want to know how absurd it is? The link I just gave above about last year’s Makerfaire (2012) is AFTER the events I’m describing here, yet I blogged about it because Makerfaire was cool enough to blog about out-of-sequence, and I’m now just getting close to catching up to that point (which I’ll then not cover, since I already did), and then in the present I’ll actually go to the 2013 one! That’s in 4 weeks from today, so I’d like to catch up before that if I can. What a byzantine mess!

Ok. Today is August 28th 2013 and I’m describing events from April 3rd of 2012. Here we go.

The next thing I just HAD to print was a quadcopter.

At work they had let us borrow a quadcopter (an AscTec Pelican) and it was incredibly fun. Two coworkers of mine (Reed and Neil) borrowed it with me, and we flew it enough to get a serious taste for it. I wanted to print one.

I decided to print the PL1Q Vampire (thing:17612), but with a bunch of alternate parts.

First I tried printing the regular center piece (“body”). That has some really challenging bridging, and I wasn’t using a fan. I didn’t have much luck.

I’m not completely sure on the order of these, but the first (aborted) fail I had (according to image number) was this:

Then I printed a bridging stress-test piece, thing:9804 (I still didn’t have a fan):

I also briefly tried a filament guide clip (thing:20663) on the center of the bar (which I later stopped using):

Another failed attempt (which looks particularly messy – I must have left it unattended) was this one:

So instead I printed this version from thing:18106 which split the top and bottom parts into two pieces.

Here they are together (I didn’t break off the circular pads that were only there to hold it down on the bed yet):

Next up were the arms. I couldn’t print them vertically, so I found this variant (thing:17803) that printed them on their sides:

I printed 3 more arms, and put them all on for show:

Then I printed one of the most solid, serious, strong looking pieces I could remember printing on my RepRap – the dome from thing:18106 (pl1qvampiredome_fixed.stl):

Here it is placed over the rims of the arms, holding them in place:

…and here’s what that looks like from below:

Next I printed the landing feet, which I now realize were the only parts directly from the original thing:17612 model:

The last parts were the combination motor-mounts-and-propeller-guards for each of the four arms. I used the ones from thing:18106. Here was the first one:

I was able to print two more..

Man that looks cool..

That picture of the three attached propeller guards was taken on April 9th 2012. Then I started running into problems, and I didn’t know why. Little did I know that some of these problems would stick with me for the next year or so. (By the way, it’s good for me to go through this history as I blog about it a year later, as I can start to see from a 30,000 foot view what actually happened).


Two days later I took these next two pictures. What was strange was that there was a shift in both the X and Y axes (which also happens later in the year but for a completely different reason). I think this time was a one-time problem:

As often happens after a failure, I got a bit sidetracked. You see, my favorite band is Rush, and within one week they were about to release another single from their yet-to-be-released album Clockwork Angels. In previous singles we’d seen this interesting clock face, and I decided I wanted to model it (I figured someday it might make a nice actual clock). I modeled and successfully printed it:

I used Google Sketchup for this, and because of how I pulled up the symbols, it ended up with a weird quirk that I decided to keep – not only were the symbols raised, but holes were left below it, so if you look at the back you see the symbols clearly too.

A week later I uploaded that to thingiverse on April 19th 2012 (here) on the release date of the single Headlong Flight, and someone later even created a derivative (remix) of it to make it bigger.

I tried printing the fourth propeller guard again, and had another failure. This time the extruder pushed out of the old-style PTFE insulator that I was using. (Always take pictures of your extruder during failures.. this is really the only way that I have of tracking which extruder type I was using when, and when problems started).

If you look closely at the angle of the extruder motor in this pic you can see it raised off the rails:

…which you can see far more clearly from the front:

What makes this failure particularly mysterious is that not only did it come off of the rails (which usually indicates a knot of some kind in the filament spool), but the extruder barrel also pushed out completely, and Wade’s Extruder just kept on pushing filament through (which implied that it WAS able to move plastic – there was no knot at that time):

In this one you can see the further cracking of the front oval piece of the OpenX carriage, holding a bearing:

At the end of the filament is the culprit – a plug – which pushed out the barrel (or, maybe it’s just the innocent piece of melted plastic that came out after the PTFE failed on its own):

All I can think is that maybe after the heater barrel pushed out, the solid 3mm filament then pushed straight into the glass, and the continued pressure pushed the extruder off of the rails (made easier because of the weakened oval piece on the front).

There WAS also a slight problem with the filament in the spool, but it wasn’t necessarily a knot.. It looks like the plastic here went over the side of the filament guides and around the end of the spool, which might have made extra tension which perhaps then relented. Who knows.

My brother Jon came up from Brooklyn, and while he was here I gave him his share of the large McMaster order (which had included nuts, bolts, washers, and rods for RepRaps for him, the Museum of Science, Joe Werther, and myself). Here he is cutting steel rods on my chopsaw, for one of my RepRap’s children – Jon’s RepRap:

Next up – here’s some advice: don’t wind a coil of PLA off of one spool and onto another. You’ll see why below. I decided to give this a try after seeing Ross (TINYenormous) successfully use a Home Depot extension cord spool with his RepRap. At first I set it up like this, with the filament going through a hole I drilled in the handle and straight over the back top bar on the RepRap:

I later put some PTFE tube between the handle and Wade’s extruder. Unfortunately I didn’t have a good “stop” on the Wade’s side and it later pulled the PTFE tube in and chopped up the end of it.

I printed a Greg’s Accessible extruder out of PLA (again, bad idea using PLA for this):

Then I had yet another extruder failure while trying to print that fourth propeller guard. It pushed the nozzle out of the PTFE again.

That was infuriating (if I remember correctly) because I had just made another extruder.. it shouldn’t be failing this soon..

What was particularly messy about this failure was that the solid filament then happened to go towards the back of the RepRap, and went back and tangled inside the spool of plastic.

Not yet knowing why my RepRap had started causing PTFE-based extruders to fail, I became frustrated with the PTFE-insulator design and wanted to try to make my Adrian’s Extruder Nozzle work from before. Last time my problem had been that the two bars holding up the PEEK bar had warped the holes in the Greg’s accessible extruder. I thought that if I had something strong below the extruder, maybe it could support those bars. I went to Home Depot and found some shelving bracket made of metal, brought it home, cut it to size, and drilled holes in it.

The first print with this setup was not a great success.

Three days later I tried printing an idler piece for the extruder for the Museum of Science’s RepRap. This went rather poorly too, at least in part due to the x-carriage.

That yielded this unusable part:

I also recorded this reminder for myself about what I’d started doing with the x-belt, which might have explained the extra vibrations that caused the carriage to come apart:

(or maybe it was heat from the metal plate melting things.. but I hadn’t figured that out yet).

That was at the beginning of May 2012. A month went by where I didn’t touch the RepRap at all. Then on June 10th I got up and printing again. I had stripped a PLA large extruder gear, so I replaced it with another from somewhere (not sure – maybe the one I’d made for the Museum of Science? or for my 2nd RepRap?). While trying to print a replacement, I made these videos, which were pretty important (I caught a pretty serious error on video):

If you didn’t watch that video (you should have), you missed that: A) the printer wasn’t making it to the temperature that I wanted it to go to, and B) it totally hung in the middle of a print – it stopped, didn’t do anything, and then eventually resumed printing all on its own, but now it was offset (it missed steps, making it look like an axis had skipped or something, which it absolutely had not). From a forensic point of view (and from a historical one as well), this was excellent to capture on video.

Despite what I guessed about in that video though, the ‘new software’ had nothing to do with it. Here it hung again:

Note that in that video I guessed that maybe since it was a hot day the temperature had affected the board, or maybe I wasn’t giving enough power to the board.

I tried again and failed at printing the 4th propeller guard (I won’t bore you with the long printing video that showed that).

Two weeks later, made a big discovery – finding the culprit of several of the problems that I’d had (all covered during the duration of this post). I ruled out my guess about the temperature of the board with a fan, and then found the real problem. Watch these two:

Key point from that last video: during a print, I saw the pausing/hanging happen again, but while that happened I noticed that the fan I’d put on top of the electronics (which was wired straight to 12V input) was OFF. So the power supply was clearly not providing power at all at that point – it had nothing to do with the RAMPS board. I planned to swap out that power supply with another, to see if that fixed it. That’s when I found this:

That was a scary but extremely revealing bit of info. Prior to this I had been taking all of the power for my RepRap from one molex cable from the computer power supply. I fed those wires to both the 5A and 11A inputs on the RAMPS board (which I knew was wrong when I initially did it, but at the time I thought it would be super temporary, then I just forgot about it since things worked).

My theory about what happened is that since I was pulling so much current through just one connection, it heated up, and at some point a slightly loose connection caused sparks that burned that connection. The molex connector would still conduct electricity though, so the RepRap would still function, but enough of a power draw would cause it to go dead.

Rather than replacing the power supply, I replaced the connector (and added a second one). I take one set of power from one rail, and another set from a totally different rail (that is, I don’t use two molex connectors that are on the same wire from the power supply.. I use one molex connector at most from one wire, and connect the other molex connector into a completely different set of wires coming out of the power supply).

Intermittent loss of power was clearly causing these skips, but could also have been causing the temperature to drop too low, possibly contributing to the multiple PTFE insulator extruder-pushing-out failures.

Remember that point above where I said “REMEMBER THIS POINT IN THE POST!”? I think everything from that point until this point was negatively affected (or completely caused) by that power issue. I’d also lay some serious money on THAT being the point where the burning of that molex cable happened, but I didn’t notice it for two and half months.

Here are the new connectors I made:

I describe what I’ve done:

and there’s an immediate improvement:

Results: “super good”:

Alicia confirms its “super good” status:

and more progress:

Then I noticed something that justifies my earlier statement warning you not to wind PLA off of one spool and onto another. I looked over at the yellow external spool and saw this:

The plastic had probably weakened from being rolled from spindle to spindle.. The inside part of the plastic (which was used to having a smaller circumference around the spool) was now on the outside, and the outside part of the plastic was on the inside. Add to that the fact that PLA is brittle and mine is completely exposed to humidity etc, and you get it cracking in several places.

The print continued:

And then, after three and a half months of printing (most spent trying to print the 4th propeller guard), I finally finished my quadcopter’s printed parts!

I placed the fourth propeller-guard/motor-mount on my quadcopter, and it looked glorious!

Nope, I still haven’t bought the electronics for the quadcopter, nor the propellers, nor wiring, nor a transmitter, nor a receiver (even at the end of August 2013). :( But I will!

Coming full circle to reminding you about coming to see me at Makerfaire NY 2013, here I was holding up my completed quadcopter at Makerfaire NY 2012:

There’s still enough material between this point (July 17 2012) and Makerfaire for one more short post between then and when we skip past the 2012 Makerfaire. Getting more caught up! Again, today is August 28th 2013, so I’m about a year behind. This sure feels like debt. :)