arduino, robots, cameras, and life

I’ll admit it. I went into cvs and walked out with two packages of nail files and a snapple. What of it?

Despite the weird looks from cashiers, nail files are absolutely _perfect_ for cleaning up prints. You can do fine sanding, clean up seams, or round off those sharp corners from a kapton heated bed. The best thing? It’s less than $2 for a pack of ten. Pick them up with your groceries, or use them as a cart stuffer on amazon so you can get up over the $25 minimum for free shipping.

Wow, most of them on amazon are a bad deal, but you can pick up a gross of them for $9 with free shipping!

I have never been a big believer in using kapton tape as a heated bed surface. I never saw much benefit, and whenever I used it I ended up cutting it or scratching it very easily trying to get the parts off.

When I use blue tape I generally heat the bed up to 90-110. I print the part, and then as soon as it is finished I pry it off with a chisel. This ends up with a lot of damage to the blue tape, but it is pretty cheap to replace, and easy to pull up a single strip at a time.

The turning point for me came when I tried to do the same procedure on my kapton bed. The adhesive simply wasn’t strong enough to keep the tape on the bed and it ended up bending and lifting and tearing. I knew that was not supposed to happen, so I stopped and looked at what I was doing, and realized that the point of kapton is that it loses grip as it cools. That means you need to cool the bed in order to get the part off! I feel silly admitting that it took me so long to see I was being impatient.

Now that I have that figured out I print, cool, and then generally I can snap the piece off fairly easily. I wipe the surface down with nail polish remover on a cotton ball before every print. Sometimes I still need to get the chisel out and put the tip under one edge of the piece, but once one corner pops free, the whole piece is free. No more prying from every corner.

My one complaint is that I only have 1″ wide kapton. 2 or 3″ would be much nicer. I’ve also been meaning to get some PET tape with a high temp adhesive to test against.

To be honest: I posted this to the makerbot forums. I have had limited luck on those forums before so I am also posting here. I’d like to be able to get input from reprappers as well as makerbotters.

I’m rebuilding a late-model cupcake for fablab Boston. It has had some parts stolen, and I’m looking for advice on what route to go.

The two issues are that the motherboard has been stolen and it has a mk4 extruder. I know that the simplest thing to do would be to buy a new motherboard but the direct replacement (1.2) seems to be perennially out of stock.

Then we get to the fact that it still has a mk4 extruder. Since this will be used to teach kids how to print and do 3d design, I would really prefer if it had a bulletproof hot end. I think that generally means stepper-based, either mk6, mk7, or a wades style printed one.

sooooo…
Option 1_ I can get a motherboard v2.4, stepstruder mk7 complete kit, and an arduino mega 2560 from Makerbot for $85+$229+$65=$379

Option 2_ I can get a motherboard v2.4, another stepper driver, a stepper motor, arduino mega 2560 from Makerbot and some printed wades extruder parts for $85+$92+$65+free=$242

Option 3_ I can just get the motherboard v2.4 and an arduino from Makerbot and fight with the old dc extruder for $85+$65=$150

Option 4_ I can get a full reprap-style ramps board from reprapworld.com with stepper drivers, an arduino mega, a stepper motor and printed parts for a wade extruder for $130+$16+free=$146

Am I missing any better options? I’m leaning towards option 4 currently, but I could be persuaded. Am I correct in assuming that I can’t use repg on a RAMPS setup? That would basically be a full reprap toolchain conversion.

I’m honestly fairly excited about moving to a slic3r / pronterface toolchain because repG has always been fairly buggy and I feel like the cupcake is not that well supported in recent versions.

I don’t remember who tweeted it, but I saw a tweet a week or so ago saying that the makerbot grab bags were a good deal. I looked at them and bought three. I figured that at $9 each they would be a good deal.
even if they had nothing but the ftdi cable.
I got my box today and Wow!

I got two of the grab bag #1 and one #2. Each of the #1′s had TWO ftdi cables, two early nozzles, 5 pfte barrels, 2 brass barrels, a bunch of thermistors, pulleys, a fan, and some plastic build plates. They said that the grab bag could or could not include those items, but I didn’t think it would come close to having them all!

The second grab bag was similarly stocked, with a ton of pulleys, belts, some rods, some wooden build platforms and a ton of fasteners and plastic bearings.

They said it in the description, but I want to reiterate it: If you are a cupcake operator, you should probably get this. It is a great source of spare parts that would have cost you hundreds to buy a few weeks ago from makerbot. It will hopefully keep your bot printing for a long time to come.

If you are not a cupcake operator: it’s still a damn good deal.

Thanks makerbot!

I’m not sure what’s been going on with my makerbot, but I don’t like the way it has been progressing! All week long I have been having trouble with my extruder board. I’ve been talking with Matt at Makerbot and he has been super helpful, but we haven’t figured it out yet. It will give me the dreaded “toolhead 0 : not found” error, and once finally connected it will “get tired” mid print and stop heating.

Well… today it stopped heating the extruder tip while printing, then it snagged on the print, bent the brass tube, and the hot end snapped off of the mount with a little flourish!

I’m going to try to find the drawings for the plastic mount piece that broke. Thankfully that ought to be easy enough to make by hand. After that I have to say I’m at a loss as for what I can do to prevent this from happening again. This is why they call it DIY. I just wish sometimes it was more “doing”, and less “yourself”.