Joe's Makerbot will now be Joe's 3D Workbench

Joe's Makerbot is now Joe's 3D Workbench. http://joes3dworkbench.blogspot.com/

This has been a long time coming. I avoided it for many technical reasons, but I now feel it's time.

Joe's Makerbot (this blog) will remain with it's history and posts, but I will no longer be updating it. From now on all posts related to making, designing, and teaching will be on Joes3dWorkbench.blogspot.com. I hope you'll all visit me there. I will also occasionally post my more editorial thoughts on 3DHacker.com's blog.

http://joes3dworkbench.blogspot.com/

That is a great idea

I've got a couple loose spools that I don't know if they're ABS or PLA. I wish I had thought of the idea Joseph did. Acetone will stick to ABS, but not PLA, so it makes the perfect identifier.

3D Printing Tidbit - Hairspray, Glass, and HBP

Hairspray on glass with a heated build platform is a brilliant solution to sticking prints to the build platform with surprising effecency if it's done right. Hairspray has some properties that at heat will hold a print on the build platform. I don't remember who on the google groups recommended this procedure but I've been doing it for a while and it works extremely well:

• Get a cheap can of hairspray.
• Prepare your glass plate by coating it with hair spray. I mean soak the print side in the stuff.
• Lay it flat and let it dry. Should take about an hour.
• Spray it again lightly.
• Print ABS with a 100C degree heated build plate and PLA with a 60C degree plate.
• After the print allow the plate to cool completely and the print will remove easily.

If you skip that last step you'll pop the finish from the glass plate and you'll have to respray sooner.

I've been printing for a while on this setup and the best part is I haven't needed to re-spray the plate at all. If I ever do a little water will remove the old hairspray for a re-spray.

Obviously this doesn't work for printers without heated build platforms.

OverrideGc, Yes, Transparent PLA for Lithophanes, No.

So I finally got around to using a feature of Jetty's firmware that I knew was there, but never played with. It's called OverrideGC Temp which essentially allows you to set the temperature for printing on the printer instead of when slicing so I can switch from ABS to PLA without reslicing and it works great. I still have to re-level the build plat until I install those aluminum arms I got.

In my searching for an alternative to tan for lithophanes I tried some gold PLA from ToyBuilder labs and... it doesn't work. Too transparent. maybe I can find a thickness where it will work but I'm guessing it'll be really thick. So no gold for lithophanes. And still, I search.

3D Printing Tidbit - About Face

If done well the place where a print starts and ends on a layer should be invisible. Of course if that were the case I wouldn't have anything to tidbit. In reality there is often a "seem" running up the print, and usually it's running up the front right through all the detail which can really ruin minitures or objects with a lot of detail. My solution is to control where the seam will be to put it where it will be less noticed.

Here I'm plating some Doctor Who pawns and I've turned the all to face the back of the build platform. Since the seam will go across the front the seam will be hidden now where it won't do any harm.

I would prefer the slicer automatically put the seam in the back, and if that happens it's simple to adjust, just don't turn the prints. But until then back facing my prints is the best solution.

Hairspray on Glass

I think I've got this figured out. Since upgrading the build platform I've been trying to figure out how to stick prints to it. My goal is to have something that will stick as well with ABS or PLA so I don't have to relevel the build platform if I switch materials. Mind you it's still a problem because I don't have aluminum build plate arms. I'll be fixing that soon.

Jumping to the end for you all, hair spray works alarmingly well (for ABS, PLA testing is still in the future, but it looks good). Here's the rules:

• Get the cheap stuff.
• Spray liberally on the glass.
• Allow the print the cool completely before removing the print and it will pop off in a most alarming way. You'll think it must have not been stuck during printing but believe me it did. If you remove while still hot you might have to reapply too soon because you're taking the hairspray off.

The prevailing theory is that hairspray on glass will stick the prints. So I gave it a try first thing when I switched to a glass build plate and the result was okay, but I found myself having to reapply a little more frequently than I wanted. So I switched to ABS slurry on the glass to see if it would last longer. It didn't. In fact removing the print removed the slurry down to the glass every time meaning if I didn't reapply after every print the next one didn't stick. However that led me to the thought that maybe I was removing the hairspray by not waiting for the plate to cool. So I did and I have yet to need to reapply hairspray after a day. That means my prints take longer because now they have a cool down period, but it's worth it. Besides, I got the extra build plate so I'll just start switching them out between prints. Easy.

Building a sacrificial tower to fix your prints.

DutchMogul has done it again. I'm loving printing his latest board game, Breach. But I ran into a problem with the Star Goddess that I've seen before with ABS when narrow layers printed in isolation melt together. It's even more pronounced when I print the handle for my soap stamps. It doesn't happen if there's something else the same height printing with it. So printing 2 copies will often fix the problem.

When asking Joe Sadusk about it he suggested it was the time spend on each layer or number of shells, since I was printing with just 1. So I thought I'd do a little experiment and see what I can see. I tried different shells and different minimum layer times. The results were mostly the same, changing minimum layer times didn't fix a thing, adding shells only fixed a little.

At this point I'm thinking the problem isn't the minimum layer time, it's that the hot end never leaves the area and lets the ABS cool a bit. Sadusk said they'd tried it one time but it left droolies on the print, which I can imagine. Having a nozzle idle does cause it to drool. Unless you had a brush to clean the print head on before printing, which the Makerbot does not, that drool would just be stuck to the print. However, I thought of a workaround, a sacrificial tower printed on the build plate. I'd employed something similar before, so I thought I'd give it a try this time.

I was impressed that in Makerware I was able to add a 20mm test cube from the menu then scale it non-uniformly to make it as tall as the piece but thin so it doesn't waste much plastic.

The result, the print on the right, was the best of the lot. You can see the sacrificial pillar there too, it kinda detached and if it weren't for the anchor would have been useless, but the anchor kept it in the general area where it could serve as a sort of brush while the layer cooled. This is a filthy workaround, but it works for now. The real solution in my opinion would be if the bot were equipt with a brush and the minimum layer time didn't slow down the print but instead moved the nozzle away for any extra time. But until then I think I'll keep the sacrificial tower in mind.

3D Printing Tidbit - Don't tightly spool PLA

Got some clear PLA a little while back. Spooled it in my usual way around a spool from Makerbot. Turns out the spool I used was too tight, or maybe I spooled it too tight, and it resulted in the spool cracking into smaller and smaller segments near the end. Lots of air prints resulting from this.

In the future I'm either going to use a wider spool or print spool holder that is bigger.