Tag Archives: SoM

Updated Filament Spool Holder for SoM

Posted on by Rehorst, Mark

Big thanks to Tom Klein for a great modification of SoM’s filament spool holder!

The original design used to have a printed ABS top roller and I just pushed the roller against the flanges and finger-tightened the nut.  The problem was people kept taking it apart, so I added rubber bands to pull the roller down, and a nylock nut to prevent tool-free disassembly.  Then the rubber bands kept disappearing, and Tom came up with the idea of making a heavy top roller so the rubber bands wouldn’t be needed.  He cut a new, steel top roller on the lathe and it works great!  The bolt is just loose enough to let the roller slide up and down in the slot in the frame.  The roller is heavy enough that it just falls into position on the spool flanges.

Tangle-free filament spool holder

Fun in the Booth at the Milwaukee Maker Faire

Posted on by Rehorst, Mark

Last minute decisions work out once in a while.  For example, I was going to be at the Makerspace booth at the Milwaukee Maker Faire for the weekend and wanted some examples of the sorts of things you can use a 3D printer to make, so I grabbed the usual collection of sample prints, and then I thought, “sure, why not?”, and loaded the Van de Graaff generator into the car.  It sat on the floor in the booth for about 1/2 of Saturday and I was getting a little bored, so I moved it closer to the foot traffic and plugged it in.  Wow!  Kids and adults with stunted emotional development went nutz!  They were zapping themselves and each other as if it were more fun than painful.

Sparks!

Sparks!  The VDG produces about 400 kV.

Then I found a plastic bucket and the fun really started.  We had kids and many adults who were definitely much too heavy, standing on the bucket and making their hair stand up with moms, dads, boyfriends, girlfriends, husbands, wives, partners all taking pictures.   I had to move one gentleman who was breathing oxygen from a tank away from the machine.  Fortunately, no one fell off the bucket or caught on fire, and next year we’ll do it right and take a block of styrofoam for people to fall off of  to stand on.

Kylee was ready to join the Makerspace just for this… and with that shirt, she’d fit right in!

 

Blondes really do have more fun!

Blondes really do have more fun!

Even Gordon couldn't resist!

Even Gordon couldn’t resist!

 

Last year Son of MegaMax (a 3D printer built at the Milwaukee Makerspace) went to the Faire.  This year he had two companions to keep him company- an extra-beefy printer being built by Erich Zeimantz: MiniMax XY.  MMXY isn’t complete yet, but promises to be a super high quality, high speed printer.  He’ll be operational at next year’s Maker Faire.  SoM also brought his big brother, Ultra MegaMax Dominator, named that because he is ultra, mega, maximum, and he dominates.

MiniMax XY at Milwaukee Maker Faire

MiniMax XY at Milwaukee Maker Faire

 

Ultra MegaMax Dominator and Son of MegaMax at the Milwaukee Maker Faire

Ultra MegaMax Dominator and Son of MegaMax at the Milwaukee Maker Faire

UMMD and SoM rotated between the booth and the dark room where the both printers’ UV lighting and fluorescent filament was a big hit.

UMMD in the Dark Room at Milwaukee Maker Faire 2017

UMMD in the Dark Room at Milwaukee Maker Faire 2017

We had a few things besides 3D printers at the booth.  Tony brought in some Bismuth crystals to give away, and surprisingly, they didn’t all disappear in the first hour.  Tony thinks people left them because the Makerspace logo on the info board on which the crystals were sitting looked a lot like the skull and crossbones that usually indicates poison.  The crystals do have an other-worldly toxic look about them.  Oh well…

Bismuth Crystal

Bismuth Crystal

Marcin’s LED signs on the table at the booth and hanging above the entrance to the Dark Room were also very popular and hard to miss, though I managed not to take any pictures of either.  The one above the Dark Room was so bright that if you saw it, you’ve probably still got its image burned into your retinas.

Everyone involved had a great time and we’ll be there again next year with even more cool stuff!

 

 

Chocolate Cooling System Almost Ready For Testing

Posted on by Rehorst, Mark

Chocolate printer progress continues.  This week was devoted to the print cooling system.  The chocolate will come out the extruder nozzle in a semi-molten state.  It needs to solidify by the time the next layer of chocolate gets deposited on it, and I’d prefer it doesn’t drip or sag, so it needs to be chilled right after extrusion.  The current plan is to blow chilled air over the chocolate just after it leaves the extruder.   The chilled air will come from a foam insulated box containing a block of dry ice.  There will be a blower pushing air into the box and a hose delivering the chilled air/CO2 to the print.

A couple weeks ago I got a blower from American Science and Surplus and this week I got it running by using a model airplane ESC and servo tester to drive its brushless DC motor.  It appears to be capable of blowing much more air than I’ll need.  There are many unknowns yet to test.  How much chilled air/CO2 will it take to solidify the chocolate after it leaves the extruder?  How long will a block of dry ice last when used this way?  Will ice build-up inside the chiller box adversely affect its performance?

I designed and printed three parts for this system- a mount to attach the blower to a foam box up to 1.5″ thick, a hose coupler to allow delivery of the chilled air/CO2 to the print, and a hole saw to cut holes to fit the other two parts.   The printed parts fit as if they were designed for the job!

3D printed hole saw

3D printed hole saw

Hose connected to hose coupler

Hose connected to hose coupler

Hose coupler parts

Hose coupler parts

Blower mount for air chiller box

Blower mount for air chiller box

Experiments in optics and image processing

Posted on by Rehorst, Mark

After successfully mating a web cam with my microscopes (http://www.thingiverse.com/thing:216821) and telescope (https://www.youmagine.com/designs/web-cam-adapter-for-meade-telescope-eyepiece), I decided to design and print adapters to mount my Droid Turbo phone on the same scopes (https://www.youmagine.com/designs/microscope-adapter-for-droid-turbo-phone and https://www.youmagine.com/designs/droid-turbo-phone-to-telescope-adapter) so I could shoot higher resolution stills (21 Mp) and 1080p (and even 4k) video.   The telescope adapter fits over a Meade 32mm focal length Super Plössl eyepiece and provides about 47X magnification with the telescope.  I printed a similar adapter for my surgical microscope.

IMG_0995_crop

 

 

 

 

 

 

 

 

 

 

 

 

The telescope adapter firmly grips the phone and the eyepiece.

 

IMG_0993_crop

 

 

 

 

 

 

 

 

 

 

 

 

Initial tests were a little disappointing.  The combination of the phone’s camera and the telescope’s optics has significant pincushion distortion.  The image has only been mirrored L-R and scaled down (original is 21 Mp).  Note the lack of contrast (looking through 1/2 mile of humid air) and the curves in the power line and pole, and even the grass line:

pinch test original

 

 

 

 

 

 

 

 

 

A quick search found that the Gimp has built in transform tools to correct (or create) lens distortion.

 

gimp

 

 

 

 

 

 

 

 

It only took a couple minutes of messing around to get acceptable results.  Here’s the same image with the pincushion distortion corrected (whole image), contrast stretched and white balance corrected (rectangular area).  The pole, power line, and even the grass line now look straight.

pinch test corrected

 

 

 

 

 

 

 

 

 

And here’s the final image with all corrections and cropping applied:

final

 

 

 

 

 

 

 

 

 

 

Next step: photograph known square grids through the microscope and telescope and then create and save some preset corrections to apply with Gimp.

I wonder if something like this exists for video.  Hmmmmm…

 

 

 

 

 

Son of MegaMax Enters Instructables 3D Printing Contest

Posted on by Rehorst, Mark

Many 3D printers being given away as prizes!  If I win one I’ll be donating it to my son’s school or other school or library that would like a machine and doesn’t already have one.  To do that I need your votes!

Son of MegaMax

Son of MegaMax

Please see my Instructable here:  http://www.instructables.com/id/An-Almost-Reliable-High-Precision-3D-Printer-Son-o/and vote for me by clicking the little red “vote” ribbon in the upper right corner of the start page.

Thanks!

http://www.instructables.com/id/An-Almost-Reliable-High-Precision-3D-Printer-Son-o/