Son of MegaMax – Milwaukee Makerspace

Chocolate Cooling System Almost Ready For Testing

Rehorst, Mark — Sat, 01 Aug 2015 18:56:29 +0000

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

Hose connected to hose coupler

Hose coupler parts

Blower mount for air chiller box

Sunday Morning Project – A 3D Printed WebCam Mount for a Telescope

Rehorst, Mark — Mon, 18 May 2015 00:49:28 +0000

I recently acquired a new eyepiece to replace the damaged one that came with the Meade ETX-90 telescope I bought at a swap meet last year. I decided it needed to have a web-cam mount so I designed and printed one that is a variation of a previous design for a microscope. It took about 20 minutes to recreate the CAD file in DesignSpark Mechanical, and about 90 minutes to print on Son of MegaMax.

This thing has an odd shape to accommodate the odd shape of the camera. I designed the adapter in two pieces so it could be printed without any support material. After printing the two pieces were glued together with a little super glue.

Unassembled 3D printed WebCam adapter and eyepiece.

Assembled adapter on the eyepiece.

The adapter fits over the barrel of the 32mm fl eyepiece and stays put.

I shot a short video to test it and it works perfectly! The cars driving by are about 1/2 mile away.

If we ever get a clear night I’ll try shooting Jupiter or Saturn and then run Registax to enhance the images.

Files are here: https://www.youmagine.com/designs/web-cam-adapter-for-meade-telescope-eyepiece

Sometimes you gotta think outside the vase!

Rehorst, Mark — Mon, 27 Apr 2015 04:41:51 +0000

I found this nice vase on Thingiverse and printed it at 75% scale a couple weeks ago.

75% scale vase looks fine from this angle…

It came out pretty good except for the area near the bottom where it was overhanging. 3D printers don’t handle overhangs without support material very well. I tried reslicing with support material added, but didn’t like the way it looked in either Cura or Slic3r so I didn’t try to print it again.

Overhang caused poor print quality for the first 6-8mm of the vase.

Then I tried printing it upside down- the overhang is much smaller.

100% scale vase printing upside down.

About 12 hours later, here’s the result: perfect!

The two vases, bottoms up- the 100% scale vase is perfect!

Son of MegaMax Lives!

Rehorst, Mark — Fri, 03 Apr 2015 20:48:46 +0000

MegaMax was a great 3D printer, but it was time for some changes. He was difficult to transport because the electronics were in a separate housing with many cables to disconnect and reconnect, barely fit through doorways, and required a positively gargantuan enclosure to keep the temperature up to control ABS delamination. Though it hurt to do it, I tore him apart and did a complete redesign/build into a form that is more like what I would have done had I known anything at all about 3D printing when I started building MegaMax.

I reused what I could including a lot of the 8020 extrusions in the frame, the Z axis screw assemblies and drive belt, and the X and Z axis motors.

Changes include:

ball screw drive Y axis with high torque motor- precise but noisy
linear guides in X and Y axes instead of 1/2″ round guide rails and linear bearings
SmoothieBoard controller instead of Arduino/RAMPS
BullDog XL extruder and E3D v6 hot end
RepRapDiscount graphic LCD control panel
narrower frame design without giving up print volume- easier fit through doorways!
polycarbonate panels to enclose the print area yet provide a clear view of the print
electronics in a drawer for easy service and transport and neater appearance
DSP motor drivers and 32V power supplies for X and Y axes
Liberal use of screw terminals to make servicing easier
Modular X and Y axes that can be removed for service and replaced in minutes.

SoM will be making his public debut at the Milwaukee Makerspace very soon…

Son of MegaMax electronics drawer

Side view of Son of MegaMax