Category Archives: #make

Come Learn Something

 

Tuesday meetings often turn into training night at the Makerspace.  So many members come the the weekly meeting that it can be easy to find something new to learn.  Last week was no exception when Pete gave an intro to screen printing.

Come Learn Something

It seamed like a straight forward process and I would encourage people who want to try making a tee shirt to email Pete to get checked out on the machine.

Come Learn Something

After walking the class through the basics of preparing the silk with the design. Pete set up an example print and let his small class of makers give it a try.

Come Learn Something

Chocolate Printer Cooling System Test

This week I attempted the first test of the chocolate printer cooling system.  The cooling system is intended to solidify the chocolate just after it leaves the extruder nozzle so that by the time the next layer is started it will have a solid layer to sit on.  The cooling system consists of a centrifugal blower with a brushless DC motor blowing room air into a styrofoam cooler containing a block of dry ice.  The air passes over the dry ice and gets chilled as the dry ice sublimates directly into very cold CO2 gas.  The chilled air and CO2 mixture exit the box through a port with a hose that will ultimately blow the cold air on the chocolate.  At least, that’s how it is supposed to work.  It blows air at -12C as measured via a thermocouple, but unfortunately, the air exit port ices up in about 2 minutes and blocks the air flow.

There are many possible solutions.  I can add a heater to the exit port to prevent formation of ice, or dry the air going into the box using a dessicant cannister or maybe just use water ice instead of dry ice if the higher temperature will still cool the chocolate adequately.   Maybe using an old miniature freezer with an air hose coiled inside would do the job.  It would be really interesting if I could use the waste heat from a freezer to keep the chocolate liquified and flowing.  Back to the drawing board!

Chocolate Cooling System Almost Ready For Testing

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

Chocolate Cooling System Almost Ready For Testing

Hose connected to hose coupler

Chocolate Cooling System Almost Ready For Testing

Hose coupler parts

Chocolate Cooling System Almost Ready For Testing

Blower mount for air chiller box

First Ever Test of the 3.5 Liter Syringe Extruder

My last post showed how I made a plunger for a 3.5 liter syringe.  Today’s post is the results of the first ever test of that syringe assembly including the plunger.  The goal of the test was to determine if the syringe pusher would be able to push very thick, viscous paste (sort of like melted chocolate) out of the 1/4″ syringe nozzle.  It was also a test of the ability of the previously made silicone plunger to maintain a seal even against whatever pressure develops inside the syringe as it is pushing.

I mixed about 1 liter of extra thick pancake batter to a consistency that I thought would be much thicker than molten chocolate (pancake batter is much cheaper than chocolate) and shoveled it into the syringe, then bolted on the pusher and hooked it up to a power supply:

Looking back, I probably should have loaded the syringe from the other end.

Syringe loaded with super thick pancake batter.

 

 

 

 

 

 

 

 

 

 

 

Here’s the actual test.  It gets especially interesting about 1 minute in:

The syringe continued drooling after power was removed due to air that was trapped inside the syringe.  As the plunger pushed, the air was compressed.  When the motor stopped the compressed air continued to push out the batter.  I will have to be careful to eliminate air bubbles in the material when it comes time to use this in a printer.

It only took a couple minutes to clean out the syringe after the test was done.

The pusher did its job much better than expected, and the plunger held up just fine, too.  I feel confident that this device will be able to extrude chocolate.   Now the real work begins…

Son of MegaMax Enters Instructables 3D Printing Contest

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/

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

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.

 

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

Assembled adapter on the eyepiece.

 

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

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

Son of MegaMax Lives!

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

Son of MegaMax Lives!

Side view of Son of MegaMax

 

Scrap Yard Success

Yesterday some of us went on a little field trip to a couple local scrap yards.  We met the people there and learned the ropes of how to do things right and not get hurt while digging for treasure in the piles of stuff they have laying around.  Wear gloves, old clothes, safety glasses, and sturdy shoes!  Stay away from moving cranes!

Here’s one of the discoveries from yesterday’s trip- explosion proof mercury vapor light fixtures:

A pallet full of explosion proof lamps at the scrap yard.

 

 

 

 

 

 

 

 

 

 

 

 

And here’s what can be done with about an hour to figure out how to get it apart to remove the mercury vapor lamp and ballast and  clean it up a little.  Another 10 minutes went into installing the hardware, wiring, and a 6W LED bulb.  I wouldn’t call it finished yet- the base is crying out for installation of pipes to act as feet, a little more cleanup, and maybe a dimmer switch.  Total invested: $18 to get the fixture from the scrap yard, and another $12 for the hardware and LED bulb.

Scrap Yard Success

Explosion proof industrial lamp turned into table lamp.

Further Adventures in 3D Printer Upgrades (upgrades?)

As previously promised, MegaMax’s Y-axis has been converted to screw drive along with the addition of a larger motor, DSP based driver, and 32V power supply.  The SmoothieBoard arrived and was quickly swapped in to replace the ATMega2560/RAMPS combo.  After studying and configuring the Smoothieboard I attempted a few test prints.  That’s when the problems started.

32V Power supply for Y axis motor. No regulation necessary!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Smoothieboard is supposed to read the config.txt file from its uSD card (conveniently accessible via USB) every time it boots.  That makes changing configuration very easy and fast – all you do is edit the config.txt file, save it , and reboot the board.  Firmware is updated the same way.  With the ATMega2560 you have to find the configuration variables by searching through multiple configuration files, make the necessary changes, recompile the firmware, then flash the controller.  I said the SmoothieBoard is supposed to read the file every time it boots, but it wasn’t doing it.  I’d make changes and they would not appear in the behavior of the printer.  Hmmmm.

Further Adventures in 3D Printer Upgrades (upgrades?)

Layers kept shifting in the X-axis- I expected Y-axis problems, but not X!

 

 

 

 

 

 

 

 

 

 

 

I attempted some prints and managed to get two decent ones in about a week of screwing around with it.  I tried dozens of combinations of speed, acceleration, junction deviation (smoothie-speak for jerk) and even tried different slicers.  The machine went completely nuts on two occasions and ignored the Z-axis limit switch and slammed the extruder into the print bed, gouging through the Kapton tape and into the aluminum!  I decided I needed some professional help so I got on the #smoothieware IRC channel and discovered that the developers of the board/firmware hang out there quite a lot.  After a lot of back and forth Q and A and testing someone suggested it might be the uSD card causing the problem.  I picked up a new card at Walmart, put the firmware and config files on it , booted the machine, and attempted a print.  PERFECT!

Further Adventures in 3D Printer Upgrades (upgrades?)

The new uSD card worked! The small round post is 4mm diameter.

 

 

 

 

 

 

 

 

 

 

I have made several prints since last night and they have all come out fine.  I still have a little tweaking to do and to test the limits of the machine’s performance, but I think the problems are behind me.

Next up:  X-axis redesign/build.  I’m replacing the two guide rails with a single linear guide.  I have also ordered and received a BullDog XL extruder to replace the hacked up QUBD unit I’ve been using.  I’ll be adding a DSP driver and 32V power supply for the X-axis motor, too.

After that, I have some ideas for a filament respooling machine and ways to fix the retraction problem in the SnakeBite extruder.

It never ends!