Frostruder MK2 Assembly



The Frostruder MK2 is a pretty straightforward build. Almost all of the parts simply bolt together. There is no soldering, and the most electronics work you'll have to do is cutting some wires to length and then stripping them. You will have to do some simple, non-critical cutting of vinyl tubing as well.

The basic process is to prepare the various parts, attach them to the appropriate pieces, and then bolt it all together. The last step involves cutting tubing to length and then attaching it to an air compressor.

Stuff You'll Need

The following things are not included in the kit:

For running the Frostruder

  • Air Compressor
  • Extruder Controller
  • Something to extrude (frosting, etc.)

For building the Frostruder

  • 2.5mm hex key
  • micro screw driver
  • adjustable wrench (2)
  • file or sandpaper
  • wire cutters/strippers
  • phillips head screwdriver
  • ruler
  • wood glue
  • lacquer/shellac/sealer (optional)

The Kit

Here are the various things included in the kit:

Lasercut Parts


Syringe / Solenoids / Tubing


Stopper / Zip ties / Connectors


Syringe Clamp Hardware


Nuts and Bolts


The Build

Prep Work - Port Orientation



The first thing to do is to prep the solenoids. The solenoid is two parts: the coil (top) and the valve (bottom). These can rotate somewhat independently. You need to rotate the top part so that the wires are facing the 'IN' side on one valve, and the blank side on the other valve.

Prep Work - Connector Installation


Installing these now will save you a ton of effort later. Screw them in by hand and then give them 2-3 rotations with the adjustable wrench. Enough to get it nice and tight, but don't mangle the plastic connectors.

Prep Work (optional) - paint/seal wood

If you are going to be extruding foodstuffs or anything else you wouldn't want to soak into the open wood if it spills, now is a good time to paint/seal the wood pieces. You can hang them from a piece of thread like a mobile to easily spraycoat them outside. You can also wait to spray it once it is all bolted and glued if you wish, but in that case grab some scrap tubing to cover the ports since you won't want to get it into the solenoids and solvents in spraypaint are likely harsh on the vinyl tubing.

Attach Valves to Syringe Bottom


The valves bolt onto the syringe bottom using the short pan-head (silver) screws. There are 2 important things to get right during this step (see picture!):

  1. That the valve wires are facing the back of the piece (with the tabs)
  2. That the valve marked 'IN' is on the left.

Attach Left and Right Sides


The sides bolt onto the syringe top and bottom parts. Its easiest to bolt the bottom one on and then bolt the top one on. Don't tighten it up too tight yet, or the next step will be difficult.

The text should be on the outside.

Attach the Back Side


The back side should slide on as shown. If your bolts from the previous step are too tight, it may be difficult to get on. It has two t-slot bolts.

Attach Bottom Piece


The bottom piece pulls it all together. Mine was a bit tight, so I sanded the tabs. It also may be difficult if you tightened bolts too hard in the previous step.

Apply Glue to Bottom Piece


The bottom spacer makes for a flush mount to the MakerBot Z stage. I recommend gluing it on for a nicer end result. You can also glue all your other wooden parts together if you're feeling badass.

Clamp Bottom Spacer


Keep it all together with the M5 bolts provided (and you'll make sure you don't lose them in the process!) You'll need those bolts later for attaching it to the extruder platform, so this is the safest place for them.

Cut Tubes to Length


I cut my tubes to 45mm which was a bit too long. 40mm is probably just about right. Ballpark it and you'll be fine. You can use scissors, a knife, or wire cutters. Its very easy to cut.

Attach Tubes to Tee


On either end of the Tee you'll want to attach your newly cut tubes.

Attach Tubes to Solenoids


Attach the tubes to the solenoids with the open tube pointing towards the top of the Frostruder (I bent it back for this photo)

Cut More Tubing


Cut the tubing to roughly 12" and 8". The 12" piece will connect to your syringe and the 8" will connect to the compressor. You can cut them to different lengths if you like.

Insert Tube into Stopper


Insert one end of the long 12" tube into the stopper as shown. It will only go a short way so just press it in as far as it will go and don't force it.

Apply Clamps


Orient the two clamp parts properly so the screws go outside the flange and bolt them down. No need to go crazy as we will need to take them off to fill the syringe later.

Snap Syringe into Frostruder


The syringe will snap into place in the Frostruder. Give it a try and see how it feels. When you unsnap it, make sure you pull from the bottom first to avoid damaging the syringe tip.

Attach Syringe Tube to Tee


Push the syringe tube over the last port on the tee. This is where the pressure comes in and goes out.

Attach Tubes to Input/Output


From the front, the long tube goes onto the left solenoid. This is the pressure input tube. The other side is the exhaust port. If you have tube left over, you may want to put a tube on here to direct it away from your work piece.

Use the included zip ties to keep the tubes in place. Do not over tighten as you will pinch the tubes and reduce the air flow.

Attach Extruder Controller

If you're installing on a Thing-O-Matic, skip this step — leave the extruder controller in place, with the other electronics below the build area.


The extruder controller bolts onto the back of the Frostruder as shown. Due to a manufacturing error, some of the holes are not properly spaced. You may need to enlarge them slightly for a nice fit.

Bolt the electronics on using the M3 x 16mm bolts and supplied spacers.

Trim Solenoid Wires

If you're installing on a Thing-O-Matic, definitely skip this step or you won't have enough wire to reach the extruder controller!


Hold the wires up to the screw terminals and cut them to about 2" past the screw terminals. Strip about 1/4" of insulation from the ends.

Wire up Solenoids


Wire up the solenoids as shown in terminals A and C. The polarity is not important. Just make sure that the solenoid gets attached to the mosfet on its side.

On Thing-O-Matic, wire the "Pressure" solenoid to the "FAN" port and the "Relief" solenoid to "EXTRA"

Attach Compressor Coupling


Included in the kit is a male quick connect coupling. This is a standard and very simple to use coupling. Other styles of connectors are beyond the scope of this document.

You can purchase a mating connector from 6534K16 is a compatible part with male NPT threads.

Assembly Complete!


You're done building the Frostruder MK2!

Next Step: Usage

Head over to the Usage page in order to learn how to use your awesome new device.

Unless otherwise stated, the content of this page is licensed under GNU Free Documentation License.