Kitchenaid Pasta Roller shear pin replacement

The Kitchenaid Pasta roller attachment is useful but after time is gets dirty and the temptation is to put a rag or other object in to clean the rollers whilst its running.   This can lead to a jam and to stop the main machine self destructing, the Pasta roller has a 6mm brass shear pin that breaks before the main machine does.

Kitchenaid don't sell a replacement part but you can find 3rd parties sell them online for around $30AUD at time of posting this.  Trouble is you have to wait 2 weeks for this part.

This print is for those that want to save $30 and get the machine up and running immediately.

By chance a 5mm stainless bolt head has the exact same dimensions as the brass hex nut used on the Kitchenaid.

Edit (a few days after posting): There is a chance if you don't have a 3d printer you can use the existing plastic bit eliminating the print and punch out the broken brass shear pin and then use the M5 technique as described below.  (however I tried for a bit and could not punch the brass bit out..if you don't have a printer you may try harder than me)

To remove the original sheared brass pin, unscrew the three long screws on the outer shell of the drive side. (no need to unscrew the 3 smaller screws on the circular drive itself). Use a flat blade screwdriver to lever the broken shear out.  There are lots of YT videos shared by others how to do this if you need more help.

Purchase a 25mm long M5 bolt with 2 nuts (Bunnings in Oz sell a 10 pack of bolts and nuts for $12)

Tighten one nut against the other in roughly the configuration of the photos.   I got lucky but you may have to file/grind one nut so the hex shapes align and fit into the 3D print.  

Now the original brass 6mm diameter shear pin has a shear strength of around 6,785N but the  5mm stainless threaded bolt has shear strength a little higher around 7,600N.  To drop this down a little I filed a shallow grove around the bolt to ensure the shear would happen roughly at the same torque as designed.  You can obviously make a deeper or shallower groove if you feel you need this thing to fail earlier or later in case of a subsequent jam.  Since it is so cheap and quick to replace, I made my groove deeper as wrecking the gears in the main machine will be a much more expensive repair.

Push the 2 locked nuts into the print…should be about hand tight half the way and then light tap to seat such that the head of the bolt matches the original shear pin.  (the end of the bolt should be recessed about 2.7mm from the end of the 3D plastic part) 

Then push the new shear pin into the roller…should go about ½ way by hand then use a socket and hammer to lightly tap it till fully seated. 

Reassemble and enjoy…

PS There is easy fix for the cracked roller scrapers whilst you are fiddling with this.  You have to disassemble the device further by loosening the 4 long bolts…to do this you need to remove the adjustment knob first.  Do this by hammering a small screwdriver in to lever the cap out.  See the photos for the sequence.  Once you have access to both side of the long bolts, loosen the nuts just a few mm…do not remove the nuts otherwise it is a nightmare (well difficult) to reassemble.  Loosen the nuts so you can just remove the scrapers.  If you loosen too much the sides fall out.  Once out use some pliers to break off any remaining plastic from the scrapers.  Then place the scraper side (the one with 3 little holes) in a vice about 5mm and put a slight bend to compensate for the missing plastic.  In the photos I have removed the plastic from just one of the scrapers as the other still functional.  Reassemble and job done.