Pre-print Mech. Test

Posted on April 30, 2011

After constructing the RepRap huxley, I started to test the mechanics of it with the motors attached. I love systems engineer 🙂

Motor Overheat

Problem 1: X-axis motor heat was really high which caused the X-axis motor rack to melt and thus causing the tension of the belts to bend it which consequently caused the belt to keep slipping off the cog, thats when it caught my attention :-P. ( See photo below)

Solution: Take off the motor rack and place it flat on a table. Heat it up with a blow dryer until its pliable. Put pressure on it evenly until it flattens out. Careful not to stretch it horizontally, just push down vertically enough to flatten it, not indent it with your fingerprints! ( See photo below)

X-axis motor carriage bend

after blow drying and flattening

X axis Test

Problem: The x axis cog which is attached to the motor axle is slipping off the axle.  This is also caused by excessive friction due to the belt rubbing against the washers at the ends

Solution: I used a dremel drill to notch the motor axle (pictures below). Then I used loctite glue to glue the gear cog to the motor axle.  To fix the rubbing against the washers, I reduced the number of washers from above the bearings so that the belt would rub directly ontop of the bearings instead of on the washers.  I also adjusted the height of the belt by lowering it where it attached to the x axis hot-tip carriage

notching the x-motor axle -prep for glueing

After some slices all around the axle

glued on x-motor cog

adjust x-axis belt height

After removing 1 washer from above bearing

Z and Y axis Test

Z axis problem:  The Belt started to slip off the cog You can see me fixing the belt before it slips off.

Z axis solution: I put the cog upside down so the larger part is facing downwards, something like this:
I also put some loctite glue on it just to make sure it doesn’t slip

Y axis Problem: The y axis was only traveling in one direction

Y axis solution: The optoend wires were not crimped fully so it was missing the ability to go forwards and backwards.  You need the optoend connected in order to have the motor go forward and backward.

Initial Ooz test

A video of me testing the extruder along with the hot-tip. I’ve had to adjust the extruder a few times now because it looses hold of the filament somtimes.  I think that is because I don’t have springs pushing onto the filament from the other side of the hobbed bolt.

Ooz test