Ancient Marble Column Pet Door Holder

This is a door holder that props open a Pet door via latches that pivot and are held by magnets. the door can be dropped by just lifting the latches slightly

We wanted a novel aesthetic way to hold the door open. our initial solution was a cardboard tube.

Instructions

Bill of Materials

Choose filament (we chose Sunlu High Speed PLA Marble Shadow Storm Marble)

22 x 4mm rods - I made mine from nails, use what you have.

8x M3 hex nut

8x M3 washers

8x M3 x 25mm Bolts

8x Magnets 8x2mm

2x 10mm Rod 316mm long - I used Wood dowel

4x 8g 20mm wood screws

Superglue

Alternative

Superglue and plastic pins 

or soldering iron

Print

• the 3mf files have the orientation for printing

• or the GCode is already sliced including pauses for magnets and M3 Nuts

• I recommend starting with the Latch. i then used the latch to ensure the Bridge magnets are inserted correctly

Assembly

Start with the Rails.

• insert 4x 40mm pins into the two Mid Rail sections

• press the Left and Right Front rails onto the pins in the Mid Rail. 

• I added superglue between the parts just before finally pressing them together

Next the Bridge base.

• Insert 4x 40mm pins into the Mid Bridge Base

• press the Left and Right Bridge Bases on to the pins of the Mid Bridge Base

• lock in place by adding superglue between the faces

Connect Bridge Base to rails.

• Insert the vertical 27mm pins into the connected Bridge base

• press the Rear and Front rails one at a time onto the pins,

• secure finally once again with superglue

Moving on to the Columns and repeat with the other sided column.

• insert a 10mm rod into the Top Column section, screw in place with a short screw (i pre-drilled then screwed in by hand with screwdriver

• place bridge upside down on the rails. align the 4 holes in the Top column section with the 4 holes in the bridge that contain the captured M3 Nuts.

• insert a washer and a M3 25mm bolt into each of the 4 holes in the Top Column section, adjusting until the bolt passes in to the bridge segment.

• using a 2mm Hex key thread the bolts into the nuts. i get it to be just tight enough to stay in place but i can move it around slightly.

Install the Latches.

• align the Top Column sections just installed with the through hole of the Bridge section.

• insert the latch through the hole. the magnets should snap it into position.

• install the Pivot pins for the Latches (4mm x 40mm rod)

• pressing on the hook section of the latches to test the opening and release to close the latch. move the Top Column section until you can toggle the Latch in and out freely (rotating about the pivot)

• finally tighten down the M3 Bolts

• press the  Pivot Covers into seal the bridge

Complete the Columns.

• sleeve the 10mm rod with the Column and recess it into the Top Column section

• press on the Column Base until the Column recess into the lip

• secure the rod with another small screw through the bottom of the Column Base. the screw should be tight enough to hold the Base in place but allow you to twist slightly to align it parallel with the top and other side (Right with Left) 

Test and Fine tune.

• installed in front of the door you can lift the door into the model until the latches slip open and close around the door holding it in place.

• you can finely adjust the distance between the latches so they catch and drop the door correctly buy warming up the latch with something like a hair dryer, hot air gun etc. (not fire) then bend the PLA hook out into the needed position. switching to cool air is helpful to set it in its place so you can let go sooner

Enjoy