Acrow prop Vive lighthouse mounting system by PhobosIndustries

Last crawled date: 3 years ago

This is a non destructive acrow prop based mounting system for the HTC Vice lighthouses. I wanted a method to quickly set up and take down the lighthouses without having to install fixings in different environments. My design is a remix of the great idea by cmooney91 (https://www.thingiverse.com/thing:1793515). I liked the wedge based quick change system, and wanted to incorporate it into my prop design.
The basic idea is that pressure is applied between the floor and ceiling to hold the fixture in place. The props use a telescopic design, where the excess of the upper stage is kept inside the lower stage. This allows for a use with various ceiling heights. The pipe is just standard PVC electrical conduit, 25mm and 20mm, each cut to a length of 1800mm.
The floor foot (25mm) has a 10mm thick rubber pad screwed to the bottom. The rubber is drilled and tapped to accept M3 machine screws from the top, so that only the rubber makes contact with the floor. Similarly the ceiling foot (20mm) has 10mm thick self adhesive polyethylene foam attached to it to prevent markings. This was picked up at the local hardware store. Each foot has horizontal holes to fit the conduit in place, and these are need to be tapped for M5. The conduit is inserted into each foot and fixed in place with M5 x 10mm machine screws. Anything will work pretty well here, even if you want to screw into the conduit to fix it. Additionally there are holes in the feet for cable ties in case that suits your setup better.
I have made some handles to accept M6 hex head bolts (30mm) so that installing and changing can be done without tools. Each prop uses 4 of these cranks. The design has a thin layer to support the hex slot, and this needs to be drilled out before the bolt can slide through. It was put there to eliminate the need for supports during printing. The inserts are made to fit snugly over the bolt, but I needed to clean up the edges of the hex holes so that they would fit easily.
Next the screwed adjuster needs to be assembled. The large nut has both left and right hand threads to match the 20mm and 25mm parts, so keep the arrow facing up towards the 20mm half. Thread these all the way to the centre. The 20mm side needs to be tapped to accept the M6 bolts with handles, and the 25mm side to accept M5 x 10mm screws. Slide the 25mm conduit into place and tighten. Before inserting the 20mm conduit we need to slide on the lighthouse mount.
The lighthouse mount is held in place with more of the M6 hand cranks, so those holes need to be tapped to M6 as well. Slide the bracket onto the 20mm conduit and then place the whole length into the screwed adjuster. The 20mm conduit fits nicely inside the 25mm.
Now the whole strut can be roughly installed where you need it, tightening the hand cranks to get the 20mm side locked in position. Finally the extra pressure can be applied by turning the centre nut. The holes in the nut are ready for more M6 screws if you need to fix it in place, but haven't needed to do this. I did notice that the more pressure you apply, the bendier the conduits became. It doesn't seem to need much tension to hold it tightly in place though.
The lighthouse puck needs to be fixed to the back of the Vive lighthouse bracket, and for this I have included two versions. The hex model can accept an M5 nyloc nut, the round model fits an M5 socket cap machine screw. I have made the puck a bit deeper compared to the original so the nut or socket cap screw could fit without fouling. This also makes it incompatible with the original design by cmooney91. I used a pair of M5 x 10mm socket cap machine screws.
Finally slide the lighthouse puck and lighthouse into the slot and you're good to go.
I printed this on a Prusa i3 MK2S in white eSun PETG, 0.2mm layer height, 3 walls, 5% infill and no support.
The parts I used per prop:
M3 x 10mm button head machine screw (x4)
M5 x 10mm button head machine screw (x6)
M5 x 10mm socket cap machine screw (x2)
M5 nyloc nut (x2)
M5 washer (x2)
M6 x 30mm hex head bolt (x4)
20mm electrical PVC conduit (1x 4m length)
25mm electrical PVC conduit (1x 4m length)
10mm x 75mm x 75mm polyethylene strip (self adhesive)
10mm x 75mm x 75mm rubber sheet
I have included the source file from Fusion 360 in case anybody wants to change dimensions to suit the materials available to them. If you do make changes I would encourage you to share your design to help others as well.