I made a sled for a MIssileworks RRC3 Sport Altimeter to fit on the "back" side of a Madcow Rocketry Avionics Bay. It fits nicely in between the screw rods leaving the larger flat "front" of the sled free for whatever activities you want. I purchased the Madcow Torrent 4" rocket kit, this should work for any of the madcow 4" kits. I'm not sure what the dimensions run on the 3" kits in terms of the avionics bay, but it might just fit inside of that as well.

The mount slides in between the mounting posts/boards, wraps over the top of it to hold itself in place. Mine held upsidedown without any screws but you definitely would want to screw this in place using the holes already on the model. I was quite pleased with how this turned out. I have some holes in the bottom to allow the air pressure sensor to read the correct altitudes etc. There is a mounting location at the bottom of the sled, with negative space cutout for a washer to help prevent it from breaking from high G forces.

I've successfully flown with this using a Cessaroni H110WH to 1,225' @ 207mph and an I125WH-10 to 2,611' @ 311mph. Both times altimeter was within 20' of Rocksim simulation

I added a photo for the RRC3 LCD Display, but you can see the sled in the background holding the altimeter, i need to find the pictures i took during assembly and i will update it.
Edit: I added Pictures i took along the way, note, this was my first version, the version of the STL i shared has additional holes in the side for the pressure sensor underneath.

I used 4 M3 screws to attach the Altimeter to the sled, and a pair of wood screws with washers to attach to the Avionics bay sled itself. There is a recess for standard 1/4" inner diameter washers, but even if you choose a larger washer, there is enough clearance underneath.

Anycubic

Photon

No

Yes

.05mm layers

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