FlushFit Corner Bracket (No Gaps! No Wobble!)

TLDR: A strong, 3-way bracket for building frames without panel gaps. Perfect for wood, acrylic, or hybrid enclosures.

Note: This model is customizable (parametric), this means you can change its characteristics to fit your needs.

The background
I wanted to build a custom size enclosure for my Bambu Lab A1 to reduce ASA plastic warping and improve layer adhesion. I saw some “fully plastic” versions on Makerworld, but I decided to repurpose some leftover wood I had instead since wood does not suffer from heat deformation.

The problem
I needed a bracket that could connect eight wooden square dowels to form a cuboid frame with acrylic panels.

Most options I found were either:
- Connector joints that let you slide square dowels in at 90 degree angles.
or
- Simple L-brackets that provides very little torsional strength and does not force the dowels at a 90 degree angle.
...neither option met all my needs.
 

As shown, a connector joint leaves a gap between the square dowel and the pannel and makes it hard to insulate and attach the panel.

The solution
A hybrid design:
- The angular strength of connector joints
- The flush design of L-brackets

…

The FlushFit Corner Bracket 
✅ It interconnects three square dowels at right angles.

✅ It provides torsional stability thanks to screws on different axes.

✅ It forces the dowels at a 90 degree angle from eatch other.

✅ It creates a smooth transition between the dowel ends, creating a flush connection.

✅ It enables attaching sheets on the outside with a gap-free seal.

I’ve now assembled the acrylic enclosure, added a motherboard cooling duct and installed a ‘Chitu 3D Printer Mini Heater’ inside. The setup now holds about 50 degrees celcius, so I can finally print ASA! :)

My enclosure

My enclosure uses 3 mm acrylic sheets and withstands 60 degrees celsius without deforming. The square dowels are 21x21x500, 550 and 600mm. The sheet surfaces are:

Sides: 598x609mm
Back: 554x609mm
Top: 548x598mm
Doors: 277x609mm x2

If you're interested in building en enclusure, have a look at my A1 cooling kit:
https://makerworld.com/sv/models/1858551-a1-enclusure-cooling-kit#profileId-1987510