Estes EAC VIPER #0820, BT-55 Upscale, Part 8, Heavy Duty Engine Mount HD-EM

I needed a 20/55 engine mount and went with my Odd'l Rockets Heavy Duty Engine Mount. (Of course, I did!)

The construction of the mount is a little different than a standard engine mount.

The body tube is a Odd'l Heavy Wall BT-20.

The Engine Hook is Spring Steel, 3" long. You'll see why it is 1/4" longer coming up.

The centering rings are custom cut, from black Letramax, stronger than standard white card stock.

The Kevlar is 135 lb. strength.

First, the Kevlar line is tied tight around the BT-20H tube and removed.

A notch is cut in the upper end of the tube and the engine hook slipped in.

A centering ring is slipped over on each side. Look at the first picture to see the slight difference between the two.

The wider engine hook slot (allows hook movement) goes to the bottom.

On the other side, the plastic guide tube slides into the two round holes. You might have to enlarge the round holes a bit.

A wrap of electrical tape goes completely around the tube holding down the hook and small tube.

Glue fillets are applied on both sides of the centering rings.

Note the engine block goes under the top bend of the engine hook. That's why the the hook is 3" long. It's a more stable and stronger mount. The upper end of the hook can't move at ejection or tear down the body tube.

Slide the engine block ring in from the bottom, dry - no glue yet. Push it in place using an engine casing. When the block hits the top bend of the hook, the bottom of the casing locks under the low bend of the hook.