Transferable / Adjustable Firewall Mounting

Transferable / Adjustable Firewall Mounting

Here is a quick and easy way to produce an adjustable and transferable motor mount. To make this mount, you will need -

• One firewall
• ~8" of extreme packing tape
• A piece of sandpaper
• One plastic gift card
• Scissors and/or knife for cutting gift card and trimming tape

This is a technique I have been using for mounting motors to my scratch built foam planes. This method allows for adjustment of thrust angles and movement of motors between airframes. I've mounted motors on planes with 48" and 60" wing spans using DT750 motors on 4S with 11x4.7 props. It has proven to be strong and reliable as well as durable and resilient.

Most of the planes I build use 2" outer diameter square foam tubes for the fuselage. In cases where the fuselage is not a 2" tube, the nose of the plane narrows down to approximately 2". I use 2" as that is the width of a standard FT Firewall. You can easily use this same technique with the 1 1/2" Mighty Mini Firewall or a custom sized firewall of your own construction.

Start by removing any burrs from the edges of the firewall.

The reinforced tape is strong, but a burr can puncture through the tape with the shock created on impact. That could cause the tape to rip.

Next, measure the height of the firewall against the gift card.

Then cut the gift card to the appropriate height.

Cut that piece approximately in half.

Lay out a piece of extreme packing tape. Place the firewall approximately in the center of the tape. You can use more tpae if desired. I have used the tape doubled up and I have used two pieces of tape aligned top to bottom, splitting the the lateral center of the firewall (this gives more tape to fold over at the top and bottom of the firewall).

Align the gift cards at the ends of the firewall, centered top to bottom. Make sure they are standing on end and firmly in the corner. This allows the cards to form the sidewalls after the tape is folded over, without placing extra stress on the card/firewall tape joint.

Trim off the excess tape and fold over the ends and edges.

That gives you a transferable and adjustable firewall.

Clean up the holes covered by the tape and mount your motor.

To use the firewall, set your thrust angles.

Then tape the firewall in place.

Make a quick release tab in one end of the tape.

Finish up by closing up the tape.

Add hot glue as desired to prevent lateral drift.

It helps to finish your fuselage with some sort of tape covering. This will allow the extreme packing tape securing the firewall to be peeled off the plane without damaging the paper.

Here is a relatively short video describing the process.

I hope that you find this helpfull. If you use this technique, plese share your results on the forums and show us your planes.