How to make a doorframe backboard?

Question

I'm looking to make a doorframe backboard by modifying an old pullup bar I have at home as per this website:
https://sicgrips.blogspot.com/2013/11/making-gstring-backboard.html

Following that, I am looking to screw on a hangboard like so to support ~80kg of weight on my doorframe.

What equivalent materials at Bunnings can I buy to make this backboard?

JacobZ · Accepted Answer

Hi @sterope,

A warm welcome to the Bunnings Workshop community, it is fantastic to have you with us.

They've used 3/4-inch plywood, which is 18mm plywood, and 2 x 2 pine for the frame. 2 x 2 pine is known as a batten. Battens are often available in stores, but they are not as common as other framing, so I would substitute this with 70x35 Pine Framing.

I'd suggest using these Zenith 10G x 100mm Countersunk Rib Head External Timber Screws for your frame. Two at each connection.

Lag bolts are known as coach screws in Australia. You can use these to attach the steel locking plate to the frame.

You can then use steel flat bar and hanger bolts with washers and wing nuts to lock your backing board in place.

I hope this helps. Let me know if you need any further assistance.

Jacob