Depends on your seat. I have two set ups. One is an office chair that has fold up arms. I've screwed a metal bar and attached planks of wood cut to size on each arms, and screwed my warthog base to one, and the CH Pro throttle just sits on the other. It cost me about £40 all up, including the chair, which I bought second hand, and the materials from the hardware store.
My other rig uses a Playseat Challenge (I needed a fold up solution), for which I used a couple of
motocycle handlebar mirror mounts that I ordered from Aliexpress. You just need to make sure the mount is the right size for the tubing of the seat.
I then had an angled steal bracket made up to screw the throttle to, and seeing as I use centre mount for the joystick on that seat, I just screwed a block of wood to the to two of the mirror mounts, and then attached my Mongoos T-50 to that block of wood (that specific stick is made to be mounted in such a way).
I find that the best way to do a homebrew setup is to look over various different builds by other people, preferably with well detailed photos, then got to your local hardware store with a concept in mind, then find the parts that will help make it a reality. This does involve a good understanding of the way your stick is constructed, and mounted option.
EG, a Warthog, Virpil or VKB set up will likely allow you to screw things together, though the Virpil T-50 is mounted from the front/back of the body of the base, whereas the VKB, Warthog and WarBRD sticks have a base plate for mounting.
Sticks like a TM T16000M, or CH products don't really have anywhere to mount, so they will just sit on a plate of some description (wood or metal), and you'll likely want to have something to keep them in place, unless you're willing to screw into their base.
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