I have built my own rigid heddle loom, and it works FANTASTICALLY! I have noticed a lot of discussion here and elsewhere on the internet about trying to build more complicated looms than your simple frame loom. I would like to share my plans with whoever is interested in them, because I have drawn up a great set of plans for reproduction of my rigid heddle loom with a low supplies cost of $25, but that is only if you can't find scraps of wood lying around your garage. Take a look at the plans and please let me know what you think! A lot of my fellow weavers have acquired the plans, built the loom, and had great success, while letting me know what I can improve about the plans. If you are trying to build your own rigid heddle loom and need a set of plans, please give these a look and let me know what you think so I can improve the plans!
https://www.etsy.com/listing/602925222/plans-for-building-a-rigid-heddle-loom?ref=shop_home_active_3&crt=1