- There is a joy in making your own products, I think that you realize this well. Keep in mind that there is a tendency that people will value and keep the things they make themselves longer thus making it more sustainable.
- Its a recreation with other people (making it with your dad or brother, etc). The furniture becomes a heirloom quality not only because of its design/quality, but the fact that it holds special memory (more appreciated)
- obviously, its an upcycled design that not only reduces waste but also prevents new materials being exploited for new products.
- The level of comfort
- Attachment of each pieces will not only be labor intensive, but also uses huge amount of adhesives and process (keep in mind, that you need to clamp glued pieces together and clean the excess)
- Complexity in making it. Can an unexperienced users create a functional, safe, and comfortable furniture.
I see that you already develop 3 basic shapes, however what are the reasons for these shapes? (are they generated because it offers the most efficient and structurally sound solution for a load bearing product such as furniture). Though you are inspired by lego, you dont have to be conformed with the typical uniformity of the pieces. I recently build a lego tecnic together with my brother and they contain quite distinctive shapes that allow more effective form (check online). They contain gears, cables, hinges, connector pieces, rotationg pieces, cap pieces, structural pieces, etc.
Scrap pieces comes in various types and sizes, how do you ensure that they are cut efficiently into the desired size/shape. Creating jigs that are quite universal (can be used with various sizes of materials) is one way. Are you only using solid wood scraps in strip forms? What about sheet good scraps? Maybe it is easy to manufacture uniform pieces using CNC?
If you intend this furniture to be made by users, you have to provide good instructions/manuals that can be easily followed. If only you can make, this makes the furniture only as works of art, which is something you want to avoid (as you mentioned in the background story, this is somehting you found in the gallery/museum, its more 'fine-arts' than a thesis of 'product design').
Define the kind of furniture you can make with this process. It is understandable not to be able to make all type of furniture. But it's not okay not to know what come out of these blocks and wether they are functional/comfortable/beautiful. Either you make more parts and take picture of the various furniture you can make or use solidworks.
For material source, you may have heard of Build it Green in long island city. Its a NFP that sells collected scrap pieces. You can get your material there. But as expected there is never a consistent amount and type of materials you can get there. A couple of months ago I interviewed some designers from UHURU and they get their scrap pieces from local woodshops. They have plastic piles that they distribute to their 'partner' and collect them once its full. As traditional woodshop makes pretty much the same kind of furniture, you can expect similar kind of scraps everytime and in consistant amount. Though this may not be an inventive way of obtaining scrap, there's nothing wrong of wanting to do the same thing. Also depends on the type of 'wood based material' you want, you can also look at various demolition projects, and see what kind of scraps they get from stripping a building/house, striping kitchen cabinets (maybe you can partner with demolition companies).