reusing old PCB as structural material? - Page 1
Forum section: electronics / general

author: coppercone2
author_rank: Super Contributor
timestamp: August 01, 2023, 10:06:00 pm
content: So PCB boards are often useless after some parts are scavenged. But I realized something, if you take a board, remove all the parts (easy with mostly SMD boards, or just chisel off all components), you could squeegee it with a epoxy putty to fill in any holes and you have a fairly durable fiberglass panel.Do you think its a suitable material for roofing or something? The main obstacle for use is typically the holes, but you can fill those in pretty easy and spray paint it.The only thing their not suitable for is electrical chassis, because they have conductors and thus poor isolation.

author: ftg
author_rank: Frequent Contributor
timestamp: August 02, 2023, 07:50:09 am
content: Roofing? No.For mechanical things inside an enclosure or quick jigs? Sure, absolutely.

author: Psi
author_rank: Super Contributor
timestamp: August 02, 2023, 08:28:27 am
content: I mean, if it was all I had and I had enough of it, sure I'd make a roof out of it.Better than no roof.But, how shall I put this.... FR4 is not known for it's roofing propertiesI think the weight is probably the worst thing about it for roofing. FR4 PCBs are damn heavy when you have a lot of them.And the holes would obviously need to be filled with something.

author: macboy
author_rank: Super Contributor
timestamp: December 24, 2023, 06:05:50 pm
content: I have used FR4 as a mechanical material in the past, but not old PCBs. I had extras of old unused blank copper clad with heavily tarnished copper. Copper is relatively easily peeled off with help of a butane pencil torch and pliers. The peeled copper can be kept for use as a shielding or trace repair, or thrown in the recycling.I would never use a drilled PCB, it will lose some strength, even if the holes are filled. Remember, it's the high tensile strength fiberglass that gives the board strength, the epoxy is just a binder. I would also never use one with copper on it, copper is heavy but weak (add 2% beryllium to it though, and it is as strong as steel!). The FR4 substrate is a surprisingly strong and light composite material, and should have much better strength/weight than common plastics like ABS or acrylic.

author: coppercone2
author_rank: Super Contributor
timestamp: December 24, 2023, 06:10:49 pm
content: hmmm I was thinking about it probobly not a good idea because if the copper corrodes you could have a guilotine fall off your roof. Well IDK, they make roof out of copper but its not gluedbut aluminum.how about floor tiles? you can glue them together to get it to 1/4 inch thick. Maybe like a paver.

author: mendip_discovery
author_rank: Super Contributor
timestamp: December 24, 2023, 08:02:33 pm
content: I remember watching a video of someone sticking coins to the floor then pouring clear resin over the top. Given enough boards you could cover a floor and then clear resin that. You would only need to invite the TEA group over and they will clean your floor so they can get to look at the boards.

author: CJay
author_rank: Super Contributor
timestamp: December 24, 2023, 08:04:02 pm
content: Quote from: coppercone2 on August 01, 2023, 10:06:00 pmFriend of mine removes components with a heat gun and then sands off the solder resist, sometimes the tracks too, to salvage paxolin and fibreglass to make stuff from (new electronics projects, enclosures, tag boards, all sorts, he's real old school, from the valve era and he wastes nothing.

author: coppercone2
author_rank: Super Contributor
timestamp: December 24, 2023, 08:49:19 pm
content: ok if you can handle the dust correctly because it probobly not too good for you.IMO hard to contain grinded boards. otherwise the amount of pollution you make its not worth itthe best recycling processes use minimum processing and generate minimum dust IMO. grinder lung is no joke :'(

author: Mechatrommer
author_rank: Super Contributor
timestamp: December 25, 2023, 01:49:06 am
content: Quote from: coppercone2 on December 24, 2023, 08:49:19 pmyou complaint too much. dont you know how to make flat panel out of raw fiber glass? probably cheaper and safer than recycling technology you intend to do hereurrgh... make roofing out of pcb! you are a joke

author: tggzzz
author_rank: Super Contributor
timestamp: December 25, 2023, 09:11:05 am
content: Quote from: coppercone2 on August 01, 2023, 10:06:00 pmThat would mean metal is not suitable for an electrical chassis, because it is a conductor. Of course, that conductivity is so useful that plastic cases are sometimes spray painted with metal!Here's an example of PCB being used as a chassis/enclosure:Other examples near the bottom ofhttps://entertaininghacks.wordpress.com/2020/07/22/prototyping-circuits-easy-cheap-fast-reliable-techniques