In another IMHO thread, aceplace57 was looking to make dividers for an equipment bag. Various materials had been suggested including rigid insulation, foam core art board, cardboard and Masonite. I suggested Coroplast - aka corrugated plastic.
You’ve seen it if you’ve seen the bins the US Postal Service uses. The material is available in different thicknesses from 2mm to 10mm, with the 4mm version being the most common. It’s also frequently used to back signs.
It’s two sheets of plastic separated with ribs spaced at the same distance - 4mm Coroplast has ribs every 4mm. There are tools available to easily cut either one sheet or both, guided by the ribs, so you can easily cut and curve the large sheets into a curved surface perpendicular to the “grain” of the ribs.
It’s not a lot harder to cut than cardboard, just using a utility knife, but unlike cardboard, it’s rigid and won’t shed fibers. People are actually making fold-up boats with this stuff!
Bends across the grain can be made withthe roller tool used to insert the the rubber “spline” that holds screen in place. More permanent bends can be made by heating the material. A heat gun can be used to made smooth curves, and sharp bends can be made with a long strip heater and a jig,as seen in this video of someone making a camp food box.
The hardest part seems to be gluing it together, but a boat builder has experimented with a number of different adhesives with success.
I learned about this material when a friend made mea bag for my camera. The exterior is made from “ballistic nylon”, the interior is lined with pigskin suede but the basic case is made from Coroplast. After 10 years of constant use, the case is still holding up.
Anyway, thought it would be a good idea to share this, and hope it proves useful.
Oh yeah, it’s great stuff. Our school prints billboards for the school fair every year on the stuff, though I didn’t know what it was called. I souvenired one one year and chopped it up for a giant dice, which has survived abuse at multiple pre-teen birthday parties in the years since.
It’s functionally basically a way sturdier corrugated cardboard.
I’d never heard of this stuff until my daughter got a fancy guinea pig cage, which uses coroplast for the low walls and the floor. It was interesting to cut and form, it has I would say a unique feel…I can indeed imagine it’s useful for a lot of different things.
The actual material is polypropylene. There are double-sided tapes that work with polypropylene, like the 3M VHB tape.
I myself used it recently for making an enclosure for my 3D printer. The leftover coroplast was useful for making signs for political marches/protests.
Home Depot sells big (8’x4’?) sheets of it, by the way.
Our guinea pigs have it for their floor as well. Though in their case it was leftover election signs from a local pollie, cut to fit. It has lasted almost 10 years so far and is in better shape than the wooden hutch itself. And very easy to clean.
How much weight can this stuff take? E.g., if you walk on it will there be footprints left in it? If you drop something (somewhat lighter than a bowling ball?) on it will it be left dentless?
I run a water stop for the marathon. As of this year we’re using it as the divider when we stack cups 3 layers high. Works much, much better than the cardboard we used to use as it doesn’t loose it’s integrity when there’s a spill & it gets wet.
It’ll get dented up if you walk on it. If you want to experiment with it, you’ll find endless samples along the roadway and attached to poles from people who put up signs like “We Buy Houses”, “Lose Weight Now”, and many others. Often during political season you’ll see much larger 4’x8’ sheets, which are thicker and more durable than the smaller signs seen more often.
Although these signs are often illegally placed along shoulders and right of way, it’s also illegal for you to pull them if you haven’t been authorized by your city. Use appropriate caution as necessary.
A friend had a project where he needed to add dividers to cheap plastic drawer units. He had a low budget for this but wanted something sturdier than oak tag.
We shopped Lowes and bought enough corrugated plastic to do the job easily. It was very cheap, cuts easy and hot glue works find for applying to plastic drawers.
I’ve been watching videos. Learning how to work with this material.
It’s certainly more durable than foam board.
I’m reconsidering my original plan to cover the dividers in fabric. I thought fabric would protect the foam board. That’s not a concern with Coroplast.
If I were doing your project, I’d be sandwiching two pieces together, one oriented side to side, one oriented up and down. That should make the dividers nearly indestructable. I haven’t seen it in videos but you can melt the rough ends to smooth it out (have really good ventilation.) Hot glue looks to be the best thing for bonding joints and seams, and the glue is cheap enough - maybe a bead along the top of each divider to smooth them out.
