You are correct, I did not look closely. There is different stuff in some local stores that isn't the beady stuff, I wrongly assumed this was the same.This is expanded bead foam - white coffee cup foam.
You are correct, I did not look closely. There is different stuff in some local stores that isn't the beady stuff, I wrongly assumed this was the same.This is expanded bead foam - white coffee cup foam.
This is known as Oasis is the UK, has a similar consistency to honeycomb sweets.The movie special effects people use something called "green death foam", which is a typical Hollywood FX nickname.
In the real world, the stuff is also called "floral foam" and it is sold (here in USA) as small blocks of foam for florists to stick flower stems into, to make a small display. They put candy skewers and other things into it, to make an attractive presentation. Most Craft and Hobby stores here sell it, Walmart and many others here.
Find a local flower shop or floral display maker and see if they have it, it is medium green in color, very light, and very rigid. Very fine "grained". Probably not as good for a "real" aircraft structure because it will fracture more easily than the common aircraft foams. Also, podiatrists (foot doctors) use this material to make a mold of your feet, they have you step onto a block of this, and it leaves a perfect impression of your foot, arch, etc.
The "green death" name comes from the fact that when you sand it, it creates a very fine and highly irritating dust, so the Hollywood guys making monsters and movie props and such get covered with that dust and have to be sent through a car wash afterward
So absolutely wear a dust mask, eye protection, etc. But epoxy resins should not melt or soften it, and it will surely work for a non-critical part. They come in smaller blocks, which means you may have to glue a few of them together to make the size you need. But you won't have to buy a huge expensive block either.
It’s also sold under that brand name here too.This is known as Oasis is the UK, has a similar consistency to honeycomb sweets.
It is probably worth a shot. 2 observations:I've managed to located an importer of high density XPS that seems reasonable - they are located only two miles from my factory and are happy to deliver to me - happy days! They have only been there about a year and the only thing they do is import this XPS - the specs seem good for what we want - http://www.thermostruct.com.au/wp-content/uploads/2019/07/ISOMAX-300-XPS-BROCHURE_JUN19.pdf
Cheers Vigilant - I hadn't given additives causing a problem a thought but... - fingers crossed!It is probably worth a shot. 2 observations:
1). 300kpa (44 psi) is better than the typical home center XPS we see (15-25 psi), but it is less than the higher grades oh Highload XPS. But, it might work for your "slice it into thin sheets" idea.
2) Some foams contain additives that result in poor bonding to epoxy. You'll just have to try it out to see.
Good luck!
RSD, I'm not sure what you'll need as a low-cost replacement for thin (e.g 4mm) PVC foams. The 15-20 psi stuff is what is typically used for the thicker single massive cores, and does fine. For the thin sandwich approach you are considering, the PVC cores (e.g Diab Divynicell H80) that are normally used have compressive strengths of 200 psi or more (so, approx 1400 kpa). This may allow for a thinner laminate outer skin that can still survive normal handling/hangar rash.The importer said that the 300kpa (44 psi) is guarenteed for all thicknesses, but the 50mm thick is actually about 450kpa (66 psi I think) - which is probably pretty reasonable?
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Hmm - will have to work on that still... lots to do... not enough hours in the day...RSD, I'm not sure what you'll need as a low-cost replacement for thin (e.g 4mm) PVC foams. The 15-20 psi stuff is what is typically used for the thicker single massive cores, and does fine. For the thin sandwich approach you are considering, the PVC cores (e.g Diab Divynicell H80) that are normally used have compressive strengths of 200 psi or more (so, approx 1400 kpa). This may allow for a thinner laminate outer skin that can still survive normal handling/hangar rash.
Excellent Idea, the billet makes a incredible beer box, easy to shape and sand, holds the epoxy well. Makes a extreme esky that also doubles as a life raft- make sure you have a good seal and proper lid lock mechanism. And ropes on the outside to hold on.Cheers Vigilant - I hadn't given additives causing a problem a thought but... - fingers crossed!
The importer said that the 300kpa (44 psi) is guarenteed for all thicknesses, but the 50mm thick is actually about 450kpa (66 psi I think) - which is probably pretty reasonable?
Have grabbed a pack of 25mm, 40mm and 50mm so far. First project will be to make a lightweight cooler box for the boat.
We got some that way (more than we ever needed or asked for) by telling a company that we could use the “scratch and dent” stuff to teach CAP cadets about composites. I will ask our aerospace education officer who we got it from. Technically, I am the one who got it donated (the joke is that I can get anything donated...which is good given that I work for a nonprofit) but I don’t remember who from.Actually find someone who works in the plant. Ask if the have a defect pile and if you could have some of it.