ripple tank - construction

vinyl record deck cover

In message , michael newport writes

I've got the opposite problem! How do you salvage the aluminium edging from a shower door?

Tapping vigorously with a mallet and wooden punch has little effect. I have tried heating with a hot air paint stripper, no good.

Next is blowtorch but I'll wait until I am ready to sweep glass off the workshop floor.

Perhaps freecycle could find you someone scrapping a suitable shower surround?

The ripple tanks we had at school were plate glass in a wooden frame and that wasn't that deep either - maybe 6mm

You can construct the tank the same way many glass fish tanks are made from sheets of glass simply glued together with silicone sealant. No need for a ny framework, if you are concerned about sharp edges ask your glass supplie rs to polish the edges. 10mm thickness seems a bit over the top.

Richard

This is not going to work. I tried this some years ago and the weight of the water soon blew the jointing material. I used epoxy.

I don't know how big you want this but surely there has to be makers of large transparent trays around the place? Brian

How big?

What about (several of for strength) the lids from seedling trays?

For extra size cut and lap join with clear packing tape over, it'll be essentially waterproof.

The edges of tape and lids will cast shadows along with the ripples this may or may not be a problem for the OP.

But the use of a lid or similar has sown the seed of clear plastic containers that shop baked goods come in. Might not be large enough from a "big five" supermarket but CostCo sell packs of 30 mini danish's in a box about 12 x 15". It would need some supoprt but a simple frame around the outside onto the flange might suffice.

Also, you can remove sharp edges yourself easily enough using emery paper. (I just cleaned up a chip on a pyrex jug using a small abrasive burr in a Dremel)

You probably want beaches to kill reflections at the sides. Might be easier to ask a local school where you can buy a Nuffield ripple tank. (I couldn't by googling)

Andy

tight?). I'd

From memory (I've been retired from teaching physics for over 8 years), the speed of waves in shallow water is inversely proportional to the depth. You won't want any deeper than 1cm and will need beaches to stop reflections. Perforated zinc and/or detergent can help. Strobe (spinning slotted disc) will aid viewing Which properties are you looking to demonstrate?

That pyrex stuff is tricky; when it breaks you get a bazillion sharp little splinters. My mom would throw any anything that was chipped, in case it did.

When I was teaching we bought supplies from Griffin & George

Malcolm

In message , Lawrence writes

I worked for two years at a ship model experiment tank: basically a very long swimming pool, see the Dam Busters movie.

That had a wave maker consisting of a variable speed DC motor raising and lowering a wedge into the water.

The *beach* was a ramp of what looked like roofing battens fitted across the far end of the tank.

There was a wave maker at the late-lamented swimming pool at Portobello, Edinburgh.

It'll be easy enough to by a ripple tank (we quite often by scientific equipment as we home educate) but a new one won't be very cheap.

But half the fun is putting together your own stuff.

We bodged together a ripple tank from a large shallow rectangular pyrex dish. As others have said you need some sort of 'beach' round the edge.

Following some suggestions on the web, we used some fine-ish wire mesh covered with some cotton gauze to form the sloped sides. (commercial ones just seem to rely on having a sufficient slope, but the idea here is that the mesh and cotton wlll absorb some of it as well.

Whilst it was not perfect - it had moulding on the base that shew up, but it all worked well enough to demonstrate stuff.

Have a play around with what you have, see how it works. I can't see why an aquarium wouldn't work, - just put a shallow amount of water in it.

Next on the list is an air track :-)

Go to a sign maker. They are in most towns. Get some offcuts of perspex (acrylic sheet) - it comes in all colours and clear - and some suitable glue. It's very easy stuff to work.

My recollection (from 50 years ago!) is that half of the interesting stuff came from the reflected waves where they hit the side. I don't think you'd want beach all round.

A large glass baking dish would do nicely, and you can also make apple crumble in it. Nom, nom, nom!

Depends on what you want to show - reflections can also confuse things. Normally they have beaches all round and then you can put in barriers etc. as you wish.

Fair enuf! I'd forgotten, or things were different then.