inner carpet tubing!

[kat.]

Hi

My son is starting a Science project in which he wants to make a wind tunnel to test model airplane designs.
We can't find an inner cardboard tube that a carpet is normally rolled around. It needs to be about 2 metres long and have a large diameter. Does anyone know where we could find this? We have already tried some shops and the internet with no luck so far. I would appreciate if you could get back to me with any ideas.

Thanks

[huggybear]

why does it have to be cardboard? can you not use PVC piping?

[kat.]

No, it doesn't have to be cardboard. It could be PVC. He needs to be able to cut out a window so he can watch how the planes fly. Any suggestions on where to go for PVC tubing and how to cut it?

[sundaymorningstaple]

No, it doesn't have to be cardboard. It could be PVC. He needs to be able to cut out a window so he can watch how the planes fly. Any suggestions on where to go for PVC tubing and how to cut it?

There are a number of stockists in Ubi's Ave 1 & 2. Actually, just drive into virtually any industrial estate and you will see stockists of PVC pipe and other hardward. Usually you will spy the racks with Pipe ends facing the store front so you can see from the street what sizes they have.

You can cut PVC Pipe with any kind of saw. If you have a drill just drill a 8mm hole or so in each corner of the square window you want to cut out and then use a jigsaw (if you have one) or a keyhole saw (manual labour!) to cut your window. Might want to also get a bunch of sandpaper to smooth the edges of your cutout as well.

Alternately, you can use a linoleum knife but I don't recommend this avenue at all unless you have experience with them. It a hooked knife shaped in profile something like an eagle's beak. Nasty piece of work especially if trying to work on a curved surface (not designed for it) unless you use clamps and a jig cutting guide.

[kat.]

Thanks for that. Guess what I'm gonna be doing this weekend!

[sundaymorningstaple]

It's now 8 pm Sunday night. How's the wind tunnel coming along?

[bigfilsing]

yeah hows it going.?

Or did you follow SMS's advice and spend most of the weekend in the ER. Linolium knife indeed Hows the kid supposed to do his science project whens he's passing out from blood loss!!!

Whether it's cardboard or PVC you can make a window to watch the planes from a PET bottle. Clear plastic bottle that most softdrinks come in.
Pepsi bottle is the best as it doesn't have all the contours of other bottles.
to mold it into shape get the hair dryer out and you'll find you can alter the shape quite easily.

So now he's bleeding and burnt SMS.

[huggybear]

for a guy who survived 'nam...some minor bleeding and a superficial scratch is not a big deal besides...it's character building.

from a guy from the mean streets of bloomfield hills, MI, if ur using PVC piping...might not be a bad idea just to go to one of the construction sites and pay one of the laborers $10 to just cut the hole for you. that's what we do in the mean streets of bloomfield hills. hahahahaha.

[sundaymorningstaple]

Hey guys, gimme a break. I didn't advise doing it that way. But the Pet bottle won't work as I think the large diameter PVC pipe is meant to be the windtunnel and mounting the paper airplane inside. The Pet bottle would make the idea covering for the hole in the pipe to observe the wind flow over the plane inside the tube. (I gather that's what he's attempting to do). The easiest way was as huggy suggested though. Give the guy at the hardware store and extra Tenner and he would probably cut the square and even cut a piece of clear perspex to use as the viewplate.

Am curious though how he made out. (My son is now almost 18 so don't get to do any projects anymore! )

[kat.]

Thanks for all the interest!!
We took your advice and looked around on Sat afternoon for PVC piping. Bearing in mind we are fairly new to Singapore we struggled a bit, one way streets etc. Finally found a pile of pipes with display floor tiles against them outside a plumbers shop but the shop was closed. I phoned the guy but he couldn't understand me or was busy on call so he asked me to phone back. Think we'll just go back to the shop sometime this week. I was very tempted to just take the pipe cos it was ideal but that's not a very good here, is it? So, luckily my son is on holiday now and we don't need to do the experiment until he goes back to school. Maybe we'll mention you in the acknowledgements! Oh, a coke bottle would not be big enough, needs to be about 30cm diameter. I'll let you know how we get on or feel free to provide any more useful suggestions.
Kat

[bigfilsing]

Whether it's cardboard or PVC you can make a window to watch the planes from a PET bottle.

What part of window do you lot miss?????
I know i'm renown for talkin ^&%@cks most of the time but gimme a break here.

The interesting bit will be when he wants a smoke trail to visulise the air flow

If you get really stuck let me know. I'm sure my lot can organise some PVC pipe for you.
Good luck

[sundaymorningstaple]

Looks like I'm not the only "Old" kid on this block after all! (just the oldest! ) This is the way forums should be!

Small 12" Table fan can provide the airflow(on low speed) and incense/joss sticks to provide the smoke trails? If using ~30cm PVC Pipe a 12" fan should be just perfect. Then just drill a few appropriate sized holes around the circumference of the pipe ahead of the viewing window and just ahead of where the plane would be mounted and insert the joss sticks to the proper depth for flow over the wings and fuselage after lighting them. Eurika! Smoke trails that also freshen up the room as well after exiting the windtunnel.

[kat.]

bigfilsing - would be great if you know where we can get the PVC piping. let me know. I get what you mean about the 'window' now. We were gonna use a piece of clear acetate.

We have already looked for fans. We wanted to look at the effect of air temperature ie. gliders using hot air thermals. The fans we looked at had only speed settings, which is good because we are gonna look at different air speeds. We thought we'd try to use a hairdryer along with the fan to create hotter air.

Like the idea of the incense sticks!!?

[huggybear]

how about a science supply store? maybe they have a large glass tube or something that could work? where do all the chemistry students go to gear up?

[sundaymorningstaple]

I pass one hardware store every day that has PVC pipe out front of the building. I'm not sure where you are currently living but I live out on Yio Chu Kang Road. The Google map overlay below shows were (within the area of the red oval) on Yio Chu Kang. Very near the turnoff to go to Serangoon Garden (where Chomp Chomp and BBQ'd Stingray wings are! yum yum! )

Any street directory will get you in the vicinity. Or if you get off the CTE use AMK Ave 3 and then Right on YCK Road down about 1.5 klicks or so. As I said, you can also go out to Ubi Ave 1 or 2 and also find suppliers/stockists.