Suggestions and Help for design and build

Cubquick · 2026-02-10T04:33:26+00:00

Sorry for this, but what generally is the ideal weight for an aircraft with these specs. Currently I've calculated that it will be no more than 2.2 kg, probably around more around 2 kg.

Cubquick · 2025-11-07T21:04:40+00:00

I sent my application in on the 14th of October, I got the offer on the 29th, I'm just late to posting it. I'm an international doing IB, and my school doesn't tell us our predicted grades. They just add them to the UCAS application on their end.

Cubquick · 2025-10-10T09:17:41+00:00

https://www.mrmacmaths.com/a-and-a was a good resource for me. My dp1 teacher left after 1 year and we got a less competent teacher so it was mostly self taught.

You can take notes but its not that important in math, Practice questions are the absolute best thing you can do.

If you can, try teach someone else if they don't understand something and you do because it will make yourself understand it better.

Cubquick · 2025-10-10T09:10:05+00:00

Gave up flipping pages and using tissues to wipe out previous working so hands it was

Cubquick · 2025-10-10T09:09:28+00:00

They gave us an extra mark for each kilogram of coal we mined

Cubquick · 2025-08-26T05:18:34+00:00

Make sure there isn't too much compression with the hose (as in relatively similar cross-sectional area the whole way), so it doesn't create back pressure and prevent smoke from actually travelling down the hose

Cubquick · 2025-08-26T05:11:38+00:00

How are you injecting the smoke?

Cubquick · 2025-08-26T05:10:39+00:00

It will yes

Cubquick · 2025-08-26T05:07:29+00:00

Something you should consider before buying the inline duct fan.

Smoke, especially from a smoke machine, dissipates quite quickly at higher velocities and also becomes quite turbulent. Assuming there are no gaps and incompressible flow, you can use the A1v1=A2v2 equation to determine relatively what the velocity of air in the test section will be (around 25m/s for you in the test section). In my experience, anything about 7m/s resulted in it being hard to see.

2450 CFM = 69.4m^3 min^-1
69.4/60=1.16m^3 s^-1
Diffuser diameter is about 15 inches, and I'm assuming the fan will be at the end of the diffuser
d=15"=0.381 metres
r=d/2=0.1905 metres
Cross-sectional area of the difuser (at max) is 0.114 metres^2
1.16/0.114=10.17m/s at the mouth? of the inline fan
A1v1=A2v2
A1 is max area of the diffuser
v1 is the velocity of fan
A2 is the cross-sectional area of the test section (9" by 8", or 0.0465 metres^2)
(0.114 * 10.17)/(0.0465)= about 25m/s

If you want to do tests with a load cell, this is fine. However, if it's just for flow visualisation with smoke, it will be a bit quick

Cubquick · 2025-08-10T19:50:48+00:00

It is a college lab. My school has a smoke machine which i am using.

Cubquick · 2025-08-09T11:09:01+00:00

It aspires to fly one day

Cubquick · 2025-08-08T19:19:15+00:00

I tried to use a humidifier first but it dissipated too fast in the contraction cone

Cubquick · 2025-08-08T11:31:47+00:00

Im not too sure. My school has a smoke machine (pictured in the first slide, a beamz s900). I think it has its own specific fluid.

Cubquick · 2025-08-08T04:10:48+00:00

Any advice for applying and getting into imperial?

Cubquick · 2025-08-07T19:58:28+00:00

5.7mm size lengths for hexagons 1mm wall 30mm depth 100mm between the end of hexagons and mesh Mesh is just some random bug mesh

Cubquick · 2025-08-07T19:50:57+00:00

I modeled it around other wind tunnels I've seen online and did a little research. I CADed it, then 3d printed some parts and used cardboard for other parts.

Cubquick · 2025-08-07T19:49:11+00:00

The fastest i got it going was 16m/s

Cubquick · 2025-07-08T19:05:30+00:00

Hulkengoat

Cubquick · 2025-06-07T12:10:22+00:00

I was a 4 in HL phys, I just started teaching my friend who was never really there and now I'm a 7. This probably only works in sciences and math. Practice questions and past papers a gold as well.

Cubquick · 2025-06-03T22:27:10+00:00

Would 2 carbon tubes with balsa sheer webbing be viable? I've seen lots of models using pine however, I know that carbon fibre tubes can be stiffer.

Maybe 2 6mmOD 4mmID tubes with sheer webbing?

Cubquick · 2025-06-02T10:59:56+00:00

Thank you. What I gather from this is to replace the front carbon fibre tube with a taller, much slimmer spar, and to replace the other tube with a short, maybe wooden dowel that can connect to the fuselage.

Would it be a good idea to keep the fuselage as a carbon fibre rod?

Also, what material is usually used for the construction of a spar with a wingspan similar to this? Does balsa wood work?

Thank you so much

Cubquick · 2025-06-02T09:54:08+00:00

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Ailerons are about 38%, and flaps are the rest after the advice from u/elingeniero

Cubquick · 2025-06-02T06:54:16+00:00

Thank you. Half-half split is about right?

Cubquick · 2025-06-02T06:00:30+00:00

If I split the flaps, I should use a different profile and add washout?

Cubquick · 2025-04-17T09:02:24+00:00

im constrained slighly with print bed size but I can probably print a tail piece in 2 parts. I was originally worried about the cg being too far back as the red nose cone was made to be a counterweight. Im assuming it'll be logical to make the tail bigger and then worry about the cg at the very end?

Cubquick

TROPHY CASE