Towers B/C

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Re: Towers B/C

Post by retired1 » April 26th, 2018, 4:11 pm

waffletree wrote:
MadCow2357 wrote:
waffletree wrote: Helps you cut the balsa sheets into the size you want. It also depends on what you are using to cut your wood right now. If your cuts are nice and straight, you don't really need a balsa stripper until the quality of your cuts are becoming a problem. I prefer buying wood that is already cut (from specialized balsa), so I don't use balsa strippers.
I cut with a razor. Do you use 1/16" by 1/32", or 1/16" by 1/16"?
I use 1/16 x 1/16 but I've also used 1/16 x 1/32.
If you use a razor, you should be fine if the cuts are straight (like I said before).
Look into a master airscrew stripper. As strippers go, they are very cheap and quite effective on balsa up to about 1/16" or 3/32".

Whether you use this or a metal ruler and razor blade, You will find that you will get much more even strips if you use 18" pieces vs the normal 2' or 3'. For towers you will get as much usable strips this way (less scraps).

I would be prone to use extremely careful selection of store bought wood for the legs as a very small non uniformity can make a huge difference in what it will hold.

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Re: Towers B/C

Post by MadCow2357 » April 27th, 2018, 10:51 am

Balsa Man wrote: The leg pieces go along the outer edges of the panels/plates. They are oriented so that, looking down at the end of a stick, one of the diagonal cross section lines is pointing to the vertical centerline of the tower – the center of the jig where the panels cross. To describe it another way, the ends of the sticks are square; if, looking at an end, you rotate the stick 45 degrees, they have a diamond cross section. You want them oriented so that one ‘point’ of the diamond is against the panels. That way, when you look at the 4 sides of the tower each pair of adjacent legs will flat faces in the same plane. The bracing goes on those flat faces.

As discussed before, you need some sort of ‘leg holder’ pieces, glued onto the edges of the jig plates, to hold the leg pieces in the orientation described above. The two options are small 90 degree angle iron – Hobbytown has small angle iron in both metal (brass) and plastic, and there are other on-line sources, or (the better option if you have 3-d printing access) you can 3-d print pieces. We’re using pieces printed at a 5cm length. When you look at one of these pieces end-on, the width is the thickness of your jig plates, there is a 90 degree “V” notch in the top (which is what the sticks ride in)- the shape is like a capital “M”. The flat side; the bottom side of the "M", is glued on the outside edges of the jig plates.
I will be building one of these jigs, as I am switching from rectangular base to square for nats. But, I still don't entirely understand the edge strips. If I 3d print edge strips, should I design the 90 degree parts, and then make panels on the side to "rail ride" the 3/16 acrylic?

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Re: Towers B/C

Post by MadCow2357 » April 27th, 2018, 12:49 pm

Hey guys, there are Scioly.org t-shirts for sale! There were new logo shirts as well as old logo shirts, but the new logo shirts are out of stock. Bernard says that they will only order new logo t-shirts if enough people want them, so I am trying to convince more people to buy the new logo shirts (I want one). You can have your username be printed on the back of the new logo shirts as well. 8-)
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Re: Towers B/C

Post by PM2017 » April 27th, 2018, 12:55 pm

MadCow2357 wrote:Hey guys, there are Scioly.org t-shirts for sale! There were new logo shirts as well as old logo shirts, but the new logo shirts are out of stock. Bernard says that they will only order new logo t-shirts if enough people want them, so I am trying to convince more people to buy the new logo shirts (I want one). You can have your username be printed on the back of the new logo shirts as well. 8-)
Wrong forums, mate.
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Re: Towers B/C

Post by MadCow2357 » April 27th, 2018, 1:06 pm

Sorry... :oops:
Where should I post this then? I didn't want to randomly post in a forum that I have not posted in before. I thought that it would be better to just post in a forum where I am active in, like this one.
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Re: Towers B/C

Post by PM2017 » April 27th, 2018, 1:59 pm

MadCow2357 wrote:Sorry... :oops:
Where should I post this then? I didn't want to randomly post in a forum that I have not posted in before. I thought that it would be better to just post in a forum where I am active in, like this one.
The thing is, you shouldn't really post this is in any event related forums. Probably make a new topic in the general chat forum.
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Re: Towers B/C

Post by jgrischow1 » April 28th, 2018, 2:36 am

So my kids were kind of ambitious with the number of silica packets they used and they reduced the weight by .24 grams last night. Is this normal or potentially problematic?

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Re: Towers B/C

Post by seadog » April 29th, 2018, 6:22 am

jgrischow1 wrote:So my kids were kind of ambitious with the number of silica packets they used and they reduced the weight by .24 grams last night. Is this normal or potentially problematic?
I have never used silica gel packets to reduce the wight of my tower however the absence of water in the wood may cause the segments to become more brittle and possibly fail earlier. flexibility is important in the segments because it allows the wood to stretch and contract according to the forces applied on it . Hope this helps.

seadog,

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Re: Towers B/C

Post by jgrischow1 » April 29th, 2018, 1:50 pm

seadog wrote:
jgrischow1 wrote:So my kids were kind of ambitious with the number of silica packets they used and they reduced the weight by .24 grams last night. Is this normal or potentially problematic?
I have never used silica gel packets to reduce the wight of my tower however the absence of water in the wood may cause the segments to become more brittle and possibly fail earlier. flexibility is important in the segments because it allows the wood to stretch and contract according to the forces applied on it . Hope this helps.

seadog,
Thanks. .17 grams returned my testing time.

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Re: Towers B/C

Post by cheese » April 30th, 2018, 4:44 pm

I have a question.

When selecting wood for a tower, I usually try to get 4 legs that are about the same density as well as have the same BS. I know that having equal BS is extremely important as the tower will break at the weakest point, and if one leg has a lower BS, there is a very high chance that it will be where my tower breaks.

The thing is, does the density matter if the BS for all the sticks are the same?

e.g. leg 1,2,3 have a density of 108.29 kg/cm^3 and have a BS of 30. Leg 4 has a density of 121.29 kg/cm^3 but also has a BS of 30.

If you use all 4 of those legs, will the uneven weights in the legs cause the tower to break there? Maybe does an uneven weight play a factor?
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