What is wrong with my tower?

sr243
Member
Member
Posts: 138
Joined: January 15th, 2008, 4:53 pm
Division: C
State: WI
Location: WI

What is wrong with my tower?

Post by sr243 » March 13th, 2011, 9:08 am

This is my tower design, it weighs 8.7 g but it failed because it was slanted slightly, and the sand was on that side. Also, the glue was kinda old and was not holding up. I was wondering how much would the design hold if there was no construction flaw?
http://img153.imageshack.us/i/0312110102.jpg/

User avatar
eta150
Member
Member
Posts: 269
Joined: March 11th, 2009, 3:48 pm
Division: Grad
State: PA
Location: Kville

Re: What is wrong with my tower?

Post by eta150 » March 13th, 2011, 9:55 am

First of all, the reasons for failure were the ones you just describe. Slanting and old glue. Contrary to popular belief, though, the sand's position in the bucket does not matter, as it will always be the center of gravity and pull straight down on the tower. If you can fix the slanting, you should be able to hold most of the load with that design. It would be a lot easier to know what the problem is, though, if you told us how much the tower held.
#ACESWILD

User avatar
Littleboy
Member
Member
Posts: 373
Joined: March 14th, 2010, 4:53 pm
Division: C
State: MI
Location: Between the Earth's Core and Mars.

Re: What is wrong with my tower?

Post by Littleboy » March 13th, 2011, 10:07 am

Also, can you put a picture in the image gallery?

sr243
Member
Member
Posts: 138
Joined: January 15th, 2008, 4:53 pm
Division: C
State: WI
Location: WI

Re: What is wrong with my tower?

Post by sr243 » March 13th, 2011, 4:40 pm

It held 3.6 kg, the slanted part broke. I know it can easily hold 10kg because that was a design I used a couple years ago. I tried to post a picture in the image gallery but it hasn't been posted yet. I know that the position of the sand doesn't affect the bucket, but I was wondering if swaying the bucket to one side will.

hogger
Member
Member
Posts: 187
Joined: July 12th, 2006, 7:07 am

Re: What is wrong with my tower?

Post by hogger » March 14th, 2011, 6:52 am

If you think that the slanting is the problem, you probably want to build it without slant next time. Same goes for the glue. I can't tell much from the picture exactly what is wrong, but you may want to build it such that the top portion is slanting inward towards the middle a little bit on all 4 posts. That should help with stability.

sr243
Member
Member
Posts: 138
Joined: January 15th, 2008, 4:53 pm
Division: C
State: WI
Location: WI

Re: What is wrong with my tower?

Post by sr243 » March 14th, 2011, 6:53 pm

I think I am going to try a rectangular base to prevent slanting. It should use about the same amount of wood, but any precautions before I do?

User avatar
eta150
Member
Member
Posts: 269
Joined: March 11th, 2009, 3:48 pm
Division: Grad
State: PA
Location: Kville

Re: What is wrong with my tower?

Post by eta150 » March 14th, 2011, 7:04 pm

sr243 wrote:I think I am going to try a rectangular base to prevent slanting. It should use about the same amount of wood, but any precautions before I do?
A square base is much more resistant to tipping over, and with a jig, it can be just as easy to align.
#ACESWILD

sr243
Member
Member
Posts: 138
Joined: January 15th, 2008, 4:53 pm
Division: C
State: WI
Location: WI

Re: What is wrong with my tower?

Post by sr243 » March 14th, 2011, 7:52 pm

Just wondering how is a square base more resistant to tipping over? I don't have a jig or materials/time to make one. For squares, I have trouble making it all even and perfect sides because the sides tilt inwards.

hogger
Member
Member
Posts: 187
Joined: July 12th, 2006, 7:07 am

Re: What is wrong with my tower?

Post by hogger » March 15th, 2011, 7:40 am

sr243 wrote:Just wondering how is a square base more resistant to tipping over? I don't have a jig or materials/time to make one. For squares, I have trouble making it all even and perfect sides because the sides tilt inwards.
Square base has larger area at the base and symmetrical on the two perpendicular direction, while rectangular base is wide on one dimension and much thinner on the other dimension at the base. The thin side is more susceptible to tipping because any slight slanting or leaning error on the thin direction is greater in proportion to the displacement of the base than it would have been if the base was not that thin. Imagine if you were standing straight with feet closed together and got pushed from the side versus you crouch down a little bit with feet apart to the side, which arrangement is harder to be pushed over? To combat that, you try not to build straight up on the thin side, you need to spread the base apart a little bit and lean the 2 sides in such a way that the tower gets slightly smaller and smaller towards the top. Also try to be as symmetrical as you can which means a jig in the middle to clearly align the two sides is probably a good idea.

This video should help with jig for square base:
http://www.youtube.com/watch?v=KOpP7cLvcdk

sr243
Member
Member
Posts: 138
Joined: January 15th, 2008, 4:53 pm
Division: C
State: WI
Location: WI

Re: What is wrong with my tower?

Post by sr243 » March 15th, 2011, 3:07 pm

thanks for clearing things up, I think i know what to do now. I am going to still try a rectangular base but if it isn't as good, I will return to the standard square base.

Locked

Return to “Towers B/C”

Who is online

Users browsing this forum: No registered users and 1 guest