## Attaching tension to compression/base at correct angles

sciencecat42
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### Attaching tension to compression/base at correct angles

I think the hardest part of boomilever is getting the angle and length of the tension chords correct so that the boomilever will sit on the wall perfectly perpendicular and centered. No matter how many times I measure I can't seem to get it right. How is everyone else approaching this part of the build?

TheChiScientist
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### Re: Attaching tension to compression/base at correct angles

Best way to attack the problem is to have done the calculations for the angle at which the tension cord should be at but also you can use an outline of what your boom should look like to get accurate positioning.
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sciencecat42
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### Re: Attaching tension to compression/base at correct angles

TheChiScientist wrote:Best way to attack the problem is to have done the calculations for the angle at which the tension cord should be at but also you can use an outline of what your boom should look like to get accurate positioning.

So the end of the Jhook is about 4.5cm away from the wall but do you need to account for the width of your base?

TheChiScientist
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### Re: Attaching tension to compression/base at correct angles

sciencecat42 wrote:
TheChiScientist wrote:Best way to attack the problem is to have done the calculations for the angle at which the tension cord should be at but also you can use an outline of what your boom should look like to get accurate positioning.

So the end of the Jhook is about 4.5cm away from the wall but do you need to account for the width of your base?

Not necessarily. It all depends on the design of your boom as you can accommodate bases with a width greater than 2.5cm to a degree.
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sciencecat42
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### Re: Attaching tension to compression/base at correct angles

TheChiScientist wrote:
sciencecat42 wrote:
TheChiScientist wrote:Best way to attack the problem is to have done the calculations for the angle at which the tension cord should be at but also you can use an outline of what your boom should look like to get accurate positioning.

So the end of the Jhook is about 4.5cm away from the wall but do you need to account for the width of your base?

Not necessarily. It all depends on the design of your boom as you can accommodate bases with a width greater than 2.5cm to a degree.

Sorry my question wasn't very clear. We are using a dowel as a base, so I was wondering if we would need to account for the diameter of the dowel when making our calculations for the length and angle of the tension chords.

dholdgreve
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### Re: Attaching tension to compression/base at correct angles

sciencecat42 wrote:
TheChiScientist wrote:Best way to attack the problem is to have done the calculations for the angle at which the tension cord should be at but also you can use an outline of what your boom should look like to get accurate positioning.

So the end of the Jhook is about 4.5cm away from the wall but do you need to account for the width of your base?

Depends... Probably the best way to deal with it is to let the tension rods just run wild. Don't try to cut them exact at first. Now locate the inside face of the hook (the point where your mounting block touches). This doesn't (or at least shouldn't) change, and transfer this to the tension rods with a felt tip pen. Now position your mounting block so it lines up with those marks and glue it in place. Finally, after everything is solid, clip the excess tension rod off.
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