# Mega pumpkin slingshot suggestions?



## Tobin8r (Aug 7, 2019)

Hi there, i am a total rookie building a huge pumpkin chunking sling shot looking for advice.

The colorado pumpkin chunking event is coming up on september 21and 22nd. This is just like the pumpkin chunkin event you saw on discovery channel a few years ago (same guys competing with cannons and 40ft tall trebuchets.

My friend and I are building a ~15 ft tall slingshot to compete in the youth division. (We are juniors in high school)

To test our plan, We built a small scale version that shoots a 1lb lacrosse ball 380 ft with a single 1/2inch thick wall latex tubing from lowes. The two bands were 2.5ft long (each side) and we could only strech to about 5-7 feet before we were concerned about breaking the tubes.

For the large full scale model, we built a 13 foot steel pipe (schedule 80 i think) base and use 2 steel cables on each side to 4 ft steaks to anchor it to the ground. We plan to bundle 10 bands of 3ft slack peices (each side) bundled together and use a 2000lb winch to pull back about 12-15 ft. The pumpkins are 4lbs each. For distance, we should launch approx 45 angle (hence the 13 feet tall)

The organizers of the event are very picky about safety and have reviewed our design on paper.

Is there any advice or suggestions anyone has? I have been trying to figure out best bands and how to bundle properly etc.


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## MakoPat (Mar 12, 2018)

This is way out of my wheel house...buy I am following.


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## flipgun (Nov 14, 2012)

Let me introduce you to Herr Sprave.


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## mattwalt (Jan 5, 2017)

Cool project.

Figuring out how many bands you'll need will be key. Also draw length is more important than draw weight... Also the weight of the pouch side should be kept to a minimum...

You could try using tubes and a pully system to effectively double your draw length - tubes may allow for simple adjustments of band length as well as being able to removing or adding lengths as required...


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## SJAaz (Apr 30, 2019)

Way to go guys! How you going to get the bands pulled back without crushing the pumkin? Maybe some release gimmick on the back of the pouch. Good luck.


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## Blue Raja (Feb 10, 2016)

Tobin8r - welcome to the forum. I am in Elizabeth. I volunteer at the Denver Waldorf School's archery program.

Google "Leach Trench Catapult." The slingshot you built seems similar.

Lots of very knowledgeable people here, so post your questions and your progress.

Good luck with this.


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## Tobin8r (Aug 7, 2019)

Thanks all for the feedback and support. provided I get everything in the mail, I have a friend who has some property where I will try it out this weekend. I will post some pics if anyone is interested...


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## flipgun (Nov 14, 2012)

We are always interested. Good Luck!


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## Blue Raja (Feb 10, 2016)

Please post some pictures. I am sure that everyone here is interested.


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## Tobin8r (Aug 7, 2019)

Well, we have built our first attempt. Here is a quick video of our first attempt:






Need to work on the pouch. Apparently it does not scale up well


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## flipgun (Nov 14, 2012)

Classic failure to match bands to ammo. Take the shrouds off of the bands, get a sphere shaped pumpkin, add a few strings to your pouch and string on some more bands. Better luck next time


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