Jump to content
HybridZ

Potato Gun


Challenger

Recommended Posts

Hey I recently made myself a new potato gun and Im just needing to do the ignition system now. Ive used a barbeque ignitor a flash unit off a camera and they all worked for a while to make a ok spark and then broke. Im not a electrician and I was wondering If anyone had a good Idea on how to get a good consistent spark for pretty cheap.

 

Ive been looking at tasers on ebay but there kinda spendy.

Link to comment
Share on other sites

  • Administrators

Here is your source for spud gun tech.

 

http://www.spudtech.com/

 

Some guys are using Tazers which are expensive an supposedly offer less misfires, (HOT ignition source). I have had good luck using the BBQ lighters, but mounting the button in such a way as it is protected helps. I have only had one BBQ igniter ever fail in well over 1,000 plus shots. I have since quit making combustion spud guns due to inconsistency and misfires, the sticky gooey mess, etc. I now only build and shoot pneumatic starch launching devices as they are consistent, reliable and NEVER misfire. Also, the pneumatic launchers are between 2 and 4 times more powerful than the combustion spud guns, (i.e. hair spray/ether ignition source launchers). I build them with interchangeable barrels, i.e. Paint ball, 50 caliber, 75 caliber, 100 caliber, 125 caliber, 150 caliber, 200 caliber and 250 caliber Paint balls are my favorite, though apples, potatoes, etc are also fun in the 125-200 calibers. For my paint ball barrels. With the gun tuned down to shoot at 300 FPS across the chronograph, (full power is 800+ FPS paint balls) the gun is mouse fart quiet and fairly accurate. 12” pattern out to 30 yards. Anything over 400 FPS and accuracy diminishes terribly as the round paint balls flight path tend to spiral and hook.

 

 

Here are a couple shots of my small rifle style Pneumatic launchers with dot sites, one is also wearing a home made laser site.

 

AssaultTater1.jpg

1.jpg

 

 

2Medium.jpg

Link to comment
Share on other sites

Yeah I looked at that website. Im hoping to get a taser off ebay but if that fails I was wondering if any of the electricians on HybridZ would know how to make something to make a good spark.

 

My guns pretty simple 5'' chamber down to 2'' by 4' barrel that is detachable. Also has a airvalve in the plug so you can "supercharge" it. There not that unreliable if you get the mixture right. Ive never used airspray, carb cleaner works alot better.

Link to comment
Share on other sites

  • Administrators

Yeah, the key is getting the mixture right, and when it is correct, you know it. A nice crisp BAM!

We were working on a Propane injection version, utilizing a Datsun cold start injector fired with a 555 timer for introducing the proper amount of propane each and every time, and also utilizing some form of Multiple Spark arrangement using an automotive ignition coil. I gathered all the parts, started the wiring, then came across pneumatic launchers. Built my first one and never looked back to combustion since. Been building and playing with pneumatic launchers of varying degrees of power and capabilities now for close to 10 years.

 

 

Here are some mechanical propane injection spud guns…

http://www.advancedspuds.com/propane.htm

 

http://www.burntlatke.com/lp.html

 

http://www.advancedspuds.com/ghetto.htm

 

 

 

General spud gun links..

http://www.advancedspuds.com/index.html

 

http://users.frii.com/bsimon/backyard.html

 

http://www.spudfiles.com/

 

 

Latest launcher is an all PVC bolt action 4 shot magazine, (5 if you preload the chamber) paint ball sniper rifle with a cheapo Bushnell fixed power 4x32 scope, parallax set at 30 yards, barrel is fully moderated, (silenced). Spent the better part of 20 hours machining just the bolt action. During the proof of concept phase after shooting approx 200 shots through it, (and it was working beautifully, ready for the trigger timer and final battery mounting etc) I dropped it on the ground and the gun broke at the action, DOH!!!! I plan to build another one, probably not till next winter though.

 

Here some pics.

 

Bolt action during fabrication, broken gun fully assembled.

 

BoltMedium.jpg

 

Complex2Medium.jpg

 

ActionMedium.jpg

 

Boltaction1Medium.jpg

Link to comment
Share on other sites

Wow, thats some good machining. Im going for the simpler style gun.

 

My barrels detachable so I wont have to ram the potato down which takes awhile. I can just unscrew the barrel stick it in and screw it back together and Im good to go. I wouldve made a pneumatic gun but I dont have a compressor.

 

 

Cheap latern starters always work best for me... nearly never misfires like the elec grill starters do...uses zippo flint... found at anywhere that sells camping stuff...aka Walmark...

 

If I dont get the taser Ill consider a flint one.

 

Right now it doesnt have any kind of handles or trigger but Ill probably make something once I get the ignition system. Then itll look like a gun rather then a really tall piece of PVC.

 

OTM, I bet that marshmellow gun shoots really far.lol

Link to comment
Share on other sites

Well, I use a grill igniter on mine and haven't had any problems. I actually stuck the igniter inside the chamber, but I've seen people put bolts through the sides and wire it up (like you would your taser).

 

I'm surprised the camera wasn't enough zap for you. If you get a 2nd or even third camera as donors you can piggy back the capacitors in parallel. Not series- you want them in parallel. It will take longer to charge if you do this. And, if your solder joints aren't good they'll blow apart after a few discharges (that's the voice of experience). Disclaimer... I'm an EE but I do digital stuff!

Link to comment
Share on other sites

Several years ago i nearly complete a spud rifle, with a stock i whittled myself. It was made with a 1/2" copper pipe barrel, and 1 1/4" chamber. I used a barbeque lighter for the ignition source. One wire was grounded on the copper chamber, and the other went to a home made "sparkplug" made of copper wire, gaped just enough for the inside surface of the copper chamber that a spark would arc across when you pull the trigger.

 

To load it, i took a filler valve from a lighter and mounted it on the chamber, so that fueling it up was just a matter of pressing an aerosol can of butane on the valve for a second or too.

 

I never finished mounting thw trigger, and never got the spark plug to work consistently. I was prolly about 13 when i made it.

Link to comment
Share on other sites

A friend used a BBQ lighter attached using two screws that were close enough to create an arc.

 

Well, I use a grill igniter on mine and haven't had any problems. I actually stuck the igniter inside the chamber, but I've seen people put bolts through the sides and wire it up (like you would your taser).

 

Yeah thats how my first one was. I just didnt like the barbq ignitor cause it wasnt really reliable for me. I actually found a taser for 10 bucks on ebay.

 

The camera flash provided plenty of power the first few times but then wouldnt work any better then a spark off a 9v battery. The first time I tried (sparking the flash unit) it I didnt know how powerful it was and did it in my living room and it made a huge spark and was super loud.

Link to comment
Share on other sites

Well I won the auction for a small 150000 V tazer. It was 13 bucks shipped so hopefully itll work good.

 

Once I get it ill put some kind of screw or bolts into the chamber to make the spark. Ill need to wire from the tazers prongs to the 2 bolts. Anybody have an idea on how to make the electricity arc at the bolts rather then where the wires hook up to the prongs?

Link to comment
Share on other sites

Braaap... of course I have to be looking at this post as my 15 year old son walks by and sees your bolt-action photos...

 

you bassssss-tard!

 

LOL

 

Looks like now I will be machining a bolt-action....

 

Why do I even venture off the car-related section when The Boy is still lurking about? When will I learn?

 

LOL

Link to comment
Share on other sites

I made my first potato gun when I was 14 and and Id shoot at the school across the street (about 175 yd) and my dad would always tell me to put it away and I wouldnt be able to shoot it for a week or so.

 

Im sure your son will be very happy when hes shooting his bolt action potato gun. :)

Link to comment
Share on other sites

The one I last made had a metering tube to measure the MAPP gas that was used to fuel it.

By using a regulator, 2 ball valves, and a length of pipe between the valves, you could regulate the fuel charge against the known volume of air in the chamber.

 

This was a 1.5" barrel, and the friends who's house I left it at figured out that grade AA eggs will often fit nicely in it's barrel. :) We had a few complaints from boaters out in the Puget Sound, saying that someone was shooting golf balls at them..

 

I don't remember where the calculator is located, but there are a few sites out there that have automated the math, and related it to the appropriate sizes of plumbing.

Link to comment
Share on other sites

quick question.. what the heck you guys using for ammo (other than spuds) in a 2" barrel? i've been having to find stuff and put ALOT of tape around it to make a tight fit..

my gun is a 3" chamber around 2' long and a 2" barrel that is like 3' long.. hellacious long gun.. has handles and a laser pointer mounted on top.. pretty accurate.

Link to comment
Share on other sites

Ive just stuck to the potatos. But Im sure you can shoot anything thatll fit snug in the barrel.

 

I wish they made PVC that had a 1.5 inch inside dimension rather then outside so you could shoot golfballs.

 

I get my taser in the next few days!!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...