The tailpipe expander is a cool idea. I'm going to try putting the inner can on a rod with a groove in it, and hammering the thin sheet into the groove, so the circumference will get smaller. 👍
Glad I saw this, I've picked up a few aluminum alloy softball bats that I've wondered about using for an exhaust project for a small engine machine. Thinking the medium pipe expander will be a perfect tool to use to prep for fitment. Also, great excuse to work on the cans I've been saving up. Thinking will be interesting to see the detail regarding like which DIY easily available (packing tape, PETE bottles, wax paper, various thicknesses, etc.) dielectric insulators used and maybe like some less common like the teflon toaster packets or non-stick sheets.
Too smart. Shocked that people don't consider this more for testing and creation of solution. Need to find your video on the resulting mag loop tests with this. - N1KTJ
Same idea as the Gamma match my father built for his stack of two 5-element 2-meter Yagi beams... He used two sizes of tubing, I think one copper and one aluminum (I think the use of two different metals had more to do with local availability more than anything else), with a neoprene or similar tube separating them. Small tube inside the neoprene, neoprene inside the bigger tube. Worked great back then (1995 or thereabouts).
checked current price at Harbor freight. Only 14 dollars for small tail pipe expander or 19 for the large one. It doesnt say what the "exact" size is. So I will just have to visit the store and see. But really, this is a great idea. I live in a HOA controlled area and it is looking like the magnetic antenna(using trombone cap) will be my best option.
Wow, that's nuts the inflation. Now is ~$20 for the medium and ~$32 for the large one. Notes online, "Works with all 1-1/2 in. to 2-1/2 in. mild and aluminized steel pipes" for the medium and "2-1/8 in. to 3-1/2 in." for the large Laguna brand they both are. Was wondering if that meant the pipe size inserted and can expand and if so, what's the amount can expand since doesn't state the pipe thickness and am guessing that standard amount whatever that is.
Great idea with the tailpipe expander. Found you looking for a trombone capacitor. I am thinking it won't be real good for transmit. Probably arc over, but for receive,, very cool.
Yeah, I was wondering what the breakdown voltage is and wondering what different insulator materials performance will do to affect that. Maybe even some lube of some sort might effect, i.e. a teflon or silicone type.
How did the cap perform? Was it stable? Did you have a problem with leakage? Did you measure the ESR? Did it have an inductive component? I really like your idea.
The critically missing piece of info is how to anneal a thin aluminum can. Please add that info; otherwise, following your instructions will probably end in failure.
The tailpipe expander is a cool idea. I'm going to try putting the inner can on a rod with a groove in it, and hammering the thin sheet into the groove, so the circumference will get smaller. 👍
Glad I saw this, I've picked up a few aluminum alloy softball bats that I've wondered about using for an exhaust project for a small engine machine. Thinking the medium pipe expander will be a perfect tool to use to prep for fitment. Also, great excuse to work on the cans I've been saving up. Thinking will be interesting to see the detail regarding like which DIY easily available (packing tape, PETE bottles, wax paper, various thicknesses, etc.) dielectric insulators used and maybe like some less common like the teflon toaster packets or non-stick sheets.
Too smart. Shocked that people don't consider this more for testing and creation of solution. Need to find your video on the resulting mag loop tests with this. - N1KTJ
Same idea as the Gamma match my father built for his stack of two 5-element 2-meter Yagi beams... He used two sizes of tubing, I think one copper and one aluminum (I think the use of two different metals had more to do with local availability more than anything else), with a neoprene or similar tube separating them. Small tube inside the neoprene, neoprene inside the bigger tube. Worked great back then (1995 or thereabouts).
Thank you.
checked current price at Harbor freight. Only 14 dollars for small tail pipe expander or 19 for the large one. It doesnt say what the "exact" size is. So I will just have to visit the store and see. But really, this is a great idea. I live in a HOA controlled area and it is looking like the magnetic antenna(using trombone cap) will be my best option.
Wow, that's nuts the inflation. Now is ~$20 for the medium and ~$32 for the large one. Notes online, "Works with all 1-1/2 in. to 2-1/2 in. mild and aluminized steel pipes" for the medium and "2-1/8 in. to 3-1/2 in." for the large Laguna brand they both are. Was wondering if that meant the pipe size inserted and can expand and if so, what's the amount can expand since doesn't state the pipe thickness and am guessing that standard amount whatever that is.
Great idea with the tailpipe expander. Found you looking for a trombone capacitor. I am thinking it won't be real good for transmit. Probably arc over, but for receive,, very cool.
Yeah, I was wondering what the breakdown voltage is and wondering what different insulator materials performance will do to affect that. Maybe even some lube of some sort might effect, i.e. a teflon or silicone type.
Dang good idea there skippy! thanks
what does a tailpipe expander cost? seems like buying variable capacitors is more frugal.
Beautiful tuning.
How much power will the coke cans handle without arching over...i.e. for use on a magloop?
Great idea. I've made a few of the coke can stoves. Any idea how much voltage it will handle?
Genius!
How did the cap perform? Was it stable? Did you have a problem with leakage? Did you measure the ESR? Did it have an inductive component? I really like your idea.
You mention to "anneal" the can to prevent it from splitting. What is your procedure for that? Thx.
I heated the can up with a torch real quick (2 or 3 seconds) then let it cool
The critically missing piece of info is how to anneal a thin aluminum can. Please add that info; otherwise, following your instructions will probably end in failure.
Why not just split a can, and use duct tape to hold larger diameter?