Welcome to the Solar Collector
Brainstorming and Development Page!


 

Home

Hot Air Collector

Hot Water Project 1

Hot Water & Space Heating

Solar Electric

Solar Construction 101

FAQs

Best Collectors

Simply Solar
Register Calendar Latest Topics
 
 
 


Reply
  Author   Comment   Page 4 of 8      Prev   1   2   3   4   5   6   7   Next   »
stmbtwle

Avatar / Picture

Registered:
Posts: 2,782
Reply with quote  #31 
Somehow I don't think that would help, we're playing with fire here.
Maybe afterward to celebrate success? [smile]


Update: IT WORKS!!! I tried it with a propane torch and a pop can.

Use just enough heat to brown the paint, you don't have to burn it off.
Nor do you have to do the entire can, just the part you want to bend.

Pop cans are awfully thin, though, don't know how good they'll be at transferring heat.

Time for a rum & coke! [smile]

__________________
Solar is like the wind. It may be free, but putting it to work isn't!
Willie, Tampa Bay

Rick H Parker

Avatar / Picture

Registered:
Posts: 762
Reply with quote  #32 
"Update: IT WORKS!!! I tried it with a propane torch and a pop can."

How it is soft and will not hold its form well.

You could form it then quench it to get it hard it in the form you want. Getting the temperatures right to avoid warping, distortion and embrittlement is an art form.

I would not do it all all, Copper and Aluminum are dissimilar metals, as a pair they are highly susceptible to galvanic corrosion.

__________________
Rick H Parker
Kansas, USA
Electronics Engineering Technologist
Onoff

Registered:
Posts: 41
Reply with quote  #33 
I tried with my MAP torch. You have to be very careful and quick as it's so hot. Get it wrong and the ali turns up. Also a danger of it getting too hot then it becomes brittle and can split. Madam's oven I reckon could be the answer!

34210411611_64ebee2618_z.jpg 

34300093006_84ba719317_z.jpg 

34340864295_7fd2942fb7_z.jpg 

Over here people tend to paint the copper pipes first then add the clip fins with a smear of silicon to try and keep the air out and limit electrolytic reaction.

And.....would you believe on the back of all my new found enthusiasm for solar thermal somebody has offered me these for free. Fully working, they are having a new roof and won't be refitting them:

34210394691_594631222b_z.jpg 

I clearly pays to help others. I've done a few favours of late. Karma and all that! I'm collecting them Monday.

Rest assured it won't stop me playing with the DIY versions. [smile]

stmbtwle

Avatar / Picture

Registered:
Posts: 2,782
Reply with quote  #34 
Quenching in water doesn't harden aluminum, at least not pop cans. Tried it. Probably not needed anyway.

Generally there's a coat of silicone between the tube and the fin for heat transfer. That will also prevent metal to metal contact and should keep electrolysis to a minimum. I really don't think it'll be a problem.

GREAT FIND on the collectors, congratulations! Evacuated tube?

__________________
Solar is like the wind. It may be free, but putting it to work isn't!
Willie, Tampa Bay
Onoff

Registered:
Posts: 41
Reply with quote  #35 
Quote:
Originally Posted by stmbtwle
Quenching in water doesn't harden aluminum, at least not pop cans. Tried it. Probably not needed anyway.

Generally there's a coat of silicone between the tube and the fin for heat transfer. That will also prevent metal to metal contact and should keep electrolysis to a minimum. I really don't think it'll be a problem.

GREAT FIND on the collectors, congratulations! Evacuated tube?


Yes EV tubes. 90 miles each way to collect. All 3 will go in the back of the estate (stationwagon) with the seats down. I knew I kept that giant roll of bubble wrap for a reason!
Rick H Parker

Avatar / Picture

Registered:
Posts: 762
Reply with quote  #36 
"That will also prevent metal to metal contact and should keep electrolysis to a minimum. I really don't think it'll be a problem."

The two metals don't need to touch each other to do electrolysis. The two metals just need to be bridged by the electrolyte .... in a battery the cathode does not touch the anode, reason it out.  Matter of fact that was the problem with the exploding lithium batteries, the cathode was growing spikes poking the membrane and coming in contact with the anode.

__________________
Rick H Parker
Kansas, USA
Electronics Engineering Technologist
Rick H Parker

Avatar / Picture

Registered:
Posts: 762
Reply with quote  #37 
"All 3 will go in the back of the estate (stationwagon) with the seats down. "

The pickup, European style.

__________________
Rick H Parker
Kansas, USA
Electronics Engineering Technologist
Onoff

Registered:
Posts: 41
Reply with quote  #38 
Quote:
Originally Posted by Rick H Parker
"All 3 will go in the back of the estate (stationwagon) with the seats down. "

The pickup, European style.


Pretty sure what you guys call a pick up so do we, a small, open backed truck.

What we call an estate car...think Clark Grizwold's car!
Rick H Parker

Avatar / Picture

Registered:
Posts: 762
Reply with quote  #39 
My understanding is the pickup truck did not catch on in europe like it did in the U.S. You guys don't get the pickup ... I not sure most Americans get them but they sure do like them.

Pickup trucks are exempt from the US gas guzzler excise tax of 1978. They became our replacement for the muscle cars of the 50s, 60s and 70s

__________________
Rick H Parker
Kansas, USA
Electronics Engineering Technologist
stmbtwle

Avatar / Picture

Registered:
Posts: 2,782
Reply with quote  #40 
Not impressed with the fuel bill, though, so I drive a hybrid SUV.


"The two metals don't need to touch each other to do electrolysis. The two metals just need to be bridged by the electrolyte .... in a battery the cathode does not touch the anode, reason it out. Matter of fact that was the problem with the exploding lithium batteries, the cathode was growing spikes poking the membrane and coming in contact with the anode."

Actually, the anode & cathode DO have to touch or be connected, just like in your lithium battery. The electrolyte is only half the circuit. Without the other half, some batteries will maintain their charge for a long time. The silicone is neither an electrolyte nor a conductor. Any electrolysis that might happen will be on the aluminum fins, which in a DIY collector are NOT brazed,welded, or soldered to the copper, and therefore NOT completing the circuit (might be a good thing). They're also cheap and relatively easy to replace. It is, after all, a homebuilt, built on a budget. No one expects it to last forever.

__________________
Solar is like the wind. It may be free, but putting it to work isn't!
Willie, Tampa Bay
Previous Topic | Next Topic
Print
Reply

Quick Navigation:

Easily create a Forum Website with Website Toolbox.

 

web statistics