Good news: I was right about transformer winding selection. I switched to the heavy gauge secondary winding, and all is well. I can now crank the thing up as high as my household circuit breaker allows.
Bad news: As I feared might happen, the cutting wire became brittle at high temperature and snapped during my first test at a higher voltage!
In anticipation of this problem, I had prepared a quarter inch copper tube with a length of nichrome wire running through it, electrically insulated by a high temperature fiberglass sleeve. The idea, suggested by Lars, is that the tube, not the wire, bears the brunt of the ice pushing against it (stainless steel would be ideal, but copper was fine for testing). This certainly allowed the wire to get very hot; I could see it glowing brightly right through the fiberglass sleeve! It even left a couple of black marks on the sleeve. Unfortunately, it didn't produce enough heat to cut at a useful speed due to the wide swath of ice that must be melted for the tube to pass through. Maybe a narrower tube could be used, but I haven't found a smaller high temperature insulator to keep the current running through the wire and not the tube.
Then I tried a new length of nichrome in the original setup to see how it works at lower voltage. I adjusted the tension somewhat lower too. I was able to cut at a reasonable speed (at least two inches per minute) with 14V across eight inches of wire, but I had another breakage when I turned it up to 16V. It cuts more slowly than I had hoped, but it is certainly usable.
Two inches per minute may sound quite slow, but I believe it is faster than the boiler we used last year with some success. The benefit of this technique is the ability to make precise, intricate cuts that are perfectly perpendicular (or at some consistent angle) to a surface of the workpiece. For many mechanical parts this benefit could outweigh the slow cutting speed.
Next I would like to try a lower gauge cutting wire which should fail at a higher power level. My guess at this point is that the tension doesn't matter much (the second break happened under very little tension) but that the breakage occurs due to the wire becoming so brittle at high temperature that very little physical stress causes it to break. The failures tend to be located at the hottest part of the wire, between the ice and the alligator clips that deliver current. I'd also like to try to minimize that gap, but it can't be completely eliminated.
7 comments:
what about "braiding" or twisting more than one piece of wire together? That'd strengthen it a bit, no?
The only thing is that it might need more power, since there'd be more resistance (right?)...
Good idea! I suspect that it wouldn't do much better than a single piece of thicker wire, but I'll give it a try if the 16 AWG stuff I ordered doesn't work out.
It would actually decrease the resistance, increasing the current and power for a given voltage (same as thicker wire). This would be good as I would like to be able to take advantage of my mammoth power supply!
Excellent post share with us and this blog is impresses more people to reading that blog.
Agen Bola
Excellent post.I want to thank you for this informative read, I really appreciate sharing this great post. Keep up your work.poker online
poker online indonesia
Only aspire to mention ones content can be as incredible. This clarity with your post is superb and that i may think you’re a guru for this issue. High-quality along with your concur permit me to to seize your current give to keep modified by using approaching blog post. Thanks a lot hundreds of along with you should go on the pleasurable get the job done.
Thanks for the blog loaded with so many information. Stopping by your blog helped me to get what I was looking for.poker online terpercaya
I was scammed over $93,100. I talked with this guy for 8 months. I sent him money via Bitcoin atm and bank account, I almost lost everything. But for the timely intervention of the Wizard Wierzbicki Programmer, who just in kick-off on time got back my $93,100. He is really good at what he does, I have recommended him to friends and co-workers who all became satisfied customers. He has helped me a lot in the trading industry, you can reach him for Everything. Hacking and Funds Recovering he is the best and has different skills in funds recovering and exposing scammers. Am glad and happy to recover my money, there is no shame in becoming a scam victim of one of these sophisticated and predatory operations. By reporting you may be able to recover some or all of your lost funds and prevent the scammers from targeting others. To recover your Bitcoin Scammed funds, Scammed funds, Clear or Erase Criminal Records, Mobile spy remote control assess, Bitcoin Mining Contact this Genius Recovery Advocate Website: https://wizardwierzbicki.com WhatsApp: +49 1575 8718600 Email: WIZARDWIERZBICKIPROGRAMMER@GMAIL.COM
Post a Comment