My foam cutter

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Little Scrapper

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Took a break from my airplane to make a fiberglass fender for one of my motorcycles. Obviously this can be used for airplane stuff.

I know literally ZERO about composite building so this is pure amateur hour here. Anyhow, thought some may enjoy this. Feel free to improve it.

 

proppastie

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17 ga. guitar string...what diameter is that? American Wire Gauge is .045....but when I looked at "17 GA Guitar String" one source said .017 dia. a G string was reported at .017 dia.
 

Little Scrapper

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Guitar string broke although it worked really well.

I went to Ace and bought this roll. It’s .040” stainless and although it worked great I’d definitely use something like .030”?

Stainless welding wire would work great but I’m currently out of it.

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Little Scrapper

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This is what I’m making for the Harley. A cafe of sorts. This is good training for my fiberglass cowling in the Baby Ace. I know nothing about fiberglass molds but my son works for a taxidermist so he’s coaching me a little on molds because he molds fish.

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Little Scrapper

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This hot wire business is kind of addicting. This set up gets a little too hot. I’m done so it’s irrelevant to me now but if anyone follows my video you would be smart to figure out a way to make it less hot. Perhaps a longer bow???? The experts here would know, I’m guessing my way through this.

110EEF91-3680-4378-B1EB-5F3EDC2DE1B0.jpeg2FADAEF8-95C7-486B-9C97-2658946ABE46.jpegD69262FB-B9AB-40BB-8CF8-811BDA4F3975.jpegF7029817-3A8E-48FB-86B4-8A012C6907C8.jpeg
 

Will Aldridge

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This hot wire business is kind of addicting. This set up gets a little too hot. I’m done so it’s irrelevant to me now but if anyone follows my video you would be smart to figure out a way to make it less hot.
It's been close to 10 years so I might remember wrong but I think I bought the electrical "kit" from ACS, but as you can see the heat control is just a dimmer switch. Not sure what the other electrical doohickey is called. 20210411_183537.jpg20210411_183528.jpg
 

Little Scrapper

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It's been close to 10 years so I might remember wrong but I think I bought the electrical "kit" from ACS, but as you can see the heat control is just a dimmer switch. Not sure what the other electrical doohickey is called. View attachment 109500View attachment 109501
See now you have me wondering, what would happen if I built a box with a dimmer switch that I could plug in between the outlet and the charger?
 

poormansairforce

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You don't want to work with live electric that has a ground potential. That's what the transformer above does, it isolates the low voltage side of the circuit. If you get lots of ripples you need a large capacitor and a rectifier to go to DC on the low voltage side. That will smooth it out but not that important on one offs.....
 

proppastie

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I really liked the battery charger....I have one just like it and really is easier than making something from a transformer......I also have a HO model RR transformer and wounder if that would work or if you needed a larger old O ga RR transformer......you might try .025 ss safety wire......or time to re-string your guitar?
 

billyvray

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I did the same, bought a little 120v to 12v transformer and powered by a dimmer- all inside a plastic coffee can.

It's been close to 10 years so I might remember wrong but I think I bought the electrical "kit" from ACS, but as you can see the heat control is just a dimmer switch. Not sure what the other electrical doohickey is called.
 

speedracer

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I've been using the same hotwire setup since 1991 (with several different frames). The key to controlling heat is simply a potentiometer. The best wire IMO is .014 dia. (27 gage) from Jacobs Online. Also, there shouldn't be any ripples in the cut. I've hotwired two sets of LongEZ wing cores with that setup. You can also use multiple wires for doing curves that require less hand shaping.
 

Bill-Higdon

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See now you have me wondering, what would happen if I built a box with a dimmer switch that I could plug in between the outlet and the charger?
Mike,
if the charger was one of the "ancient" transformer & rectifier types it would probably work great. But with the modern "Switcher" style it's a bad idea., I've seen the results of people trying to bring up switcher power supplies on Variacs it's very messy
 

Little Scrapper

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Ok, question.

On kids toys various chargeable type things (shavers etc) they plug in to a wall and convert it to say something like 5 volts right?

Can you get one that is stronger than others in volts and just cut the end off and use it exactly like the bow I made with the alligator clip?
 

Little Scrapper

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Ok, question.

On kids toys various chargeable type things (shavers etc) they plug in to a wall and convert it to say something like 5 volts right?

Can you get one that is stronger than others in volts and just cut the end off and use it exactly like the bow I made with the alligator clip?
Here’s my shaver plug. It says 4 volts FA6FBFDF-D01B-4E34-AC93-B02391953C3D.jpegB4838FE7-0FFA-4EB0-BF8D-E6C5DB291096.jpeg900 mA or milliamps. How can a person figure out how many mA is required for say a 36” line at .020” thick.

I’m the furthest thing from a electrical engineer but it just seems like this could be calculated?
 
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