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1/4 Jack to RCA cable to power supply

notworking

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Hi, I am a tattooist and have questions relating power and cables.

1) Just to get you guys familiar, I have a rca cable where one end is a gold 1/4 jack and the other end is a single male gold rca plug. The 1/4 jack is connected to a power supply and the rca head is plugged into the tattoo machine. Few days ago my tattoo machine just stopped out of nowhere and found out that the rca cable died even though I bought it just a few days ago. I can feel the cable being hot. I checked the continuity and everything was beeping fine on the multimeter. I then checked the current and it didn’t provide the current that it should have. - Does anyone know what happend to the cable? And is there a easy fix to fix it?

2) Also what is the difference between buying expensive cables that have gold plated jack/plug compared to cheap silver plated cables? Or are there all the same? Or can cheap cables able to short and ruin equipment?

3) How can I check if cables or a 90 degree right angle rca adaptor are safe to use on my power supply and tattoo machine? Just wanting to know if there is a way to test so I can avoid anything shorting or ruining my expensive machine. If it is even possible?

4) What are tattoo machine rca cables called? I find not much local shops sell the 1/4 jack to a single male rca head only. The cables that most local shop sells are for video and they have red, yellow, white rca heads which is not what I need. I only need cables with 1/4 jack to single rca head. Are tattoo machine rca cables a special kind of cable? If so hard to find can I make one? If so how?

Thanks!
 

sailor2005

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Just google "tattoo machine RCA power" and quite a few will show up. From there you can choose sellers. If I were you I would stick with cables specifically made for this purpose and not use an audio cable. The connectors might be the same but the cable might have a different gauge.
 

DVDdoug

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How much current is needed (amps or milliamps)?

The current-carrying capability is related to the resistance, which depends on wire gauge (lower gauge is "fatter" wire that can carry more current). The heat is also related to resistance. With a given current, higher resistance results in more heat and more voltage-loss through the cable. Usually the connectors or solder joints at the connectors have the highest resistance so the heat usually concentrates there.

Audio cables & connectors aren't usually designed for "power" so you never see a current rating on an audio cable, but sometimes they give the wire gauge. There are charts on the Internet showing wire gauge, recommended maximum current, and Ohms-per-1000ft.
 
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Bob-23

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2) Also what is the difference between buying expensive cables that have gold plated jack/plug compared to cheap silver plated cables? Or are there all the same? Or can cheap cables able to short and ruin equipment?

Generally, talking about audio cables: I good cable doesn't have to be expensive, and, if gold or silver, that's usually of no importance, except you live in a very humid part of the world. (Silver is a slightly better conductor, but gold, on the other hand, doesn't oxidize as easily as silver).

To tell a good cable from a bad one, is nearly impossible from the outside. You'd have to cut it through, and see how thick it is, and break the connectors to find out if the solder job has been done well. Bad RCA cables often have a very rudimentary outer copper braid (might have been too thin, in your case). Bad cables break easily just behind the connectors. Bad cables wear out quickly, and you're left with loose contacts.

I stopped buying RCA cables, years ago, there's too much rubbish on the market, and prices can be outlandish for the potentially better ones. I buy high quality cable (think I paid 75 ct/m (!) at Segor-Store here in Berlin) and solder the connectors myself. - Only when you do it yourself, you know what you've got.

So, that could be an option for you, if you've got a soldering iron - and you'll be prepared for the next cable break, and the next worn-out plug. As you're working with tattoo machines, your hands should have the necessary skills with them.

EDIT: A shorted cable may damage the power supply.
And, by the way: I'd consider soldering the cable directly into your tattoo machine, thus, circumventing one weak point./plug.
 
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notworking

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Just google "tattoo machine RCA power" and quite a few will show up. From there you can choose sellers. If I were you I would stick with cables specifically made for this purpose and not use an audio cable. The connectors might be the same but the cable might have a different gauge.

Yes I know I can google and buy them online but they take awhile to get delivered and I kind of need a cable now to do some work. And local shops don’t sell them which I think the best way is to start making them. But I have no knowledge on what stuff to get. I can solder but not full good.
 
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notworking

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How much current is needed (amps or milliamps)?

The current-carrying capability is related to the resistance, which depends on wire gauge (lower gauge is "fatter" wire that can carry more current). The heat is also related to resistance. With a given current, higher resistance results in more heat and more voltage-loss through the cable. Usually the connectors or solder joints at the connectors have the highest resistance so the heat usually concentrates there.

Audio cables & connectors aren't usually designed for "power" so you never see a current rating on an audio cable, but sometimes they give the wire gauge. There are charts on the Internet showing wire gauge, recommended maximum current, and Ohms-per-1000ft.

Hmm the rca cable got hot along the wires. How much current that it needs I am not sure but my power supply can give up to around 0-17 Volts DC and 6 amp peak inrush current, 3 amp true RMS continuous current.
Since I might build my own power rca cable can I ask which type of cable to use that is high quality since you say audio cables aren’t meant for power?


Generally, talking about audio cables: I good cable doesn't have to be expensive, and, if gold or silver, that's usually of no importance, except you live in a very humid part of the world. (Silver is a slightly better conductor, but gold, on the other hand, doesn't oxidize as easily as silver).

To tell a good cable from a bad one, is nearly impossible from the outside. You'd have to cut it through, and see how thick it is, and break the connectors to find out if the solder job has been done well. Bad RCA cables often have a very rudimentary outer copper braid (might have been too thin, in your case). Bad cables break easily just behind the connectors. Bad cables wear out quickly, and you're left with loose contacts.

I stopped buying RCA cables, years ago, there's too much rubbish on the market, and prices can be outlandish for the potentially better ones. I buy high quality cable (think I paid 75 ct/m (!) at Segor-Store here in Berlin) and solder the connectors myself. - Only when you do it yourself, you know what you've got.

So, that could be an option for you, if you've got a soldering iron - and you'll be prepared for the next cable break, and the next worn-out plug. As you're working with tattoo machines, your hands should have the necessary skills with them.

EDIT: A shorted cable may damage the power supply.
And, by the way: I'd consider soldering the cable directly into your tattoo machine, thus, circumventing one weak point./plug.

Yes I want to make my own powered RCA cable since there are alot of issues buying from companies even when paying a fair amount. I just bought the tattoo rca cable and it died within the first hour not sure what happened but checked the continuity and it was fine just the current didn’t flow through it. Or could it be because I used a cheap (silver plated jack) foot pedal switch for turning on/off machine. Not sure if silver plated cables/jacks/connections etc can ruin equipment or not.

When making an RCA cable specifically for power, what kind of cable do I buy that is high quality and is the correct cable for tattoo machines? And can I cut off the 1/4 jack and right angled male rca head from the rca cable that died and solder it onto the one I am going to be making?

Soldering it directly to the tattoo machine is not an option because it will void my warranty of the machine.
 
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tomtoo

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Thats why i always say: Never use the same connector for complete different usage of a cable. Its inherently dangerous.
A audio rca cable is not build for currents. And the motor of a tatoo machine needs current.
 

restorer-john

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You'd have to make up a suitable lead. No audio cables are going to be remotely suitable for the tattoo machine.

Yes, customized RCA plugs have found their way into all sort of things- even inside ceramic hair straighteners as rotating/swivelling power cord entry points. See here:
https://audiokarma.org/forums/index...hair-straighteners-pics.778952/#post-10693186

The RCA plug/socket and the 1/4" plug/jack can handle a fair bit of current, but 3A continuous on a typical 1/4" socket would likely be pushing it. The RCAs can handle that (2-3A max cont up to 6A peak), but certainly not shielded audio cable- it will melt for sure.

Get some double insulated 2 core that will fit in the RCA outer shell entry and have a tech (or yourself) solder up a nice lead to do the job.
 

tomtoo

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A typical line-in impedance is around 10k Ohm. With 2v you have currents arround U/R=0.0002A. So even the cable would have been build with 1000 times more for security, this would be 0.2A.You like to use a audio cable with 20000 times the current it needs to have build for in the intendet audio application.Just to give you a hint why its not such a great idear to use a typical audio cabel even the same plug is used.
 

somebodyelse

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If you're trying to source cable locally then any mains flex should be fine for the current, and the supplier should be able to tell you what current it's rated for. More generally you're looking for conductors with AWG of 22 or less, or cross sectional area of at least 0.33mm² (assuming it's copper) to handle the 3A continuous current. If the connectors on your existing cable are soldered you should be able to reuse them, assuming they haven't been damaged.

The other bit that will be important to you is the cable handling feel, but I don't think we have any specifications for that. It's something that guitar and microphone leads usually do well, but they can't usually handle the current you need. The silicone insulated cable that's often used for soldering irons would probably be good.
 

restorer-john

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The silicone insulated cable that's often used for soldering irons would probably be good.

Excellent idea. :)

Most LV irons are about 60W and the Chinese copies of Hakko irons can be bought for around $10 delivered* to your door, complete with tip, handle and cable-plug. The silicone cables usually have 4-5 conductors, so you could easily parallel two pairs to increase the current capability and reduce the V drop. The only thing might be length- you may need a 2M plus length?

*How do I know? My previous Birman cat absolutely loved Hakko iron silicone and cost me at least 4 replacement cables from Hakko at $50 a pop. I ended up buying cheap Chinese copies just for the silicone cable...
 

somebodyelse

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Ah...ye joy of cats! At least Antex sell the bare replacement cable, but the 5 core costs more than your whole cloned iron! The 3 core is cheaper and a bit longer, but still only 1.5m.
https://www.rapidonline.com/Iron-Cables
I think every silicone or rubber insulated mains flex I've encountered handles well, so there should be more cost effective options that don't have the length limitation. The trick will be finding a supplier that will sell by the meter rather than the whole reel.
 
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