Author Topic: Insulating Wire-to-Resistor Joints?  (Read 1122 times)

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Lemosteam

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Re: Insulating Wire-to-Resistor Joints?
« Reply #15 on: March 02, 2017, 08:42:25 AM »
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jdcolombo

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Re: Insulating Wire-to-Resistor Joints?
« Reply #16 on: March 02, 2017, 09:12:16 AM »
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Russ -

I'd like to steer you back to SMD's.  You don't have to etch boards to use them.  I switched to using them on a small piece of circuit board, which I mount on the flat part of the LokSound (toward the front).  I use 1/32" single-sided board, and all I do is cut a horizontal line where I want to separate "circuits" (e.g., for the white and yellow wires), and then cut a vertical line where the smd resistor will go.  Then I cut this small piece from the larger PCB, tin what are now 4 distinct pieces of copper, solder on the resistors, and now I have a place to solder the LED wires in any direction I want.  Four two lighting circuits, my piece of PCB comes out to about 1/4" x 3/8" although it could probably be made smaller.

These days I cut the lines in the board with a 1/64" end mill on my Proxxon milling machine.  But you can also do it with a thin cutoff wheel in a dremel, or even with a hobby knife.

Given what you are doing (using lots of LEDs with the necessary dropping resistors), this actually might be your best bet.  Here are some photos of how I do this:

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Photo 1 shows a larger piece of board with the lines cut through the copper; then the next photo shows these cut into separate peices with two "circuits" each.  The final photo shows the pieces with the 1/8 watt SMD resistors soldered on.  At this point, the pieces can be trimmed in length with a pair of end-nippers - just nip off the excess length until you have them the length you want (heck, you could trim these to 1/64" beyond the ends of the resistor without any trouble).  If you are using 4 lighting circuits, you can put two of these smaller boards side-by-side and have your four circuits.  Or you can make a board that is 4-circuits deep.  And since they are so thin (the board itself is 1/32", the SMD resistor is about the same), they fit pretty much anywhere.  I know it sounds daunting, but it really isn't, and I've found that doing it this way offers much more placement flexibility because you aren't tied to soldering leads on regular round carbon resistors.

John C.

Doug G.

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Re: Insulating Wire-to-Resistor Joints?
« Reply #17 on: March 02, 2017, 11:44:50 AM »
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Pretty much the standard for years to cover bare leads has been vinyl insulation stripped from wire. Many a Heathkit had steps to do just that.

Doug
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tehachapifan

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Re: Insulating Wire-to-Resistor Joints?
« Reply #18 on: March 02, 2017, 01:29:52 PM »
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Thanks for all the ideas, guys! :D
Russ

peteski

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Re: Insulating Wire-to-Resistor Joints?
« Reply #19 on: December 21, 2018, 09:13:32 PM »
+1
Since the info is topical for this thread, I'm copying my post on another thread to this thread.

While I'm a big proponent of using a PC Board to hold SMD resistors, in my previous post I just mentioned dong the same thing you did with a regular (through-hole) resistor but using SMD resistor. This is what I meant:



In this example I used a 1206 size resistor.
The top part of this photo view shows the parts.  Decoder wire is stripped (on the left), tinned, bent at 90 degrees and trimmed (on the right).
Middle part of the photo shows the wires soldered directly to the SMD resistor. The metalized ends are quite robust and the resistor is also made of solid ceramic material.
Bottom part of the photo shows it with a piece of clear heat-shrink tubing insulating the assembly. But you could just coat it with your liquid tape with the same result. This is a more compact assembly than using a through-hole resistor.
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Steveruger45

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Re: Insulating Wire-to-Resistor Joints?
« Reply #20 on: December 21, 2018, 10:59:28 PM »
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I usually make a small pcb for the resistor and it’s led both smd type on the same small board. If insulation needed too I apply liquid tape.  Old cut and modified dc boards work too.
« Last Edit: December 21, 2018, 11:02:13 PM by Steveruger45 »
Steve
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nickelplate759

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Re: Insulating Wire-to-Resistor Joints?
« Reply #21 on: December 22, 2018, 08:39:46 AM »
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Pete,

That's slick. How do you hold everything in place while you solder?   If the resistor and widescreen as large as your picture makes them seem it would be easy, but....
George

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I'm sorry Dave, I'm afraid I can't do that.

narrowminded

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Re: Insulating Wire-to-Resistor Joints?
« Reply #22 on: December 22, 2018, 10:40:34 AM »
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A very small drop of CA on the body, not the solder pads, will hold a device while soldering.  On PC boards, solder and you're done.  If you are hardwiring, a very small drop of glue on the dining room table or some other suitable surface, then tape, clips, weights, will steady the wire.  Pop the device off the table when done. 8) 
Mark G.

David K. Smith

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Re: Insulating Wire-to-Resistor Joints?
« Reply #23 on: December 22, 2018, 11:03:31 AM »
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These days I cut the lines in the board with a 1/64" end mill on my Proxxon milling machine.  But you can also do it with a thin cutoff wheel in a dremel, or even with a hobby knife.

This is what I do, using a knife to cut the traces apart. It works for everything from small boards (as John C. demonstrated) to larger stuff, like this gas station roof:



..and is suitable for SMDs, wire resistors, etc.

Pretty much the standard for years to cover bare leads has been vinyl insulation stripped from wire.

This. Especially since it's free.

« Last Edit: December 22, 2018, 11:06:07 AM by David K. Smith »
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peteski

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Re: Insulating Wire-to-Resistor Joints?
« Reply #24 on: December 22, 2018, 01:42:13 PM »
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Pete,

That's slick. How do you hold everything in place while you solder?   If the resistor and widescreen as large as your picture makes them seem it would be easy, but....

I use either Scotch (3M) clear mounting tape or just a loop of blue masking tape (with adhesive side out) to hold the item being soldered.  I put the tape on a piece of wood or metal large and heavy enough not to move while I'm soldering, but small enough for me to easily position on the workbench (rotating it for best position for soldering).

This is the stuff.


There used to be only one "flavor" of it, but now there seem to be couple variants. I have only used the one with red separator.
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