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Decoder without shrink wrap

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Posted by snjroy on Sunday, July 26, 2015 7:09 AM
For these situations, I have used wide heat sink material, keeping one end open for ventilation.







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Posted by Graham Line on Wednesday, July 22, 2015 3:20 PM

If you are messing around with decoder installation at all, Kapton tape is an essential tool. Other tapes will fail or cause problems.  Litchfield Station sells a small roll of Kapton tape for $2.50, and other dealers have similar offers. My local hobby store will sell it by the foot, wrapped around one of the store's free pens.

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Posted by mfm37 on Saturday, July 11, 2015 2:30 PM

Lenz has never used a covering on their decoders. They don't recommend covering their decoders because of heat. Just insulate any thing it will come in contact with that will short it.

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Posted by jjdamnit on Saturday, July 11, 2015 2:07 PM

Hello All,

Just bought a roll of Kapton tape (20mm [3/4-inch] x 33m) on eBay for $4.89 (with free shipping). It arrived in 5-days.

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

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Posted by hon30critter on Sunday, June 28, 2015 11:28 PM

Mike and Don H:

Thanks for your answers to my question about Kapton tape on a Loksound Select Micro. Sorry it took so long to get back to you.

The ends are open, and there is actually a fair sized vent right above the decoder which was part of the prototype's design, so I won't worry. As Don said, if it shuts down, then I'll worrySmile, Wink & Grin.

Dave

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Posted by Mark R. on Sunday, June 28, 2015 12:05 PM

BroadwayLion

 

 
Mark R.
Didn't know Lions could back-pedal. Maybe lions should keep suggestions to themselves when they have no experience in said topic. No answer is better than wrong answer ..

 

LION made post no. 2. OPO asked about electrical tape and the LION told him NO! LION might not use DCC, but LION does work with computers and Mother Boards and Junior Boards, and gave a suggestion as to what him would do in that case. You want not the electrics to touch something, and you want something that could be easily removed. Cutting a folder from an anti-static bag that a hard drive came in would have been a good idea too, but LION thought it easier for OP to get tape from pharmacy than electrostatic bag from somewhere.

ROAR

 

And again, you don't understand the situation at hand and making a poor suggestion. The problem with the TSU-750 is not electrostatic protection, but rather heat dissipation. These decoders - unlike most any other decoder - run HOT. That's why they have that plate inside the shrink wrap - to try and dissipate some of the heat. Wrapping this decoder in ANYthing that won't dissipate heat is asking for trouble.

An anti-static bag does not dissipate heat. General knowledge of non-related subjects does not always translate well to a specific subject at hand and could cause more harm than good. I can paint model trains very well, but I would never consider giving advice on painting a car ! ....

Mark.

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Posted by BroadwayLion on Sunday, June 28, 2015 11:26 AM

Mark R.
Didn't know Lions could back-pedal. Maybe lions should keep suggestions to themselves when they have no experience in said topic. No answer is better than wrong answer ..

LION made post no. 2. OPO asked about electrical tape and the LION told him NO! LION might not use DCC, but LION does work with computers and Mother Boards and Junior Boards, and gave a suggestion as to what him would do in that case. You want not the electrics to touch something, and you want something that could be easily removed. Cutting a folder from an anti-static bag that a hard drive came in would have been a good idea too, but LION thought it easier for OP to get tape from pharmacy than electrostatic bag from somewhere.

ROAR

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Posted by cacole on Sunday, June 28, 2015 10:11 AM

The simplest solution is, throw that decoder away and purchase a new one.

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Posted by dante on Saturday, June 27, 2015 10:25 PM

If you have a LHS that does electronics work, they might give or sell you a small hunk of Kapton from the roll they have open and use. Or buy a roll from TCS or some such outfit. I am almost certain you will find other uses for it in the future.

Dante

 

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Posted by Mark R. on Saturday, June 27, 2015 8:26 PM

BroadwayLion

 

 
Mark R.
Which is why the LION wrapped it in Coban tape.

 

LION did not say him used DCC, him was offering a suggestion for installing a non-wrapped DCC, and after much conversation,  we came back around to the suggestion that I made.

LION does all kinds of electronics, but mostly with 'puters. Has boxes and boxes of surply cards. Him said not to use electrical tiape, and that of course still stands.

 

ROAR

 

 

Didn't know Lions could back-pedal. Maybe lions should keep suggestions to themselves when they have no experience in said topic. No answer is better than wrong answer .... Smile, Wink & Grin

Mark.

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Posted by rrinker on Saturday, June 27, 2015 6:17 PM

richg1998

Here is a photo of the heat sink. You can see the impression of the chips. I peeled at little away on the right side and lower left. The brown is the insulation. The aluminum plate is under the brown layer.

Not interested in bashing SoundTraxx. Have never run a decoder company and the tsunami is at least ten years old. SoundTraxx is coming up with new decoders.

Rich

 

 

 That is much better, at least the thermal material does press down on the chips as it's supposed to. Is this a blown one, or have you trued using it in free air, just the bare board without the heat sink, to see if it might stay cool better (not unheard of with other electronics)?

                --Randy


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Posted by tedski on Saturday, June 27, 2015 6:09 PM

I looked up the Kapton tape and its expensive and comes in long rolls.  Since I only need a bit, I can't justify buying so much.  Is there a good alternative or should I just go with the initial suggestion of wrapping the chip and heatsink together with a small strip of Coban.  I'm thinking I would put a strip around the two pieces like a wide belt.  It would keep the pieces together and yet give it a lot of opportunity to breathe. 

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Posted by richg1998 on Saturday, June 27, 2015 6:03 PM

Here is a photo of the heat sink. You can see the impression of the chips. I peeled at little away on the right side and lower left. The brown is the insulation. The aluminum plate is under the brown layer.

Not interested in bashing SoundTraxx. Have never run a decoder company and the tsunami is at least ten years old. SoundTraxx is coming up with new decoders.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

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Posted by BroadwayLion on Saturday, June 27, 2015 5:56 PM

Mark R.
Which is why the LION wrapped it in Coban tape.

LION did not say him used DCC, him was offering a suggestion for installing a non-wrapped DCC, and after much conversation,  we came back around to the suggestion that I made.

LION does all kinds of electronics, but mostly with 'puters. Has boxes and boxes of surply cards. Him said not to use electrical tiape, and that of course still stands.

 

ROAR

 

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Posted by gregc on Saturday, June 27, 2015 2:40 PM

Mark R.
I think your wife has a mis-understanding what Kapton tape is. It is a transparent yellow tape that is designed for thermal transmission ....

at least scotch tape and i believe most tapes when pulled away from an  adhesive coating, can generate a large static charge that can damage electronic components.

We use Kapton tape on electronic circuit boards because it apparently does not create a static charge.

greg - Philadelphia & Reading / Reading

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Posted by Mark R. on Saturday, June 27, 2015 2:12 PM

BroadwayLion

 

 
Mark R.
If you've already damaged or removed the wrapper, I wouldn't be very concerned about wrapping it back up again. Let it breathe the fresh air ! Just make sure none of the exposed contacts can short out on anything metal nearby.

 

Which is why the LION wrapped it in Coban tape.

ROAR

 

When did Lion start using decoders ?

Mark.

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Posted by BroadwayLion on Saturday, June 27, 2015 2:03 PM

Mark R.
If you've already damaged or removed the wrapper, I wouldn't be very concerned about wrapping it back up again. Let it breathe the fresh air ! Just make sure none of the exposed contacts can short out on anything metal nearby.

Which is why the LION wrapped it in Coban tape.

ROAR

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Posted by richg1998 on Saturday, June 27, 2015 11:58 AM

rrinker

 

 
richg1998

I am very suprised you bought a new 750 with no insulation.

You have been given good advise.

Below are two photos of a stock 750 I took. You can see the heat sink is insulated material bonded to a metal strip. A little heat sink paste is used. The heat sink presses up agains the two large chips.

Rich

 

 

 

 

 

 

 And if that tiny little dot is all that gets touched on the big chip, no WONDER they have heat issues. You need a complete, even contact between the heat sink and chip for effective heat transfer. That little bit that touches on the corner does pretty much nothing. The contact patch on the other chip is a little better but still way too thick.

                      --Randy

 

 I wish you would have not posted that Randy. Those white marks look like white paint.

The adhesive is like a layer of tape and most stayed on the heat sink.

Forgot to mention. The outline of three chips are firmly in the adhesive thermal tape.

That layer of thermal adhesive is similar to a tape, it is on a layer of insulating material and the metal heat sink is on the bottom which is again the heat shrink. The photo does not do it justice.

Rich

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Posted by Mark R. on Saturday, June 27, 2015 11:57 AM

Decoders are shrink wrapped for one purpose - to prevent the loose decoder from shorting out on something in case it moves around. While you may - in most cases - void the warrantee if you remove it, the decoder will run cooler without it as opposed to being wrapped, even though the wrapper is designed to dissipate heat.

If you've already damaged or removed the wrapper, I wouldn't be very concerned about wrapping it back up again. Let it breathe the fresh air ! Just make sure none of the exposed contacts can short out on anything metal nearby.

Mark.

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Posted by CSX Robert on Saturday, June 27, 2015 11:50 AM

rrinker
And if that tiny little dot is all that gets touched on the big chip, no WONDER they have heat issues...

I'm pretty sure that white dot is just a spot of paint to highlight pin 1 of the chip, not the heat sink paste.  Likewise, on the other chip, that's just a paint mark.

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Posted by Mark R. on Saturday, June 27, 2015 11:48 AM

I think your wife has a mis-understanding what Kapton tape is. It is a transparent yellow tape that is designed for thermal transmission ....

Mark.

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Posted by tedski on Saturday, June 27, 2015 11:04 AM

I want to add in a bit more information.  The 750 is new, I bought it.  I removed the purple shrink wrap, the reason for which I am too embarrassed to tell.  There is a metal strip in there as pictured above that serves, I think as a heatsink. There is a paste on the metal strip  facing the chips that looks like it is a layer of thermal paste. 

When the Capton tape was mentioned, I asked my wife if she had ever heard of the stuff.  She said of course she had and she had some.  My wife is a physical therapist and uses the stuff.  So I will try this first as a way of holding the chip and metal sink together.  Looking at the tape its cloth and stretches. Spaces are opened up as you would see when stretching a fabric.  I asked my wife if heat would escape these spaces and she said yes if only one layer was put on.  Wrap it twice and it will be nice and toasty in there.  So, I guess I'll try one layer of tape as well as leaving the ends open. 

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Posted by rrinker on Saturday, June 27, 2015 10:11 AM

richg1998

I am very suprised you bought a new 750 with no insulation.

You have been given good advise.

Below are two photos of a stock 750 I took. You can see the heat sink is insulated material bonded to a metal strip. A little heat sink paste is used. The heat sink presses up agains the two large chips.

Rich

 

 

 

 

 And if that tiny little dot is all that gets touched on the big chip, no WONDER they have heat issues. You need a complete, even contact between the heat sink and chip for effective heat transfer. That little bit that touches on the corner does pretty much nothing. The contact patch on the other chip is a little better but still way too thick.

                      --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by DigitalGriffin on Saturday, June 27, 2015 10:03 AM

hon30critter

 

So, will the decoder suffer from heat build up with the Kapton tape around it?

 

If it overheats (shutsdown) that's your first clue.  Since it's already installed I wouldn't worry about it till it shut down.  If that happens find some thermal pads or thermal adhesive like I linked above.

Thermal pads are less effective, but they are easier to remove.

Edit Found the thermal pads:
http://www.newegg.com/Product/Product.aspx?Item=9SIA4SR1WU0018&cm_re=thermal_pad-_-0SS-004J-005H0-_-Product

Don - Specializing in layout DC->DCC conversions

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Posted by mlehman on Saturday, June 27, 2015 2:04 AM

If the ends are open, Dave, I see no problem.

But if you trussed it up like a Xmas package, that's not so good.

Mike Lehman

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Posted by hon30critter on Friday, June 26, 2015 10:18 PM

I would like to ask a related question.

I recently re-installed a Loksound Select Micro using Kapton tape instead of the original shrink wrap. The original wrap was too messed up to use because I had used CA to mount the decoder originally and when I had to remove it the wrap was broken. I actually had to remove it twice which explains why the original wrap got destroyed. (Yes, I used too much CA! I have learned!!).

So, will the decoder suffer from heat build up with the Kapton tape around it?

Thanks

Dave

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Posted by Mark R. on Friday, June 26, 2015 9:46 PM

I'd be a little suspicious about this decoder being brand new. If I recall correctly, you void the warrantee on the decoder if the shrink wrap is removed.

By all means mount the TSU-750 to a heat sink. They run at a very high clock rate, which means they run hot ! Without a heat sink, you will be plagued by it constantly shutting down from thermal overload.

Mark.

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Posted by richg1998 on Friday, June 26, 2015 2:24 PM

I am very suprised you bought a new 750 with no insulation.

You have been given good advise.

Below are two photos of a stock 750 I took. You can see the heat sink is insulated material bonded to a metal strip. A little heat sink paste is used. The heat sink presses up agains the two large chips.

Rich

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Posted by mlehman on Friday, June 26, 2015 11:31 AM

Don's suggestion to add a heat sink is a good one and is frequently employed by narrowgaugers.

I've seen thermal paste, but it's not always adhesive. In either case, after you get the heat sink where it should be, you can take a big enough piece of shrink and apply it over everything. This way you both have a heat sink and prevent any shorts. Don noted you can apply it directly to the brass shell of a tender or loco, but be sure to check for shorts on the programming track just to be sure if you do it that way

One trick we narrowgaugers use with the -750 is to reduce the voltage on the DCC system if that's what you're using. Most run around 14 volts from the factory. Turning that down in your command station will help the decoder run cooler. Mine is set at 12.5 volts and I've had no overheating trouble with any of my -750s.

Mike Lehman

Urbana, IL

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