Heat-Shrink" Tubing Material

[Jeffry Fontaine]

Has anyone tried to use Heat-Shrink tubing material on a tank main gun barrel to simulate insulated/thermal wrap covering? 

This would be for modifying a tank main gun barrel for example the M68 105mm gun as used on the M48A5 and M60A1 Patton III/Patton IV tanks. 

Curious to know if anyone has had success with this or am I going down a new untraveled path. 

[Buzzbomb]

Has anyone tried to use Heat-Shrink tubing material on a tank main gun barrel to simulate insulated/thermal wrap covering? 

This would be for modifying a tank main gun barrel for example the M68 105mm gun as used on the M48A5 and M60A1 Patton III/Patton IV tanks. 

Curious to know if anyone has had success with this or am I going down a new untraveled path.

I for one am interested in how the experiment goes, as it sounds plausible. Would have to be a metal barrel though if you apply heat to shrink I would think.

[Frank3k]

I can try it. The heat required for Polyolefin heat shrink to shrink is close to the temperature styrene and ABS soften (100C/212F for styrene/ABS and 90C/194F - 120C/248F for the shrinking to happen). Heat shrink tubing thickens as it shrinks and the end can pucker a bit. It'll be an interesting experiment, but don't have much hope that it'll work.

I have heat shrink tape somewhere. I'll try that as well, if I can find it.

[Jeffry Fontaine]

Hi Frank. 

I too was concerned about the heat required and quickly dismissed the idea of trying it with a plastic gun barrel.  I figured it might be a work-around for a metal gun barrel to bring it up to more modern standards.  I blame this on watching a recent video on the M41 Walker light tank as it just begs to be improved upon and the insulated gun barrel is one of those things that the majority of modern tanks have as a standard feature.  Some of the AFV Club kits have a metal aluminium gun barrel included which makes it possible to do this modification.  Like you, I have the heat-shrink tubing somewhere, need to find it. 

[Mig Eater]

Intriguing idea, I'd be interested to know the results too

[Frank3k]

The results weren't promising, at least with a plastic barrel. The barrel is from the Meng Leopard C2 Mexas. This barrel already has a protective heat shield on it, but it's all I had handy. Sorry for the out of focus pictures

Standard heat shrink tubing that fits snugly over the barrel:



I used a hair dryer to heat the shrink tubing. It shrank, but I stopped it when I felt that the barrel was getting hot enough to start deforming:



I sliced it open and the inside of the tubing had copied some of the details of the barrel, so that was encouraging.

Next, I tried some heat shrink tape. I wrapped it lengthwise along the barrel. The tape is slightly self sticking and is designed to wrap tightly around pipes or wires, but it was difficult to wrap the tape in this orientation. Even cold it showed some details from the barrel, but it had the same problem as with Polyolefin heatshrink tubing.

Wrapped as tight as tight as I could get it:



After heating:



The technique may work on metal barrels. I may have one that I can try this on; I'll look for it tomorrow. For plastic barrels, I think something like Tamiya tape would work OK.

[Jeffry Fontaine]

Thanks for taking one for the team Frank. 

The bare metal gun barrel without thermal shroud is what I was looking to improve upon.  The candidate gun barrels are the 60mm gun from Oto/IAI, the 76mm gun barrel from the M41, and the 105mm gun barrel from the M60A1.  The 60mm gun barrel was never given a thermal shroud as far as I can tell.  The 76mm gun barrel may have received a thermal shroud while in service with Taiwan, and the M60A1 gun barrel is always in stock while the M60A3 gun barrel is always out of stock at the usual suspects on-line. 

[Frank3k]

Jeff, I'm almost certain that I have an Aber T-90 125mm metal barrel. I'll use that for the next test. It will almost certainly work, since this is what both the tape and tube heat shrink materials are designed for. The question is what will you use for the brackets/straps for the blanket/shroud.

[Jeffry Fontaine]

Hi Frank. 

That might be over-kill on adding the heat-shrink tubing to the T-90 125mm gun barrel.  Since that part has the thermal shroud features already applied to the barrel during production it might make the gun barrel look a bit over-insulated with the heat-shrink added to it. 

I was looking to add the insulating wrap feature to a bare barrel, one without the thermal wrap to upgrade it.  That said, it will be interesting to see how much different the T-90 barrel will look with the additional material wrapped around the gun barrel.  From what you demonstrated with the plastic Leopard MEXAS gun barrel it was definitely hit and miss on the overall effects. 

Harbor Freight has heat-shrink tubing in stock so I can go into town today and pick some up. 

The other option was found at Amazon.com for a kit containing 400 pieces for about $14.00. 
Link: Amazon.com > The Electronic Store > 400 Pcs Heat Shrink Tubing Kit-3:1 Ratio Adhesive Lined,Marine Grade Shrink Wrap - Industrial Heat-Shrink Tubing - Black  

My concern with this product is the adhesive lining inside of the tubing material.  Not sure that is something I want to apply to the gun barrel or not.  It might be beneficial or it may be an obstacle.  The positive is that there are some very small diameter heat-shrink tubing sizes that are ideal for 1/35th scale gun barrels.  While the 19mm tubing may work well for a rocket motor body/casing covering it definitely has limited uses in modeling. 

Also hope that the heat-shrink is easy to remove from the gun barrel if it does go wrong in application.  That might be a problem with the Amazon product.