Mini Hot Air Gun

[DafyddElvy]

Does anyone have any experience of using a mini hot air gun on a model to bend/reshape part of a body?

I am contemplating one and wondered what the thoughts of others might be, thanks?

 

[dunnyrail]

Does anyone have any experience of using a mini hot air gun on a model to bend/reshape part of a body?

I am contemplating one and wondered what the thoughts of others might be, thanks?

I recently bought a large hot air gun for multiple uses, heat shrink work and paint stripping. It may indeed be possible to bend plastic parts using a mini one but care would be needed, it is a fine balance when heating plastic between melting and getting soft. Also do not forget the possibility of toxin release if you go a little too far.

 

[PhilP]

You will find it difficult to get 'everything right' when trying to do this..

You need to balance the amount of heat being produced. The temperature, and the area being heated / volume of hot-air.

I think for most modelling work, a 'paint-stripper' size device will be too hot, and too unwieldy, to be of use?
If you get the plastic to hot, it will 'bloom' the surface, possibly start to shrink/begin to lose its form.
Getting it evenly heated (depends on size, obviously) could be a problem, and handling hot plastics / not burning yourself with the flow of hot-air.

The smallest / simplest device, would be the 'embossing guns' from the likes of Hobbycraft.
A single temperature, lowish flow device used for heating embossing powders in card-making. - About £15.00 retail (less online).

I have a hot-air reflow tool (actually part of my soldering station). These are also available separately.
This is like an embossing tool, but you have a selection of different size/shape nozzles you can fit, to help direct where the air will go.
I can also set the temperature, and independently control the rate of airflow.
This would probably do for smaller parts.

The problem is knowing the temperature for the plastics you are working with, and getting the part evenly heated.
Once it is 'soft', you will also have the danger of the surface being marked whilst handling. A very fine balance.

Possibly, curving over a former, might be a better option?
You could use a piece of pipe. Heat the plastics with a larger device, then perhaps heat the inside of the former, and let the plastic 'droop' into shape.

I would experiment with what you already have, before investing too much time and money, into this.

Do report back, it will be of interest.

PhilP.

 

[playmofire]

I've had some slight success with a multi-heat setting hairdryer.

 

[Paul M]

My No2 Child has a small hot air gun, not to dissimilar to a hair dryer, that I've borrowed a couple of times, it seems to work well, providing you heed the above advice. I'll add that plastic tends to just "go". It may take a while, but all of a sudden will melt without much warning

 

[JimmyB]

I have a "standard" hot air gun, possibly similar to that described by dunnyrail above, and is mainly used for heat shrink and paint stripping. However the over day after washing a brass model ready for painting, I used the gun on a medium setting to help dry the model, keeping the gun at a distance. However, first it melted my low temperature solder, and then proceeded to melt a white metal component. So as been mentioned, know your plastic, and ensure you can be precise in the temperature settings. Certainly a lesson learnt for me.

 

[DafyddElvy]

Having nearly melted a tram dash board when I tried to shrink some heat shrink I am more than aware of the less than fun things that can happen with a heat gun.

The reason for the use of a heat applicator coming in to my mind again is to mould the bumper to the same shape as the front of the tram. The thinking is to cut the bumper strip in the middle, place a brass former between the frame underside and simply form the bumper to the required profile. Sounds simple but based on my previous application of said tool I'm a wee bitty nervous about the damage this ham fisted modeller could cause.

The other option I have thought about was trying to hold the model over a boiling kettle, however as the last time I used thebketrle for something similar I ended up buying a new kettle, which I still sometimes get reminded of.

Think, think, think David, their has to be an easy way to do this

 

[dunnyrail]

Having nearly melted a tram dash board when I tried to shrink some heat shrink I am more than aware of the less than fun things that can happen with a heat gun.

The reason for the use of a heat applicator coming in to my mind again is to mould the bumper to the same shape as the front of the tram. The thinking is to cut the bumper strip in the middle, place a brass former between the frame underside and simply form the bumper to the required profile. Sounds simple but based on my previous application of said tool I'm a wee bitty nervous about the damage this ham fisted modeller could cause.

The other option I have thought about was trying to hold the model over a boiling kettle, however as the last time I used thebketrle for something similar I ended up buying a new kettle, which I still sometimes get reminded of.

Think, think, think David, their has to be an easy way to do this

What about trying to curve some brass or nickel silver sheet? Curve with a bit of tube over some cloth.

 

[JimmyB]

Having nearly melted a tram dash board when I tried to shrink some heat shrink I am more than aware of the less than fun things that can happen with a heat gun.

The reason for the use of a heat applicator coming in to my mind again is to mould the bumper to the same shape as the front of the tram. The thinking is to cut the bumper strip in the middle, place a brass former between the frame underside and simply form the bumper to the required profile. Sounds simple but based on my previous application of said tool I'm a wee bitty nervous about the damage this ham fisted modeller could cause.

The other option I have thought about was trying to hold the model over a boiling kettle, however as the last time I used thebketrle for something similar I ended up buying a new kettle, which I still sometimes get reminded of.

Think, think, think David, their has to be an easy way to do this

To straightened resin parts it is recommended to heat them, I do this in the oven, set to 80C, not too hot to melt, consistent temperature, and with care, no burnt fingers.

 

[Tanker man]

Recently, I replaced the roof of my Jigstones built semi, the tiles were from 3D printed sections glued together. There was a ‘tongue’ section over the two bay windows which required the roof to rais out and up slightly. I clamped the roof with wood above the tongue section and along the edge of the tongue and boiled a kettle. I used boiling water to run over where I wanted the bend and was surprised how easily it bent to exactly where I wanted it, quickly cooled with cold water, it fitted exactly……..maybe I was lucky ( or just skilled!!) .
When you think that the filament requires 200* to melt it when building it, I think the water, which must have been just off 100* by the time I used it, then you do not need excessive heat to bend it. I know you are using plastic and I was using PLA but I thought this may be helpful
Dave

 

[David1226]

Recently, I replaced the roof of my Jigstones built semi, the tiles were from 3D printed sections glued together. There was a ‘tongue’ section over the two bay windows which required the roof to rais out and up slightly. I clamped the roof with wood above the tongue section and along the edge of the tongue and boiled a kettle. I used boiling water to run over where I wanted the bend and was surprised how easily it bent to exactly where I wanted it, quickly cooled with cold water, it fitted exactly……..maybe I was lucky ( or just skilled!!) .
When you think that the filament requires 200* to melt it when building it, I think the water, which must have been just off 100* by the time I used it, then you do not need excessive heat to bend it. I know you are using plastic and I was using PLA but I thought this may be helpful
Dave

Definitely skilled.

David

 

[Greg Elmassian]

What Phil and Jimmy said, you need a controllable, constant, even heat, much lower than a heat gun.

Even then it is tricky.

One of the newer "toaster ovens" works well, as you can control the temp to 165 degrees F on up in 5 degree increments, and using the "convection fan" really keeps the temp constant inside.

Take it really slow... many people have destroyed models (including myself) going over the threshold from plaint to "holy s**t!, it wrinkled up into a ball" is really easy.

Greg