Filling and Sanding, Without Sandpaper!

Tools 'n' Tips Article by Will Hendriks

Work in a well-ventilated area!

 

Photos By Steve Bamford

Applying model putty to fill seams and gaps, and then sanding and filing to shape is one of the most difficult aspects of scale model building.  Often, this process is messy, time consuming, and damages surrounding surface detail. Results can be frustrating and discouraging.
 
Here is a process that I have found to be consistently successful for certain filling applications.  It involves the use of readily available Toluene based fillers such as Squadron White putty and Green Putty. Also required are normal strength nail polish remover, and a few simple tools, as shown.
Work in a well-ventilated area!

Here's the offending wing root seam gap on our example......Hasegawa's 1/48th P-38J Lightning.

 

Basically, one masks off the areas to be filled. This step prevents
errant filler from "etching" into the surrounding plastic. 
Filler is applied to our high-tech putty knife.....a toothpick. 
The filler is applied to the masked areas, in this case the lower outer
wing panel/boom joint.
Filler is now fully applied.
The masking tape is then removed.
Now comes the secret part: moisten a Q-tip, cotton ball, or a bit of cotton cloth with normal strength nail polish remover.

 

 

Now with the moistened Q-tip, smooth and blend the filled areas and remove excess filler. Best results are obtained just as the filler begins to dry. The beauty is that the filler can be smoothed perfectly flush with the surrounding surfaces, without harming the plastic or
raised detail. If filler gets into scribed surfaces, just remove it with a wooden toothpick, moistened in the nail polish remover. Clean up residue with a cotton cloth. Repeat if necessary.

 

There! Clean, blemish-free filled gaps in less than five minutes!  I usually let the filled surfaces dry several hours before painting. 

This technique is a revolutionary way to apply filler, but without the need for sanding or filing! It has the added benefit of preserving detail, which would otherwise be destroyed by filing and sanding, while dramatically speeding up the process. The best application I can think of is filling wing root gaps. It also works very well in hard to reach areas, such as wheel wells and bomb bays. The technique also preserves raised detail on older kits, such as the Monogram classics. Best of all, it is quick, clean, and easy!

Before and after....This is the wheel bay of the 1/48 Hasegawa P-38.  Will quickly did this technique in under 3 minutes to this wheel well to give you an idea of the difficult areas this filler trick could be really helpful.  Obviously this particular filling job isn't complete....this is more of a rough example of the types of places this trick would be the most help.
Before After

Disclaimer:  The active ingredient in nail polish remover is acetone: IMPORTANT: DO NOT use full strength acetone, as this will severely damage the styrene surfaces. Nail polish remover is an emulsion of acetone and water, and various girly oils and essences... Also do not use the "Environmentally Friendly" acetone-free substitutes; they just don't work! Normal strength nail polish remover (such as Cutex) will not harm styrene or resin: if you are unsure, try it on a scrap piece first.  It will, however, strip paint, so be careful.  

Work in a well-ventilated area!

Will Hendriks

Does this work with autobody finishing filler?

My filler of choice is automotive autobody finishing filler (comes in 1 pound/.5kg tubes).  Automotive autobody finishing filler smells like it is lacquer based.  So, I tried Will's above technique and it works fine with the autobody finishing filler I prefer to use, so this new technique will be one I will use to a great degree.    Steve Bamford

 

Additional info;

Denatured alcohol will also work for this method.  While still nasty stuff, denatured alcohol isn't quite as virulent as acetone.  Dave Lake

If you'd like to use this article in a monthly club newsletter etc....all I ask is you e-mail Will Hendriks for permission and give credit and URL for Aircraft Resource Center.

Photos and text by Will Hendriks and Steve Bamford