Masking round windows

I just completed some WW2 bombers that had oblong and round observation windows.  I do not have the skills that some people do to cut perfectly circular masks from tape or frisket.  So what I do is use white glue barely thinned with just a couple drops of water and a drop of dishwashing soap.  I blob it on using a fine paint brush and, if needed, I use a toothpick to push the glue into the odd or narrow corners.  I then paint to my heart's delight and when I'm done, I just use a toothpick to pop the glue masks off.  I also use this technique to mask off those canopies with lots of framing like on the B-36, P-61, Avengers, etc.

Hope that helps!

Eric

Airfix Hemper wrote:

Do any of you aircraft builders out there have a suggestion for masking round windows?  I have yet to come up with a totally satisfactory way to mask round windows or hubs on landing gear.  I have a plastic template with various sizes of circles and use Excel or other blades to cut tape but it is hard to get a perfect circle, especially for smaller windows or hubs.  I have tried to substitute Kristal Kleer for the plastic in really small windows and have a dental dam punch for very small holes but wonder if anyone makes any kind of punch that gives you several size alternatives and works on Tamiya or other brands of masking tape.   Any suggestions would be much appreciated.

A punch and die set. Waldron used to make these, but the manufacturer has since retired, although I believe some retailers on the net still carry them. There are equivalent sets out there if you can't find the Waldrons.

The Waldron miniature punch & die set is available from Roll Models.  They took over the manufacture from Waldron.

MicroMark makes a fairly inexpensive punch & die set with punches ranging from 1/16 inch to about 1/4.

HarborFreight Tools offers a larger punch & die set (think Wadron on steroids)  with punches ranging from 1/8 to 3/4 inch.

I have both the MicroMark and HarborFreight sets and have many uses for them, from punching masks to punching structural round shapes in styrene or light brass sheet 

Wow, that sounds like a great idea for the round windows.  I actually tried that on a helicopter model a few years ago and it worked really well.  I forgot about that until now.

 I ended up e-mailing Mark Hembree who suggested some punch and die sets from Micro Mark.  I went ahead and ordered these so we'll see how they work out.  But I may end up using the white glue suggestion.  Many thanks for responding!!

Yes, thanks again to all of you!  The liquid masking and white glue masking ideas may come in very handy in case the masks I cut are not quite the right size.  I have already glued the windows in place with CYA and have sanded them flush with the fuselage so there is no recess or area to catch any excess mask but I can use either the glue drop idea or my liquid mask to fill in any discrepancy.  I will end up polishing the windows with 2000 grit and finer sanding papers and films, will polish with toothpaste and then Bare Metal Foil plastic polish, and will probably finalize with a coat of Future, in case any of you were wondering.  Then I will place my masks over the window, supplement as necessary with liquid masking agent as mentioned above, then will probably repolish and re-Future when I take the bandages off.  Voila, I hope to have some very spiffy windows on a rare British glider!   Unfortunately it is an old Frog kit, not Airfix......

 I must also apologize for taking so long to check back with the forum - I have had a busy week here at work and got sidetracked.  Anyway, happy Thanksgiving to all of you.