Cutting out molded windshields in kits. HELP!

[Mr. Paxton]

I build 1/43 scale Indy kits from several manufacturers.
I consistently screw up while cutting out the windshields. 

I can't see the molded cut lines very well and cutting with an ex-acto always seems to slip.

I need help! Tips?? Tired of having to contact manufacturers and beg for replacements!!

[ampersand]

I must have cut hundreds of vac-form windscreens when I built Ampersand models for a living, and even with all that practice I still make a mess of it from time to time! My best advice is that you need three things: two X-acto knives (or another form of scalpels with a pointed blade) and a whole lot of patience.

I use two knives, one with a not-so-sharp blade and one with a very sharp blade. With the sharp blade I carefully trim the edge of the vac-form where the windscreen meets the body. Then I use the blunt knife to "stab" through the top of the vac-form and use it for holding it down to the body to see where additional trimming is required. Once I am satisfied with the edge which is to be glued to the body I carefully cut away the vac-form top by placing the blade snug against the top and cutting sideways, holding the vac-form upside down against a hard surface, i.e. the workbench. This is where I usually mess up, so this is where the patience comes in!

Once the top is cut away I glue the windscreen in place using a canopy glue which dries up clear and fills out any nooks and crannies that may have occurred. After the glue has hardened I then very carefully trim the top edge of the windscreen with the sharp blade.

I hope this makes sense - if not, maybe I should make a You Tube tutorial!

Bo

[Mr. Paxton]

thanks for the tips Bo.
I am cutting one out again tonight so I will try your suggestions.

[robh]

Here is my alternative method (and I readily admit that I have less experience than Ampersand):

While wearing 3.5 power reading glasses, I use thin strips of masking tape to outline the outer edges of the windshield. I then use sharp cuticle scissors to cut away the excess material along what will be the lower edge of the windshield. I cut a little bit outside of the masking tape outline and then use a 2 sided foam sanding pad to sand down to the final edge starting with the coarse side of the pad first and finishing the final edge with the fine grit side of the pad. Please note: Don't rely on the molded edges of the windshield to accurately match the windshield outlines of the body and constantly test fit as you remove material. I then repeat the process to cut out the upper and rear edges of the windshield. I have found it useful to stuff the inner cavity of the windshield molding with Blue Tac/Silly Putty or similar when removing material for the upper and rear edges as it makes the windshield molding less flimsy and easier to handle as you remove more and more material. I have also had success by attaching really ill fitting windshields with super glue (dip the windshield in Future 1st or the glue will fog the windshield), fairing them in with Mr. Surfacer 1000 or 1200, sanding out the seams, polishing to restore clarity,and masking off before painting the body. I also make duplicates of the kit windshields with plaster of paris molds and an old Mattel vacuform machine as I have yet to have any 1/43 kit manufacturer even respond to a request for replacement parts.

[hurtubise56]

I second the cuticle scissors & sanding to fine-tune, but I have to wear 4.0 power glasses and also sometimes use a magnifying light! What Rob said about the lines is true, treat them as an approximation only.

Brian

[ampersand]

I had never thought to use sanding as a means to remove material from vac forms - just goes to show that you can still learn new tricks even after 40 years of building! I'll have to give that a try, it sounds like a great method. Rob, I am curious about your use of super glue - I take it that you dip the windshield in Future after you have trimmed it to fit so that all surfaces are protected?

[robh]

yes, you need to dip the windshield in Future after you trim it to fit, but before you apply super glue. Non-fogging super glues are available, but they are expensive and have short shelf lives.

[johnwebster]

G&S Hypo Cement for watch crystals dries clear and doesn't fog.

[Mr. Paxton]

Update: I ended up using a combination of the above suggestions.
I actually filled the windscreen cavity with modelling clay which made it MUCH easier to hold the piece in place and made a much easier job of it. Because my eyes aren't as good as they used to be, i am going to mask off my lines next time, although I did have great success without the masking.

Just to be clear, I am not concerned with mounting it, although I appreciate the insights. I have always used canopy glue and have had 100% success.
I'll let everyone know how the next one goes!