Vacuform Basics

Cutting out the parts
The next stage stage is to carefully run a new blade around the the outline of the parts. Don't try to cut right through - there's no need and you'll probably just mess things up if you try; just score gently with a number of light strokes.

Obviously, the closer you cut to the parts, the less spare plastic you'll need to get rid of later. One neat trick to reduce the clean-up is to score around the parts at an angle of about 45%. Also, for complex shapes I normally run a few extra score-marks out to the edge of the sheet so it's easier to work on tight areas.

Now for the moment of truth! Once you've scored right around the part, gently flex the styrene sheet. As you flex it, the part will begin to separate from the sheet - don't rush it, but the plastic will split accurately along your score-marks and the parts will drop free. Once the parts are removed from the sheet, the purpose of earlier ink/paint stage is obvious - all the excess is highlighted as bare plastic.

The parts will be moulded with any windows and cockpit cutouts solid - whatever you do, don't be tempted to open these up yet, because they help maintain the rigidity of the parts, which helps you sand them accurately.

Sanding & trimming
There's no escaping this stage... but it really isn't as tedious as many would have you believe. Some modellers like to work on a flat surface, other's prefer to hold the parts and use a tool like Handvik Handy Sander or wet 'n dry paper attached to a piece of tile (as in the photos) - either way, work steadily and sand the parts with a "figure of eight" technique. Check your progress frequently to make sure you don't sand away too much. On large parts try to maintain an even pressure across the surface and shift your grip regularly to avoid "pressure points".
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About the Author

About Rowan Baylis (Merlin)

I've been modelling for about 40 years, on and off. While I'm happy to build anything, my interests lie primarily in 1/48 scale aircraft. I mostly concentrate on WW2 subjects, although I'm also interested in WW1, Golden Age aviation and the early Jet Age - and have even been known to build the occas...


Very nice article Merlin !! You explained it very well. After reading your article, I would like to try to do a vac model myself. What would be a good starter kit, or do vac's basicly have the same difficulty ??
AUG 23, 2005 - 11:01 PM
Thanks for that Rowan. Like so many I never realy considered Vacform kits, untill I won one in Costas's free draw give away. This is a great help seeing as I'm a total Facvorm virgin. looking forward to further instalments. Good idea Dave, I'm in on that. Maybe an informal on-line group build? Not sure if we would find 10 people with a vacform kit... . Cheers Henk
AUG 23, 2005 - 11:13 PM
Great Feature article, Rowan! I personally have messed a little with vacu-form while building the wood and paper airbirds, but have never tried to tackle a complete vac kit...your tips and technique just may prompt me to do so! Thanks for the time and effort to put something like this together, sir... Gunny
AUG 23, 2005 - 11:13 PM
Very good and very usefull! Tanks for sharing! Cheers and happy modelling! Prato
AUG 24, 2005 - 02:25 AM
I'd join in too! I have a TSR2 and a BAE Nimrod MR2 to build, but have shied away from them.
AUG 24, 2005 - 02:48 AM
Hi all Well, I guess I'd obviously have to join in! :-) I've got quite a few stashed away, so I'd be spoilt for choice. Hi mossieram No, the difficulty can vary greatly. Depending what type of aircraft you're interested in, it'd be worth you checking out the models produced by Aeroclub, Dynavector, Koster and Sierra Scale - there are plenty of others, but those four are good for starters. Sierra Scale's Consolidated P-30 and Fairchild PT-19 were the subjects of the first two reviews I wrote for Armorama. The model I'm building is Koster's Martin Maryland - a neat kit, but probably a bit ambitious for a first vacuform kit. All the best Rowan
AUG 24, 2005 - 03:18 AM
Rowan: Thanks for the article !!!! Very informative & filled in at least one question I had (angle of blade when scoring). I bought my first vacuform kit at the IPMS Nats -- the Sierra 1/48 P-30 / PB-2A. I wanted something "easy" (no big complex things) and yet something I hadn't done in plastic and something of interest to me. I'm very pleased with the kit (great scale drawings to help with adding detail), but had only gotten around to the marker step, although not as neat & complete as you describe, so tomorrow I'll be sure to get in the cracks & crevasses. If we're going to do a vac-GB, then I could be in with this kit, but I'd like to see a schedule for the GB, as I really want to get started on this. Again, great article & looking for follow-ons. John
AUG 24, 2005 - 01:15 PM
A big help for people taking that first deep breath before the plunge in to the alternative world of Vacs. And I notice its quite an old feature....I was a lot younger when this first ran on site, (not quite short pants). So its a good idea its given an airing as the subject of Vacs seems to be cropping up more often recently. Great job Rowan....any sequal(s) planned? Cheers Peter
JUN 04, 2008 - 12:50 AM
Very good ... How about a little more advanced methods like building the bulkheads and such. is there info on that too. Thanks, Kelly
JUN 10, 2008 - 08:34 AM
I'm with kelly on that one . More detail on bulkheads , and attaching the wings ?
JUN 10, 2008 - 11:16 AM