Multi colour covering

[Ace]

Looking to cover a model with more than one colour on each main component and looking for tips on how to achieve this on an open structure airframe?

Where sheet I can either cut the film with a 6mm/1/4" overlap, or carefully lay one over the other as you can exclude the air both with the iron and a cloth then pin prick any bubbles left.

However on an open structure the unsupported film has no support and flexes when I try to lay one on the other trapping a lot of air. Trying to join a 6mm/1/4" overlap in these unsupported areas has been unsuccessful. I have seen others, Ron's Racal/Peggy Sue for instance where a transparent insert is joined to a solid cover. Is a pattern cut and joined flat with an iron before applying to the airframe, or by some other method?

How do others make multi coloured airframes?    

 

Edited July 30, 2021 by Ace

[kc]

The video by Solarfilm inventor Derek Hardman covers all the best methods = well worth watching when you have an hour and half spare.

[Ace]

Agreed it's excellent however it only shows colour joins on solid surfaces/spars or the use of Solartrim which is of course self adhesive. Ideally hoping to be able to two tone wings/fuz using just heat shrink film with curves or joins that were not supported on their rear. Is there another technique other than shape and pre join before applying ? 

[Engine Doctor]

Ideally any joins need a landing to support them. The land only has to be 1/4'inch wide. This gives support to edge allowing the second piece to be ironed onto the first. Could you not cover the whole model in the base colour , possibly white then add other coloured panels over this?

[Ace]

Thanks ED.

Sheet or stringers - yes, whole overlay - possibly but large areas of trapped air bubbles on unsupported film is a real time consuming issue to try and deal with which never appears acceptable.

Idea is for a mix of solid and translucent on an old style open stick fuz/wing  with no sheeted LE and mostly open fuz on something like this.

 

[John Lee]

For my Weisels I used self adhesive vinyl over the base colour. Applied using the soapy water method it avoids the trapped air bubbles and you can reposition to your heart's content. Whilst not as malleable as the dedicated films it can be persuaded around curves with a heat gun. At £3 a meter pretty economical too. I used these people, but no doubt there is plenty of choice in this field.

 

[Ron Gray]

They way I did it on both the Rascal and Peggy Sue was to cut the opening in the solid (in my case white) top covering then cut the transparent panel approximately ½” oversize. To overcome the unsupported edge where the transparent infill spanned longerons I inserted some 1/8” square balsa infill pieces to give it a solid edge.

[Ace]

Thanks guys for your experiences, appreciated ?

Re-think on using straight lines, extra planning/support or large areas of self adhesive trim ?

[Trevor]

I was faced with a similar issue when covering the Aeromaster shown in my Avatar. There’s a brief description of the method used about three quarters of the way down this page: http://www.bartonhewsons.uk/home/modelflying/sport/aeromasterdiary2.html

[Allan Bennett]

Have you thought about painting the second colour on?

[Ace]

Trevor - Nice job ?   I have a wheeled pecker and can certainly relate to the uncomfortable feeling of puncturing taught film but it does work well in reducing trapped air, although never tried it on unsupported film. Solid over a translucent should work but trans over trans might not look that appealing.

 

Allan - no I hadn't so a good point, although I am experimenting with painting laminating film so technique would transfer.

 

Originally thought I wanted a two tone translucent, after all who would want to hide any lovely open framework. Unfortunately practicalities are dictating either a colour change only where supported so additional balsa by need to be incorporated, or consider a solid/trans where film/paint or vinyl for the solid.

 

Thanks again all - I feel a reevaluation over tea and bickies is needed ⚖️