Mentor (oz4479)


Mentor (oz4479) by Ron Young from Mercury 1952 - plan thumbnail

About this Plan

Mercury Mentor. Free flight rubber model.

Direct submission to Outerzone.

Update 02/04/2021: Added kit instructions, also Mercury decal, thanks to AdrianCulf.

Quote: "INTRODUCTION: The Mentor is the first rubber model in the Mercury 'C' series of competition designs. It is an efficient lightweight model with a good compe-tition performance and is specially recommended for modellers of moderate ability wishing to get their first experience of competitive rubber flying.

Construction is very simple, the model is rugged and has pleasing functional lines.

With a fully wound motor the climb is excellent and flights of 2-1/2 to 3 minutes can be regularly obtained.

Follow the instructions for trimming and flying carefully, especially if you have not flown a rubber model before. Rubber models require more trimming than power models and you must not make the mistake of underestimating this problem.

The building sequence given will enable you to build your MENTOR accurately and in the shortest possible time.


1. Build two exactly similar sides from 1/8 sq over the plan. The nose is sheeted in with 1/8 x 3/4 strip trimmed to shape. Add the pieces of 1/8 x 3/4 for the rear motor peg and carefully drill the necessary holes for the dowel. When thoroughly set, remove from the board.

2. Join the two sides over the same drawing on the plan as you built them on. Cut all your spacers from 1/8 sq in pairs. Add nose sheeting from 1/8 x 3/4 strip. Note that there is no additional sheeting where the rear motor peg is fitted.

3. Remove fuselage from board when cement is set. Cut away top longeron at rear. Add extra piece of 1/8 sq just behind motor peg sheeting as shown on plan.

4. Cut out all printed parts for wing mount. Check how these fit together to form the cabin before attempting assembly.

5. Sheet in under windscreen position with two pieces F4. Cement pieces F3 in place.

6. Cement two halves of F1 and F2 together and cement these formers in place. (You have now completed stage 1 of this construction as shown in the detail on the plan.)

7. Cement 1/8 dowel to piece of 1/8" sq balsa to form detail 'A'. Cement in place to formers F1, F2 and upper longeron. (This completes stage 2.)

8. Join the two halves of F5 together and cement in place onto F1, F2 and dowel. Cement cabin walls F6 and F7 in place. Add piece of 1/8 sq to form front cabin windscreen support..."

Supplementary file notes

Printwood formers.


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Mentor (oz4479) by Ron Young from Mercury 1952 - model pic

  • (oz4479)
    by Ron Young
    from Mercury
    36in span
    Rubber F/F Kit
    clean :)
    all formers complete :)
  • Submitted: 27/05/2013
    Filesize: 630KB
    Format: • PDFbitmap
    Credit*: vintage1, AdrianCulf

Mentor (oz4479) by Ron Young from Mercury 1952 - pic 003.jpg
Mentor (oz4479) by Ron Young from Mercury 1952 - pic 004.jpg
Mentor (oz4479) by Ron Young from Mercury 1952 - pic 005.jpg

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User comments

Photo of the completed Mentor model is a screengrab fom Youtube video posted by wonderfulcat found online at
SteveWMD - 30/05/2013
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Download File(s):
  • Mentor (oz4479)
  • Plan File Filesize: 630KB Filename: Mentor_Mercury_oz4479.pdf
  • Supplement Filesize: 97KB Filename: Mentor_Mercury_oz4479_decal.pdf
  • Supplement Filesize: 3534KB Filename: Mentor_Mercury_oz4479_instructions.pdf
  • Supplement Filesize: 31KB Filename: Mentor_Mercury_oz4479_printwood.pdf
  • help with downloads


* Credit field

The Credit field in the Outerzone database is designed to recognise and credit the hard work done in scanning and digitally cleaning these vintage and old timer model aircraft plans to get them into a usable format. Currently, it is also used to credit people simply for uploading the plan to a forum on the internet. Which is not quite the same thing. This will change soon. Probably.


This model plan (like all plans on Outerzone) is supposedly scaled correctly and supposedly will print out nicely at the right size. But that doesn't always happen. If you are about to start building a model plane using this free plan, you are strongly advised to check the scaling very, very carefully before cutting any balsa wood.


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