Sperry Monoplane (oz10818)

 

Sperry Monoplane (oz10818) by Peter Rake 2013 - plan thumbnail

About this Plan

Sperry Monoplane. Scale model for micro-RC using a PZ brick or similar setup.

See RCGroups build thread by BlazingStar at: https://www.rcgroups.com/forums/showthread.php?2097479-Peter-Rake-18-Sperry-Monoplane

Note this plan was released into the public domain by Peter Rake, posted online at rcgroups.com/forums/showp... in September 2014.

Update 22/10/2023: Added article, thanks to hlsat.

Quote: "Peter Rake presents his pint-size Sperry Monoplane, with fullsize pull-out centre spread plans.

Since the little Eastbourne Monoplane (oz10661) feature from a few months back proved so popular, I've decided to treat you all to a similar sort of column. Instead of my usual waffle, this month's column will just be a construction article to go with the first part of the full size plan that appears elsewhere in this issue. Good or what? Not only do you get to see me writing my own column, you get a free plan to boot.

The model: Once again this is a scaled down version of an already successful design. This one, however, is intended to use a Vapor receiver 'brick', brushed motor and single cell LiPo. The plan shows a Nine Eagles motor unit, which is pretty much like many of the Parkzone units. It also shows an alternative motor plate (MM) to suit the motor I actually used in the prototype model - an AEO 7 mm unit. This proved adequate for my model, so if you opt for the larger motor you'll have no problems with regards sufficient power.

One thing that you will notice in the photos is that I used some 1/32 ribs in my wings, but the plan shows all 1/16 ribs. Similarly, my model has balsa trailing edges, but the plan shows bass. The reason for these changes is that as the tissue shrunk, my original wings buckled quite badly. They didn't just warp; they almost destroyed themselves. Ribs buckled and trailing edges actually broke in places.

Because I can't specify very hard balsa for the laser cut parts, the publisher will doubtless offer, bass is a good option for trailing edges and the thicker ribs should make your life easier all round.

At just 18 inch wingspan, you are going to need to keep the model light. Even with the replacement trailing edges (from the hardest balsa I could lay my hands on) and heavily repaired ribs, my model came out at a respectable 35.5 grams ready to fly.

Let's get building: As you can see, there really is nothing particularly complicated about the build, so I won't bore you with a 'stick A to B' style article. I'll run briefly through how the model goes together, just explaining anything I feel needs more information.

There's nothing unusual about the basic assembly. It's the usual build-over-the-plan sort of affair. You make two fuselage side frames, mark former and receiver mount positions on them and join with formers, MM and cross braces. I built in the centre section (c/s) struts as I built the side frames, but they could just as well be fitted after the sides are joined.

Worth noting here is the need to use fairly soft 1/32 sheet for the rear decking. Not only is it lighter, it will also be easier to curve over the formers without distorting the rear fuselage.

The main undercarriage (u/c) is assembled as two-ply structures, which are assembled over the plan and glued into the slots in formers F2 and F3. Since the area between these two formers is filled with 1/32 balsa, you'll also need to trim slots in that to clear the u/c legs. l like to cover this area before gluing the u/c in place; s just so much easier that way. There's absolutely nothing at all funny about trying to tissue cover around an u/c firmly glued into your fuselage.

If, like me, you opt for the AEO motor (they're cheap, and I'm very fond of cheap), position MM (the alternative one) so your prop is in the right place and glue the motor into the former. Set up thrust lines to match those shown on the plan.

After a little sanding, you'll have a completed fuselage, so now I suppose we'd better build some bits to hang onto it.

The hardest part of the tail surfaces is laminating the outlines. I like to use depron forms, pinned to the board. Then the soaked and glued strips can be held in place around them using scraps of balsa to hold them snug against the forms. Some people like use a pin 'fence' to shape around, but I find that tends to crease the wood.

Once the outlines are completely set, pin them over the plan and stick in all the little bits of balsa that are supposed to fill the gap. I usually sand then as complete tailplane/elevator and fin/rudder units before separating them. Be careful just how much you sand them. It's surprising how quickly your 1/16 tail surfaces can become 1/32 tail surfaces.

Although you can just make out some experimental fishing line hinges in the photo, I decided that wasn't very practical. I ended up using narrow strips of scuffed up floppy disc material for the hinges. I just found it a lot easier to work with than fishing line I could barely see half the time.

Okay, I can see I've run out of space again - the hazard of including a plan in the column, but we will finish this off next time. Then we'll finish building the model and take a look at tissue covering..."

Update 30/10/2023: Added article (part 2) thanks to hlsat.

Supplementary file notes

Article (parts 1 and 2).

Corrections?

Did we get something wrong with these details about this plan (especially the datafile)? That happens sometimes. You can help us fix it.
Add a correction

Sperry Monoplane (oz10818) by Peter Rake 2013 - model pic

Datafile:

ScaleType:
  • Curtiss_JN-4 | help
    see Wikipedia | search Outerzone
    ------------
    Test link:
    search RCLibrary 3views (opens in new window)


    ScaleType: This (oz10818) is a scale plan. Where possible we link scale plans to Wikipedia, using a text string called ScaleType.

    If we got this right, you now have a couple of direct links (above) to 1. see the Wikipedia page, and 2. search Oz for more plans of this type. If we didn't, then see below.


    Notes:
    ScaleType is formed from the last part of the Wikipedia page address, which here is https://en.wikipedia.org/wiki/Curtiss_JN-4
    Wikipedia page addresses may well change over time.
    For more obscure types, there currently will be no Wiki page found. We tag these cases as ScaleType = NotFound. These will change over time.
    Corrections? Use the correction form to tell us the new/better ScaleType link we should be using. Thanks.

Sperry Monoplane (oz10818) by Peter Rake 2013 - pic 003.jpg
003.jpg
Sperry Monoplane (oz10818) by Peter Rake 2013 - pic 004.jpg
004.jpg
Sperry Monoplane (oz10818) by Peter Rake 2013 - pic 005.jpg
005.jpg

Do you have a photo you'd like to submit for this page? Then email admin@outerzone.co.uk

User comments

I see a model flying, but there's no one in the cockpit. Could the pilot be Mr Rake's ghost?
"...but know, thou noble youth,
The serpent that did sting thy father's life
Has his faith broken, and ran
Aback to castor oil dispensing.
O, horrible! O, horrible! most horrible!"

Miguel - 02/11/2023
Add a comment

 

 
 

Download File(s):
  • Sperry Monoplane (oz10818)
  • Plan File Filesize: 108KB Filename: Sperry_Monoplane_18in_oz10818.pdf
  • Supplement Filesize: 832KB Filename: Sperry_Monoplane_18in_oz10818_article_1.pdf
  • Supplement Filesize: 814KB Filename: Sperry_Monoplane_18in_oz10818_article_2.pdf
  • help with downloads
 

Notes

* 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.

Scaling

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.

 

Terms of Use

© Outerzone, 2011-2024.

All content is free to download for personal use.

For non-personal use and/or publication: plans, photos, excerpts, links etc may be used, provided that full and clear credit is given to Outerzone with appropriate and specific direction to the original content i.e. a direct hyperlink back to the Outerzone source page.

Unauthorized use and/or duplication of this material without express and written permission from this site's owner is strictly prohibited. If we discover that content is being stolen, we will consider filing a formal DMCA notice.