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Old Jul 02, 2014, 06:23 AM
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Australia, NSW, Hornsby
Joined Jul 2005
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Lost foam 51

With Manilla Slope Fest only 10 weeks away & having nothing to take, I've decided to make life a little bit harder & scratch build a P51.
Originally I was planning to build from one of Paul Janssen's plans & an Andy Blackburn Jet Provost but unfortunately Paul is moving & not selling plans at the moment & the Provost plan still hasn't arrived from Traplet.

Never mind, I have his 36" P51 plan from QFI here (balsa over foam) & I've had it enlarged to 60"
My plan is to use glass over a lost foam plug as per many of Paul's plans & have a crack at cutting my own wings which I haven't done in 20 or more years (& that wasn't exactly a raging success).

Some progress pics to follow.

Al
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Old Jul 02, 2014, 11:05 AM
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United States, MA, East Longmeadow
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looks great! thanks for posting.
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Old Jul 02, 2014, 11:52 AM
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United Kingdom, England, Hitchin
Joined Jan 2004
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Quote:
Originally Posted by _AL_ View Post
With Manilla Slope Fest only 10 weeks away & having nothing to take, I've decided to make life a little bit harder & scratch build a P51.
Originally I was planning to build from one of Paul Janssen's plans & an Andy Blackburn Jet Provost but unfortunately Paul is moving & not selling plans at the moment & the Provost plan still hasn't arrived from Traplet.

Never mind, I have his 36" P51 plan from QFI here (balsa over foam) & I've had it enlarged to 60"
My plan is to use glass over a lost foam plug as per many of Paul's plans & have a crack at cutting my own wings which I haven't done in 20 or more years (& that wasn't exactly a raging success).

Some progress pics to follow.

Al
The Janssens models are absolutely great - I've never seen one that flew badly, and they fly in a good range of conditions too. One of my prized possesions is his original Macchi 202 prototype; it's a little battered now after 20+ years and ~5 owners, but still flies as good as new! I also have a Spit Mk24 fuselage tucked away in the loft too, though that may now get an electric powertrain in the end if I ever get round to building it.



Star, Hawk and Macchi over Cilan (4 min 11 sec)


Although not all of the plans are available from Traplet, quite a few are, including the P51...

Best of luck with your build!
Matt
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Old Jul 02, 2014, 03:21 PM
Crikey never leave beer behind
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Mt Annan Sydney Australia
Joined Dec 2003
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I'm watching Al if you need a hand give me a shout
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Old Jul 02, 2014, 09:01 PM
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Carlsbad, CA
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Nice build. I've thought about building a lost foam model myself. Have not done much more than think about it so far.
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Old Jul 03, 2014, 06:57 AM
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Australia, NSW, Hornsby
Joined Jul 2005
772 Posts
Cheers.
Matt, I love that Macchi. A really nice looking model. I had seen pics but not the vid before. Looks like it flies really well.
I've got his Dewoitine 520 & P47 plans but as with most of his plans they are only around 1-1.2m & I really wanted something around the 1.5-2m mark & this one just sort of fit first go at 1.5m.

Steve, I appreciate the offer. Hopefully I won't need to take you up on it
I can't tell you how much I'm looking forward to Manilla. I really miss my slope soaring.

A long day today so not much time on the P51.
I've realized the Oil cooler on this plan is a bit of a compromise due to the original building method but it doesn't really look right. It's too narrow at the rear & looks stuck on rather than blended into the Fus so I'll have to draw up a new one that looks more scale & cut it on the weekend.
I cut the wing section out of the Fus tonight but left the camera in the shed so no pics.
My cuts are getting neater & I think I'm starting to get a feel for temp & speed with the bow.

I bought the parts for an automatic cutting jig from the Nov 2008 RC Soaring Digest. My new bows are from the same article & are much nicer than my previous one so I'll knock this together & see how it goes..
http://www.rcsoaringdigest.com/pdfs/...SD-2008-11.pdf
Page 102 from memory.

The weekend will be cleaning the shed & clear the bench so I can cut the wing cores next week.
With a bit of luck I'll have the Jig made, new oil cooler cut/ glued on & start sanding it all to shape by Sunday night.
If I can get that done, I should have a Fiberglass Fus & wing core by next weekend.
Sounds good on paper.....

Al
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Old Jul 05, 2014, 06:08 AM
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Shed cleaner what it was (certainly not "clean"), Bench cleared & wing cutting arm finished.
Even had time to build some family brownie points.
Target achieved for a change.

I was planning for a quick fly tomorrow morning at the club & then home for more building but the wind is predicted 20kt so I might shoot down to Narrabeen to a little slope that faces West & throw something off.

If I can get the oilcooler sorted tomorrow I'll be happy as I can sand to shape through the week.
I should have my wing foam Tues or Wednesday so some fun to come next week.

Al
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Old Jul 06, 2014, 05:42 AM
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Less than 10 weeks to go.....

I managed to get some flying in this morning & just cut a new oil cooler tonight.
It's the same side profile as the original plan but full width so it'll sand to shape with the Fuselage & look a bit more realistic.

Lots of sanding & hopefully a wing core to come over the next week.


Al
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Old Jul 06, 2014, 06:04 AM
Crikey never leave beer behind
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Mt Annan Sydney Australia
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looking good Al
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Old Jul 08, 2014, 07:14 AM
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Cheers.
There's something strangely therapeutic about sanding a block of foam to shape......

40 minutes with a sheet of 80 & 240 grit & it's starting to look sort of like a Mustang.
I learned 2 things tonight.
1. It would be really easy to sand too much, screw it up & have to start again.
2. Having done this once now & knowing how best to tackle it, I think I could get the next one from beginning to this stage in around 4 hours, possibly less. If the rest of the build goes well I may not only finish this in time, but may get a 2nd done.

I'm still not entirely happy with the nose section, especially the duct under the spinner. I'll sleep on it & have another look tomorrow night.

I picked up some XPS foam today for the wings but no luck locally getting Formica for templates. I've got some 2mm ply here so may have to use that.

9 1/2 weeks & counting.....

Al
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Old Jul 08, 2014, 08:48 AM
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Al, that looks great! keep up the good work!
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Old Jul 08, 2014, 06:49 PM
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Sydney Australia
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If you need some formica, just go to your local Bunnings and in the flooring section they have samples in I think 360mm*200mm sizes for a dollar or two. Lots of colours to choose from also....
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Old Jul 08, 2014, 11:28 PM
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Very Nice...
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