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Speed,Combat,Scale,Racing => Speed Talk => Topic started by: Paul Smith on March 18, 2017, 02:11:01 PM

Title: My second Perky
Post by: Paul Smith on March 18, 2017, 02:11:01 PM
I put together my first Perky in about three weeks and it lasted me 12, maybe 13 years. 
I've broken ground on a replacement. 
Second verse, pretty much like the first.

I use a wood pan type of construction.  The original has held together OK with three 4/40 bolts.  The new one will have two 3 mm bolts.  I've gone metric via Bob Hornberger (father of State Rep Pam) of Metrics Unlimited.

Step One is crudeing it in like a Viking ship.
Title: Re: My second Perky
Post by: Paul Smith on March 18, 2017, 02:12:33 PM
Step Two is to go out the frozen barn and run it by the belt sander.

As you might notice, some old aluminum engine mounts have been buried to give the engine something to sit upon.

The Wheel weaves as The Wheel wills
And none can see the pattern until it is done.
The lives of men and the live of nations,,,

,,,oh well, you all know this.
Title: Re: My second Perky
Post by: Motorman on March 18, 2017, 07:20:13 PM
blank
Title: Re: My second Perky
Post by: Avaiojet on March 18, 2017, 08:02:32 PM
Paul,

Nice planking.  ;D

CB
Title: Re: My second Perky
Post by: Paul Smith on March 19, 2017, 04:52:31 AM
Big ribs?  Sure.

I layed up the wing from scrap wood and plan to sand it to shape on the belt sander, much as you would with one big piece if 1/2" balsa, but a little lighter and MUCH less expensive.

Since the ribs will be sanded down thin, I made them wide so as to hold the LE & TE together.  Also, I made them even thicker on the outboard side, since I'll be adding even more tip weight.

The other photo was the top of my first Perky during a rehab.  The principle will be the same on this model.
Title: Re: My second Perky
Post by: C.T. Schaefer on March 19, 2017, 07:21:39 AM
Lookin' good Paul!  There are a couple new ones taking shape in N.J. too.
Title: Re: My second Perky
Post by: bob whitney on March 19, 2017, 12:10:42 PM
Florida also y1
Title: Re: My second Perky
Post by: john e. holliday on March 19, 2017, 02:58:01 PM
Why not leave out board solid and save tip weight?   I need to start on my Perky if I can find where I misplaced them.  Have a Cox that should work.
Title: Re: My second Perky
Post by: Paul Smith on March 19, 2017, 06:00:01 PM
That's a thought.  I did go somewhat heavier on the outboard.  But lead nearer the tip has more leverage that wood near the body. 

It only has 9" of wing on each side.  With the pointy tips, you can't get the weight much more than 8" out, so it takes a fair bit to keep it from torquing in.

The leadout guide has a similar issue.  You can only get it about 8" inside the CL and it needs to be ahead of the LE for best results.
Title: Re: My second Perky
Post by: Lyle Spiegel on March 19, 2017, 06:03:10 PM
I assume the new Perkys are scratch built, or does Blackhawk new owner still offer kits?
Title: Re: My second Perky
Post by: Paul Smith on March 19, 2017, 07:31:48 PM
Mine are built from plans.
The Black Hawk Perky was rather popular.  You might find one on the aftermarket.
Here is the plan.  
With an 18" wingspan as a  guide you can get it printed to size.
There's a lot left to the imagination, including the bellcrank & leadouts.
People respected Jim Walker's lawyers.
Title: Re: My second Perky
Post by: Paul Smith on March 22, 2017, 05:02:57 PM
Let me think about this step-by-step:

1. Chose the engine.
2. Bottom
3. Landing gear.
4. Wing
5. Top
6. Tailplane.
7. Flight controls.
8. Fuel tank.
9. Final assembly
10. Paint
11. FLY

Title: Re: My second Perky
Post by: Paul Smith on March 22, 2017, 05:05:40 PM
After a few passes of the sander...
Title: Re: My second Perky
Post by: Paul Smith on March 23, 2017, 07:40:25 PM
Some of the rough edges smoothed-out and carbon veil applied.
Title: Re: My second Perky
Post by: bill bischoff on March 27, 2017, 06:17:28 AM
Aren't the wide ribs on the inboard side?
Title: Re: My second Perky
Post by: Paul Smith on March 27, 2017, 08:17:00 AM
Huh?   Maybe I test-fit it backwards.
Title: Re: My second Perky
Post by: Paul Smith on April 01, 2017, 05:37:13 PM
Perky progress has bogged to a snail's pace.  My local Macomb County defense suppliers are bogged-down with Muslim War contracts.  It has became tough for a Perky-speeder to get work done with magnesium, titanium, carbon fibre, secret micro-fibers and essential precision-machined sub-assemblies.  Nevertheless, I will still endeavor to get something together in time for The Brodak.

B-J Machining, the source of my spinner adapter, was pre-occupied with a special run of A-10 armour-piercering ammunition.
Bob Hornberger of Metrics Unlimited was pre-occupied with election of has daughter, Pamela, to our State Legislator.

Modeling is above politics, but not much above.


Title: Re: My second Perky
Post by: C.T. Schaefer on April 02, 2017, 05:43:26 AM
Looks like she's almost ready to go!
Title: Re: My second Perky
Post by: Ken Burdick on April 02, 2017, 07:57:57 AM
and I thought I had trouble getting a 4mm pressure tap for my D engine...........
Looks good Paul.


K
Title: Re: My second Perky
Post by: Paul Smith on April 12, 2017, 02:23:41 PM
Springtime in Michigan means moving the paint shop to the barn.
Not everybody loves the smell of butyrate in the morning.
Title: Re: My second Perky
Post by: Lyle Spiegel on May 07, 2017, 06:50:16 AM
How does BH Phantom compare to Perky? From pics it looks about same.
Title: Re: My second Perky
Post by: Paul Smith on May 07, 2017, 08:17:40 AM
Pretty close, but it's not exactly a Perky.  It would probably be a fair contest, but deal is a deal.

I noticed that an RC on line shop was offering Phantoms at a discount price & I tried to order a couple on Day One.  Sold out already !!