Building Thread for RSM New Electric P40 Profile (Finished Wing 12/16/2013)

[Mike Griffin]

I was asked to do a test build for the prototype on Eric's new Electric P40 Profile.  One of the unique features of this model is that it utilizes a continuous RIBBON hinge for the elevators and flaps thereby sealing the hinge lines in on step.  This is done by using two piece flaps, stabs and elevators.  Here are some pictures of the build of the fuselage and stab.  There will be more to come as the build progresses...

Mike

[Mike Griffin]

More pictures of Electric P40

[Mike Griffin]

There is clear plastic in the kit already cut to fit the cockpit framework for both sides,

[Mike Griffin]

Some more

[Mike Griffin]

Another

[dennis lipsett]

Another

I seem to remember that technique being used on a model about 50 years ago. I know that I had it but my memory banks have failed me on it's name.

[Mike Griffin]

It is really a simple way to get a sealed hinge line.

Mike

[Mike Griffin]

Here are a few shots of the plastic cut outs that come with the kit and how they apply to the laser cut cockpit framework.  I used canopy glue to attach them.  Also I took an old blue file folder and cut a template from them tho protect them during spray painting of the fuselage.

Mike

[Will Davis]

AJ firecat used the cloth in between wood for the hinges,  great idea

[Rick_Huff]

Mike,
What is the sheeting material (and thickness) for the fuselage?
Rick

[Mike Griffin]

Rick the core is 3/8" and you have two 1/16" sheeted sides for a total of 1/2" thick fuselage...

Mike

[Dennis Toth]

Mike,
Looks interesting, where and how is the battery secured? Seems that with all the lighten holes the ship will be pretty light in the back and with the battery in the nose might need significant tail weight?

On a couple ships I've done I do a rough moment/weight balance to see how far back the battery needs to be to get correct CG location (mine have had 1/3 ish of the battery in back of the wing LE). Where is the ship suppose to balance at?

Best,       DennisT

[Crist Rigotti]

Mike,
Looks interesting, where and how is the battery secured? Seems that with all the lighten holes the ship will be pretty light in the back and with the battery in the nose might need significant tail weight?

On a couple ships I've done I do a rough moment/weight balance to see how far back the battery needs to be to get correct CG location (mine have had 1/3 ish of the battery in back of the wing LE). Where is the ship suppose to balance at?

Best,       DennisT

"Nose heavy" electrics are good!

[Mike Griffin]

Here are a couple of more pictures.  These are of the rudder and the final lamination to create the stab/elevator unit.

Mike

[ericrule]

Mike is incorrect about the fuselage construction. Center core is 1/4" with two 1/8" balsa sides for a total of 1/2". For those who really want a stiff fuselage I would add some light weight glass cloth or carbon fiber between the core and sides.

Eric Rule

[Mike Griffin]

Eric is exactly right about the core and sheeting.  I knew that.  LOL... guess I just had a brain fart for a second on that...

Sorry Rick...

Mike

[Fred Cronenwett]

I have a profile b29 that is six feet long with 1/16 balsa sides and 3/4 x 1/2 sticks for the internal structure. Then I put carbon fiber cloth on the inside of the fuselage skins. Then the outside of the entire fuselage was fiberglassed with 3/4 ounce glass. That fuselage is very stiff!

Nacelles were built the same way without any plywood doublers.

Fred

[john e. holliday]

Well, I am going to jump in here.   When I laminated the 1/4 inch sheet fuselage of Mike Pratt's Primary Force I thought that it would be limber.   After the Gorilla Glue set up and I pulled all the clamps off it was the stiffest piece of balsa I had ever seen for 1/2 inch thick balsa.   This is before I put the silkspan on the fuse for finishing.

[Serge_Krauss]

Yes, when you laminate pieces with unlike grain, you gain a lot of stiffness. I like the idea of the CF inside the 1/16" sides as well as the FG outside, although I haven't yet used both. My last profile had 1/2" core with 1/16" laminations and biased FG w/resin for a skin. It is very stiff and torque resistant, but the inner CF seems like positive step. I'll probably try that. Eric's kit looks gorgeous.

SK

[Mike Griffin]

Here are some more pictures of constructing the flaps with full span ribbon hinges on flaps.

[Mike Griffin]

Two More

[Avaiojet]

Mike,

I like it! Good work.

No reason this couldn't work with built up surfaces also?

Mike, do you still have a website?

Charles

[Mike Griffin]

Hi Charles...yes you can make this work with built up surfaces also.  The website I now have is www.controllineflyers.com.   Thanks Charles.

Mike

[Avaiojet]

Hi Charles...yes you can make this work with built up surfaces also.  The website I now have is www.controllineflyers.com.   Thanks Charles.

Mike

WOW! Great website! Kudos!

Mike,

First time I've seen that website. Well organized, nice presentation and great photos! Something there for everyone!

It's got me thinking.

Charles

[Mike Griffin]

These pictures show the plywood end cap, and how you glue it to the root end of the flap to use as a template to shape the flaps.  Note the Ribbon hinge is already between the laminations of the flaps.

[MarcusCordeiro]

Any more??

Marcus

[Mike Griffin]

Hi Marcus

There will be more.  This build is taking me a little longer than normal because of some family activities we have been having..new grandchild...etc...LOL... I will be starting the wing real soon.  There will be more to come I promise...

Mike

[Mike Griffin]

Charles thank you for the compliment on the web site.  I have not been able to go in lately and add some things just for lack of time.  I need to do some work on it...

Mike

[Mike Griffin]

I started building the wing today.  Here are some pictures of construction.  Had to come back and do an edit.  The span is 52" and the area is 624".

Mike

[Mike Griffin]

A couple of more for wing construction

[Avaiojet]

Mike,

What's the span?

Did I miss that?

Charles

[Mike Griffin]

I forgot to post the span Charles.  It is 52" and the area is 624".  Sorry I forgot that.

Mike

[MarcusCordeiro]

Love the jig...
Very neat bench... Does it ever get dirty???

Marcus

[john e. holliday]

Is that the same standards that CLC sells?   

[Mike Griffin]

Hey Doc.. yes I bought those from CLC a few years ago. It is a great jig.  Takes a little time to set up but builds a straight wing.  Hi Marcus.. You like that neat bench huh?  I will let you in on a little secret...I clean it up to take pictures... actually I keep all the supplies on another bench you cannot see but the buiilding bench I do try to keep clear of clutter.  I have screwed up some wings by having objects on the bench get tangled up with ribs.   I am not a neat freak I assure you..

Mike

[john e. holliday]

Yes it does take time to set up, but once set up it is great.   I have built several planes on mine.   Hope Jim gets his life back together.

[Mike Griffin]

Me too Doc

[Mike Griffin]

Progress on the wing. Glueing top spar in

[john e. holliday]

The small pics had me going as far as the spar.   Once enlarged I could see.   I have a box of the weights that I got from Jim at VSC one year.   Put a light coat of silicon glue on one side as they kept sliding off the surfaces I was putting them on for weight.  Yes I let the glue dry first before using. 

[Mike Griffin]

These 4 pictures show how I attach the leadouts to the carbon fiber bell crank.  I use .027 lead out wire and 1/16th diameter copper tubing for the bushings.  The lead outs are wrapped with .28 guage copper wire, and I apply a dab of CA to the wrapping and then use the heat shrink tubing to secure the leadouts to the bellcrank.  The post is 1/8" music wire and I have placed two wheel collars,one above and one below the bell crank to hold it in the proper posititon.

Mike

[Mike Griffin]

These two pictures show the bottom of the wing and the landing gear blocks and bottom bell crank plate installed.

[Mike Griffin]

The trailing edge sheeting is precut and this shows the installation of the bellcrank and trailing edge sheeting.

[Mike Griffin]

More

[Mike Griffin]

More

[Mike Griffin]

I just wanted to make a note here on the building of this kit up to this point.  With the exception of just a couple of small details that had to be corrected, this test build on this kit has gone smoother than any I have ever done. Eric Rule at RSM has really thought this profile out carefully and although the continuos ribbon hinge technique is not new, this is the first time I can remember seeing it incorporated into a kit.  There is not concrete requirement that you have to use the ribbon hinge but it makes sense to me.

I have no weighed any of the components yet but I can tell you it is LIGHT... 

I will be be posting more pictures of the wing construction then I will be assembling the plane and finishing it.  I hope this thread has been interesting and informative so far.

Mike

[john e. holliday]

Hey Mike it looks like there is no washer on top of the ball link at the bell crank.  I have in the past had one slip off the ball for some reason.  Since then I have put a washer between the bolt head and the ball link.   Just a thought.

[Mike Lauerman]

Good catch, Doc. I lost my Southwick Skylark to that very same thing. Still use 'em, WITH washer now

[Mike Griffin]

Hi Doc

This is a test build to make sure everything fits before Eric releases the kit.  The washer on top of the ball link is something that the individual builder will have to determine if he wants to put on.  People have various ideas of how they want to construct their control linkages and that is why I never did include hardware in the kits I produced.   I left up to the builder to decide.  Thank you for your suggestion.

Mike

[ron young]

  Hi Mike
Im enjoying the thread very much can you tell me if this wing jig is still available from anyone ?
Thanks
Ron

[Mike Griffin]

Hi Ron

Jim Snelson was the person who offered this jig back a few years ago when he had CLC (Control Line Central)  From what I have read on this forum Ron, I think that Jim may have closed down CLC but I am not absolutely sure about that.  If someone on here still has Jim's phone number or e mail address, you can contact him and see if he has any of these jigs left to sell.  At one time I had a contact number but have lost it since.  The last e mail address I had for Jim was, clcentral@msn.com.  I am not sure if that is still valid but you can certainly try it.

Hope this helps.

Mike