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RE: Yet another Sig Something Extra Build - 6/6/2008 4:00:38 AM   
iron eagel



Posts: 1203
Joined: 7/15/2004
From: Middleboro, MA, USA
Status: offline 		Thanks Bob!
Can not wait to see what you came up with!
Like I told you, trying to do it with the software I have was a real struggle.
I went to bolt the landing gear on tonight and found out I need longer screws than I have, that figures... At least I have the t nuts in place and all of the holes drilled out I had only drilled the pilot holes and had fastened the landing gear with small screws so I could measure up and build the cooling duct. At least I did get that far, better getting a little done at least rather than nothing. As far as the build the wing roots are the last major portion of the fuselage that needs to be done before starting the finish on it. I still need to shape the ailerons and might get started on that tonight, at least I can get the carbon fiber trailing edge installed and start shaping them. Then I can cut them for the flaps I have already got the hinges set up and all I need to do is to shape the ailerons put the sheathing on and then do the finish. I really want to be working on applying the carbon fiber veil in the near future, I am going to try to get to a hardware store and pick some bolts in the morning after the doctors before I go to work. I really wanted to get the duct mounted up tonight but that did not come to pass, Oh well par for the course of late it seems. But all in all most of the heavy building is done, other than the fairings for the wing roots all of the heavy duty shaping is done, so now it is mostly the finish and installing linkage and the engine left to do. Hopefully the finish will go fairly quickly but who knows a lot will depend on how much time I get to work on it given all of the doctors appointments I have this month. Then we can always figure on the wife throwing stuff my way that she "needs" done, plus I have yet to get to the field to actually fly yet this year.

_____________________________

The Wrights never crashed, they only had hard landings. I 've had some hard landings myself. AMA EAA AOPA revver #185

(in reply to N1EDM)
       Post #: 201

RE: Yet another Sig Something Extra Build - 6/7/2008 12:58:06 AM   
N1EDM



Posts: 1841
Joined: 7/19/2002
From: Brockton, MA, USA
Status: offline 		Hi Paul,

I've already PM'd you about the drawings... Hope you got the bolts you needed. If not, let me know what you need - I might be able to help with what I have in my own collection..

Believe it or not, I actually have some steel bolts in my larder... Not everything that I have is held together with nylon bolts

Bob

_____________________________

An expert is someone who has been doing it for 15 minutes longer than you.

(in reply to iron eagel)
       Post #: 202

RE: Yet another Sig Something Extra Build - 6/7/2008 4:57:03 PM   
iron eagel



Posts: 1203
Joined: 7/15/2004
From: Middleboro, MA, USA
Status: offline 		Bob,
I'll stop by the field on my way to work today, to pick them up.
Thanks so much for your help, I owe you big time!
The wing roots should really clean up the aerodynamics of the fuselage quite a bit, by reducing the disturbed airflow cause by the square root to fuselage joint, and eliminating some more of the flat fuselage sides. The overall effect should really blend the wing to the fuselage a lot better, especially on the top side. Now just what overall effect this will have on the performance may be minimal but it ought to look cool if nothing else. Another plus is that the root modification along with the carbon fiber veil should add a lot of strength to the fuselage sides at least as stiffness goes, now to see if I can keep the weight down.

Regards
Paul

_____________________________

The Wrights never crashed, they only had hard landings. I 've had some hard landings myself. AMA EAA AOPA revver #185

(in reply to N1EDM)
       Post #: 203

RE: Yet another Sig Something Extra Build - 6/7/2008 5:36:56 PM   
N1EDM



Posts: 1841
Joined: 7/19/2002
From: Brockton, MA, USA
Status: offline 		Not sure if I can get them to the field before you get there... I was going to drop them off tomorrow, but might be able to sneak out today instead.... I didn't want to see you make a trip for nothing....

Bob

_____________________________

An expert is someone who has been doing it for 15 minutes longer than you.

(in reply to iron eagel)
       Post #: 204

RE: Yet another Sig Something Extra Build - 6/8/2008 4:30:53 AM   
iron eagel



Posts: 1203
Joined: 7/15/2004
From: Middleboro, MA, USA
Status: offline 		Thanks to the efforts of N1EDM you can see how the wing fairings will look on my something extra.
Many thanks Bob!

If ever there was a case of “Now that’s I’m talking about” this is one.
These are the prints I will be making the patterns from. If you look you can see where the rib outline is drawn on the inside part which will be cut away to allow the wing to but into the fuselage. The height of the thickest part of the faring will be blended into the canopy hatch and forward hatch cover. The front of the fairing will be blended into the cowl fairings, the bottom and back will blend very nicely into the lower part of the fuselage. This will really eliminate both a lot of the flat side surface of the fuselage, and the square joint of the wing and fuselage. I am interested in how this will affect the over all performance. My theory is that this will reduce a lot of the turbulent airflow over the rear of the fuselage and tail feathers.



Attachments
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_____________________________

The Wrights never crashed, they only had hard landings. I 've had some hard landings myself. AMA EAA AOPA revver #185

(in reply to N1EDM)
       Post #: 205

RE: Yet another Sig Something Extra Build - 6/8/2008 5:34:26 AM   
N1EDM



Posts: 1841
Joined: 7/19/2002
From: Brockton, MA, USA
Status: offline 		Glad that they worked, Paul. Let's hope that I got that inner profile right.... It looks like you have already double-checked it.

Bob

_____________________________

An expert is someone who has been doing it for 15 minutes longer than you.

(in reply to iron eagel)
       Post #: 206

RE: Yet another Sig Something Extra Build - 6/8/2008 6:32:30 AM   
iron eagel



Posts: 1203
Joined: 7/15/2004
From: Middleboro, MA, USA
Status: offline 		Oh you got it right the inner profile is compounded because of how they join to the flaps (what would be the stock aileron roots). I wanted the root fairing a smother shape then the profile of the wing root to aileron is. In the stock SE the aileron is just a flat 1/4 inch slab that extends out 3 - 5/16ths from the back of the wing and it really does not fit the taper of the root wing rib. Look at the plans for the SE the inner to ribs should have been a higher % of the cord in thickness to allow for a better flow as the cord of the aileron gets bigger. Even tapering the aileron as I am is not going to change that, so this was the best idea I could come up with as a way to improve the airflow at the root, without a total redesign of the wing. Besides I am going to sand the inside of it to fit the finished wing root so close counts, without a laser cutter I am going to have to settle for that. A three axis CNC type of mill with a rounded router bit would be a nice way to shape them..

There is an idea for a tool she could get me for fathers day, LOL...

_____________________________

The Wrights never crashed, they only had hard landings. I 've had some hard landings myself. AMA EAA AOPA revver #185

(in reply to N1EDM)
       Post #: 207

RE: Yet another Sig Something Extra Build - 6/8/2008 1:31:13 PM   
N1EDM



Posts: 1841
Joined: 7/19/2002
From: Brockton, MA, USA
Status: offline 		Yeah, I could make a lot of good use for a Laser Cutter too... I wonder if I have a spare $10K hanging around here somewhere?????

Bob

_____________________________

An expert is someone who has been doing it for 15 minutes longer than you.

(in reply to iron eagel)
       Post #: 208

RE: Yet another Sig Something Extra Build - 6/9/2008 4:29:44 AM   
iron eagel



Posts: 1203
Joined: 7/15/2004
From: Middleboro, MA, USA
Status: offline 		I have read a few articles on both CNC Milling and laser cutters; I believe that you can put on together for far less than that. Roughly 25% of what they typically cost to buy and I have thought about it, because I used to work with that type of equipment that worked down to 5 micron accuracy. Some day I’ll think about it more seriously…

Anyhow back to reality…

I picked up what I needed for the patterns for the wing root fairings today, and am currently working on making them up, as well as working on the cowl. I have the templates on the stock for the templates for the wing root but wait until tomorrow to cut them. So in the meantime I have drawn the parting line on the cowl and am going to cut the cowl so the lower half of it can be removed for access to the engine and its connections. In order to be able to get the cowl over the engine and muffler it has to be in two pieces but I wanted to build it in one piece so it would fit together better. Some lite ply for guides and that it finished. Not to mention it will be a lot easier to install the rest of the baffles with it in two pieces so I don’t feel like I am working on a “ship in a bottle”. The way it is set up I won’t have to pull the spinner and prop if I need to get to the adjustments or linkage, just four screws and the bottom of the cowl comes off and I can get at every thing. With the exhaust sticking straight out of the bottom of the cowl there was not enough wiggle room to get it over the prop shaft and the exhaust at the same time unless I had a lot more room anyhow and that would have meant a much larger cowl and that would have really been a pain!

I’ll post some more pictures tomorrow night.


< Message edited by iron eagel -- 6/9/2008 4:40:45 AM >

_____________________________

The Wrights never crashed, they only had hard landings. I 've had some hard landings myself. AMA EAA AOPA revver #185

(in reply to N1EDM)
       Post #: 209

RE: Yet another Sig Something Extra Build - 6/10/2008 3:47:11 AM   
skyraider71


 

Posts: 243
Joined: 5/6/2008
From: mount washington, KY, USA
Status: offline 		I think the only mod the Somthin' Extra needs is
taller landing gear, and an extended rudder. I
love mine, if I built another one, I would make
these minor changes.

_____________________________

Busting props, and shredding Mono-cote since 1999

(in reply to iron eagel)
       Post #: 210

RE: Yet another Sig Something Extra Build - 6/11/2008 4:22:42 AM   
iron eagel



Posts: 1203
Joined: 7/15/2004
From: Middleboro, MA, USA
Status: offline 		As you pointed out the Sig Somethin Extra actually flies fine with no or very little modifications and is a nice airplane as it is. I just decide to kick it up a few notches, and if you take the time to do some more modifications you can really kick it up a several notches. This build was intended to hone my building skills, after years of absence from the hobby, and gain some knowledge of new materials, before I move on to some more esoteric aircraft. More than anything it is just a fun experiment at trying some new things and ideas. Where I can not ever build an airplane totally stock, I just took it to an even higher level with this one. I enjoy building as much if not more than flying sometimes and during the winter months and bad weather, it is a good way to keep playing with airplanes. Since I had this kit to build and had a reason for flying an airplane that was aerobatic as well it fell victim to my ideas for improvement. Had I not had a major problem with my health, I would have had it done a month ago, but I have been able to work on it more of late.

In this build I went with the taller landing gear and an upgrade to the tail wheel to allow for the use of a bigger diameter prop on the OS 55 AX that I selected for power. Many others have enlarged the rudder and elevator to enhance the performance so I did so as well. What I threw in was a few more enhancements to the overall design. One was to beef up the tail structure to eliminate the tail braces. To me they detract from the overall look of the plane as adding a lot of drag. I had also wanted to experiment with a pressure cowl as well, and the entire arrangement was built to add an enhancement to knife edge performance as well as, eliminating drag from the stock nose. The enhanced knife edge performance should result from side area that is added ahead of the COG by the cowl and cooling duct. Where I intend to build a couple of airplanes that where going to utilize the pressure cowl concept in the future I wanted to experiment with it now since I was building a kit I and saw some possible room for improvement at the same time. Along with all of that I decided to enhancement of the wing attachment to the fuselage was not all that bad of an idea either. Now you have some more insight as to what I am doing with this build...

I did not have a chance to work on it yesterday or today because of the heat but they tell us that it should cool down a bit tomorrow. Overnight it seemed the temperature shot up by some 50 degrees and it was hard for me to get acclimated to that type if a change in three days, it was dam near 100 today and Friday it was around 50.


_____________________________

The Wrights never crashed, they only had hard landings. I 've had some hard landings myself. AMA EAA AOPA revver #185

(in reply to skyraider71)
       Post #: 211

RE: Yet another Sig Something Extra Build - 6/12/2008 6:17:45 AM   
iron eagel



Posts: 1203
Joined: 7/15/2004
From: Middleboro, MA, USA
Status: offline 		The cowl has had the parting line cut into it and the plywood alignment and mounting tabs installed. I have also cut, soaked and shaped the intake baffle. Tomorrow night after it has dried I will install it into the cowl and fabrication of the cowl will be finished. I will then remount the motor and check for fit, hopefully there will be no issues so I can install the muffler and cut the holes for the exhaust pipes, and the high speed needle extension. After this done the lower part of the cowl can be removed for access to the fuel lines, linkage and low speed adjustment by removing four screws.

Attachments
Click to see fullsize image.
Click for fullsize 		Click to see fullsize image.
Click for fullsize


_____________________________

The Wrights never crashed, they only had hard landings. I 've had some hard landings myself. AMA EAA AOPA revver #185

(in reply to iron eagel)
       Post #: 212

RE: Yet another Sig Something Extra Build - 6/14/2008 2:32:58 AM   
N1EDM



Posts: 1841
Joined: 7/19/2002
From: Brockton, MA, USA
Status: offline 		I like the cowl. Remember when that was the way that they used to be built as a matter of course?

Nice work on that. Can't wait to see it up close and personal at the Field.

Bob

_____________________________

An expert is someone who has been doing it for 15 minutes longer than you.

(in reply to iron eagel)
       Post #: 213

RE: Yet another Sig Something Extra Build - 6/14/2008 8:14:20 PM