 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
frank.goodnight(at)att.ne
Guest
|
 Posted: Tue Nov 16, 2010 4:44 pm Post subject: Cracked spar on fire star. |
 |
|
----- Forwarded Message ----
From: Jon Lockhart <jonlock2(at)gmail.com>
To: frank.goodnight <frank.goodnight(at)att.net>; customersupport(at)tnkolbaircraft.com; kolb-list(at)matronics.com
Sent: Tue, November 16, 2010 6:02:16 PM
Subject: Cracked spar on fire star.
Please review the photos. Thanks, Frank Goodnight
| | - The Matronics Kolb-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kolb-List |
|
| Description: |
|
| Filesize: |
1.35 MB |
| Viewed: |
1231 Time(s) |
|
| Description: |
|
| Filesize: |
1.34 MB |
| Viewed: |
1231 Time(s) |
|
|
|
| Back to top |
|
 |
flykolb(at)pa.net
Guest
|
| Posted: Tue Nov 16, 2010 6:02 pm Post subject: Cracked spar on fire star. |
|
|
Frank,
There are 2 issues:
Roughly speaking, an HKS has approximately twice the power impulse than a two-stoke because it has only half of the power pulses.
(A 2-stroke piston fires every time in goes down, but only every other time on a 4-stroke.) So the HKS will place a higher stress on the structure than a 2-stroke of comparable power.
Somewhere along the way, the brace gusset from the motor mount got moved to the center of the square tube. Formerly it was welded to the leading edge of the square tube.
On your frame the power pulses are transmitted to the center of the thin wall of the square tube – this will result in a certain amount of flexing which could possible lead to the cracking you have.
A possible fix would be the addition of a gusset to get the forces directly to the corner of the square tube.
If someone is going to sound an alarm about the cracking, I think a distinction could be made between the frames that have the center orientated location vs the edge oriented location.
Dennis
From: owner-kolb-list-server(at)matronics.com [mailto:owner-kolb-list-server(at)matronics.com] On Behalf Of frank goodnight
Sent: Tuesday, November 16, 2010 7:28 PM
To: kolb-list(at)matronics.com
Subject: Fw: Cracked spar on fire star.
----- Forwarded Message ----
From: Jon Lockhart <jonlock2(at)gmail.com>
To: frank.goodnight <frank.goodnight(at)att.net>; customersupport(at)tnkolbaircraft.com; kolb-list(at)matronics.com
Sent: Tue, November 16, 2010 6:02:16 PM
Subject: Cracked spar on fire star.
Please review the photos. Thanks, Frank Goodnight
[quote][b]
| | - The Matronics Kolb-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kolb-List |
|
|
|
| Back to top |
|
|
jbhart(at)onlyinternet.ne
Guest
|
| Posted: Wed Nov 17, 2010 8:35 am Post subject: Cracked spar on fire star. |
|
|
| Quote: | From:<Frank Goodnight>
Sent: Tue, November 16, 2010 6:02:16 PM
Attachment Converted:
"c:\eudora\attach\aircraft photo 1.JPG"
Attachment Converted:
"c:\eudora\attach\aircraft photo 1
(2).JPG"
|
Frank,
Thank you for your photos. I just came back from checking the FireFly. My
braces weld to the corner of the square tube. I did not find any cracks,
but due to using powder coat, they would have to be quite large to see them.
I flew the FireFly with the Victor 1+, a 313cc one cylinder engine, for 188
hours. One of the advantages of replacing it with the MZ34 was to reduce
displacement and firing impulse vibration. This has been proven out in that
the FireFly is much smoother and quieter in flight. If you are using a
heavy, high inertia propeller, you may want to consider changing to a
smaller, lighter, low inertia propeller. This will allow more firing
impulse energy to be dissipated into the propeller than being transferred to
the mounts and on to the cage.
Jack B. Hart FF004
Winchester, IN
| | - The Matronics Kolb-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kolb-List |
|
|
|
| Back to top |
|
|
captainron1(at)cox.net
Guest
|
| Posted: Fri Nov 26, 2010 8:35 pm Post subject: Cracked spar on fire star. |
|
|
Is that a corrosion crack?
It being a long the seem does not look like fatigue crack.
---- frank goodnight <frank.goodnight(at)att.net> wrote:
=============
----- Forwarded Message ----
From: Jon Lockhart <jonlock2(at)gmail.com>
To: frank.goodnight <frank.goodnight(at)att.net>; customersupport(at)tnkolbaircraft.com; kolb-list(at)matronics.com
Sent: Tue, November 16, 2010 6:02:16 PM
Subject: Cracked spar on fire star.
Please review the photos. Thanks, Frank Goodnight
--
kugelair.com
[quote][b]
| | - The Matronics Kolb-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kolb-List |
|
|
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
