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williamtsullivan(at)att.n
Guest

Posted: Thu Jan 15, 2009 9:38 am Post subject: Landing gear

Jim Hauck- Last May you suggested using steel tubing for the landing legs on a Firefly or old Firestar with the 1" legs.  Your suggestion was to go half way down with the 1", and change to 3/4".  I am considering steel legs, and wondered about the half way comment.  Halfway from the bottom of the "A" frame?  I know about using 4130 and hardening to R48.  Do you pre-drill before hardening?  I haven't ordered any legs yet, but If I go to the new 1 1/8" Firefly legs I will have to drill out the aluminum tube spacer in there.

   Also, when joining the 1" to the 3/4" do you just run the bolt through the "A" frame at the usual spot, or another bolt lower, or a weld at the top and allow the lower joint to move?

  

                                                      Bill Sullivan

                                                      Windsor Locks, Ct.

                                                      5 degrees and overcast, light snow flurries

 [quote][b]

mdnanwelch7(at)hotmail.co
Guest

Posted: Thu Jan 15, 2009 10:41 am Post subject: Landing gear

Bill C

  

   I'm not Jim C but I can answer your question regarding drilling into the 4130 hardened to R-48.

 I just drilled into my gear legs a few weeks ago C to secure my axles.  I failed to drill them before I

 sent them off to be Rockwell hardened.  Big mistake!!  Those suckers are hard as a bleaping rock!!

  

   They were so hard C I couldn't get a punch to make a centering hole dent.  Suffice to say C if you want

 to do any machining on them C do it PRIOR to hardening.  Drilling them afterwards is 20 times as difficult!

  

 Mike Welch

 MkIII

 +1 degree this morning C too cold to work on my plane in the shop.

   



   

 Date: Thu C 15 Jan 2009 09:37:37 -0800

From: williamtsullivan(at)att.net

Subject: Landing gear

To: kolb-list(at)matronics.com

       Jim Hauck- Last May you suggested using steel tubing for the landing legs on a Firefly or old Firestar with the 1" legs.  Your suggestion was to go half way down with the 1" C and change to 3/4".  I am considering steel legs C and wondered about the half way comment.  Halfway from the bottom of the "A" frame?  I know about using 4130 and hardening to R48.  Do you pre-drill before hardening?  I haven't ordered any legs yet C but If I go to the new 1 1/8" Firefly legs I will have to drill out the aluminum tube spacer in there.

   Also C when joining the 1" to the 3/4" do you just run the bolt through the "A" frame at the usual spot C or another bolt lower C or a weld at the top and allow the lower joint to move?

  

                                                      Bill Sullivan

                                                      Windsor Locks C Ct.

                                                      5 degrees and overcast C light snow flurries

 	  Quote: 	
		  



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Windows Live™ Hotmail®: Chat. Store. Share. Do more with mail.  Check it out.  [quote][b]

jimh474(at)embarqmail.com
Guest

Posted: Thu Jan 15, 2009 11:19 am Post subject: Landing gear

Bill;

  

 Do all drilling and welding prior to having them heat  treated.

  

 You want the gear legs to run all the way up in the  gear socket till they bottom out at the "V" junction of the gear  sockets.

  

 On my brothers Fire Star which we made steel gear legs  for way back in the late 80's we used 36 " gear legs. This give you more   ability to rotate on take off.

  

 On the Fire Star, I would use one size tubing for the  entire length as it is much heavier than the Fire Fly.

  

 Use 1 1/8" .120 wall tubing for your gear legs and for  the axle sockets use 7/8 .120 wall tubing. This will fit the 5/8  axle.

  

 I would weld tubing for the axle insert at + 7 degrees  camber. This will put your wheels about 2 degrees positive when you are in the  airplane.

  

 When you heat treat the chromemoly tubing it then  becomes a spring.

  

  

 If I can help you with anything else feel free to  ask.

  

 Jim Hauck

   [quote][b]

aslsa.rng(at)gmail.com
Guest

Posted: Thu Jan 15, 2009 11:42 am Post subject: Landing gear

Jim, If you don't mind a welding question, did you use any special gas when mig welding the Kolb frames or did you just use steel mix.



Thanks,

Rick



On Thu, Jan 15, 2009 at 1:17 PM, Jim Hauck <jimh474(at)embarqmail.com (jimh474(at)embarqmail.com)> wrote:

  	  Quote: 	
		         Bill;

  

 Do all drilling and welding prior to having them heat  treated.

  

 You want the gear legs to run all the way up in the  gear socket till they bottom out at the "V" junction of the gear  sockets.

  

 On my brothers Fire Star which we made steel gear legs  for way back in the late 80's we used 36 " gear legs. This give you more   ability to rotate on take off.

  

 On the Fire Star, I would use one size tubing for the  entire length as it is much heavier than the Fire Fly.

  

 Use 1 1/8" .120 wall tubing for your gear legs and for  the axle sockets use 7/8 .120 wall tubing. This will fit the 5/8  axle.

  

 I would weld tubing for the axle insert at + 7 degrees  camber. This will put your wheels about 2 degrees positive when you are in the  airplane.

  

 When you heat treat the chromemoly tubing it then  becomes a spring.

  

  

 If I can help you with anything else feel free to  ask.

  

 Jim Hauck

    [/b] 	




[b]

jimh474(at)embarqmail.com
Guest

Posted: Thu Jan 15, 2009 12:12 pm Post subject: Landing gear

Rick;

  

 Most of the welding I do on Kolb's, it TIG, when I use  MIG I use 25% Argon and 75% CO2. This keeps the splatter down  considerably.

  

 Jim H

   [quote][b]

williamtsullivan(at)att.n
Guest

Posted: Thu Jan 15, 2009 3:18 pm Post subject: Landing gear

  Thanks for the prompt responses.  Jim- I may downsize a bit from your recommendations, as this particular plane is probably lighter than the current Firefly.  John thinks it is a very early one, built to Part 103 specs.  I'll check weights,as I want to add brakes this time.

  If you have to drill a spring, spot anneal first.  Drill with lots of coolant, as heat will harden the material as you drill.  I have ended up with some weird looking drill bits finding this out.  Sometimes you don't know what the steel is, and it can be interesting trying to drill it.

 

                                             Bill Sullivan

                                             Windsor Locks, Ct

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Thu Jan 15, 2009 3:53 pm Post subject: Landing gear

Bill:

  

 The specs Jim gave you are the specs that  work.

  

 We didn't come up with them the first time  around.  We tried 1"X.090" heat treated to 42 RC.  These were our  first steel legs.  I didn't know where to start with heat treating.   Got the 42 RC from Max Air and went with it.  It was too soft.  48 RC  is hard enough, but not too hard.  They will bend 90 deg before they  break.  I have tested them in actual situations.

  

 If you go lighter, the system will fail  eventually.

  

 john h

 mkIII

  

 [quote]    

                               Thanks for the prompt responses.  Jim- I may downsize a          bit from your recommendations, as this particular plane is probably          lighter than the current Firefly.   

                                                               Bill Sullivan

                                                               Windsor Locks, Ct.

 	  Quote: 	
		   	
[b]

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

williamtsullivan(at)att.n
Guest

Posted: Thu Jan 15, 2009 4:26 pm Post subject: Landing gear

John- Do you think that spec might be a little too ridgid for a 103 plane?  Gross weight will be about 475 total.  Jim's original letter of May 19, 2008 gave me the lighter spec legs.

  

                                               Bill Sullivan

                                               Windsor Locks, Ct.

 8 degrees, and going to -1 tonight

 [quote][b]

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Thu Jan 15, 2009 4:42 pm Post subject: Landing gear

Bill:

  

 Those are the legs I flew very successfully with on  my 1986 original Firestar.

  

 Once heat treated, the legs are  springs.

  

 john h

 mkIII

 [quote]    

                               John- Do you think that spec might be a little too ridgid          for a 103 plane?  Gross weight will be about 475 total.  Jim's          original letter of May 19, 2008 gave me the lighter spec legs.

          

                                                                Bill Sullivan

                                                       Windsor          Locks, Ct.

          

 	  Quote: 	
		  

 	
[b]

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

williamtsullivan(at)att.n
Guest

Posted: Thu Jan 15, 2009 4:48 pm Post subject: Landing gear

I'll drill the sockets for the 1 1/8", if the weather ever gets warmer.  Thanks.

  

                                           Bill Sullivan

                                           Windsor Locks, Ct.

 [quote][b]

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Thu Jan 15, 2009 4:58 pm Post subject: Landing gear

Bill:

  

 My original FS came with 1" aluminum legs.  I  bent them taxiing before I even got in the air the first time.

  

 Tried Twinstar legs, 1.125", and bent them  too.  Then we started working on some heat treated steel legs.

  

 I had to remove the aluminum tube sleeve from the  gear leg sockets.  Made a simple home made slide hammer and went to  work.  Took a little effort but the sleeves lost the battle.  I also  had to clean up some places where the welds had burned through before I could  get the legs all the way into the socket up to the intersection where they  bottomed out.

  

 We used gear leg/axle sockets  initially.  After a couple failures, we started welding the axle  sockets to the bottom of the gear legs.  That fixed that  problem.

  

 john h

 mkIII

  

  

 [quote]                               I'll drill the sockets for the 1 1/8", if the weather ever          gets warmer.  Thanks.

          

                                                            Bill Sullivan

                                                            Windsor Locks, Ct.

 	  Quote: 	
		  

 	
[b]

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

williamtsullivan(at)att.n
Guest

Posted: Fri Jan 16, 2009 4:14 am Post subject: Landing gear

John and Jim- Thanks for the feedback.  It was just that old message (I had saved it) that caused the confusion.  I have 3 sets of the old 1" legs (all bent) that came with it- one set is 6061, bent while taxiing.  I have the old type axle fitting, 3/4" socket and a 5/8" tube for an axle.  I intend to re-fit with brakes, so changes have to be made.

   While I'm digging in your memories of that old Firestar- What kind of empennage attachment was on it?  Mine doesn't match any photos I have been able to find.  The lower "skeg" end has two pieces of steel tubing going forward into the fuselage, and no exterior supporting ring.  Old style?

  

 2 below zero at 7am, and where is the global warming they have been promising?

  

                                                    Bill Sullivan

                                                    Windsor Locks, Ct.

  

  



 [quote][b]

Dana

Joined: 13 Dec 2007
Posts: 1047
Location: Connecticut, USA

Posted: Fri Jan 16, 2009 4:29 am Post subject: Landing gear

At 07:13 AM 1/16/2009, william sullivan wrote:

 	  Quote: 	
		     While I'm digging in your memories of that old Firestar- What kind of 

 empennage attachment was on it?  Mine doesn't match any photos I have 

 been able to find.  The lower "skeg" end has two pieces of steel tubing 

 going forward into the fuselage, and no exterior supporting ring.  Old style?


	


I don't know about the FS, new or old, but that's how the US is built.



 	  Quote: 	
		    2 below zero at 7am, and where is the global warming they have been 

 promising?


	


Yeah, I have to leave the water dripping all night to keep the pipes from 

freezing.  But haven't you heard?  It's not "global warming" any more, it's 

"climate change".  That way they can say they're right no matter what the 

climate does.  The scientists are all abandoning the global warming thing 

like rats fleeing a sinking ship, leaving only the brain dead or corrupt 

politicians on board



-Dana

--

  Chaste: why virgins run.

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Fri Jan 16, 2009 7:04 am Post subject: Landing gear

Bill:

  

 I think you are referring to the tail post  attachment.

  

 That is the way it was done on early  Firestars.  No exterior ring.

  

 On my Ultrastar, the inboard rib attached to the  main spar with two tubes inserted into the spar.  This was a poor method of  attachment because it allowed the wing to twist.  Aileron input was  counteracted by wing twist.  One had to be very gentle with  ailerons.

  

 The Ultrastar was not the only aircraft with wing  twist problems.  One of my old Air Force buddies flew B-47's.  That  aircraft had the same problem as the Ultrastar.

  

 john h

 mkIII - 17F at hauck's holler

 [quote]    

    

    

   



                                           

           While I'm digging in your memories of that old Firestar-          What kind of empennage attachment was on it?  Mine doesn't match          any photos I have been able to find.  The lower "skeg" end has two          pieces of steel tubing going forward into the fuselage, and no exterior          supporting ring.  Old style?

          

         2 below zero at 7am, and where is the global warming they have been          promising?

          

                                                                     Bill Sullivan

                                                                     Windsor Locks, Ct.

          

          



 	  Quote: 	
		  

 	
[b]

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

Dana

Joined: 13 Dec 2007
Posts: 1047
Location: Connecticut, USA

Posted: Fri Jan 16, 2009 10:19 am Post subject: Landing gear

At 10:04 AM 1/16/2009, John Hauck wrote:

  	  Quote: 	
		   

 On my Ultrastar, the inboard rib attached to the main spar with two tubes inserted into the spar.  This was a poor method of attachment because it allowed the wing to twist.  Aileron input was counteracted by wing twist.  One had to be very gentle with ailerons. 	


 John, did you ever do the mod (I think it was Richard Swiderski who posted details on it) to add the collar on the wing root?  It's tempting, but a bit of work, and I wonder how much improvement it would actually make.



 -Dana

 

 --

  Be wary of strong drink. It can make you shoot at tax collectors-- and miss.    [quote][b]

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Fri Jan 16, 2009 10:35 am Post subject: Landing gear

Dana:

  

 No, we did not make that change.  Would have  been easier to build new wings with an updated inboard rib.

  

 Also, the improvements of the original FS over most  of the problems with the US out weighed any decision to put more time and money  in the US.

  

 The US had a lot of little problems and was easy to  bend things.

  

 The FS also had problems in some of the same  areas.  Winter of 1988 and 89, Jim and I completely overhauled and modified  my FS.  A lot of the initial problems were solved by Jim adding a couple  additional tubes here and there.

  

 john h

 mkIII

  

  

 [quote]    John, did you ever do the mod (I think it    was Richard Swiderski who posted details on it) to add the collar on the wing    root?  It's tempting, but a bit of work, and I wonder how much    improvement it would actually make.



-Dana

 

[b]

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

williamtsullivan(at)att.n
Guest

Posted: Fri Jan 16, 2009 10:37 am Post subject: Landing gear

Dana- Has yours been fixed?

  

                                  Bill Sullivan

                                  Windsor Locks, Ct.

 [quote][b]

herbgh(at)nctc.com
Guest

Posted: Fri Jan 16, 2009 10:55 am Post subject: Landing gear

John



   Coming from you...those "here and there tubes" sound important...can you embellish?   



   Also  Dana and John...I am planning to use a set of modified ultra star root ribs on my Firefly/Firestar /ultrastar Tri Fly  hybrid...  Is the US "h" section sort of root attachment to  spar considered to be inferior...Looks plenty strong to me. Herb  



 

 At 12:35 PM 1/16/2009, you wrote:

 [quote]Dana:

  

 No, we did not make that change.  Would have been easier to build new wings with an updated inboard rib.

  

 Also, the improvements of the original FS over most of the problems with the US out weighed any decision to put more time and money in the US.

  

 The US had a lot of little problems and was easy to bend things.

  

 The FS also had problems in some of the same areas.  Winter of 1988 and 89, Jim and I completely overhauled and modified my FS.  A lot of the initial problems were solved by Jim adding a couple additional tubes here and there.

  

 john h

 mkIII

  

  

    John, did you ever do the mod (I think it was Richard Swiderski who posted details on it) to add the collar on the wing root?  It's tempting, but a bit of work, and I wonder how much improvement it would actually make.



  -Dana

   

 

  

 [b]

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Fri Jan 16, 2009 11:07 am Post subject: Landing gear

Herb:

  

 The original method of attaching inboard rib to  main spar on the US was less than desireable.  It allowed the wing to twist  when ailerons were operated, effectively canceling out aileron input.  That  is why Homer came up with the collar for attaching main spar and also tail  post.  Light aileron loads worked pretty good, but if you had to get a  little heavy handed, the more aileron applied the more the wing would  twist.  Scared hell out of me first time I got into that situation.  I  was used to flying helicopters.  When I gave them cyclic input the  helicopter responded immediately.  Brand new to airplanes and especially  the Ultrastar, I dove on my house, pulled up and tried to do a big wing over,  but the more aileron I put in the more the wing twisted and I ended up  effectively wings level.  Had a lot to learn about these little  airplanes.

  

 john h

mkIII

  

  

 [quote]      Also  Dana and John...I am    planning to use a set of modified ultra star root ribs on my Firefly/Firestar    /ultrastar Tri Fly  hybrid... Is the US "h" section sort of root    attachment to spar considered to be inferior...Looks plenty strong to me.    Herb  

 

 

[b]

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

herbgh(at)nctc.com
Guest

Posted: Fri Jan 16, 2009 11:38 am Post subject: Landing gear

Brings up 'nuther question...Did you have the  braces on the drag spar?    Also wondering if my 24 foot wing span will be as susceptible to the twist?  Logically it would not.. 



  Thanks  Either way..I will make the collar...or hook a couple out of Travis!    Herb  



 

 At 01:06 PM 1/16/2009, you wrote:

 [quote]Herb:

  

 The original method of attaching inboard rib to main spar on the US was less than desireable.  It allowed the wing to twist when ailerons were operated, effectively canceling out aileron input.  That is why Homer came up with the collar for attaching main spar and also tail post.  Light aileron loads worked pretty good, but if you had to get a little heavy handed, the more aileron applied the more the wing would twist.  Scared hell out of me first time I got into that situation.  I was used to flying helicopters.  When I gave them cyclic input the helicopter responded immediately.  Brand new to airplanes and especially the Ultrastar, I dove on my house, pulled up and tried to do a big wing over, but the more aileron I put in the more the wing twisted and I ended up effectively wings level.  Had a lot to learn about these little airplanes.

  

 john h

 mkIII

  

  

      Also  Dana and John...I am planning to use a set of modified ultra star root ribs on my Firefly/Firestar /ultrastar Tri Fly  hybrid... Is the US "h" section sort of root attachment to spar considered to be inferior...Looks plenty strong to me. Herb  

   

   

 [/b]

  

 [b]

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