---------------------------------------------------------- Kolb-List Digest Archive --- Total Messages Posted Sun 04/16/17: 25 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:55 AM - Mk3 C Clevis Pins (Norman) 2. 04:58 AM - Mk3 C Clevis Pins (Norman) 3. 06:53 AM - New Break-away Tail Wheel (KJ4CTZ) 4. 07:20 AM - Re: New Break-away Tail Wheel (william sullivan) 5. 07:24 AM - Re: Mk3 C Clevis Pins (B Young) 6. 07:35 AM - Re: Mk3 C Clevis Pins (william sullivan) 7. 08:11 AM - Re: New Break-away Tail Wheel (George Helton) 8. 08:58 AM - Re: New Break-away Tail Wheel (KJ4CTZ) 9. 09:13 AM - Re: Re: New Break-away Tail Wheel (william sullivan) 10. 03:01 PM - Fw: another video and flight (Larry Cottrell) 11. 03:37 PM - Re: Leading edge bracing; was: Kolb Twinstar (original version) info request (John Hauck) 12. 03:52 PM - Re: Re: Leading edge bracing; was: Kolb Twinstar (original version) (John Hauck) 13. 04:10 PM - Re: Fw: another video and flight (B Young) 14. 04:27 PM - Re: Baby's got some new shoes (John Hauck) 15. 04:47 PM - Re: Leading edge bracing; was: Kolb Twinstar (original version) info request (John Hauck) 16. 04:53 PM - Re: Baby's got some new shoes (Larry Cottrell) 17. 05:00 PM - Re: Baby's got some new shoes (Russ Kinne) 18. 05:15 PM - Re: Baby's got some new shoes (Larry Cottrell) 19. 05:25 PM - Re: Baby's got some new shoes (Russ Kinne) 20. 05:50 PM - Re: Baby's got some new shoes (John Hauck) 21. 06:03 PM - Re: Leading edge bracing; was: Kolb Twinstar (original version) info request (Charlie England) 22. 06:09 PM - Re: Re: Leading edge bracing; was: Kolb Twinstar (original version) (Charlie England) 23. 06:10 PM - Re: Baby's got some new shoes (John Hauck) 24. 06:19 PM - Re: Baby's got some new shoes (Larry Cottrell) 25. 06:30 PM - Re: Re: New Break-away Tail Wheel (George Helton) ________________________________ Message 1 _____________________________________ Time: 04:55:35 AM PST US From: Norman Subject: Kolb-List: Mk3 C Clevis Pins Hi again, could someone tell me the correct clevis pin sizes (ms20392 - xxxx), for the Kolb Twinstar Mk3 C please. The current pins fitted bear no resemblance to the "picking list" I have, which gives, (I presume I've got the correct ones), Aileron & flaps - AN394-25 (3C25); wing strut top - AN395-17 (4C17); wing strut at fuselage - AN395-29 (4C29); main wing - AN395-41 (4C41); elevator bottom wires (not a through bolt but a mount on each side), AN393-17 (2C17). The only pin I could find in "The Yellow Book" was the aileron, AN394-29. The pins currently fitted are all 3C (1/4") instead of 5/16". I'm a new owner and I want to change all the clevis pins. Any help will be appreciated. Norman ________________________________ Message 2 _____________________________________ Time: 04:58:10 AM PST US From: Norman Subject: Kolb-List: Mk3 C Clevis Pins Hi again, could someone tell me the correct clevis pin sizes (ms20392 - xxxx), for the Kolb Twinstar Mk3 C please. The current pins fitted bear no resemblance to the "picking list" I have, which gives, (I presume I've got the correct ones), Aileron & flaps - AN394-25 (3C25); wing strut top - AN395-17 (4C17); wing strut at fuselage - AN395-29 (4C29); main wing - AN395-41 (4C41); elevator bottom wires (not a through bolt but a mount on each side), AN393-17 (2C17). The only pin I could find in "The Yellow Book" was the aileron, AN394-29. The pins currently fitted are all 3C (1/4") instead of 5/16". I'm a new owner and I want to change all the clevis pins. Any help will be appreciated. Norman ________________________________ Message 3 _____________________________________ Time: 06:53:02 AM PST US Subject: Kolb-List: New Break-away Tail Wheel From: "KJ4CTZ" Gentlemen, I bought a new breakaway tail wheel from Kolb at Sun N Fun this year. Attempting to replace my original wheel, It appears like the original is JB Welded to the solid aluminum tail rod. What is the recommended procedure for removing the original tail wheel assembly? Read this topic online here: http://forums.matronics.com/viewtopic.php?p=468520#468520 ________________________________ Message 4 _____________________________________ Time: 07:20:49 AM PST US From: william sullivan Subject: Re: Kolb-List: New Break-away Tail Wheel If it's aluminum, heat from a propane torch will break the bond. A wet rag wrapped around the aluminum will keep the heat from traveling up to the tail skeg. Maybe try to twist a bit while heating, so you know when it lets go. It shouldn't take much heat. Or, as suggested earlier this week, cut it off to shorten it a bit. Bill Sullivan Gentlemen, I bought a new breakaway tail wheel from Kolb at Sun N Fun this year. Attempting to replace my original wheel, It appears like the original is JB Welded to the solid aluminum tail rod. What is the recommended procedure for removing the original tail wheel assembly? ________________________________ Message 5 _____________________________________ Time: 07:24:01 AM PST US From: B Young Subject: Re: Kolb-List: Mk3 C Clevis Pins Norman wrote "Hi again, could someone tell me the correct clevis pin sizes (ms20392 - xxxx), for the Kolb Twinstar Mk3 C please" My plans says an395-17 for lift strut attach point to wing An 395-29 for lift strut to cage An394 - 29 flap arm attach and aileron linkage Forward wing attachment an395-45 Wing attach at universal joint are 5/16 bolts Note: AN 39 indicates the style the "5" in an395 is the diameter in 16ths the "dash number# is the length. All clevis pins can be replaced with bolts and locknuts if you don't fold the wings. Disclaimer....... Some of the clevis pins as noted by the plans were very slightly too short. In my humble opinion. If it were me,,, I would measure the distance to be spanned add the thickness of the washers you want to use. Plus a tiny bit so it is not to hard to get together. Boyd Young ________________________________ Message 6 _____________________________________ Time: 07:35:09 AM PST US From: william sullivan Subject: Re: Kolb-List: Mk3 C Clevis Pins Norman- call Aircraft Spruce and get their catalog. Gull of information about sizes, hardness, and strange stuff. Great reference book. Bill Sullivan -------------------------------------------- On Sun, 4/16/17, Norman wrote: Subject: Kolb-List: Mk3 C Clevis Pins To: "Kolb List Posting" Date: Sunday, April 16, 2017, 7:54 AM Hi again, could someone tell me the correct clevis pin sizes (ms20392 - xxxx), for the Kolb Twinstar Mk3 C please. ________________________________ Message 7 _____________________________________ Time: 08:11:46 AM PST US From: George Helton Subject: Re: Kolb-List: New Break-away Tail Wheel A propane torch should do the trick. Just heat it lightly all the way around. It will break loose.Keep wet cloth with around to keep to much heat from transferring to the tail post. Have a great day! > On Apr 16, 2017, at 9:52 AM, KJ4CTZ wrote: > > > Gentlemen, > > I bought a new breakaway tail wheel from Kolb at Sun N Fun this year. Attempting to replace my original wheel, It appears like the original is JB Welded to the solid aluminum tail rod. > > What is the recommended procedure for removing the original tail wheel assembly? > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=468520#468520 > > > > > > > > > ________________________________ Message 8 _____________________________________ Time: 08:58:11 AM PST US Subject: Kolb-List: Re: New Break-away Tail Wheel From: "KJ4CTZ" Thanks guys, I will try mild heat first. If no success I will cut off and put new assembly on. Should it also be JB Welded back on? I assume so but open to suggestions. This forum is great and I appreciate everyone's comments. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=468526#468526 ________________________________ Message 9 _____________________________________ Time: 09:13:06 AM PST US From: william sullivan Subject: Re: Kolb-List: Re: New Break-away Tail Wheel I re-mounted my tail wheel on a very early Firestar because it was crooked. I had the fiberglass rod. I used a 1/4" bolt through it. I was a truck equipment mechanic, so I have a tendency to overdo things a bit. Bill Sullivan -------------------------------------------- On Sun, 4/16/17, KJ4CTZ wrote: Subject: Kolb-List: Re: New Break-away Tail Wheel To: kolb-list@matronics.com Date: Sunday, April 16, 2017, 11:57 AM Thanks guys, I will try mild heat first. If no success I will cut off and put new assembly on. Should it also be JB Welded back on? I assume so but open to suggestions. ________________________________ Message 10 ____________________________________ Time: 03:01:05 PM PST US From: Larry Cottrell Subject: Kolb-List: Fwd: another video and flight ------ Subject: another video and flight The weather was still nice this morning so I put on a lot of clothes and took off. video- https://vimeo.com/213440748 password owyheeflyer Larry -- The older I get, the less tolerant I am of those who are intolerant of others. If you forward this email, or any part of it, please remove my email address before sending. -- The older I get, the less tolerant I am of those who are intolerant of others. If you forward this email, or any part of it, please remove my email address before sending. ________________________________ Message 11 ____________________________________ Time: 03:37:35 PM PST US From: "John Hauck" Subject: RE: Kolb-List: Leading edge bracing; was: Kolb Twinstar (original version) info request Actually, the two 5/16" tubes are fabric braces to keep the fabric from pulling the aluminum rib nose inward. There is no lateral bracing of the leading edge tube except a long 5/16 alum tube that is in compression. The bow tip doesn't do much for lateral bracing of the leading edge tube. That's all you have to keep the rib noses in column. Once they get pulled out of column, they will probably fail. The small 5/16 tubes are flattened, bent, and riveted. They tend to break at this point from vibration with not a whole lot of time on them. I used two 1/2" alum tubes, one inboard and one outboard, diagonally working with each other, attached to the leading edge tube and the main spare. Wish I had a photo of my wing handy. If I can find one I will share it. I may be overly cautious, but it makes me feel more comfortable, especially when I get caught in extremely rough air. Sorry for the delay in responding. Just got home from a 4 day trip. If you need more info, call me. 334-567-6280 john h mkIII Titus, Alabama From: owner-kolb-list-server@matronics.com [mailto:owner-kolb-list-server@matronics.com] On Behalf Of Charlie England Sent: Thursday, April 13, 2017 11:05 AM Subject: Kolb-List: Leading edge bracing; was: Kolb Twinstar (original version) info request John, You mentioned leading edge bracing. This is all I see in the Twinstar I'm restoring. There's nothing along the rest of the leading edge that triangulates/ braces the leading edge. Would you consider this adequate? It's easy to add now, with the cover coming off. Thanks, Charlie Thanks, John. I wasn't sure about how rugged the tubes would be when driving out mandrels, etc. I use similar tricks on the heavier experimentals I've owned. I've got a spring loaded center punch that I ground to a flat nosed, straight shaft, & use it to punch out driven rivets after drilling the heads. I also use small, flush cutting 'dykes' (diagonal wire cutters) to grab pop rivet heads On 4/9/2017 5:58 PM, John Hauck wrote: Charlie E/Kolbers: I have recovered a bunch of them. All that I tore up and a few I didn't. Drilling rivets can be accomplished once you have the mandrels removed. It takes a 1/16" punch, or you can use a pulled mandrel, grind the end flat, hold with vise grips, and knock out with a hammer. The rivet needs to be held to prevent spinning. I grind a V in the end of a hack saw blade with sharp beveled edges. Use that to push up under the rivet to lock it in place while drilling. 4130 airframes should be tube sealed when fabricated. 99% of Kolbs probably have never been tube sealed. Their builders probably never heard of tube sealing. 4130 rusts from inside out if not sealed. That would worry me with an old fuselage, especially a Twinstar. I can't remember exactly what the fuselage looks like other that the root tube that seats and stuff are attached to. This I would make sure is rust free on the inside. I helped Brother Jim rebuild Adriel Heisey's Twinstar, Navajo Nation pilot that shot aerial photos published in Nat Geo and other pubs, that he crashed in a wind storm. It was frightening when we started cutting tubing. Most were rusted well beyond serviceability. Here are photos of his Twinstar: https://uanews.arizona.edu/story/aerial-photos-of-archaeological-sites-on -exhibit-at-state-museum I don't recall anyone flying a free air cooled Rotax on a Kolb successfully. Yours may be an exception. Don't know of any published updates for the Twinstar. It was not a popular model and kits only produced a couple years. Strong lateral bracing of the leading edge of the wing is extremely important to me. Poor/weak lateral bracing can lead to leading edge failure. This causes the Kolb to stop flying immediately. Lower tail post bracing makes it last longer. I don't know a whole lot about the Twinstar. The one Kolb model I never flew. john h mkIII Titus, Alabama -----Original Message----- From: owner-kolb-list-server@matronics.com [mailto:owner-kolb-list-server@matronics.com] On Behalf Of Charlie England Sent: Sunday, April 09, 2017 4:33 PM Subject: Kolb-List: Kolb Twinstar (original version) info request OK, now that I've got that short nose Kolb bit out of my system.... I'm now the proud owner of an N-numbered early Kolb Twinstar (restoration project). IIRC, its serial number is in the low 20's range. A little rusty, but we've peeled the fabric on one wing & the aluminum seems to be in good shape, with very little corrosion, considering that it spent its entire past life in central FL. This one's got a Rotax 503 (converted from single to dual carbs, and to free air cooling) that seems to be in great shape. The previous owner is a close friend who was the builder. I trust what he tells me, and he says that it always cooled fine running it free-air with some added ducting. I'll be replacing hardware, 'soft' parts, etc, but don't intend on doing a showplane restoration; just a safe, nice flying 'after supper' flyer. I've got the plans for the plane, but I'm hoping that you experienced Kolbers can share any suggested mods to these early models, that will make them safer/more durable/etc. Is there a published list of any/all service bulletins or recommended updates? For instance, I've seen the advice to add braces to the tailspring stinger. And I know that the later Twinstars have mass balances on at least some of the control surfaces; is it recommended to add them to the early models? This one does not have any mass balances anywhere. Who's recovered one? Any issues when you drilled out the rivets to remove the ailerons, etc for recovering? Any advice will be appreciated. Thanks, Charlie ________________________________ Message 12 ____________________________________ Time: 03:52:52 PM PST US From: "John Hauck" Subject: RE: Kolb-List: Re: Leading edge bracing; was: Kolb Twinstar (original version) In addition to modifying and additional lateral bracing of the wing's leading edge, I also reinforced my ribs. Makes for an extremely stiff wing. john h mkIII Titus, Alabama -----Original Message----- From: owner-kolb-list-server@matronics.com [mailto:owner-kolb-list-server@matronics.com] On Behalf Of Richard Pike Sent: Thursday, April 13, 2017 9:18 PM Subject: Kolb-List: Re: Leading edge bracing; was: Kolb Twinstar (original version) --> I'm not John, but if you scroll down to page 21 in the MKIII Yellow Book, you will see what Kolb though to be a very useful reinforcement. http://oh2fly.net/oldpoops/Lexan%20rear%20enclosure.html -------- Richard Pike Kolb MKIII N420P (420ldPoops) Kingsport, TN 3TN0 Forgiving is tough. Being forgiven is wonderful. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=468375#468375 ________________________________ Message 13 ____________________________________ Time: 04:10:31 PM PST US From: B Young Subject: Re: Kolb-List: Fwd: another video and flight I like the video. Especially the short approach to the landing.. observation way to many dreaded 3 mile finals. Boyd On Apr 16, 2017 4:02 PM, "Larry Cottrell" wrote: > > ------ > Subject: another video and flight > > > The weather was still nice this morning so I put on a lot of clothes > and took off. > > video- https://vimeo.com/213440748 password owyheeflyer > > > Larry > > -- > The older I get, the less tolerant I am of those who are intolerant of > others. > > If you forward this email, or any part of it, please remove my email > address before sending. > > > -- > The older I get, the less tolerant I am of those who are intolerant of > others. > > If you forward this email, or any part of it, please remove my email > address before sending. > > ________________________________ Message 14 ____________________________________ Time: 04:27:14 PM PST US From: "John Hauck" Subject: RE: Kolb-List: Baby's got some new shoes Sounds good. Reckon sitting more nose high helped with your takeoff? john h mkIII Titus, Alabama -----Original Message----- From: owner-kolb-list-server@matronics.com [mailto:owner-kolb-list-server@matronics.com] On Behalf Of Larry Cottrell Sent: Saturday, April 15, 2017 6:47 PM Subject: Kolb-List: Baby's got some new shoes I finally got my new rims from Matco. They had been on back order for almost a month, at least it seems that way. I had already ordered the 8.50 X 6 tundra tires and tubes. Today dawned cold, 22 degrees but calm for a change. It eventually warmed up to 44 degrees and I went to the hanger to start my tire mounting. I drilled 6 holes in the rims to screw the tires to the rims. The tires fit tight enough that it takes about 20 lbs of air to make them pop out on the rims. That is unlike the Azusa rims that depend on small flanges on the inside of the rims to keep them from spinning. Since I want to run 5 lbs or less I am still not going to take a chance on shearing off the valve stem, thus 6 screws per side. Before I changed from the 8.00 X6 tires, I rolled the plane out and flew all four corners of the compass with a vid camera to monitor my airspeed. The speed averaged out to be about 66 MPH indicated. The same on the ground speed depending on with or against the wind. There was little wind, and my ASI and Ground speed are really close under those conditions. I drilled and cut threads in the rims, and then mounted the tires. Since the 8.00 x 6 tires are on Matco rims as well, I just changed the three bolts that held the bearings in the other tires and changed them to the new tundras. The wind was still holding its breath, so I rolled the plane back out to check the difference. It seems to roll better with the tundra's on it. I taxiied to the other end of the runway, and began my take off. I cannot be sure, but the tires with 5 lbs of air, seemed to bounce a bit on take off, but I could not be sure. When I pulled back on the stick it flew quickly. I tend to push the stick forward to pick up speed, so it could have been trying to fly, while I was pushing it back on the ground. I will be doing a lot more testing when the weather again cooperates. My take off seemed to be quite a bit shorter than normal. In essence there was no indication that my air speed suffered at all. It was quite turbulent so I only made a circuit and half. While I seemed to bounce a bit on take off, I bounced not at all on landing. The tires at 5 lbs are really nice. They appear to not need balancing, unlike the 8.00X6's. Larry -- The older I get, the less tolerant I am of those who are intolerant of others. If you forward this email, or any part of it, please remove my email address before sending. ________________________________ Message 15 ____________________________________ Time: 04:47:38 PM PST US From: "John Hauck" Subject: RE: Kolb-List: Leading edge bracing; was: Kolb Twinstar (original version) info request I left out the fact that the fabric braces are on the nose of the inboard rib. Aft is 4130 and nose is alum tubing. john h From: owner-kolb-list-server@matronics.com [mailto:owner-kolb-list-server@matronics.com] On Behalf Of John Hauck Sent: Sunday, April 16, 2017 5:36 PM Subject: RE: Kolb-List: Leading edge bracing; was: Kolb Twinstar (original version) info request Actually, the two 5/16" tubes are fabric braces to keep the fabric from pulling the aluminum rib nose inward. There is no lateral bracing of the leading edge tube except a long 5/16 alum tube that is in compression. The bow tip doesn't do much for lateral bracing of the leading edge tube. That's all you have to keep the rib noses in column. Once they get pulled out of column, they will probably fail. The small 5/16 tubes are flattened, bent, and riveted. They tend to break at this point from vibration with not a whole lot of time on them. I used two 1/2" alum tubes, one inboard and one outboard, diagonally working with each other, attached to the leading edge tube and the main spare. Wish I had a photo of my wing handy. If I can find one I will share it. I may be overly cautious, but it makes me feel more comfortable, especially when I get caught in extremely rough air. Sorry for the delay in responding. Just got home from a 4 day trip. If you need more info, call me. 334-567-6280 john h mkIII Titus, Alabama From: owner-kolb-list-server@matronics.com [mailto:owner-kolb-list-server@matronics.com] On Behalf Of Charlie England Sent: Thursday, April 13, 2017 11:05 AM Subject: Kolb-List: Leading edge bracing; was: Kolb Twinstar (original version) info request John, You mentioned leading edge bracing. This is all I see in the Twinstar I'm restoring. There's nothing along the rest of the leading edge that triangulates/ braces the leading edge. Would you consider this adequate? It's easy to add now, with the cover coming off. Thanks, Charlie Thanks, John. I wasn't sure about how rugged the tubes would be when driving out mandrels, etc. I use similar tricks on the heavier experimentals I've owned. I've got a spring loaded center punch that I ground to a flat nosed, straight shaft, & use it to punch out driven rivets after drilling the heads. I also use small, flush cutting 'dykes' (diagonal wire cutters) to grab pop rivet heads On 4/9/2017 5:58 PM, John Hauck wrote: Charlie E/Kolbers: I have recovered a bunch of them. All that I tore up and a few I didn't. Drilling rivets can be accomplished once you have the mandrels removed. It takes a 1/16" punch, or you can use a pulled mandrel, grind the end flat, hold with vise grips, and knock out with a hammer. The rivet needs to be held to prevent spinning. I grind a V in the end of a hack saw blade with sharp beveled edges. Use that to push up under the rivet to lock it in place while drilling. 4130 airframes should be tube sealed when fabricated. 99% of Kolbs probably have never been tube sealed. Their builders probably never heard of tube sealing. 4130 rusts from inside out if not sealed. That would worry me with an old fuselage, especially a Twinstar. I can't remember exactly what the fuselage looks like other that the root tube that seats and stuff are attached to. This I would make sure is rust free on the inside. I helped Brother Jim rebuild Adriel Heisey's Twinstar, Navajo Nation pilot that shot aerial photos published in Nat Geo and other pubs, that he crashed in a wind storm. It was frightening when we started cutting tubing. Most were rusted well beyond serviceability. Here are photos of his Twinstar: https://uanews.arizona.edu/story/aerial-photos-of-archaeological-sites-on -exhibit-at-state-museum I don't recall anyone flying a free air cooled Rotax on a Kolb successfully. Yours may be an exception. Don't know of any published updates for the Twinstar. It was not a popular model and kits only produced a couple years. Strong lateral bracing of the leading edge of the wing is extremely important to me. Poor/weak lateral bracing can lead to leading edge failure. This causes the Kolb to stop flying immediately. Lower tail post bracing makes it last longer. I don't know a whole lot about the Twinstar. The one Kolb model I never flew. john h mkIII Titus, Alabama -----Original Message----- From: owner-kolb-list-server@matronics.com [mailto:owner-kolb-list-server@matronics.com] On Behalf Of Charlie England Sent: Sunday, April 09, 2017 4:33 PM Subject: Kolb-List: Kolb Twinstar (original version) info request OK, now that I've got that short nose Kolb bit out of my system.... I'm now the proud owner of an N-numbered early Kolb Twinstar (restoration project). IIRC, its serial number is in the low 20's range. A little rusty, but we've peeled the fabric on one wing & the aluminum seems to be in good shape, with very little corrosion, considering that it spent its entire past life in central FL. This one's got a Rotax 503 (converted from single to dual carbs, and to free air cooling) that seems to be in great shape. The previous owner is a close friend who was the builder. I trust what he tells me, and he says that it always cooled fine running it free-air with some added ducting. I'll be replacing hardware, 'soft' parts, etc, but don't intend on doing a showplane restoration; just a safe, nice flying 'after supper' flyer. I've got the plans for the plane, but I'm hoping that you experienced Kolbers can share any suggested mods to these early models, that will make them safer/more durable/etc. Is there a published list of any/all service bulletins or recommended updates? For instance, I've seen the advice to add braces to the tailspring stinger. And I know that the later Twinstars have mass balances on at least some of the control surfaces; is it recommended to add them to the early models? This one does not have any mass balances anywhere. Who's recovered one? Any issues when you drilled out the rivets to remove the ailerons, etc for recovering? Any advice will be appreciated. Thanks, Charlie ________________________________ Message 16 ____________________________________ Time: 04:53:43 PM PST US From: Larry Cottrell Subject: Re: Kolb-List: Baby's got some new shoes On Sun, Apr 16, 2017 at 5:27 PM, John Hauck wrote: > > Sounds good. > > Reckon sitting more nose high helped with your takeoff? I think that it did, seems a lot shorter. I just went back and looked at the video and as near as I can tell I lifted off at 34 MPH indicated. Stall is 29-30 . With the taller tires it is sitting at the angle that it is when it actually stalls, so it would appear to be at optimum attitude. I am experiencing some bouncing at the same time that it wants to fly. Not sure if it is dribbling or, starting to bounce. Need more take off's to tell. Actually an observer would be just the thing. Larry ________________________________ Message 17 ____________________________________ Time: 05:00:40 PM PST US Subject: Re: Kolb-List: Baby's got some new shoes From: Russ Kinne Hey, Larry, you got an interesting problem. Id be gad to observe & photograph your TOs Just pay my travel from Maine! Fair winds, Russ K > On Apr 16, 2017, at 7:53 PM, Larry Cottrell wrote: > > > On Sun, Apr 16, 2017 at 5:27 PM, John Hauck wrote: >> >> Sounds good. >> >> Reckon sitting more nose high helped with your takeoff? > > > I think that it did, seems a lot shorter. I just went back and looked > at the video and as near as I can tell I lifted off at 34 MPH > indicated. Stall is 29-30 . With the taller tires it is sitting at the > angle that it is when it actually stalls, so it would appear to be at > optimum attitude. > > I am experiencing some bouncing at the same time that it wants to fly. > Not sure if it is dribbling or, starting to bounce. Need more take > off's to tell. Actually an observer would be just the thing. > > Larry > > > ________________________________ Message 18 ____________________________________ Time: 05:15:58 PM PST US From: Larry Cottrell Subject: Re: Kolb-List: Baby's got some new shoes Hey, Larry, you got an interesting problem. Id be gad to observe & photograph your TOs Just pay my travel from Maine! Fair winds, Russ K Sounds good, but after buying all those rims, tires and tubes, my slush fund is a bit under the weather. However if you toss your stuff in your plane and start out now, you could be here in a week or two. Larry ________________________________ Message 19 ____________________________________ Time: 05:25:50 PM PST US From: Russ Kinne Subject: Re: Kolb-List: Baby's got some new shoes Would love to fly out to you but I=99m plane-less at the mo. Have made 6 coast-coast trips in Cessnas, GREAT fun & would love to do another. I=99ll work on the Lotto Good luck, Russ > On Apr 16, 2017, at 8:15 PM, Larry Cottrell wrote: > > > > Hey, Larry, you got an interesting problem. I=99d be gad to observe & > photograph your TO=99s > Just pay my travel from Maine! > Fair winds, > Russ K > > Sounds good, but after buying all those rims, tires and tubes, my > slush fund is a bit under the weather. However if you toss your stuff > in your plane and start out now, you could be here in a week or two. > Larry > > > > ________________________________ Message 20 ____________________________________ Time: 05:50:59 PM PST US From: "John Hauck" Subject: RE: Kolb-List: Baby's got some new shoes Maybe you are trying to make the airplane fly too soon. Keep the nose down until you get well stall, then pull the nose up. It gets light, but not light enough to fly. 5 psi in big tires have a lot of reflex. Just the thoughts of a guy that has never flown anything bigger than an 8x6, which seemed huge for a short time after upsizing from 6x6. Now they are just regular tires. john h mkIII Titus, Alabama -----Original Message----- From: owner-kolb-list-server@matronics.com [mailto:owner-kolb-list-server@matronics.com] On Behalf Of Larry Cottrell Sent: Sunday, April 16, 2017 6:53 PM Subject: Re: Kolb-List: Baby's got some new shoes --> On Sun, Apr 16, 2017 at 5:27 PM, John Hauck wrote: > > Sounds good. > > Reckon sitting more nose high helped with your takeoff? I think that it did, seems a lot shorter. I just went back and looked at the video and as near as I can tell I lifted off at 34 MPH indicated. Stall is 29-30 . With the taller tires it is sitting at the angle that it is when it actually stalls, so it would appear to be at optimum attitude. I am experiencing some bouncing at the same time that it wants to fly. Not sure if it is dribbling or, starting to bounce. Need more take off's to tell. Actually an observer would be just the thing. Larry ________________________________ Message 21 ____________________________________ Time: 06:03:03 PM PST US Subject: Re: Kolb-List: Leading edge bracing; was: Kolb Twinstar (original version) info request From: Charlie England You're right about the little tubes cracking. One of my wing leading edge tubes had some corrosion & a big crack about half way around it near the root rib. After drilling it free, the diagonal tube tying it to the main spar showed cracks in the bends on both ends. I'll be adding new diagonals, either of larger aluminum, or some 4130 tubes the same size. (Easier to form safely, by using a little heat.) Thanks for the addtl info. You may well get a call from me before this project is finished. :-) Charlie On 4/16/2017 5:35 PM, John Hauck wrote: > > Actually, the two 5/16" tubes are fabric braces to keep the fabric > from pulling the aluminum rib nose inward. There is no lateral > bracing of the leading edge tube except a long 5/16 alum tube that is > in compression. > > The bow tip doesn't do much for lateral bracing of the leading edge > tube. That's all you have to keep the rib noses in column. Once they > get pulled out of column, they will probably fail. > > The small 5/16 tubes are flattened, bent, and riveted. They tend to > break at this point from vibration with not a whole lot of time on them. > > I used two 1/2" alum tubes, one inboard and one outboard, diagonally > working with each other, attached to the leading edge tube and the > main spare. Wish I had a photo of my wing handy. If I can find one I > will share it. > > I may be overly cautious, but it makes me feel more comfortable, > especially when I get caught in extremely rough air. > > Sorry for the delay in responding. Just got home from a 4 day trip. > > If you need more info, call me. 334-567-6280 > > john h > > mkIII > > Titus, Alabama > > *From:*owner-kolb-list-server@matronics.com > [mailto:owner-kolb-list-server@matronics.com] *On Behalf Of *Charlie > England > *Sent:* Thursday, April 13, 2017 11:05 AM > *To:* kolb-list@matronics.com > *Subject:* Kolb-List: Leading edge bracing; was: Kolb Twinstar > (original version) info request > > John, > > You mentioned leading edge bracing. This is all I see in the Twinstar > I'm restoring. There's nothing along the rest of the leading edge that > triangulates/ braces the leading edge. > > Would you consider this adequate? It's easy to add now, with the cover > coming off. > > Thanks, > > Charlie > > Thanks, John. I wasn't sure about how rugged the tubes would be when > driving out mandrels, etc. I use similar tricks on the heavier > experimentals I've owned. I've got a spring loaded center punch that I > ground to a flat nosed, straight shaft, & use it to punch out driven > rivets after drilling the heads. I also use small, flush cutting > 'dykes' (diagonal wire cutters) to grab pop rivet heads > > On 4/9/2017 5:58 PM, John Hauck wrote: > > > Charlie E/Kolbers: > > I have recovered a bunch of them. All that I tore up and a few I didn't. > > Drilling rivets can be accomplished once you have the mandrels removed. It takes a 1/16" punch, or you can use a pulled mandrel, grind the end flat, hold with vise grips, and knock out with a hammer. The rivet needs to be held to prevent spinning. I grind a V in the end of a hack saw blade with sharp beveled edges. Use that to push up under the rivet to lock it in place while drilling. > > 4130 airframes should be tube sealed when fabricated. 99% of Kolbs probably have never been tube sealed. Their builders probably never heard of tube sealing. 4130 rusts from inside out if not sealed. That would worry me with an old fuselage, especially a Twinstar. I can't remember exactly what the fuselage looks like other that the root tube that seats and stuff are attached to. This I would make sure is rust free on the inside. > > I helped Brother Jim rebuild Adriel Heisey's Twinstar, Navajo Nation pilot that shot aerial photos published in Nat Geo and other pubs, that he crashed in a wind storm. It was frightening when we started cutting tubing. Most were rusted well beyond serviceability. Here are photos of his Twinstar: > > https://uanews.arizona.edu/story/aerial-photos-of-archaeological-sites-on-exhibit-at-state-museum > > I don't recall anyone flying a free air cooled Rotax on a Kolb successfully. Yours may be an exception. > > Don't know of any published updates for the Twinstar. It was not a popular model and kits only produced a couple years. > > Strong lateral bracing of the leading edge of the wing is extremely important to me. Poor/weak lateral bracing can lead to leading edge failure. This causes the Kolb to stop flying immediately. > > Lower tail post bracing makes it last longer. > > I don't know a whole lot about the Twinstar. The one Kolb model I never flew. > > john h > > mkIII > > Titus, Alabama > > -----Original Message----- > > From:owner-kolb-list-server@matronics.com > [mailto:owner-kolb-list-server@matronics.com] On Behalf Of Charlie England > > Sent: Sunday, April 09, 2017 4:33 PM > > To:kolb-list@matronics.com > > Subject: Kolb-List: Kolb Twinstar (original version) info request > > > OK, now that I've got that short nose Kolb bit out of my system.... > > I'm now the proud owner of an N-numbered early Kolb Twinstar (restoration project). IIRC, its serial number is in the low 20's range. > > A little rusty, but we've peeled the fabric on one wing & the aluminum seems to be in good shape, with very little corrosion, considering that it spent its entire past life in central FL. > > This one's got a Rotax 503 (converted from single to dual carbs, and to free air cooling) that seems to be in great shape. The previous owner is a close friend who was the builder. I trust what he tells me, and he says that it always cooled fine running it free-air with some added ducting. > > I'll be replacing hardware, 'soft' parts, etc, but don't intend on doing a showplane restoration; just a safe, nice flying 'after supper' flyer. > > I've got the plans for the plane, but I'm hoping that you experienced Kolbers can share any suggested mods to these early models, that will make them safer/more durable/etc. Is there a published list of any/all service bulletins or recommended updates? For instance, I've seen the advice to add braces to the tailspring stinger. And I know that the later Twinstars have mass balances on at least some of the control surfaces; is it recommended to add them to the early models? This one does not have any mass balances anywhere. > > Who's recovered one? Any issues when you drilled out the rivets to remove the ailerons, etc for recovering? > > Any advice will be appreciated. > > Thanks, > > Charlie > --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ________________________________ Message 22 ____________________________________ Time: 06:09:05 PM PST US Subject: Re: Kolb-List: Re: Leading edge bracing; was: Kolb Twinstar (original version) From: Charlie England Thanks, Richard; I'll look at doing that mod, as well. BTW, my plans just mention '1/8 x 1/8 pop rivets'. What's the rivet of choice? Just a typical 18-8 stainless, or 304 stainless? the 316 stainless are pricey enough that enough to do the whole plane might cost as much as the whole kit. :-) Charlie On 4/13/2017 9:17 PM, Richard Pike wrote: > > I'm not John, but if you scroll down to page 21 in the MKIII Yellow Book, you will see what Kolb though to be a very useful reinforcement. > http://oh2fly.net/oldpoops/Lexan%20rear%20enclosure.html > > -------- > Richard Pike > Kolb MKIII N420P (420ldPoops) > Kingsport, TN 3TN0 > > Forgiving is tough. Being forgiven is wonderful. > --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ________________________________ Message 23 ____________________________________ Time: 06:10:47 PM PST US From: "John Hauck" Subject: RE: Kolb-List: Baby's got some new shoes I'm tired and can't type. I meant to say "keep the nose down until you get well "above" stall." john h mkIII Titus, Alabama -----Original Message----- From: owner-kolb-list-server@matronics.com [mailto:owner-kolb-list-server@matronics.com] On Behalf Of John Hauck Sent: Sunday, April 16, 2017 7:51 PM Subject: RE: Kolb-List: Baby's got some new shoes Maybe you are trying to make the airplane fly too soon. Keep the nose down until you get well stall, then pull the nose up. It gets light, but not light enough to fly. 5 psi in big tires have a lot of reflex. Just the thoughts of a guy that has never flown anything bigger than an 8x6, which seemed huge for a short time after upsizing from 6x6. Now they are just regular tires. john h mkIII Titus, Alabama -----Original Message----- From: owner-kolb-list-server@matronics.com [mailto:owner-kolb-list-server@matronics.com] On Behalf Of Larry Cottrell Sent: Sunday, April 16, 2017 6:53 PM Subject: Re: Kolb-List: Baby's got some new shoes --> On Sun, Apr 16, 2017 at 5:27 PM, John Hauck wrote: > > Sounds good. > > Reckon sitting more nose high helped with your takeoff? I think that it did, seems a lot shorter. I just went back and looked at the video and as near as I can tell I lifted off at 34 MPH indicated. Stall is 29-30 . With the taller tires it is sitting at the angle that it is when it actually stalls, so it would appear to be at optimum attitude. I am experiencing some bouncing at the same time that it wants to fly. Not sure if it is dribbling or, starting to bounce. Need more take off's to tell. Actually an observer would be just the thing. Larry ________________________________ Message 24 ____________________________________ Time: 06:19:39 PM PST US From: Larry Cottrell Subject: Re: Kolb-List: Baby's got some new shoes Maybe you are trying to make the airplane fly too soon. Keep the nose down until you get well stall, then pull the nose up. --------------------------------------------------------------------------------------------------------------------------- Actually it was the "bouncing" that prompted me to pull it up. Something similar happened on the first take off, so I was prepared for it. Just don't know what causes it. I am wondering if a bit more air might clear it up. The first time I can fly, I will set another camera up to film the take off as it happens from in front. It is nothing more than a curious occurrence. Larry ________________________________ Message 25 ____________________________________ Time: 06:30:18 PM PST US From: George Helton Subject: Re: Kolb-List: Re: New Break-away Tail Wheel Heat will definitely break JB weld loose. I actually just replaced the tailw heel on my Firestar 1 with the new Kolb breakaway unit. I had drill out the f iberglass tail strut which was a real pain, but JB had failed at tailwheel a ssembly. So I installed a new T7075 tail strut. I just locked it into lower vertical stabilizer with a single bolt at both ends. Here's a couple of pic tures. I did coat the inside of both end with a liberal amount of white silicon to s eal out moisture. George H. Firestar 1, #FS100 14GDH Mesick, MI Have a great day! > On Apr 16, 2017, at 11:57 AM, KJ4CTZ wrote: > > > Thanks guys, > > I will try mild heat first. If no success I will cut off and put new assem bly on. > > Should it also be JB Welded back on? I assume so but open to suggestions. > > This forum is great and I appreciate everyone's comments. > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=468526#468526 > > > > > > ========================== ========= ========================== ========= ========================== ========= ========================== ========= ========================== ========= > > > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message kolb-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Kolb-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/kolb-list Browse Digests http://www.matronics.com/digest/kolb-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.