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Re: Replace steel tubes with carbon?
I agree with Sam. Dissimilar electric potential between materials with an electrolyte like dirty water creates a battery.
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Iron besides rusting has an electronegative value of 1.8 and Al 1.613 a difference of 0.2 with iron being the cathode and aluminum turning to white powder. Carbon’s electronegative value is 2.55 and Al 1.613 a difference of 0.937 with carbon being the cathode. The Aluminum will corrode 4.6 time faster electrically coupled to carbon. I had to cut the elevators off my Dragonfly with a hacksaw when the prop hub failed at Torrance. Charlie My you tube channel
On Monday, May 9, 2022, 2:02 PM, Sam Hoskins <sam.hoskins@...> wrote:
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Re: Replace steel tubes with carbon?
Richard LaBarre
Always get a kick out of brakes and breaks.
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On May 9, 2022, at 2:51 PM, Robert Schmid <robert@...> wrote:
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Re: LS1 midspan hinge repair
Vern,
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I do not have Q plans. From the discussion I surmise an Aluminum arm is bonded to the canard and it failed in fatigue between the hinge at the huge change in stiffness where it is bonded in. Stress follows stiffness change. I chimed in because I seem to remember an accident where this might have been a factor in a inflight elevator failure. I cannot remember details. Fatigue failures are insidious and sadly not considered in plastic airplanes not designed to last a half century. My 767 door springs had to demonstrate 200,000 cycles to qualify. How much testing did the Q Corp do on hinge arms? For your somewhat off topic question. Dragonfly has tip bearing, 2 mid span hinge arms 4130 steel bonded in and the elevator torque control tube is coaxial and plugs into the elevator hinge tube. Torque loads are transmitted through the Revised bonded in wood rib with a bellcrank and two bolts directly to the skin laminate. The Dragonfly elevator flutter issue was using -3 bolts to pin the aluminum hinge tube to the steel elevator control tube in the fuselage that was also pinned together with -3 bolts. The only thing between the hinge tube and elevator skin, 2 lb styrofoam. When things got shaking the bearing strength of the hinge tube was not enough to keep the holes from elongating allowing flutter. No one lost a fluttering elevator which at least took the hinge joints to limit loads. Regards,
On Monday, May 9, 2022, 12:42 PM, Frankenbird Vern <smeshno1@...> wrote:
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Re: Replace steel tubes with carbon?
No, no, no. The steel is just fine. Just don't keep your finished bird unattended in the elements for 10 years. Do an annual condition inspection, lubricate annually, and the steel tubes will be just fine. Sam
On Mon, May 9, 2022 at 1:51 PM Robert Schmid <robert@...> wrote: Given my rescue project was sitting outside for a while, some of the steel tubes/connecting rods are corroded and I am inspecting them all. Some of them I had to cut already so I am wondering if replacing steel connecting rods with carbon tubes is a good idea.
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Re: Quickie Part Specs & Details
Chris Walterson
Robert-------------- Have you seen all the video of the various builds that Sam has made? There are several of us and some interesting mods. I am not saying to do it, but if you watch my video you will see how I set up my ailerons.
Simple and easily removed, but I did build mine from scratch and have a central hinge on the aileron. If you are real handy you could do a retrofit with your existing aileron. Whatever you decide, enjoy the ride.----------------- Chris -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
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Re: LS1 midspan hinge repair
David J. Gall
See if what you need is in this .ZIP file.
On May 9, 2022, at 1:03 PM, Chris Walterson <dkeats@...> wrote:
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Re: LS1 midspan hinge repair
Chris Walterson
I was building from scratch so I installed 2 equilly placed hinge points rather than the 1 central one. I have a inboard gear so there is no load on the hinge rather than elevator load . If your wheels are at the canard tip, the hinge will take pressure when landing if there isn't enough play built in.
take care------------ Chris -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
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Re: LS1 midspan hinge repair
Charlie.. do our Dragonfly Canards share this issue? If so then I'll be modifying. I figured it was fatigue..and probably from propeller thrust
variations. Just my guess as to why. First thing that came to mind was adding doublers but I'll look at Jay's solution. My canard has not flown,
but the hinges are installed. I will be building both elevators new.
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of One Sky Dog via groups.io <Oneskydog@...>
Sent: Monday, May 9, 2022 7:20 AM To: main@Q-List.groups.io <main@Q-List.groups.io> Subject: Re: [Q-List] LS1 midspan hinge repair Vern,
These center hinges have failed before. Steel is a lot better in fatigue than Al but if the inflight stress levels are close to the limit it is an insidious problem. It is obviously not a shear failure of they would be breaking upon loading.
Reducing stress is the only answer. This is a materials problem. Either increase cross section, increase load transfer points, or redesign like Jay has done. Fatigue = repeated cyclic loading below the yield point internal material flaws move to high stress areas over time resulting in cracks and final failure at loads below the design point. My $0.02 worth of armchair analysis.
Regards,
Charlie
My you tube channel
On Monday, May 9, 2022, 4:47 AM, Frankenbird Vern <smeshno1@...> wrote:
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Re: LS1 midspan hinge repair
Thanks Jim Its on my schedule as an annual check item, along with
greasing the hinges and checking the pins. I do the check looking for movement at the hinge as a confidence improver on the Pre-taxi. (That will be a Preflight whenever it gets that far).
I take it the mags are not removed due to the AV30 install? Rich
On 09/05/2022 17:12, Jim Patillo wrote:
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Re: Quickie Part Specs & Details
OK, I get it now. If that works, no new ailerons required. I would only caution again not to get the part too hot. The aluminum will transfer heat directly to the foam and you don’t want to damage the foam and/or the epoxy. Good luck.
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Robert Schmid
Sent: Monday, May 9, 2022 12:30 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Quickie Part Specs & Details
Bad explanation on my part I am sure … Yes we cut the connecting CS11 right at the 1in spacer, and now the connecting rod is stuck inside the aileron torque tube. But I figured we can carefully drill the remaining couple inches of the connecting rod out of the torque tube and save the aileron … start with 1/2 bit and work our way slowly up to where the inside brakes loose.
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Replace steel tubes with carbon?
Given my rescue project was sitting outside for a while, some of the steel tubes/connecting rods are corroded and I am inspecting them all. Some of them I had to cut already so I am wondering if replacing steel connecting rods with carbon tubes is a good idea.
Quickie brain trust … What are your thoughts? Replacing steel with carbon? And yes I know, I still need to watch corrosion due to dislike conductive materials. -- Robert "TheFrisco" Schmid (408) 805-5450 www.facebook.com/TheFlyingFriscos www.theflyingfriscos.com Love building planes almost as much as flying. Latest completed build is "Loki", a Chinook Plus 2 bush plane.
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Re: Quickie Part Specs & Details
Bad explanation on my part I am sure … Yes we cut the connecting CS11 right at the 1in spacer, and now the connecting rod is stuck inside the aileron torque tube. But I figured we can carefully drill the remaining couple inches of the connecting rod out of the torque tube and save the aileron … start with 1/2 bit and work our way slowly up to where the inside brakes loose.
Does that make sense? -- Robert "TheFrisco" Schmid (408) 805-5450 www.facebook.com/TheFlyingFriscos www.theflyingfriscos.com Love building planes almost as much as flying. Latest completed build is "Loki", a Chinook Plus 2 bush plane.
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Re: Quickie Part Specs & Details
Hi Robert,
If you are wondering about the original kit parts, you can look at the following document of mine: http://n8wq.scheevel.com/documents/build_logs/01_N8WQ-log_Preliminary_Inventory_Purchase_Records.pdf
The steel tubing parts are listed in the shipping checklists (an excerpt from above document). The 72” long 5/8” tubing shown below is what was used for the torque tubes in the ailerons and elevators.
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Robert Schmid
Sent: Monday, May 9, 2022 11:58 AM To: main@Q-List.groups.io Subject: Re: [Q-List] Quickie Part Specs & Details
Jay - I am confused. Why would I make new ailerons when all I need is the connector rod between the ailerons and the controls inside the fuselage? What am I missing?
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Re: Quickie Part Specs & Details
I thought you said you had to cut them off and leave the steel in the aileron torque tube…What am I missing?
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Robert Schmid
Sent: Monday, May 9, 2022 11:58 AM To: main@Q-List.groups.io Subject: Re: [Q-List] Quickie Part Specs & Details
Jay - I am confused. Why would I make new ailerons when all I need is the connector rod between the ailerons and the controls inside the fuselage? What am I missing?
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Re: Quickie Part Specs & Details
Jay - I am confused. Why would I make new ailerons when all I need is the connector rod between the ailerons and the controls inside the fuselage? What am I missing?
What I am looking for is specs on the metal parts, type, wall thickness, length etc. Thanks Robert -- Robert "TheFrisco" Schmid (408) 805-5450 www.facebook.com/TheFlyingFriscos www.theflyingfriscos.com Love building planes almost as much as flying. Latest completed build is "Loki", a Chinook Plus 2 bush plane.
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Re: Quickie Part Specs & Details
Michael Dunning
And thanks to Sam Hoskins there is a way better set of photo instructions to follow now, if you do make new ones!
LS(1) 0417 MOD CANARD INSTRUCTIONS Epoxy Wipe for Composite Aircraft Finishing -- -MD #2827 (still thinking about planning on visualizing how to finish building)
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Re: Quickie Part Specs & Details
Hi Robert,
Of all of the flying surfaces, the ailerons are probably the easiest to build. Maybe it would be best to build new ones and go from there. The materials are all available from spruce and the hotwire is easy to make from hardware store materials. You can probably recover the internal parts (QCSM-7’s) from the scrap ailerons, so no need to make those.
Including reading and comprehending the plans for the project, setting up the table and making the parts, it is probably a 3-weekend project to build new ailerons (not counting filling and finishing). My two cents.
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Robert Schmid
Sent: Monday, May 9, 2022 9:29 AM To: main@Q-List.groups.io Subject: [Q-List] Quickie Part Specs & Details
So my aileron connection tube CS11 is bye bye, corroded and needed to be cut into pieces to get the ailerons out. And yes I could just use my calipers and measure it out but I was wondering ... Is there a parts list of the various items with specs, sizes etc? I am looking for motor mount drawings as well, so there is a few of them.
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Re: LS1 midspan hinge repair
Richard, I do that same check but simply pushing up and down on the mid point may not tell the whole story. If the elevator slot and elevator fit closely, there may not be enough room to fully check the movement up and down. That’s why it’s
a good idea to check this at yearly inspection.
Don’t know if the plane was flown here with the mid pivot gone or not. Don’t know if the elevator delay took place in flight or not.
Jim
N46JP Q200
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Richard Thomson <richard@...>
Sent: Monday, May 9, 2022 8:58:24 AM To: main@Q-List.groups.io <main@Q-List.groups.io> Subject: Re: [Q-List] LS1 midspan hinge repair So had Mike flown with this broken support and not realised, or had it broken on the ground ?
Could the delam on the elevator have been caused by flexing in flight after it failed?
On my walk around I do a check of the mid point support by gently looking for up and down movement.
This was suggested by somebody on this list a long time ago and seemed a sensible check to have on my list. But I do like Jays solution, its solid. Looks like it could be retrofitable. its on my list of improvements.
Rich T
On 09/05/2022 15:23, Jim Patillo wrote:
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Re: LS1 midspan hinge repair
So had Mike flown with this broken support and not realised,
or had it broken on the ground ? Could the delam on the elevator have been caused by flexing
in flight after it failed? On my walk around I do a check of the mid point support by
gently looking for up and down movement. This was suggested by somebody on this list a long time ago
and seemed a sensible check to have on my list. But I do like Jays solution, its solid. Looks like it could
be retrofitable. its on my list of improvements.
Rich T
On 09/05/2022 15:23, Jim Patillo wrote:
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Quickie Part Specs & Details
So my aileron connection tube CS11 is bye bye, corroded and needed to be cut into pieces to get the ailerons out. And yes I could just use my calipers and measure it out but I was wondering ... Is there a parts list of the various items with specs, sizes etc? I am looking for motor mount drawings as well, so there is a few of them.
I purchased the full set of plans from https://www.canardzone.com/store/product/9-q2-q-200-construction-plans/?ct=1652110002 but its missing details which I was hoping you have or have seen somewhere. Thanks Robert -- Robert "TheFrisco" Schmid (408) 805-5450 www.facebook.com/TheFlyingFriscos www.theflyingfriscos.com Love building planes almost as much as flying. Latest completed build is "Loki", a Chinook Plus 2 bush plane.
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