Step 2, Build Magnum!!

201 posts in this topic

Posted

Got back to work on the Magnum today. I worked on fabricating the trim tab for the rudder. Seems that the Avid factory decided to weld mine solid to the rudder, so I had to cut it off and weld it to a piece of 3/8" square tubing that I had to special order from ACS.....then fabricate an adjustment tab for the tab and install the hinge.  After that (which took most of the day) I started working on the wings again.  I epoxied in the tubes that will hold the 6 false ribs where the tip tanks would have went. Tomorrow I hope to Hysol in the false ribs.

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Posted

Looks good Barry!  I like the left only trim tab! I might have to change mine....

Ron

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Posted

Barry,  Do you have the fiberglass boot cowl for your Magnum?  EDMO

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Posted

Ed, I do have them. 

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Posted

Today I installed one set of false ribs on one wing where the tip tanks would have gone and prepped the second wing for the same in the morning. Installed the angle braces to the outer ribs. Studied the build manual and confused myself even more............Does anyone know if there is a "root rib" ?   The plans show it labeled as such, but I think they are talking about the trailing rib that goes on the rear spar and glues onto the fuel tank?  Any pictures anybody has of this area and time of their build is appreciated :)

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Posted

Barry, you are correct it is the rear part of the rib glued to the back of the fuel tank...

Welcome to the Magnum Manual Land of confusion!

Ron

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Posted

Thanks Ron! Also, the ribs do not fit over the tank, the fiberglass is too wide for the rib.  I will post a picture of that soon, but it looks like the rib will need to be cut or the tank ground down (ikes) to make it fit?

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Posted

I think I know what you are saying...I’ll attach a pic...

9C25E96C-72E6-4B7E-B092-55C5D2513FB6.thuNot from my bird, but it is the second Magnum built by Avid.

The ribs are sunken into the tank...the PO had done this step already when I bought it, so I’m not much help in the how to area...

Another thing worthy of mention in the pic is that they did not wrap these tanks with fiberglass!  You will have to fit the ribs after wrapping fiberglass over the tank and spars.

Maybe somebody, that has actually done this can jump in here?

I did a whole lot of filling and sanding to get that area smooth so that part of a rib wouldn’t stick out.

Thanks,

Ron

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Posted

Thanks for the picture Ron. I have posted to the group for more information. I think the ribs will need glued on first, then the glass wrap. Just need to get the ribs fitted right. I thought you said this kit was easy? Ha! And also I love the detailed manual;))

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Posted

It’ easy once you get tired of the manual and pitch it in the trash :lmao:

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Posted

Today I balanced the rudder and epoxied 3 more false ribs on the other wing. A second coat of poly on the false ribs. My used engine also showed up!

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Posted

Today, with my friends Ralph and Rick, we mounted the wings to the fuselage so I could mount the fuel tanks and the rest of the ribs. Sanded and leaked checked the fuel tanks and repaired various leaks.

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Posted

WOW ... LOOKING AWESOME.  THANK YOU for sharing the photos.  Very inspirational and motivational.  Helps the rest of us who are building / modifing and repairing  focused and on track.   Can't wait to see future updates.   Two thumbs up.

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Posted

Thanks Brian, I get a lot of help from others and their posts here too, hope my posts help the next builder out!

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Posted

Today I installed the final false ribs near the fuel tanks, then fitted the 4 trailing ribs that are epoxied to the fuel tanks and rear spars. Nothing fits very good and the indentations in the fuel tanks are in the wrong locations, so modifications to the ribs are necessary. There are a LOT of missing instruction in the build manual, so some fabrication is necessary and some of the parts are not produced with much precision (mostly fiberglass issues), but for the most part it is going together fairly smooth. I also ran in to a snag with the rib spacing. The previous owner was off about 1/2" and the root rib is going to have to be 1/2" too far towards the fuselage, but it should be okay.

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Posted

Very important thing with the rib spacing is that the long tails (flaperon hangers) line up with the flaperons.  What is the rib spacing on your plane?  How many flaperon hangers on each wing?  (still wondering about those "Kitfox 4" wings for sale)  JImChuk

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Posted

Jim, that is defiantly an important measurement. I actually clamped my flaperons on last night before gluing the ribs. The fabulous manual does actually tell us to do this prior (during) setting the final ribs to the tank. One thing to make mention of is that the wing drawing has the root rib flush with the wing tank. This is wrong, the root rib must be 1/2" past the wing tank towards the fuselage for the root  flaperon hing to line up. The rib spacing is just as the plans describe with 7 attach points for the flap hinges. 11 13/16" rib spacing and 23 11/16" between the long ribs.

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Posted (edited)

7 attach points for flap hinges?  Jim said that the Avid wings we have been looking at that were advertised as Kitfox wings have 6 long rib tails, or attach points?  ???  Normal Kitfox has 5.  Sorry for mixing that in with your build posts, but that might mean something?   Catalina Wings?   EDMO

Edited by EDMO

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Posted

Yes, 7 attach points, 7 long ribs.

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Posted

Today we attached the ribs behind the left fuel tank and installed the jury strut mounts. Then set up the ribs and jigging for the right wing ribs behind the fuel tank.

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Posted (edited)

I had the Avid Magnum manual for a while - I have never understood why they want to wrap another layer of fiberglass over the fiberglass tanks?  Kitfox just uses GE Silicone II to glue the tank to the spars, and some of us put a capstrip over/under the tank to match the false rib tails.  Maybe it is because the Avid tank fuel filler openings are different?   EDMO

Edited by EDMO

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Posted

Ed,

All I can figure is the tanks are pretty thin and it helps to strengthen them and prevent future leaks.  I am new to this type of build (I normally work with aluminum) so I am just doing as the manual and others have done. However, I will be looking for fiberglass mat that is clean and easy to lay down to try to minimize the weight and also the finish work after.  P.S. the USPS lost those LED lights, seems they delivered them to the wrong mail box and someone kept them.  Still waiting for them to find them.......argh......

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Posted (edited)

Ed,

All I can figure is the tanks are pretty thin and it helps to strengthen them and prevent future leaks.  I am new to this type of build (I normally work with aluminum) so I am just doing as the manual and others have done. However, I will be looking for fiberglass mat that is clean and easy to lay down to try to minimize the weight and also the finish work after.  P.S. the USPS lost those LED lights, seems they delivered them to the wrong mail box and someone kept them.  Still waiting for them to find them.......argh......

Oh - Bullshit!  Not the first time they have lost something for me.  They had some insurance on them - Forget how much - Bummer!  Keep me posted - I might file a claim - again!  They had tracking too.   I haven't cashed your check.   I don't have any more and don't know if I can get more.  I do have some Grimes with a strobe lens added to them that you could possibly put the Spruce 30 watt LED bulbs in and it should give you some sort of strobe, or buy a power pack to match them, but no tail lights in them.   EDMO

Edited by EDMO

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Posted

I will keep you posted Ed, maybe they will show up soon. I will give it a couple more days.........thanks.

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Posted (edited)

I will keep you posted Ed, maybe they will show up soon. I will give it a couple more days.........thanks.

I will do my best to make it right for you.  Sorry, I sure thought you would get them since its not close to Christmas rush.  I will hold your check until you let me know something.    I have the receipt showing $50 insurance on them.   EDMO

Edited by EDMO

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