ICM AH-1G 68-15012 "#1 Du Me Mi" - F Troop, 4th Cav, Phu Bai, 1972 (mostly) Finished!

[Citadelgrad]

Oh, man, that sucks.  But I instantly thought, better now than after painting.  

 

You got this!

[Out2gtcha]

Thanks!

I'm hoping my idea works, otherwise I might be waiting for @Ali62 to make a set!

[easixpedro]

Ouch! That stinks...fixable with some metal tubing  and wire inserts?  When I looked at your earlier pics, I was thinking that'd be my mod/fix before even attaching 'em. 

 

Watching your progress makes me really hope they do a whole family of Hueys--boggles the mind that such an iconic platform isn't currently kitted. 

-Peter

[Out2gtcha]

Thanks Peter. I personally cant WAIT for their Tarhe!   That is pretty much what I have in mind for the skid fix with a bit of a divergence in adding some tubing in the fuselage

[LSP_Kevin]

That's a bummer, Brian! Hopefully you can pin it back in place with some brass wire or similar.

 

Kev

[Out2gtcha]

3 minutes ago, LSP_Kevin said:

That's a bummer, Brian! Hopefully you can pin it back in place with some brass wire or similar.

 

Yep, Ill be adding some brass tubing into the fuselage, then will add some hardened piano wire to a cut groove in the landing skids. Similar to what Eric did on his O-2A only using wire instead of brass.

[Ali62]

4 hours ago, Out2gtcha said:

Thanks!

I'm hoping my idea works, otherwise I might be waiting for @Ali62 to make a set!

Hi Brian

 

i can make a set but it would take a while to get it all turned around, can you wait? I will also need to get some parts, skid parts, I do not really intend to buy a kit. Perhaps I can find someone in the U.K. that could loan me the parts.

what is the length of the skid out of interest, so I can get an idea for getting the guys to cast it.

cheers Ali

[Out2gtcha]

4 minutes ago, Ali62 said:

Hi Brian

 

i can make a set but it would take a while to get it all turned around, can you wait? I will also need to get some parts, skid parts, I do not really intend to buy a kit. Perhaps I can find someone in the U.K. that could loan me the parts.

what is the length of the skid out of interest, so I can get an idea for getting the guys to cast it.

cheers Ali

 

Thanks Ali!

I will go ahead and implement a fix for this one, but I definitely plan on making more Cobras, and I think that brass skids for this kit will be needed by anyone building need it.

[petrov27]

wow crap that sucks - I just glued mine in over the weekend now I wish I had drilled em for wire or something.

[Uncarina]

Bummer Brian, but I know for you this isn’t a deal breaker by any means.

 

Cheers,  Tom

[Out2gtcha]

Thanks gents. Solution is in effect! Pics tomorrow as I need some sleep before work tomorrow.

The wife is out of town with her mom and sister, so it's model on fully tomorrow. 

I think the solution I have come up with not only adds the needed stiffness/strength, but also accomodations the scale rod base of each skid connection (the aerodynamic part of the late Cobra skids are not directly in contact with the fusalage).

[Out2gtcha]

As promised, pics of the start of the fix for the skids.

The first step was to clean up the area around where the OOB skid nubs broke off inside the fuselage. Fortunately in this case I used some Tamiya fast evap  extra thin cement and the pegs where fully welded in and were easy to sand flat and re-scribe. I still have yet to do any finish sanding or cleanup here:

 

 

 

 

 

 

Next up was a start to fixing the skid kids themselves. First off I smoothed out the ends where the nubs broke off, and center punched (delicately) where the previous nubs had been. Then after a quick pass or two with the sanding stick, I used consecutive sized mini drill bits to bore holes from the center of where the nubs used to be right through and out of the front top of the skids.

This was NOT pretty, but I had a plan.........

Past experiments with hardened steel piano wire are two fold:

One, it is very strong and the perfect rigidity for this kind of fix. Two, while piano wire is workable it still is metal wire and in the case of the Cobra, this meant slightly thicker steel rod, and that meant it was going to be tough to cut. That being said, the OOB landing skids are thin plastic prone to warping out of shape without super heating any thick wire. Wire that thick is hard to cut and creates a lot of heat, so piano wire was out for my plan.

I grabbed some suitably thick carbon fiber rods I had on hand from some R/C parts I had and cut them into 4 workable 1"/25mm pieces. I then saturated those in very thin CA.

After the CA was dry, I imbedded them in the skids making sure to keep them at the right angle horizontally, as well as lining them up perpendicular to the fuse.

Once the carbon fiber rods were tac glued in place with thin CA, I came back later and filled in all the surrounding area with very thick CA.

Again it was not pretty at this early stage, but knowing it was super strong and flexible carbon fiber in there instead of steel, I knew it was going to be way easier to work once everything had a chance to harden off.:

 

 

 

 

 

The next part of my plan involved some appropriately sized stainless steel tubing. I drilled the correct holes exactly over the top of where the OOB nubs were, cleaned up the holes and made sure the tubing fit.

You can kinda-sorta see where I'm taking this:

 

 

 

 

 

 

Once glued in they will sit something like this, a bit proud of the surface. Probably even slightly less than this, but this is just an estimate. In the end they will ever so slightly embed inside the skid base to make a much more stable and stout base for the skids:

 

 

 

 

 

As I had hoped, the carbon fiber rods remained very strong and light of course, but unlike the same sized steel rod, I also found them to be extremely easy to work. They sanded perfectly and I used my Dremel to make short work of the carbon/CA mix and got the skid mains roughly but delicately smoothed out.

After the Dremel work I used some sanding sticks to take it down until it was just a bit more smooth, but still rough enough to have a bit of bite for the forthcoming step.

I then mixed up some JB Weld, and slathered that all around the top and bottom of the main part of the skids. The carbon fiber rods remained sandwiched in mix, and since they were sanded down a bit, all I have to do is sand down the JB Weld a bit and should be GTG. The JBW was smoothed out prior to setting with some Mr Color thinner to make the eventual sanding stage easier:

 

 

This all hopefully will lead to a much more stable and strong landing gear set up. I still do believe the best solution to this would be to have Ali work his magic on these and make a set of sturdy and strong brass landing skids for the Cobra.

The JB Weld should be cured well be later today, so should be good to sand them smooth in prep for some primer and possibly some filler.

 

Cheers and thanks for looking in on me

 

 

[easixpedro]

Nice recovery! Well thought out and executed--and thanks for sharing so everyone can avoid the impending disaster, as I have a feeling it's not a case of if, but rather when.

-Peter

[Out2gtcha]

Thanks! I keep forgetting how close you are Peter. I completely agree after only dealing with the OOB skid connections for about 20 min (the amount of time they lasted before I broke them off). I think that unless you are super delicate at all times, wait to put the skids on until the VERY last, or are just much less ham-fisted than I am, these will brake for most people.

Kind of like the main float X-braces on the KHM OS2U; not a matter of if at all. 

[petrov27]

Yep nice recovery there!

 

If anyone does produce brass replacement I hope they consider doing the tailskid also; I realize a piece of wire would do in a pinch to replace, but it has a taper to it that wire would not quite get.