Next in line Madcow Jayhawk

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AfterBurners

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This came in the mail today. I tried the retainer on. What do you guys think? Slimline?? Maybe something else??

Definitely upgrading the shock cord and probably chute?? I have a military flare chute that will set this down very gently.

Of course this will be an all wood glue build. Pretty boring right? Gotta love Titebond II.

Back to the Slimline retainer. I think they only fit Giant Leap tubes? Not 100% positive on this. I called them yesterday just waiting to hear back.
 
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Nice looking kit ! The engine sizes look a little tame for you --gonna up-engine?
 
Nice looking kit ! The engine sizes look a little tame for you --gonna up-engine?

Its a 29mm might consider an H97 in this kit. We'll see. I need to get the CG and CP right on this. This should be the only challenge on this kit and maybe getting the holes drilled accurately in the nose cone. My friend has a drill press so I have that covered. I also forgot to order a bulk plate since I need to add plenty of ballast to the nose.
 
The slim line retainer will fit the paper tube loose. Not a problem though. Just build the end of the tube up with a wrap of glass or shim evenly around and use extra JB weld. The slim line retainers even loose on some glass tubes. Personally I would carefully enlarge the end of the balsa tail cone so you could recess the slim line. Also harden that tail cone with CA or glass it.
 
The slim line retainer will fit the paper tube loose. Not a problem though. Just build the end of the tube up with a wrap of glass or shim evenly around and use extra JB weld. The slim line retainers even loose on some glass tubes. Personally I would carefully enlarge the end of the balsa tail cone so you could recess the slim line. Also harden that tail cone with CA or glass it.

Great suggestions! Thanks! :)
 
Tapered tailcone! :grin:

I think I saw one posted somewhere (Jayhawk thread?) and it looked really awesome!

Regarding Slimline, I just put one on yesterday and followed the instructions where it said that if the fit is a bit loose, "attach three small strips of tape to the end of the motor tube, 120 degrees apart, to tighten the fit", then use high temp epoxy. Worked like a charm. I've used masking tape wraps prior to this, but this method sounds a lot better to me. I think I have the same kit, so if I have time, I'll see if I can dig it up and check the fit on the other slimline 29mm retainer I have.

BTW - Last I checked, Hawk Mountain was out of the 29mm Slimline. I got mine from Giant Leap.
 
Tapered tailcone! :grin:

I think I saw one posted somewhere (Jayhawk thread?) and it looked really awesome!

Regarding Slimline, I just put one on yesterday and followed the instructions where it said that if the fit is a bit loose, "attach three small strips of tape to the end of the motor tube, 120 degrees apart, to tighten the fit", then use high temp epoxy. Worked like a charm. I've used masking tape wraps prior to this, but this method sounds a lot better to me. I think I have the same kit, so if I have time, I'll see if I can dig it up and check the fit on the other slimline 29mm retainer I have.

BTW - Last I checked, Hawk Mountain was out of the 29mm Slimline. I got mine from Giant Leap.

That would be great.. let me know what the fit is like. Worse cade I can use the AP
 
I'd open up the tail cone and recess the whole retainer. Drill two holes in the cap of the retainer and use a spanner to tighten it.
 
Tapered tailcone! :grin:

I just realized I may have been thinking of some other Jayhawk with a straight bt since this one already has a tapered tailcone. :facepalm:

I'd open up the tail cone and recess the whole retainer. Drill two holes in the cap of the retainer and use a spanner to tighten it.

+1 I had actually suggested the same on a "Wildman Jayhawk Motor Retention" thread last year where I said I saw a Madcow build with it recessed and it looked great. :)
 
I dug up the MC JH I had and checked the Slimline fit on the mt and it is looser than the one I just installed on my build; however it still seems doable. Here's pics of it centered as well as pushed to one side.

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It still might be the best solution if you want it recessed though since it is the slimmest retainer I know of (barring tape) and you should be able to have it flush and still use the retaining clip. A screw on retainer would be a bit trickier to get in there without making it to more difficult use.
 
I dug up the MC JH I had and checked the Slimline fit on the mt and it is looser than the one I just installed on my build; however it still seems doable. Here's pics of it centered as well as pushed to one side.

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It still might be the best solution if you want it recessed though since it is the slimmest retainer I know of (barring tape) and you should be able to have it flush and still use the retaining clip. A screw on retainer would be a bit trickier to get in there without making it to more difficult use.

I'll kick the idea around. It seems if modify one you have to modify everything else. I might design my own or leave it off altogether? Not sure yet?? I have a Madcow retainer but not sure how well it would hold up mounted to balsa?
 
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Let it set over night with one coat of CA and spent 5 minutes this morning sanding with 220 and then 320. It's so smooth right now it feels like it will slip out of your hands when you handle it. I'm going to go over it with sanding sealer and follow it with balsa filler primer. I used CA on some balsa nose cones and always liked the results.
 
I decided just to go with tape retention. I'm not gonna flew too many H motors on this do I think I'll be alright. I have some MC retainers but not sure if mounting the set screws into balsa is a good idea??? If I drill in its possible that once I screw them in they can crack the sidewall of the tail cone. After you get the tail cone in place and the front ring there's not much of the motor exposed out the aft end of the tail cone. I'll have to check but probably a 1/4"
 
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I decided just to go with tape retention. I'm gonna flew too many H motors on this do I think I'll be alright. I have some MC retainers but not sure if mounting the set screws into balsa is a good idea??? If I drill in its possible that once I screw them in they can crack the sidewall of the tail cone

That will give max performance since it will require less additional nose weight, especially if you are using big motors. I used tape too but if you are a stickler for looks it might not be the best. I have flown mine a lot on AT 29 mm G's, mostly G 64s and the Mohave Green 78's. The short delay ones can give a small zipper so medium delay is best. Really focus on the long wing root joint and fillet. That is were it will crack over time or on a hard surface landing. The paper will give way, not the glue. Love the Rustolem engine orange if you can still find it.
 
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As I mentioned before going stay with tape method. I should be fine. I doubt I'll fly anything bigger than a G64. The instructions call for attaching the shock cord around the motor tube. I opted our and decided to use an eye screw. Didn't want to chance of the fin tabs coming into contact. I used epoxy on the eye screw and will anchor it with epoxy clay. It's not going to go anywhere. I also tossed the old shock cord and upgraded to a one 12 foot piece. Extra is always good.
 
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I've always used slip knots with a lot of success. No glue necessary. They cinch down nicely. Finished off with heat shrink. Eye screw secured with epoxy clay. Dries like concrete.
 
Despite the many times I've defended the use of friction fit, I have to admit that I don't trust myself to risk reloadable hardware. I'm sure you will be fine. I'd use an Estes PVC retainer if I built it again.

Your attachment method looks great.
 
Despite the many times I've defended the use of friction fit, I have to admit that I don't trust myself to risk reloadable hardware. I'm sure you will be fine. I'd use an Estes PVC retainer if I built it again.

Your attachment method looks great.

You're right I was kicking around a lot but wanted to keep the lines clean on this and I didn't want hassle with modification of the tail cone to fit the slim line. I felt the MC plate retainer would have been nice but a likely chance it could split the cone. I figure 3-4 wraps of tape and I should be fine. I'm considering a 36" flare chute on this. Should bring it down nicely. I placed an order with hobbylinc for some epoxy then I'll install the mmt. Just using on the front ring not tail cone. Wood glue there. Easy to wipe and sand.
 
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I haven't posted anything for awhile, but wanted to say the bottom portion is ready for paint. I still need to work on the nose and drill the holes to mount the canard fins.

A couple things. Just wanted to thank Mike at MADCOW for the exceptional kits that he sells and his outstanding customer service. Before I glued up the main wings I noticed that one was badly warped, so much that it looked like a wave. :lol: I was going to contact Mike, but I knew I would be building another one of these kits so I didn't bother. That's the way I am. If I like a kit I'll build 2-3 times and really perfect the build process. This one however is my first go round and through it all I found out a better way to build it, mostly in the finishing of the wood parts.

I did however contact Mike afterwards and he mentioned he would have gladly replaced it, but for me it was no biggie. The quality of the wood and the grain was poor, but I worked with it. Here's the thing that I found out. When you build this kit assemble the main wings first to the airframe and do all your wood filling and prep work. The way the grain runs it just makes more sense to do it that way when sanding the direction of the grain. Also do the same for winglets and attach them after they have been prepped. I find by doing it this way the grain is less likely to come through.

Some areas of the wing I was unable to hide all the grain, but on the next build I'll be able to do a better job finishing it. I also feel that the quality of the wood if better would have provided better results. Over all this is a fantastic kit and I would recommend to anyone who wants a quality kit for a reasonable price

Anyway are some attached pictures of the build prior to paint. I plan on painting it Chevy Orange with a basecoat of white to pop the color.

Any suggestions are appreciated.

BTW I apologize for the sideway pictures. They are normal on my PC not sure why when I upload they come up looking like the way they do??
 
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Yesterday I went ahead and painted the Jayhawk Chevy Orange. I love the color, but noticed a lot of areas where the paint went on dry or over spray was pretty noticeable. It seems for me anyways I can't escape it. I can get one section to look great, but in the process of doing so I get the other side with over spray. It's a vicious cycle:facepalm: To make it worse the engines enamels from Duplicolor spray in a "cone" shape pattern, not a fan, which can be adjusted.

So I went ahead and wet sanded the finish and got it pretty smooth, although as always because I only had maybe a couple coats of paint on it I sanded through on some areas. Normally what I do is after I apply say 3-5 coats of paint I wait about 30 minutes and apply several light coats of clear, which really makes it look nice. Then after it dries I come back and wet sand and polish the finish, but a lot of time I just leave "as is" and it looks great.

I'm going to come back and laid down a few more coats of Chevy Orange and then the clear like I always do. I think the reason why I didn't this time is because I did a lousy job painting the orange as far as over spray and dry spots, that I felt the cleat clear wouldn't help as much. Pictures below are of the Jayhawk after I wet sanded it. You can see the areas that I sanded through

A couple things I learned while building this kit. Next time I decide on building I'll attach the main wings already sanded and primer and then attach the winglets, because if you do it this way it's a lot easier to sand the main wings in the proper direction of the wood grain. When you have the winglets on it makes it very difficult.

I also learned not to wet sand the primer coats, because doing so causes the wood to delaminate or swell showing the grooves in the grain. I did in fact go back and sand the wood down and filled in all the imperfections.

I apologize for the side ways pictures etc. I've been trying to post these pictures right side up as they are saved on my computer and I can't seem to do it. WTF!!!? It pisses me off that this site as changed so much that you can't properly upload pictures!!!

I can't even delete the ones I have and try to reload. Now they are in some kind of gray box???

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I'd open up the tail cone and recess the whole retainer. Drill two holes in the cap of the retainer and use a spanner to tighten it.

I was going to suggest this too .. balsa is easy to ream out the hole to recess the retainer .. and the ol CJ trick of drilling a hole (or two) in the cap to use a finishing nail to loosen .

In my opinion the cap does not have to be flush with TC or completely recessed ..spacing it so when the cap is off the retainer body is flush .. when the cap is on it will stick out a bit and if loosened with a nail it can be fingered the rest of the way off or on . .. but if off looks clean

Kenny
 
I'm done with the clear coat and yes I have some dry spot and over spray, but debating whether or not to wet sand it polish it out. I wasn't planning on it on;y because I know I'll probably crash and burn and I had planned on building this kit again after learning from the first time how to improve the build process. I have a week to think about it I guess? Letting the paint dry for now.


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If it was mine I wouldn't wet sand it. I would make sure I had enough gloss to make the decals set down and adhere properly, then I would use a flat clear coat over the whole thing. The flat clear protects the decals, covers a multitude of finishing sins and is appropriate for a military bird. I also happen to like flat finishes on anything that looks scale.

If I was going for gloss I would sand out anything that was a bad drip or run, or anything that really came out rough. I wouldn't really wet sand and polish until the final coat over any decals.

My :2: of course...

That thing is looking great, by the way!
 
If it was mine I wouldn't wet sand it. I would make sure I had enough gloss to make the decals set down and adhere properly, then I would use a flat clear coat over the whole thing. The flat clear protects the decals, covers a multitude of finishing sins and is appropriate for a military bird. I also happen to like flat finishes on anything that looks scale.

If I was going for gloss I would sand out anything that was a bad drip or run, or anything that really came out rough. I wouldn't really wet sand and polish until the final coat over any decals.

My :2: of course...

That thing is looking great, by the way!

I already shot clear on it...maybe the next one I build I'll use a flat clear on it. I should have painted it flat orange, but not even sure if it exist?
 
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