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Building a Javron Cub

drl,
don't sweat it,a lot on here don't have a clue whats being discussed either!!!!

jr.;-)
 
Tape anything the fabric touches. ........and anything the fabric "might" touch also!

Piper didn't, and CC doesn't......for reasons of production ease I am certain.....but.........

.



Production like Piper and CC lend to shortcuts that work okay for the masses.

But if you're building an a/c that you want to stay nice for a long time.....you finish tape on the outside of the fabric any thing that touches the backside or comes close to it....think fabric drumming, ground handling, wing covers, gust locks. YOu need to give a fabric doily or doubler anywhere WEAR can get at your cover job!!!
 
Cup Holder!!

Josh Peppard has those cool slide-out cup holders in his Producer (stretch Pacer HOTROD!) They are cool.

I"ve use a closeable cup, but I've found it laying under the rudder pedals more than once...not good.

Spitoon????? May as well place to collect urine, too. BOTH are VILE!!! I am soooooo glad to not have a compulsion to chew tobacco. My compulsion to urinate is bad enough with all the coffee:)
 
drl,
don't sweat it,a lot on here don't have a clue either!!!!

jr.;-)

true, even as adjusted:lol:

loose things rolling around on the floor are often lodged between controls and an immovable object at critical times:-?

corral your thermos and round drink bottles...
 
Man, how did we get to bodily fluids? You guys are sick I tell you. Sick, Sick, Sick........ "You're a sick little man" :lol:

P1000979.jpg


When you make this panel don't forget to put the fuel selector panel on (with the associated nutplates). I forgot on the last build and you can go back and do it but it is a bit of a pain. Better to do it before you put the fabric on..........just a reminder.

P1000980.jpg


Since I am doing a fabric headliner Vs a metal one, I have to do something about this. The end of the throttle cover is right next to the back seaters elbow. Not only is it unattractive but it would be unsafe to have that edge there.

P1000982.jpg


This is the start. It will get rounded, trimmed, cleaned up, etc. and ..... (oh yea....nutplates). It will get riveted on, then a little JB weld here and there, and when painted it will look like all one piece, hopefully.

Just ideas and as always........... "hope it helps"

Bill
 
Bill, just a thought, And your doing it the way you like. But the panels where your feet are there on the side, wouldnt only about 1/2 way up be ok? Alot of those 2 panels cant be seen? I was just thinking high enough for dirt on top of the shoes.
 
Thank you fabricfan

Sheetmetal Cutting tip.

If you have access to a Sheet metal shear, like the one mentioned above (earlier in this thread) here is a tip that is pretty cool. You should probably have a set of snips....left, right and straight cut. If you do not have these yet I recommend you get a set as you will use them often. If you will look at the left and right snips you will see that one side of the jaws move and the other jaw is stationary. When you make a snip in a piece of aluminum the moving jaw will actually bend the metal down. If you were to make a cut with both the left and right you would see that they bend the metal down, one on the left and one on the right. Whichever jaw moves, the metal will be bent down on that side. It might look something like this.......

P1010011.jpg


And the little bend will look like this.......

P1010012.jpg

It helps if you move the snip handle down slightly as you make the snip. It just makes the bend a little more pronounced.

If you need to make a straight cut all the way across a piece of sheet, put a little snip in each end of your cut line, one with the left snip and one with the right. You will then be able to pull these little dog ears up against the back edge of the shear and get a perfectly aligned cut right on your line.

This is what it looks like pulled up against the shear......

P10100131.jpg


This is easy to show and a little harder to explain, so maybe ask the person whose shear you are borrowing to show you this trick.

Cargo Bay Side Panels

Once again we are wrestling with the cargo bay. When the floorboards rest on the lower longerons Vs having the usual shelf with the cables running under the floorboards, it creates a few problems. Namely how to protect the rudder cables from your cargo. You don't want you tent resting on a primary flight control cable. I tried making the side panels out of a carbon fiber honeycomb sheet panel but that left me with exposed rudder cables. My options were to fiberglass in some type of soffit, put a tube in and run the cable in that tube, angle the sides in enough to put the cable behind the sides, etc. I fussed with several options and just did not like the way things were working out. Note in this photo that the cable guide is held out away from the side tube about an inch. This is the guide just behind the rear seat....(this is not the problem)

P1010014.jpg


This is the cable guide at the rear of the cargo bay.... note that is is flush against the tube.......(this is the problem).....

P1010015.jpg



This makes it really tough because anything you put on the sides, the cable will rub against it as there is insufficient clearance for the rear cable guide. I tried running a carbon fiber tube to encase the rudder cable.....it would have looked like this.....

P10100202.jpg


But, again, it had clearance issues and further I was not happy with the appearance. Light, yes. Ugly, yes. Expensive, yes.

So.........I resorted to the old standby. .016 sheet with a bend in it to shield the cable and then fabric covered. Looks like this.......interior side....

P10100172.jpg


Back (or out) side........

P10100182.jpg


There are three tabs on the lower longeron on each side that hold the floor down. I used those tabs to attach a bracket for the bottom of the side panel. This uses that tabs and screws already in place to keep it simple and light. The tabs look like this.....

P10100212.jpg

(note the cut to the floor panel required to get it in and out)


The finished product looks like this.........

P10100243.jpg


What is the price?

The carbon fiber side panel and carbon fiber tube weighed 24.9 oz
The .016 aluminum covered with fabric weighed 29.5 oz

So the weight penalty will be 4.5 oz per side (and I will fabric the back panel as well just for looks) for a total added weight of about 13 or 14 oz. Not too bad. Much cheaper than all the carbon and also much easier and quicker to do. I have fussed with this and wasted a lot of time trying to figure out how to solve this problem. Hopefully others that are considering putting the floorboards on the longerons will be able to use this to save time, head scratching, money, and effort. Sometimes things don't work out quite the way you had envisioned. Its all part of building a CUSTOM aircraft.
Sorry it has been a while since I have posted. I have been a little busy at work. Hopefully I will be able to get back on track and get this Cub built.

Hope this helps

Bill
 
Great looking job Bill can't wait to have you bring it out here and get it dirty. Migrating season here goose poop all over everything.
 
for nice cut edges,

take a prep cut 1/8"- 1/4" away from finished cut(or 2 or 3 cuts..) you want, in the scrap, then take the final cut, -making sure the finished cut piece has the cutter jaw laying flat and curling the scrap piece, which will put all the curl/distortion in the thin scarp cut, not the finished part...
 
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Another tip

You can dimple a nutplate. You can also buy them already dimpled but they cost a lot more. They may be marginally better but this will certainly work

P10100321.jpg



Ends up looking like this..............


P10100332.jpg



The floor boards are held on with screws (or AN3 bolts) and fender washers like this......

P10100361.jpg


I needed a way to keep the side panel from being pushed outboard. So I made a bracket to replace the fender washer with that also has a nutplate for the side panel. Like this..............

P10100342.jpg


From the inside.............

P1010037.jpg


And from the outside..............

P1010035.jpg





On the left rear cargo panel I needed just a little more clearance for the flap cable where it comes down into the pulley next to the floor at the bottom of the reversed dogleg brace. It looked like the cable might rub against the side panel.
So...........that little trick we used to make the tight bend in the boot cowl can be used in a slightly different way here.......
Find something with a slot in it, or create one using wood. I found this slot from part of my foot shear......

P10100262.jpg


Now find some tubing that will fit loosely in the slot. This just happens to be bushing material so it is pretty thick walled....

P1010027.jpg


Now take a plastic mallet and tap (OK, tap pretty hard) it down into the slot...........

P10100281.jpg

It will look something like this...........(test piece)....

P1010029.jpg


And the finished product will have a nice channel in it giving you a little slot for the cable to run in with out rubbing on the side panel................

P10100301.jpg

It is not this tight in real life. Photo makes it look like it is still rubbing, but in reality it worked out great.

A couple of thoughts. I am using .016. This would be a lot harder as the thickness of the material goes up.

I'll post some weights for the interior panels in the next couple of days. I left that data at home.

I was fortunate to have my friend Jim come over and help out this week. He does great work and he pushes me. I can get lazy sometimes. Thanks Jim.

Hope this helps folks

Bill
 

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Thanks Bill !!! I've got a few of those exact forming "dies" around here! lol
 
Thank you fabricfan

Sheetmetal Cutting tip.

If you have access to a Sheet metal shear, like the one mentioned above (earlier in this thread) here is a tip that is pretty cool. You should probably have a set of snips....left, right and straight cut. If you do not have these yet I recommend you get a set as you will use them often. If you will look at the left and right snips you will see that one side of the jaws move and the other jaw is stationary. When you make a snip in a piece of aluminum the moving jaw will actually bend the metal down. If you were to make a cut with both the left and right you would see that they bend the metal down, one on the left and one on the right. Whichever jaw moves, the metal will be bent down on that side. It might look something like this.......

P1010011.jpg


And the little bend will look like this.......

P1010012.jpg

It helps if you move the snip handle down slightly as you make the snip. It just makes the bend a little more pronounced.

If you need to make a straight cut all the way across a piece of sheet, put a little snip in each end of your cut line, one with the left snip and one with the right. You will then be able to pull these little dog ears up against the back edge of the shear and get a perfectly aligned cut right on your line.

This is what it looks like pulled up against the shear......

P10100131.jpg


This is easy to show and a little harder to explain, so maybe ask the person whose shear you are borrowing to show you this trick.

Cargo Bay Side Panels

Once again we are wrestling with the cargo bay. When the floorboards rest on the lower longerons Vs having the usual shelf with the cables running under the floorboards, it creates a few problems. Namely how to protect the rudder cables from your cargo. You don't want you tent resting on a primary flight control cable. I tried making the side panels out of a carbon fiber honeycomb sheet panel but that left me with exposed rudder cables. My options were to fiberglass in some type of soffit, put a tube in and run the cable in that tube, angle the sides in enough to put the cable behind the sides, etc. I fussed with several options and just did not like the way things were working out. Note in this photo that the cable guide is held out away from the side tube about an inch. This is the guide just behind the rear seat....(this is not the problem)

P1010014.jpg


This is the cable guide at the rear of the cargo bay.... note that is is flush against the tube.......(this is the problem).....

P1010015.jpg



This makes it really tough because anything you put on the sides, the cable will rub against it as there is insufficient clearance for the rear cable guide. I tried running a carbon fiber tube to encase the rudder cable.....it would have looked like this.....

P10100202.jpg


But, again, it had clearance issues and further I was not happy with the appearance. Light, yes. Ugly, yes. Expensive, yes.

So.........I resorted to the old standby. .016 sheet with a bend in it to shield the cable and then fabric covered. Looks like this.......interior side....

P10100172.jpg


Back (or out) side........

P10100182.jpg


There are three tabs on the lower longeron on each side that hold the floor down. I used those tabs to attach a bracket for the bottom of the side panel. This uses that tabs and screws already in place to keep it simple and light. The tabs look like this.....

P10100212.jpg

(note the cut to the floor panel required to get it in and out)


The finished product looks like this.........

P10100243.jpg


What is the price?

The carbon fiber side panel and carbon fiber tube weighed 24.9 oz
The .016 aluminum covered with fabric weighed 29.5 oz

So the weight penalty will be 4.5 oz per side (and I will fabric the back panel as well just for looks) for a total added weight of about 13 or 14 oz. Not too bad. Much cheaper than all the carbon and also much easier and quicker to do. I have fussed with this and wasted a lot of time trying to figure out how to solve this problem. Hopefully others that are considering putting the floorboards on the longerons will be able to use this to save time, head scratching, money, and effort. Sometimes things don't work out quite the way you had envisioned. Its all part of building a CUSTOM aircraft.
Sorry it has been a while since I have posted. I have been a little busy at work. Hopefully I will be able to get back on track and get this Cub built.

Hope this helps

Bill

Bill you should write this up (the shear tip) in Mike's tool's, jigs, fixtures thread. I can't tell you how many times I think about you while using my shear . I struggled with bad eyes for so long making cuts that seemed impossible to make come out close. Now with your method they all come out within a couple thou and take way less time! There is another advantage: Since you have already started the cut, the shear will remove tiny (like 1/8 inch) pieces without "foldover" where the scrap folds instead of being cut, jamming between the knife and the bed, common using Chinese shear for very small cuts. I didn't use to try cutting anything less than 1/4 inch.
 
Since you have already started the cut, the shear will remove tiny (like 1/8 inch) pieces without "foldover" where the scrap folds instead of being cut, jamming between the knife and the bed, common using Chinese shear for very small cuts. I didn't use to try cutting anything less than 1/4 inch.

gsmx440, you need to adjust the blade on your sheer. Not sure of your exact model, however there should be some adjustment screws to change the gap between the blades. Close up the gap until you can place two pieces of paper on the sheer and it will only cut the top sheet. It is a fussy adjustment that only needs to be done once. If your machine folds over both pieces of paper, then your gap is too wide. You want it to cut the top sheet and fold the bottom sheet of paper.
 
Jim and I took a road trip this week and visited Larry Dawley of WWW.Dawleyaviation.com. Larry and Jim are friends and I am fortunate to piggyback on that. I had a chance to pick his brain a little on exhaust systems and also the possibility of a custom experimental system. He is doing some research for me now.
But, on a side note, this guy does awesome exhaust rebuilds, and new builds, and would certainly be someone I would recommend for all your exhaust needs.

Next-we spent a day in the hangar doing little stuff but one thing I would like to share would be the cargo net tie-down rings. I had Jay at Javron weld in a couple of attach tabs so I could have a cargo net in this cub.
These tabs weighed 1.0 and 1.2 ounces respectively. The ring base with all mounting nutplates, screws, etc. weighs 1.1 oz so the total weight added for this feature is 6.5 ounces (including the hook attach rings in the birdcage as shown on about page 5 of this thread).
Obviously the cargo net and the attachment hardware will add weight but that will only be in the plane when needed. So for the cargo net option, the weight I will carry at all times is about 6.5 ounces. I felt the safety benefit was worth it.

Here is a picture of one of the tabs, from underneath the floor, with the nutplates. The nutplates allow the removal of the floorboard without having to cut an access hole in the fabric.......
P1010039.jpg


Picture of the base.....

P10100421.jpg


Another picture of the ring base....

P10100411.jpg


And a picture of the base with the attach ring installed.....

P10100402.jpg


I got these from Vans
http://www.vansaircraft.com/cgi-bin...034503-408-6&browse=airframe&product=tie-down

They claim they weigh 1.5 oz but I did not use the large washer and I was able to shorten the screws thus the weight came in at 1.1 oz. each.

Wing update - Jay is really pushing hard on getting his shop expansion done and that should help him get caught up on his backlog. It should be ready to move into next week. Jay felt like his new ribs flexed a little too much along the top and bottom so that rib stitching would twist the channel over a little and perhaps not look good and also maybe diminish its strength a little. It would be fine for riveting but a tight rib stitch could twist it. Sooooo........he is remaking the rib dies to add in a couple more vertical members. My guess is this will add about 1/2 ounce per rib. They will still be the lightest on the market, except for CC's, (but as of now CC will not sell you just a set of ribs,) thus they will be the lightest "available" rib.
He will be using a version of the Stewart wingtip, standard length aileron moved out to the wing tip, and thus a longer flap. My guess is about a month until the first wings are shipped.

Hope this helps

Bill
 
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Bill....Jim Richmond told me they would sell just a rib set I was told the same from sales unless that has changed recently...if so does that mean I have the only set that's not in a carbon cub.

DW
 
I also own a set of CC Ribs. Bought them last year after talking to Jim at the Anchorage show. Building up the wings as we speak. Do not own Carbon Cub.
 
I was under the impression they were not available but perhaps I am wrong. I guess a call to CC would be in order. Sorry if I posted bad info.

Bill
 
When I got mine they sold a rib kit with all the ribs for the carbon cub....so some you won't need and you may need to order some others...so take some time and do your research and know how your going to build your wing, when I bought mine they bought back what I didn't use at 50%.

DW
 
Folks

I don't always respond to all of the inputs I get on this thread but I do appreciate your interest, support, encouragement, help, inputs etc. So, if I have not said it lately......

Thank You

Now back to your regularly scheduled programing...........

Here is the way I take care of the hole in the saddle. If you don't fill the hole in the saddle that connects the vertical Stab to the top stringer you will have a really unsightly sag in the fabric here.
I make a saddle just slightly larger than the hole maybe 1/4 inch all the way around and I also make one about the size of the hole. I make these out of .016 Al. It is easy enough to bend that you can just use your fingers to shove it inside the fitting and it will bend pretty close to what you need. A little more finagling and you are there. Do the same for the other one and you will have something that looks like this.....
IMG_05841.jpg


I then epoxy the larger one in the saddle and the smaller one on top of that. You will end up with something that looks a little like this..........

IMG_05911.jpg


A little JB weld (or epoxy with micro balloons, or bondo) and a little sanding and you will have a nice smooth transition. Later, if you need to, a good sharp rap with a punch and it will all come out allowing you to remove the jackscrew. I'm sure there are other ways but this is just another idea for your bag of tricks.

Hint - I ordered a titanium firewall from Atlee Dodge and it is great. Saves two pounds. But mine came pre-drilled. I'm thinking you might ask if they can send you one that is not drilled.
When it came time to mount the gascolator, it was hitting the engine mount. Could be any, or all, of several factors. Not a factory gascolator (I like the Vans unit - light, cheap, well made), different engine mount (mine is lowered 2 inches and has the thrustline mod built in). Etc.
But the point is that the pre-drilled holes did not work. In this photo you can see the holes above the gascolator........

IMG_05791.jpg


Here you can see the holes in the firewall from the back side with the gascolator in place where it will fit. Not a big deal to put in new holes and enlarge the center fuel fitting hole but it could have been better.

IMG_05811.jpg


This is where it ended up........ about 1/2 inch lower......

IMG_0583.jpg


IMG_05821.jpg


So, if you buy a firewall, try to get it un-drilled.

This is an Odyssey Battery. It weighs 14p 2oz. The box weighs 15.2 oz I plan on using a lithium type battery but I will build my battery box to accomidate the UltraBat 13 from Ac Spruce (just in case the lithium problems are not sorted out by the time I am finished). The Ultra Bat 13 is a little smaller than the Odyssey and weighs 10.8 pounds.

IMG_0585.jpg


My good friend Jim has been really helping lately. It is amazing how much faster and better things go with a little help. Jim is very knowledgeable and we work well together. We brainstorm, debate, push each other, and usually, when the dust has settled, we come up with a better solution. After all......... "Building an airplane is just a series of problems to be solved" (from my neighbor - Glenn).
So Jim built a battery box for the Ultra Bat 13 battery. It weighs 5 oz. The savings from an Odyssey and the factory holder would be 4p 6oz. Pay attention, folks, to your weight. It would be easy to grab the Odyssey and holder, (they are good and well known products) but you would have added over 4 pounds. If that is what you want because you really like that product, and believe it to be better, thats great, I am not bad mouthing the Odyssey battery, just be aware that things are not all the same weight.

IMG_05861.jpg


I like to put my battery on the engine side of the firewall for a couple of reasons. Battery cables are heavy thus the shorter the run to the starter and alternator the less weight. Shorter wires also equal less current drop. When you preheat the engine it also preheats your battery and we all know cold batteries don't perform well. With the new light weight batteries you are really not going to see a big weight and balance issue. After all, you have cut 20 pounds off the front end with a light starter and alternator, and possibly 10 more with a Catto prop. So adding 11 pounds to the firewall after taking 30 away still leaves you lots of room.
The downside is the heat from the engine may shorten the life of the battery as they don't like too much heat either. I am OK with that. Actually I have not heard of any problems in that regard but just going with the logic that heat and electrics is generally not good combination I will throw that out there.

Another thing I did was have Jay build the Thrustline mod into the mount (saves a little over a pound) and I also lowered the front end 2 inches. I did this to get rid of the Thrustline kink. Preliminary test seem to show that this was correct amount of drop. This recreates the original smooth, slightly descending, line from the instrument panel to the Nosebowl.

IMG_05901.jpg


Exhaust

I am very Blessed to live near the right people. I had the opportunity to get a Sutton exhaust and to play with it a little.
I LOVE the simplicity of this unit. I have not had a chance to test it against a Vetterman or other system for performance (I am hoping for the chance to run both on a dyno. Unfortunately that is not cheap so I am working on it. If anyone wants to pitch in a little cash to test a couple of exhaust and carb air boxes just let me know. I don't mind taking a hit to help the SC.org community but right now that hit is a little more than I'm willing to take.)
I am working with Brian to take some weight out of the Sutton system. Current weight is right at 12 pounds (11p 15.6oz). It may be possible to get it down to under 9 depending on what we do. The Vetterman system weight depends on how you configure it. How many mufflers, heat shrouds, etc. Generally it seems to come in around 10 pounds at a minimum. So the muffler/exhaust system is still under review.....

Here are a couple of pictures of the Sutton system...

IMG_0587.jpg


IMG_05891.jpg


IMG_0588.jpg


Very clean, simple, and lots of heat.

Hope this helps and thanks again to Jim for all your help

Bill



 
Bill most autos have the battery under the hood, I would think that a black car sitting out in Vegas in July has tested the battery some. And every badass bike parks the battery right behind the hot cylinders.

Glenn
 
Bill, If you decide that there is too much heat on that battery, it would be fairly simple to make a light weight shroud out of .016" and a small blast tube connected to the top of the aft baffle. Of course you knew this. There is a lot of heat which emanates out of the side cowls from the 0-360 engine. My plane has no interior. I can feel a lot of heat with my hand on the inside of the fabric under the door when flying in cool temperatures. Actually I believe that it helps to heat the cabin. This leads me to believe that you will get a lot of heat directed to your battery. I'm not suggesting that this is good or bad. Just a heads up.
 
Thank you skywagon. It's an old Harbor Freight 30" model that set in my brothers barn rusting for years (It helped launch an empire actually). I don't know if it was ever correctly adjusted. The first 1/8" inch of the knife is broken off but I'll give your tip a try. I didn't know what the standard would be for setting the blade but I'll try the paper trick. One thing when you use cheap tools you learn to "compensate". As a matter of fact you spend 90% of your time and 10% more scrap "compensating".
gsmx440, I'm not familiar with that particular model. Mine is a different make. It has four sharp edges on both of the blades. You can remove and turn each of them to get a new sharp edge. Then make the adjustment which I have described and you will have a new sheer.
 
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