Mike, you are making regular headway so that is the important thing. You are still looking good and Ed's posts continue to have high educational value. this is one of the best building threads I have read!

Mike,

I am glad you're enjoying it. I have learned a lot myself.

I spent 8 hours yesterday getting the changes in to the CAD file. It is still my plan to build another B-36 using the updated documentation. The second build should go a lot quicker for a few reasons:

- I have the build thread on RC Universe to remind me how to build it
- The parts will all be on 1 or 2 sheets instead of approx 300 sheets which will save an incredible amount of plotting time
- Early in this thread I was told how to transfer the plot lines to balsa sheeting or plywood
- I have been contacted about creating sets (how many?) of laser cut parts which I will look in to when this B-36 is complete
- I won't have to install the landing gear 3 times
- The wing spars won't have to be moved
- The documentation will be up to date

I am sure that there will be more to add to that list after I get through the covering phase.

It was great to have the CAD software up and running again! It's complex software and I know how to use a very old version very well. I discovered that I had a CD with the appropriate version of Exceed 3D software which is required by the CAD software. I uninstalled the Exceed graphics software and then reinstalled it. That got me back up and running. What a relief.

I will get back to building tonight so that I can keep it moving.

Mike Roerig
[email protected]

I just finished editing the CAD file for the time being.

If you have a desire to see it, here's how.....

Download, then install this viewer: http://b36.flugmodel.net/Updating_he...06v1svlite.exe

Double click on 2006v1svlite.exe to install it.

Then download the updated CAD file here: http://b36.flugmodel.net/virtual_reality/Sept22.wrl

Run the viewer, Select File -> Open, then set "Files of type" to VRML 1.0 Files, select Sept22.wrl

Use your right mouse button to rotate the image, the middle mouse button or wheel to move or zoom. You can also try out the contrls on the right.

I just ran this and it worked fine. It's a cool way to view CAD files.

Mike Roerig
[email protected]

Wow, I can't believe how long it has been since I worked on the plane and posted here. I haven't been home much for the last 2 weeks. I will stick my neck out here and assume that there is still an interest. So here is an update.

I have the landing gear mounts in for the left wing.

In the 1st photo you can see that the old landing gear mounts have been removed. I have patched in the previous rib cuts and cut new gaps for mounting the landing gear. It also shows the gear set in to place. FYI, Ed pointed out that the gear should be rotated back by 5 degrees. To the best of my measuring I get 4 degrees for both landing gear. I don't want to cut the wing spar up by the retract mechanism to get enough room for 5 degrees. It shouldn't bee too tough to move the spar just a bit in the CAD file so that future builds will have 5 degrees.

The 2nd photo shows the retract mechanism and the mount blocks set in their approximate location.

The 3rd photo shows one mounting block installed as well as carbon fiber veil to strengthen this area. I can't believe how rigid the carbon fiber veil makes this area. You can also see that I added carbon fiber veil tie in the motor mount.

In the 4th photo I just wanted you to see that I cut through the wing skin. You can see the underside of the engine nacelle planking.

OK, this is a poor closeup photo again. I am trying to show in the 5th photo a small air gap between the wing skin and the engine nacelle. It's not a large gap but it will allow SOME air to in to the engine nacelle air intake, through this gap, over the motor, and out around the prop. So there won't be a large amount of air passing over the top side of the wing to cool the motor but when the bottom side of the nacelle is built I will get a lot of air for cooling.

The 6th photo shows the retract secured to the mounting blocks so that I can be sure it all fits before using CA and carbon fiber veil to secure the second mounting block.

The 7th photo shows the finished installation..... well, finished for now. I am going to add plywood strengthening later. I want to fit the flap and aileron Nyrod before adding the plywood.

I hope that a few readers took a moment to use the 3D viewer in my previous post to take a look at this plane in 3D.

I trashed my first attempt at this post with the backspace key. I will have uploaded the images twice now, so it will be interesting to see if it looks right when posted. If not, now you know why.


Mike Roerig
[email protected]

That is looking great! I did take a look at your CAD program, and it just made me want to get a CAD program even more!

Looks fabulous considering the minimum time you have had to concentrate on what you wanted to do for this.
I would create an isolated retract well to reduce the pressures which will accompany that large mains opening.
When you make your lower retact nacelle be sure to layer it with carbon fiber veil to stiffen it because it is so
large. You don't want it vibrating in the breeze.

Remember its how and not how much....you could use card board and it would have accomplished the same as
balsa after the veil and resin are laminated to it. Placing Syran Wrap flat onto a sheet of glass provides a good
platten for laying up veil, the properly sized card board strips, and another veil on the opposite side. Squeegy
and place second Syran Wrap on the top before laying another sheet of glass on top.

What you end up with is a light weight strip you can form into what you need on either side of the strut and the
wheel. If you have thin G-10 it works best because its ready made: ) Wanted to explain how to roll your own so
to speak.

Hi Mike

Just been following your build and it looks great

Cheers Bob T

JetFixr, I am glad to see that someone took a look. I really like virtual reality files because you can see in detail how the pieces fit together. I am sure that most people are hesitant to download an executable file for the viewer, but I'm glad you took the chance checked out the CAD design.

Ed, Thanks for the suggestion about cardboard, but I had planned to make the border around the landing gear using balsa soaked in water for a couple hours or more. It gets pliable when wet so I should be able to make smooth curves, just like you showed in your image. I thought that I should get the nyrod installed first. Thanks again for suggesting the carbon veil. That is incredible stuff! A small amount of carbon fiber veil and CA provides a lot of strength without much weight. Readers can go back a page or two to see the link directly to the product or they can go to home page for FiberGlast which is www.fiberglast.com I thought was priced right and it's shipped to you on a spool so there are not creases.

rt3232, thanks for the encouragement. Interest from readers helps keep me motivated. That hasn't been my problem recently though. I just haven't had the time. Sometimes I am on-call and I work evenings at home.

I do sneak in a few minutes here and there even when working from home. Using those minutes here and there I was able to get my plotter working tonight. A bought a used inkjet HP DesignJet 600 plotter that will make D size plots. I have been anxious to try plotting all of the fuse formers, ribs, and other sheet pieces on a single plot. I still need to rework the CAD file before I can make that plot, but tonight I got closer to doing it. If it works out, I will post the plot file so others can take it to Kinko's. I am not interested in plotting it for other builders though. They are costly plots even on my own plotter and I don't want to sell anything to anyone, not even for cost. You can have the design and plot files free of charge and take them to Kinko's.

Well, that's it for now.

Mike Roerig
[email protected]

How will you form the shape with the balsa after soaking it in water?

Don't feel bad about not having a lot of time of late, it just means you enjoy it all the more when you do get to work on the plane.

Mike

Ed and all,

Take a look at page 1 of this thread. The 2nd post from the bottom has a photo of my soaking jar for the strips that I used to plank the fuse nose. I will do something similar for making the border around the landing gear. After soaking, I will wrap the balsa around a jar or pop can to get a fairly even curve. The strip will be about 1.5 inches wide. I was shown this method by a local modeller and I have used it with success. The CA still works on wet balsa which surprised me. For a strip this wide, I might let the balsa dry against the curved surface before adhering it because I will have to sand the edges to match the curvature of the wing skin.

Mike

Mike,

Nice to see you back. I hope all is going well for you.

I'm not sure if I am apologizing, making excuses, or just explaining that I haven't had time lately. I do know that I need to stay enthused about this project so that I take it to completion.

Over the lunch hour I have been reading the Futaba 10C manual. It's interesting reading and has cleared up a lot of my misunderstandings about which transmitter, transmitter module, and receiver to purchase for a FASST system. The manual can be downloaded from the Futaba website if anyone has an interest.

That's it for now.

Mike Roerig
[email protected]

Be sure to allow at least .125 on all sides of the tire ans strut tube. That permits
your vibrating strut to settle down a bit before it rises into the retract well.

This weekend I had some time to work on framing in the retract area.

On Saturday I cut some 1.5" x 9" balsa strips using very light balsa and some harder balsa. I put them in a large water bottle and let them soad for about 24 hours. I tried bending the strips to the 2.5" diameter that I need for the wheel wells. The soft balsa strips bent much easier than the harder balsa strips. I tried a couple of each type strip but each time I kinked the balsa strip.

The balsa strips on the nose of the B-36 bent rather easily but these were more difficult. It may be the width of the nose strips is about .125" and these are 1.5". In an effort to made it work with the 1.5" strips I throught to drain the cold water from the container and fill it with hot water. I let the strips sit in hot water for about 10 minutes and then I tried bending them. They bent easier and to my surprise the harder balsa strips bent easier too. I got the very light balsa bent to about a 4" diameter without too much effort but I got a bit anxious and kinked them too. I didn't kink any of the harder balsa strips but I didn't get them down to a 4" diameter. It was a bit tricky taking balsa strips out of very hot water and get them bent before they cool. They cool very quickly.

At this point I ran out of non-kinked strips so I made some new ones yesterday and put them in water. I still think I can get a 4" semi-circle made from 1.5" wide strips. The next time I try this I am going to drain the cool water, add hot water, and then place it all in the microwave until it boils. I will keep the strips in the water for about an hour and reheat it to boiling when needed. I think this will make the balsa strips pliable enough to shape and keep their shape.

Hopefully the second attempt will be a winner.

Mike Roerig
[email protected]

Corrections to my previous email.... I put the strips in a water bottle to soak (not soad) for 24 hours.

Also, I need to bend them to a 2.5" diameter, not a 4" diameter.


Read before posting... Read before posting....

Mike Roerig
[email protected]

That's OK, we were all onboard your last post. Considering the tight diameter you were trying to coil those strips of balsa its a wonder you didn't come apart at the seams... Seriously, this thread is about to bust a seam and take off like a rocket. Looking forward to all the pending steps for your B-36

Mike, try adding a couple of ounces of ammonia to the water and see if that helps your bending radius. I remember this from my free flight days when I was a kid. I think it was an idea from Carl Goldberg. The ammonia makes the fiber more pliable.

If it doesn't work well for your purpose, oh well, nothing ventured, nothing gained.

Don

Ammonia might alter or interfere with the cure of the CA you planned to use to adhere the line
components in the cut outs. While ammonia will do the trick for relaxing cellulose fibers it just
might eliminate the bond of the CA as well. Then again you might be launched into a 60's era
trip of sorts...one from which you might not return...[sm=bananahead.gif]

Just a thought...

Well, I can try the ammonia and see if that helps. Heating the water made a noticeable improvement. A 2.5" diameter bend is quite small but I think the strips for the nose were similar, but they were only 1/8" wide.

I don't know the characteristics of ammonia. If I add ammonia, achieve the radius and secure the balsa so that the radius is held until dry.... is there a component of the ammonia that will be still be in the balsa? When water changes from liquid to gas there is nothing left behind. Does ammonia work the same way? Or do I even care, so long as it doesn't interfere with the CA?

I will give it a test and let you know.

Thanks for the comments!

Mike Roerig
[email protected]

Probably the easiest way to safely test this is using Windex with ammonia in it. That will dilute the ammonia and alcohol in the Windex will accelerate evaporation. Be sure to overlap your balsa as it will shrink back as it dries. CA is an acryl based product which might be effected chemically. When testing adhesion be careful to keep away from your eyes as it might evoke a physical reaction.

Here is a guy who says CA works with ammonia soaked wood. I'm sure I've used it as well but it's been a while because I normally use Aliphatic Glue when planking so it all sands easier.

http://www.myrc.org/Library/bldtip.htm

Don

Hi Mike, firstly to line the wheel wells with strips of balsa make your own long strips up from balsa cut from accross the balsa sheet, not along it. The balsa will bend very easily to the diameters you require if you soak them & bend them accross the grain, not along it.

Secondly, why bother? Air pressure build up may be an issue with fast flying turbine jets but for a slow flying electric model you seem to be spending a lot of effort fixing a non existant problem. Most full size aircraft just have big, open wells anyway so it will certainly look more scale like than neatly tailored pockets for the gear.

Do make sure you make them the correct shape, the 3 view will show you how. - John.

Amazing! Sometimes the simple, obvious solution is not so obvious!

Sure, if I cut the balsa across the grain it will be easy to make a 2.5" diameter arc. I just bought the ammonia this morning on the way to work. Oh well.

I agree that it isn't a requirement to close up the gear opening but I am trying to do my best to build a reasonably clean model. There is so much on this build that I haven't done before.

As of last night I am now completely online with plotting. My plots are now accurate within a few thousandths of an inch per foot so I can create a sheet of parts which will make building much easier. I have a 24" wide roll plotter (an HP DesignJet 600). It can plot a 24 x 36 sheet. I hope to be able to define a new sheet size that will allow plotting the entire fuse (82" long) or the entire wing (114" long) on a single sheet. These plots would be helpful as a guide when building.

With a few more evenings making CAD file updates I should be able to make a new set of plans available for downloading. There will still be a few updates later, such as servo / control surface updates, but if someone has a desire, they could start building a B-36 as soon as they like.

Thanks for the suggestion John!

Mike Roerig
[email protected]

Regarding the wheel wells. The B36 didn't have them. Just like Boomerang1 said, it was just an opening in the wing which the gear doors covered.

Thanks for the info guys, but it just doesn't seem right to leave it all open. The wheel wells would provide support for the edge of the wing skin and the ends of cut ribs.

I don't think I will need air flow in the wing for motor cooling since the nacelles should provide ample air flow. I really do appreciate the info but I still feel compelled to add the wheel wells.

Mike Roerig
[email protected]