The first photo shows the unsheeted fin and rudder built up. You can also see the top half of the fuse formers hanging from 2 balsa fuse spars. These 2 formers are made to put the stabilizer in it's correct location. Notice the leading edge of the fin is secured to the 2 fuse spars on top. It also secured to the 2 fuse spars on the bottom (can't see them in this photo). I have had a plane with a not so solid fin before, and I was trying to avoid that here. This plane is just too big.

The second phto shows the stabilizer adhered in place to the top half of the fuse formers. I was very pleased with the outcome. In this photo you can see the leading edge of the fin secured to the 2 fuse spars on the bottom.

The artwork in the background is a family portrait that my son did. A dad just has to display the good stuff.

Mike

I am not sure why, but there were a couple of extra photos in my previous post. The comments go with the last 2 photos.

Mike

The first photo is a side shot showing how the stabilizer fits in the tail section.

The second photo shows the start of sheetig the tail section of the fuse. The tail of this fuse is tapered so it is not possible to sheet with a wide strip of balsa.

Mike

The first photo shows how I used balsa strips to create the surface for the radar bulge. Don't be concerned about the rough surface. It sands smooth rather easily.

The second photo shows the sheeting moving along.

Mike

These photos show the fin tip being made.

Mike

The first phot shows the results of the first round of filling and sanding. It also shows that I have added 2 pieces of balsa for the radar bulge and the rear gun turret.

I added the second photo to give you a feel for the curvature of the bottom of the fuse.

Mike

I think this will be my last post for tonight.

I like the first photo because sometimes when I look at the fuse it looks big and heavy. This photo is a reminder of just how hollow this plane is. You can see that although the fin looks massive, it is quite hollow. FYI, the built up fuse weighs in at 3.0 pounds.

The second photo shows the beginnings of the wing saddle. I already have plans to change how I want to do this. I am working on the wing saddle now. I will add photos of the updated version when I finish it.

Mike

I was going through my folders of photos and came across a few nice ones.

The first one shows a huge B-29 (left) next to a B-36 (right). I have stood next to a B-29 and it is BIG.

The second and third photo shows the XB-36 which is what my design was trying to capture. I am now going with the more popular B-36 which has 4 wheel main gear and the easily recognized cockpit bubble.

Mike

I checked the weight of the fuselage of mine tonight, 2 pounds 15 oz according to my kitchen scales.

Keep in mind that is complete, painted, including the tail surfaces. Also in there is the nose retracts, leg & wheels, standard size servos for nose retract, elevator & rudder, reciever & 2 x speed controllers plus some other assorted goodies.

But, like I said, I tried very hard to keep it light.

The Discovery Channel featured the B-36 in one of their aircraft series, have you seen it? - John.

John,

At 2 pounds 15 oz, including the essentials, I think you did a great job of keeping it light. In fact I am sure that you did better than I did. I used very light balsa almost everywhere. I am not sure where I could have removed more weight, other than the sheeted skin.

There may be a bit of trimming that I could do, but I would be surprised if it removed more than an ounce or so.

Thanks for the info.

Mike

Mike what is the location of the fuselage supports? I didn't see them in the plans you have posted sofar and I think it would be a good idea to include them. I have been montoring you posts on the UK site and just now got a moment to get back into RC Universe. Its been a little hectic at work of late, we just found out we are being out sourced to IBM and my department will be rolling over to India.

I am sorry to hear about the IBM outsourcing. IBM always makes outsourcing look like a great deal. Lately I have heard that a few of their outsoucing clients have brought it back in-house. They just didn't work out. I have heard the same about the India outsourcing. Unfortunately people lose their jobs while companies learn. I could go on and on about this subject but I suppose I shouldn't do that here.


Back to the B-36.......

The fuselage supports were one of those things that I discovered were needed after I got in to the building phase. The carbon fiber tubing fuse spars run parallel to the fuse skin and your workbench so they can be placed anywhere you like. I believe that I put 3 of them in. They kept the fuse straight while I was building it.

I didn't think of the supports while I was designing the plane in CAD, but when I slid all of the fuse formers on to the carbon fiber tube spars I realize that I couldn't have it just roll around on my workbench. The temporary fuse supports seemed like a good solution, and they worked out well.

There are a few updates that I still need to make to the documentation, and the supports are one of them. The plans that I posted were posted a bit prematurely. I had a couple of the guys at work that urged me to get them posted so they could download them. At least that's what they said. I really think they just wanted me to get me going again on this plane. It has been set aside a couple of times. I am determined to finish it up.

I will also add some design drawings that show the cross section of the wing at specific locations of the wing. These helped me build the trailing edge of the wing. ( I am still not finished with the trailing edge )

I forgot to bring home from work the cable that allows me to transfer photos from my phone camera to my laptop so I won't be able to provide newer photos and comments until tomorrow.

This weekend I have been working on the wing mount and I have taken more photos. When it came time to building the wing mount I didn't like how I had designed it so I have reworked it. The new method seems to be working out fine. I will provide photos and update the design files. I hope to finish up the wing mount in the next few days.

So far I have heard only one flyer say that he will be building this B-36 next fall so I haven't felt rushed to get the design files updated right away.

I haven't heard anyone say that they downloaded the virtual reality viewer and viewed the virtual reality files ( the files with a .wrl file extension). I think these files would be a great way to review the plane before building one.

I would be very pleased to talk to a flyer that uses Unigraphics CAD software. That is what I used to design this plane.

This B-36 seems to have grown now that the wing is on the fuse. My workshop is 106 inche wide and the wing is 108 inches wide without the wing tips installed.

I sent the retracts back to Century Jet Models because I couldn't get them to fit within the wing. They replaced the air cylinders with different ones that have the air fittings moved to the side at no additional charge. The retracts will fit fine after that. Century Jet Models has been great to work with. They really want this plane to be successful. I know it sounds like a bit of a commecial but when you have a good experience with a parts supplier I think posting some positive comments is appropriate. If anyone decides to build this plane, mention that you want retracts for the Roerig 1/24th scale B-36 and you will get retracts that won't need any modifications. I expect my retracts to return tomorrow and then I can finish mounting them.

I hope to get the motor mounts installed later in the week. These will be changed too. I originally planned on using 6 geared speed 480 brushed motors and I have changed to brushless motors. I found some nice motor mounts that were 6 for $10 so that is what I will be using. The motor mounts have printing on the side: EMM 28A GWS. They are very light and will simplify mounting the motors. This will be another update to the design files.

Overall I suspect that I have a few evenings of work to get the design files updated with the recent improvements. FYI, the build file will show photos of the changes.

Mike

If you don't mind my asking how expensive were the retracts? I want to see if they will fit my budget. I may go the single wheel route and find some off the shelf mechanical retracts or try going fixed gear to start with.

Mike

My original design was for the XB-36 which has the single wheel main gear. I had planned to go with fixed gear. There are photos of the XB-36 in previous posts.

The Century Jet Models retracts for this plane were $462 for a complete system. That included the 4 way valve to make them open and close slowly like they should. I think you can shave off $40 if you pass on the 4 way valve. I don't know if the $462 was because mine were custom/prototypes. You could always send them an email.

Mike

I haven't updated the build doc yet, but I will TRY to get to that tonight. I do need to spend some time building, and also spend some time with my wife if I want to stay married.

I mentioned in an earlier post that I sent the retract mechanism back to Century Jet Models so they could change where the air line connects to the air cylinder for the main gear. You have probably seen enough photos of the landing gear, but I thought that I would add two more that shows 4 wheel bogey setup. I think these photos could be valuable to someone if they build this plane.

I will have to wait another day to fit the retracts. No retracts in the UPS delivery today.

Mike

Since I was waiting for the retracts to return, I needed to work on something else. I need to finish up the trailing edge of the wing before I work on the motor mounts (remember this is a pusher). I have also wanted to start fitting the wing to the fuselage. I have known for some time that I wasn't happy with the way I designed the wing mount. But before I could try fitting the wing to the fuselage, I needed to have the trailing edge built up in the root area of the wing.

I looked at the little pieces that I had cutout for the trailing edge at the root rib area and as you guessed it, I changed how I wanted to do it. I knew that I was changing the wing mount but I didn't know how much strength this area would need to have when I finally figured out the wing mount. So I pulled out a block of very light balsa, cut it to a very approximate shape and adhered it to the trailing edge of a wing half.

Working on the top side of the wing I started shaping the solid piece of the trailing edge. When you build a kitted plane, all of the parts are cut out for you so there usually isn't much shaping required. When I got to the trailing edge of the wing I realized that I needed a guide to help me get it right. So I opened up the CAD drawings and created drawings that showed the cross section of the wing at certain locations. I will add these to the design files. I used the drawings to create templates.

I found that the shape of the bottom side of the wing would be easy to create if the bottom side of the wing were sheeted. I can't sheet the bottom side of the wing just yet because I still have a fair amount of work to do inside the wing. My solution was to sheet the first 3 ribs. The second photo show the bottom side of the wing with the open ribs. You can imagine that getting the shape of the trailing edge without the sheeting would be very difficult. I need this trailing edge to be complete so that I can work on the wing mount area.

The first photo shows some of the templates that I made.

The notebook in the background of the second photo is the collection of part drawings for this plane. They make good reference.

Mike

Hmmm..... no photos.

I will try to upload them again.

Mike

Now that I have a trailing edge to work with, I can begin to create a wing mount.

The first photo shows the area where the wing mount would go. The flat horizontal oversized rails are basswood. I am cutting them down with a dremel tool to reduce weight. I thought that I needed some extra strength here so I used basswood.

I started the wing mount with 1" thick very light balsa blocks and lightly CA'd them in to place. I hope that I can free this up without much damage. This is shown in the second photo.

The next two photos will be in the next post.

I carved away quite a bit of these 2 pieces and then added 1" thick very light balsa at the ends. I am still figuring it out, but I believe that these will be used to hold the wing to the fuse. I can lighten up all of these pieces later when I get everything figured out. The end blocks can be seen in the third photo.

I began to shape these pieces to match the contour of the fuselage as shown in the fourth photo.

Mike

Two more photos from the previous post.

Mike

I placed the wing on the shaped wing mount as shown in the first photo.

I pulled the wing halves apart to reveal about a quarter of an inch space between them.

I ran a string down the center of the fuse. This string would show me how the top of the wing would blend in to the fuse when I finish up this area. There is a small area on the top of the wing that should protrude above the fuse. The second and third photos show the gap in the wing, and the string passing through that gap. Look closely, the string is hard to see but it is there.

With the wing in place, I marked the side of the wing mount and carved it away. I did this in stages so that I didn't get the wing dropped down too far. I have it close enough now to start sanding the wing mount for a better fit. This sanding will drop the wing down just a bit further. You can see that in the fourth photo.

The fifth photo shows the wing mount carved roughly to shape. I will probably need to add some width to the carved area to distribute the load.

I think that is it for tonight.

Mike

Here is the wing mount area carved roughly to shape.

Mike

I have been busy the last few days tracking down a problem with my laptop so there has been only a bit of progress.

Well, it seems that the next step was to sand the wing mounting area to be a bit more accurate. My plan was to place the fuse on a flat surface and then place the wing on the fuse and measure the distance from wing tip to floor. I was going to sand the wing mounting area until the wing tips were at an equal distance from the floor. My workshop is too small so I brought the fuse and wing in the house to the basement. I used a square to confirm that the fin/rudder were perfectly vertical. I then placed the wing on the fuse and measure the distance from the wing tip to the floor. I was pleased to see that there was only a one inch difference. I removed the wing and sanded a little and put the wing back on the fuse. I repeated this process a few times but I couldn't seem to get it right. Eventually I realized that with each wing halve extending 54 inches, even the slightest shift of the fuse would cause the distance from tip to floor to change dramatically. I decided to change how to do this. Since the retracts have been returned from Century Jet Models, it seemed logical to mount the retracts and extend them. The wing should be level so then I would need to sand the wing mount until the fin/rudder are vertical.

In the midst of my attempts to sand the wing mount to get the wing level, I realized that the wing wasn't sitting positioned where I expected. The photos and drawings show the top side of the wing protruding just a bit above the fuse and it seemed that I had it just a bit too high. I went back to the CAD files and obtained some measurements that I will need to add to the docs. The reference for these measurements is the rear, bottom, center of the wing mount. Here are the correct measurements: The distance to the point where the trailing edge of the wing halves meet is 1.9" forward and 0.7" up. The distance to the point where the leading edge of the wing halves meet is 17.75" forward and 1.5" up. You can see that the leading edge of the wing is higher than the trailing edge ( elevation of the trailing edge is 0.7" and the leading edge is 1.5" ).

I used these measurements to discover that I did not have the wing in the proper location. I carved the wing mount to get it closer to where it should be as shown in the these photos.

Mike Roerig
[email protected]

Here is a photo of the wing sitting on the roughly carved wing mount. Even though I had to rework this area, I was pleased to have a larger surface area for wing to rest on. I still plan to add more support to the bottom side of the wing.

The next two photos show how the position of the wing has moved. I will get this position a bit more accurate after I finish up the retact mount as described in a previous post. In these photos you can see a black dot that I put on the wing mount to help me locate the wing.

Mike Roerig

[email protected]

This photo (a bit blurry) shows the retract mounted in the wing. You can see that one of the air fittings has been moved to the side of the air cylinder. Later I will need to put in a bit more work to this area.

Mike Roerig

I thought that I should add one more post regarding files for download.

The RC'er that volunteered to make space available to host my files for download came through as promised. I took a look at the site and I quickly realized that my files need some organization. If you recall, I mentioned in one the first posts that these files were made available before I could organize them so I guess I will use that as an excuse for now.

Another RC'er volunteered to clean up my build doc and convert them in to smaller pdf files that will make downloading them quicker. The smaller build doc files can also be posted here on RC Universe and on RCMF. He has sent me the first two files and they look good. I will get them posted shortly. It takes time to keep the docs in order and post updates here and I still need to get some time to work on the plane or there won't be anything to post. Updates to the build docs will be available soon and I will provide a link to the web site for downloading them.

Mike