I was planning on having the landing gear equipment and bays installed for this update but that didn’t happen because when I carefully examined the wings, I discovered that I had made a pretty significant error.
You can see it pretty distinctly in this photo:
As you can see the both the leading and trailing edge spars on the right wing half are about 1/16 ” forward of where they should be and don’t align precisely with the spars on the left wing which are in the correct position.
This was a MAJOR problem because when the wing halves are ultimately joined together, the joining is accomplished through the use of “jig” like locking plates that require the spars to be precisely aligned.
After looking at both the right and left wing carefully, I could see that the spars on the left wing were, in fact, in the correct position. However, on the right wing, the spars from the inboard edge to a point about 9 ribs out were curved to the point where the misalignment was greatest at the inboard edge. This probably occurred because I wasn’t careful enough when I installed those wing ribs and I pulled those spars out of position. It’s easy enough to do; this is PE, after all, and it’s pretty springy stuff.
Note, in the following photograph where the spars get a curved look about 8 or 9 ribs out:
Well, there was good news. It’s just PE and CA glue, so it can be debonded and the position corrected. And, that’s precisely what I did this past week. It uses a fair amount of debonder because you have to soak the joints in enough of it to make them let loose, and also you need to clean up any CA from the joint which is still there so that the ribs/spars look like new.
So, it’s perfectly aligned now, and no permanent harm done, but it’s a cautionary tale about how one of these types of kits can get away from you in a big way as a small error multiplies on itself.
So, I’ll starting on the landing gear today and here is a photo of the parts for both the left and right gear, wheels, tires, associated ribs and walls of the landing gear bays. I puzzled long and hard over these parts from the “J” bag because many of them are almost identical because (1) the right gear and bay are a mirror image of the left, (2) the aircraft can be assembled in either an “in-flight” configuration, or a landing configuration, and (3) the diagrams in the instructions are so poor, it was impossible to actually identify which of the parts to use for the correct side and correct configuration.
Those first two pages of the assembly manual saved the day yet again with careful diagrams and part numbers for those in question, and in a matter of 15 minutes, I had the stuff organized and ready to build, which is where it is now: (Note, yet again, my written notes for the parts to help keep them organized)
OK, so I’ll be slogging through the LG for the next little while, but progress will accelerate a bit since most of the cockpit parts are now painted, and there is still a lot of straightforward building work involving just PE, white metal, and no painting at all.
Finally, I can get back to work on modeling! I did a video on my work space for Phil and you can see it in the work space videos or in his weekly report for 14 March 2014. Hope you will give it a look if you haven’t already and enjoy seeing my work spaces.
On the Fine Structure Zero, it was landing gear time this week. The landing gear itself, installing the landing gear in the wings, and installing the landing gear bays… We are going to cover all of these in this report as well as talk a bit about how to do a cleanup process on these Fine Structure models, and review a couple of products which are new to me.
Building the landing gear was a bit sporting. As I think Peter pointed out that it might be. Whenever you are working on a joint between stainless steel PE and white metal, it can be difficult to make it do what you want it to do. One major factor is the flat nature and “springiness” of stainless steel PE. It’s difficult to get a good mechanical join with the uneven surface and imprecise casting of the white metal parts. In this part of the build we had 7 PE-white metal CA joints to do for each strut, one of them load bearing.
So, I’ve got some general advice for you when tackling this kind of build.
First of all, when gluing white metal flat surfaces to flat PE surfaces as in the case of the main landing gear mount, gel CA is your friend. The same is true for white metal to white metal joins of which there are a number in the landing gear. It’s much better to use gel CA than to mess about with thin stuff trying to get a good join.
Second, take extra time to dry fit and file and sand as necessary to get the best possible ‘flat’ joins that you can. The more time you spend dry fitting and correcting here will pay major dividends in the strength of your joints. In the case of the actual joint between the leading edge wing spar and the landing gear mount, you may have also have to use some CA debonder to clean up any excess glue that may be left in that area to get a truly flat joint.
This dry fitting and filing/sanding process is really a great practice to get used to doing as a matter of course on any model. It’s just one of those fundamental skills that we sometimes pass by in favor of putty!
So, after assembly, we had left and right main landing gears that looked like this:
And, note the scissors jack, strut cover, and wheel cover mounting pieces that are all PE to white metal joins in this view:
To begin the process on both left and right wings, we install the rear half of the strut and wheel well bays. The following photo shows the parts laid out on the instruction sheet and I hope you can get some idea of how puzzling this step was. The real message is to study the parts carefully, and THINK about how those parts fit together before you put CA to metal. As is often the case in these Fine Structure kits you can find yourself wishing for a third and fourth hand while trying to wrangle too many parts that all want to move at the same time.
After that’s in place, the landing gear assembly can be glued between the ribs and onto the leading edge spar as shown. Once again, be sure that the joins are as flat and as clean as possible. This is one of the few load bearing joins in the model and it needs to be strong. Like this:
Next, we complete the assembly of the landing gear bay by gluing the front wall in the matching slots on the tops of the wing ribs. This fits exceptionally well, and you shouldn’t have any trouble at all getting it just right.
Finally, the top of the wheel well is glued in place; another very good fit. But, also one where it’s easy to leave behind a “CA fingerprint”. You know, where you glue yourself to the model. I’m sure you’ve already done it at some points in this build, so let’s talk about how to get rid of them, because you’re going to want to do final cleanups when you finish the wing halves, fuselage, etc.
It’s easy. All it takes is some debonder and micro brushes. Please, don’t consider doing this with anything that isn’t disposable; you will completely ruin a regular brush, for example, by having it soaked in a mixture of debonder and dissolved CA
Here’s a photo of one of my missteps on the wing bottom skin, in particular, a glue fingerprint on the surface of the PE.
Use a microbrush dipped in debonder and gently scrub the area keeping the brush pretty wet, and changing it if you need to. As you notice less and less of the residue remaining, start making all of your strokes in one direction to keep from spreading the solution all over the place, and finally, blot it dry with a clean paper towel. It’s a very quick and easy way to end up with a beautiful stainless steel skin on your project:
I happened to be reading an article on another website about a different Fine Structure build using a kit from a different company. The author there was very enthusiastic about a CA product called “KISS Maximum Speed Nail Glue” which claims a setup time of 3 seconds without using an accelerator. Probably a great product for a manicurist.
I gave it a fair tryout on some of the joints in this part of the build and found that the setup time claim of about 3 seconds is, indeed, true. Also, you don’t seem to need accelerator. BUT, in my humble opinion, I don’t think that the joints are as strong.
And the cost difference is huge. KISS comes in a 0.1 oz (3 g) container which costs about $3.31. That works out to $1.10 per gram or (at the current exchange rate) about .66 quid per gram. I like a “fast” CA which is used by a lot of RC modelers here called “Instant Jet” which I buy in a 1 oz (28.4 g) container for $6.19 or about .22 quid per gram; one third the cost.
And, I’ll end today’s report with a review of a CA tool that I’m really liking a lot.
It’s called the Glue Looper, Version 2. It comes on a card with 4 of each size loop included and you can clean the tip frequently just burning off the hardened CA with a match and fits in a standard hobby knife handle.
[Photo of Glue Looper, V2]
Version 1 was only half as thick, and very fragile. It was easy to bend the tip just by a gentle touch. Version 2 is a lot tougher; tough enough to win me over as a convert to this brand for thin CA applicators.
The only real drawback to the product is that I think it’s outrageously expensive, but I like it well enough that I’ll use it anyway. It’s available from Sprue Brothers for $13.49 or about 8 quid.
At the beginning of this build, I was recommending RB Productions liquid gluing tool, and I still like it a lot, but I think it works better at slightly thicker liquid viscosities. There is a photo of it back in Part 1 of this build. I’m sure that there are many out there who will prefer Radu’s product over the Glue Looper. RB Productions product is available from them (http://www.radubstore.com) with 5 on a card for about 5 euro.
That’s all for this time. Up next, I will be building and installing the flaps and ailerons, completing the cockpit painting and assembly as well as the mid-fuselage assembly, followed by the rear fuselage, horizontal stab and elevators, vertical tab and rudder. A few final touches, and we will be done.