Kwik Fli 40

[Martyn K]

Thanks Simon

I have a couple of 120FS engines lurking so I have scaled the original up to 69" span to see what it looks like. Unfortunately, the OS 120FS Surpass fits perfectly so I guess this will go on my build list for when I have spare 3 months or so. Interesting exercise. Not one I am suggesting for the Mass Build though.

This will definitely have Beech block undercarriage as well

Martyn

[Martyn K]

Well, I have made a start:

Tailplane no 2 and 3 outlines. No 1 was scrapped because I used a 3mm balsa frame and I then decided it wouldn't be strong enough. This version (and as drawn on v2 of the plans) uses 4.5mm balsa. After I built the second one, I decided that spruce doubler didn't need to be quite so wide so was reduced to 6mm width. In place development is not the best way to work..

You can see that one (for the KF4) has a Kevlar hinge. For the KF3 version I will be using traditional hinges as I suspect that most people will use these.

With 1.5mm light sheet added - top and bottom and the LE rounded to shape. Elevators, Fin and Rudder next.

The v2 drawing are still WIP. I am extracting all the laser cut parts (formers, ribs etc) onto separate drawings to make the build process easier. Hopefully, I will get them done for the middle of next week.

Here are a couple of jpgs that show where I am up to.

KF3-40

KF4-40

Quite a few minor changes to drawing v1 including a slightly stronger u/c mounting - still on ply plates though

More to come.

Martyn

P.S. Just to be clear, this is my Mass Build project - whether it is selected or not!

[Martyn K]

I have a question for the 'E' variant. Assuming a rear mounted motor attached to the front of F1 - normal practice. However, I need to attach the noseleg to the rear of F1 and I am not sure whether a 3mm birch ply former will be strong enough and what method is used to prevent the bolts securing one interfering with the mount of the other. I could offset the noseleg but not really happy with that idea. Alternatively, I mount the noseleg (using saddle clamps) above and below the motor mount..

Any thoughts on this?

Martyn

[IanN]

Posted by Martyn K on 28/10/2016 14:28:16:

I have a question for the 'E' variant. Assuming a rear mounted motor attached to the front of F1 - normal practice. However, I need to attach the noseleg to the rear of F1 and I am not sure whether a 3mm birch ply former will be strong enough and what method is used to prevent the bolts securing one interfering with the mount of the other. I could offset the noseleg but not really happy with that idea. Alternatively, I mount the noseleg (using saddle clamps) above and below the motor mount..

Any thoughts on this?

Martyn

Considering that exact same q for a Flea Fli build. Rear mounted motor mounted to front of F1, noseleg mounted centrally - no offset - to rear of F1 with saddle clamps

Having been through the "box of bits" and done a dry run over the plan I think it's poss to do that in a way that they don't interfere with each other. If one or more of the bolt holes look too close for comfort, and suggest that F1 might be unacceptably weakened, I'll bend or adapt the upper part of the noseleg to suit

[Martyn K]

its quite tricky isn't it? I don't want to weaken the former/bulkhead either. I did wonder if mounting the noseleg on 6mm hardwood blocks behind the former may be a better approach. These could be screwed to the bulkhead with c/s screws and then the saddle clamps screwed into the hardwood block

Martyn

[McG 6969]

Sorry Martyn,

I'm really trying to follow your ideas as a modeling newbie.

IMHO, a Mass build should be a 'ready-to-go' product to attract as much as possible 'new blood' in the hobby...

You are adressing yourself to evolved builders with an understanding of what you're talking about and that's not the idea of making of a product 'public to the mass' .

Don't misunderstand me, your technical approach is not at all involved, but you're missing the MB-point of it all. Sorry again.

Good luck with your project, Sir.

Hakuna matata

Chris

BRU - BE / CTR MB Control

[IanN]

McG, re your "you're missing the MB-point of it all" comment I have to say that, with genuine respect for your views, I think that with that phrase it is you who are missing the point - by several miles

The Kwik-Fli has been around for 50 years, been successfully built in large numbers, and is of relatively simple construction by any reasonable measure or comparison. It's a perfectly suitable MB project, made more attractive by the wide range of size and power options being proposed, and significantly less complex than a no of others that have been suggested

Martyn is simply seeking a consensus of views on one fairly simple aspect of construction in order to arrive at the best solution, and in so doing to get as close as possible the very thing that you yourself are asking for - your " 'ready-to-go' product to attract as much as possible 'new blood' in the hobby." An aspect that - whatever he personally decides on - will in real life in any case vary from builder to builder depending on what hardware they have to hand.

What Martyn is asking here is absolutely in no way any different to any of the "run of the mill" qs that come up during the course of any mass build. No plan or build is ever "one size fits all" and whatever plan is published will not (and cannot possibly) be perfect for absolutely everyone. In this particular case, my motor mount may have different hole spacings to yours. The noseleg you bought from your LMS may be a better fit than the only one that I can lay my hands on. Etc etc

In a lot of ways, that IS the whole point of the mass build. People share as they go, help each other out, and everyone learns and gains experience

[McG 6969]

Dear Ian,

As I already mentioned in my post, Martyn’s work on the subject is really not involved, nor his dedication and abilities. I could only wish mine were at that level.

And I would never argue about a winning Kraft design neither, of course.

My point - and it strictly remains ‘my’ opinion - is purely that the ‘project’ is not yet ‘Mass-ready’ for this winter build. Following last MB which started on January 1^st, one of the ideas from participants was to start the build earlier - around Christmas holidays - to allow to ‘fill in’ that period with some building. Really not that much time left for building the prototypes, maiden them when/if weather allows, potentially have some corrections made and finally ‘publish’ some drawings for both… all that in the next six weeks…

Another point is the term ‘Mass’. In my home country, the Mass is democratically allowed to vote for an idea or project, but I can’t remember seeing a vote initiated for the MB 2017, so I’m a little afraid that by lack of interest, there won’t be a MB at all this winter.

Busy now walking back those “several miles” you mentioned, to see if I can find back my “missing point”…

Hakuna matata

Chris

BRU - BE / CTR MB Un-Control

[IanN]

Chris, please don’t wear out too much shoe leather on my account, I wouldn’t want you to have to buy a new pair

Your post was in response to Martyn’s q re how best to bolt the hardware to F1, therefore I thought it was fair to assume it was that particular specific point that you were referring to. It seems I may have been wrong in that assumption (sorry!) as I if I understand your response correctly I now see that your concern is rather that the whole KF40 “‘project’ might not yet be ‘Mass-ready’ for this winter build.” Ok, no problem with that: its a fair enough q to ask but imo I still think it’s wide of the mark, and would offer the following reasons to support that opinion

• Martyn designs, draws and builds at a prodigious rate. Look up his Kwik-Fli IV on this forum – from scratch to finished and ready to go in just over three weeks, including own cowl moulding and cutting tapered foam cores. Imo that’s impressive

 

• We know the Kwik-Fli is an easyish build, already evidenced by the original, the Flea-Fli and the Flea-Fli + 10%, all of which have been around for a very long time and built in numbers. The KF40 doesn’t deviate from that proven and tried and trusted construction. Not seeing where there is going to be any problem at all here

 

• There is admittedly the issue of getting test flights in, given the autumnal season that we are now in but …..

 

• Does anyone seriously think there is any remote chance that a KF40 won’t fly well enough? It’s a very well proven design and layout, on which tens if not hundreds of .40 sized club aerobats have been based, or are very similar indeed to

 

• In any case, if for any reason Martyn isn’t 100% happy with it I’m pretty sure he would be the first to pull it. (That would of course still leave the existing Kwik-Fli variants as a potential candidate for selection any mass build - the KF40 is simply an additional "nice to do" option that broadens the appeal of the Kwik-Fli family)

Re your more general point “I can’t remember seeing a vote initiated for the MB 2017, so I’m a little afraid that by lack of interest, there won’t be a MB at all this winter”, on checking back I see that the voting for the 2015 MB started on 16/11 and 2016 MB voting commenced on 7/11. So, we’re still in the ballpark for that to happen.

I suspect this is where a gentle steer from BEB is going to be needed

Edited By IanN on 30/10/2016 11:49:39

[IanN]

Also should have said above - but forgot - that the point about voting for the 2017 choice is a bit "off topic" here and probably belongs in with the general "2017 Mass Build" posts. This is, after all Martyn's Kwik Fli 40 thread

[Martyn K]

Apologies for the delay responding, Chris has made some valid points and I would like to add my thoughts.

Firstly, there isn't a MB2017 model yet. It has been suggested for very good reasons that the Kwik Fli (especially the KF3) would make a good model. I have to agree. I also stated that I thought that the Flea Fli was a little too small and the standard FK3 was too big - especially for an electric conversion, it would need a lot of work doing and the power train would be expensive, I suggested - perhaps a little hastily - that I could rework the original plans for a 40 sized model and do a designed for electric variant. I have already done similar activities - the Curare for a 25 and Hanno Prettner's wonderful Mystic for a hot 40. Both have been successful conversions and I enjoy the twist to building these wonderful classic airframes at different sizes.

In many respects, the KF3 is (IMHO) a better model for a first time builder than the Ballerina. It is certainly easier to build and due to the measurements and structural layout probably makes an easier electric conversion.

There is no essential redesign, I am trying to make the construction easier and clearer than Phil Kraft did in 1967. Materials and methods have changed and providing the flavour doesn't change too much then the spirit of the original design can be easily maintained. By taking out some of the complexities like a steerable nose wheel (which isn't needed, these models are so light on the main wheels that you can easily steer them on a fast taxi on rudder alone). Phil Kraft also had brakes on his original - somewhere else I am not going to go.

I agree that to draw this up AND produce CAD drawing accurate enough for a kit is a challenge. I also didn't really want two KF3-40's one for E and one for ic. So I have drawn a KF4 as well. With its tapered wing and slightly more lively handling, this may appeal to more experienced modellers - bearing in mind that the rest of the airframe is almost identical. By now I realised that I really need ic and E versions of that so we now have 4 variants. I am not building 4 models for this... However, by proof building one ic model and one E model of each I hope I can identify any shortcomings in the drawings and more importantly the DXF files required for cutting. I am already in discussion with one laser cutter who has agreed to do a parts cut - most - not all of the parts, but I hope that with a little ingenuity and my demonstration KF3 build you will see that a laser cut parts list is not required. The KF4 with its tapered wing would benefit from a full wing kit at least and that will be available in due course.

Finally, I don't really care if the model is selected for the MB or not. At the moment, there is a lot of interest in the Skywriter, something I may build but do I think this is a suitable first build model - absolutely not - 2 wings is more than twice as complex as a monoplane.

Those who know me are aware that I am a founder and administrator of the UKCAA. These wonderful classics are a joy to fly, mainly very easy and if built light perform far better than their original designer would ever have imagined. By reworking and making these designs freely available, I hope to encourage others to see this for themselves. If one other person build a KF-40 then the exercise has been more than worthwhile

[Martyn K]

Build progress. I started work on the model last week - in fact I started work on both models last week with the construction of the tailplanes. I am planning to do a single PDF for each major component of the plans, optimised so they can be tile printed to minimise printing costs.

Back to the tailplanes:

One of the tailplanes uses a Kevlar hinge - me preference, however for the KF3, I am going to proof build using conventional hinges - There is dedication for you. The structure is very simple. 3/16 or 5mm balsa outline with 'ribs cut from 5x3 balsa. Sorry if I keep mixing units. I drew the plan in metric and the wood arrived in imperial. Note that since v1 of the plan, there is a LE doubler and the spruce brace has been reduced in size

Sheeted with very light 1.5mm balsa and sanded to shape. Much as I dislike flat plates, this is what these are but it makes sanding to shape a much simpler task

Fuselage parts were marked and cut from the DXF files to check the accuracy, Laser printed parts sheet is placed on the wood face down and damped with a little cellulose thinners to transfer the image. You can thank Andy Sephton for that tip. A poor mans laser cut parts set (ie hand cut) was created, there are only 3 parts needed to get the fus started - in 3 different types of wood.

Engine mount and bulkhead drilled and captive T nuts fitted. A dry check that the parts slot together correctly over the plan identified the first minor drafting error, F2 was 2mm too far back which will be corrected on the plans in about 30 minutes.

The four balsa formers from 9x3 balsa simply glued as a frame.The corners are cut to size to fit, but should (if the triangle is the right size) be a simple diagonal saw cut across the intersections of the vertical and upper cross members. Slots for 3mm square longerons are again cut to fit as the fuselage is assembled

The fuselage sides are 1m long - not good if you have only 36" balsa to use so I had to scarf join the extra at the front using much harder balsa for the nose area. Marking out is an absolute doddle. The rear section is a triangle with the point cut off - all straight edges. The upper edge of the sides is a straight line to F2 - and is also the datum. All incidence measurements can be taken from this line. Mark the location of the formers on one side only. 

The 1/32 ply doublers were marked using carbon paper and then upper triangle, lower longeron and doubler glued, assembled and allowed to dry. I also took the opportunity to glue in F3 and F2 making sure they were both vertical (to the datum)..I should also have fitted F4 as the Fus is parallel between F2  and F4

Edited By Martyn K on 01/11/2016 22:21:12

[Martyn K]

continued

The batteries ensure that the ply doubler doesn't lift and also that the formers stay vertical

This evening the fuselage sides were placed in a jig, carefully aligned and F1, the fuel tank base and the rear formers (F4-F6) cut and fitted. Fith the fuselage assembled upside down (on the datum), it is easy to check that F1 is vertical and also no inadvertent side thrust has been added

The fuel tank base - lots of clamps ensuring that good joints are maintained. The elastic bands prevent the jig arms from splaying which they tend to do if not careful.

Fitting of the 4 rear built up formers, You can see how the wood has been trimmed and fitted. You need to make an allowance for the ply doubler which crosses F4 at about 50% height. I now know that it would have been easier to do that before the fuselage went in the jig..

One thing I forgot to photograph.. The rear doublers (around the tailplane) are cut from 3mm balsa but cut slightly too wide then chamfered on the upper edge to fit into the triangle. The tailplane is set at 0 degrees to the datum, so the slot for the tailplane - which is conveniently located on the lower edge of the triangle can also be cut. Leave the fit rather tight at the moment to allow for any last minute adjustments.

That's it for tonight, more to come.

Martyn

[Paul C.]

Hi martin, is the KF4 with the tapered wing a 40 size plan ? Going to start with the flea fli as I have the power train available a larger variant could be next on the list would prefer the tapered wing If possible.

Paul.

[Martyn K]

Hi Paul

Yes - that will probably be available in the next few days, You may want me to proof build it first though I have a standard sized KF4, its a very nice flyer indeed, one of my favourites

Martyn

[Paul C.]

Thanks martin, I am in no rush as I am not the world's fastest builder. Put me on the list for a plan when you are happy with it 👍

Paul.

[McG 6969]

Hi Martyn,

As I already mentioned twice in my posts/answers to Ian, your work on the subject is really not relevant to my reaction, nor your dedication and abilities. I could only wish mine were at your level.

What I was worried about is the ‘timeline’ to get everything ready for a potential MB 2017. That’s all I was concerned about.

Due to my native language, I’m visiting a lot of French forums as well and I found a ‘guideline to contemporary building’ improvements by Christian Chauzit, the - at that time - ‘quite young’ designer of the Baron during the sixties. In fact, he redesigned his own concept with nowadays methods & materials in 2015. It’s amazing to see the different approach with mainly ‘laminates’ of different materials to win some weight and even being stronger.

For example, as you seem to have a question mark related to the strength of your bulkhead/nose wheel anchor, why not laminating a piece of 1mm fibreglass (circuit board) or thin aluminium between two thin ply formers?

Anyway Martyn, I only wish you all the best with your dedication to this project.

Hakuna matata

Chris

BRU - BE / CTR Improvement Control

[IanN]

Posted by McG 6969 on 01/11/2016 22:53:38:

Hi Martyn,

As I already mentioned twice in my posts/answers to Ian, your work on the subject is really not relevant to my reaction, nor your dedication and abilities. I could only wish mine were at your level.

What I was worried about is the ‘timeline’ to get everything ready for a potential MB 2017. That’s all I was concerned about.

Due to my native language, I’m visiting a lot of French forums as well and I found a ‘guideline to contemporary building’ improvements by Christian Chauzit, the - at that time - ‘quite young’ designer of the Baron during the sixties. In fact, he redesigned his own concept with nowadays methods & materials in 2015. It’s amazing to see the different approach with mainly ‘laminates’ of different materials to win some weight and even being stronger.

For example, as you seem to have a question mark related to the strength of your bulkhead/nose wheel anchor, why not laminating a piece of 1mm fibreglass (circuit board) or thin aluminium between two thin ply formers?

Anyway Martyn, I only wish you all the best with your dedication to this project.

Hakuna matata

Chris

BRU - BE / CTR Improvement Control

[Martyn K]

A little more progress.

The upper deck has been added and roughly planed and sanded to shape. Final sanding will be done when the front hatch is fitted later today.

Sorry - not very sharp

1/32 ply facing on the hatch edge.

Glued and allowed to dry thoroughly before its finally shaped

The inner edges of F1, F2 and the fuel tank base are reinforced with triangle

On the E version, the fuel tank base is replaced with a LiPo tray that sits slightly higher in the fuselage and extends back to F3. This space - below the LiPo - will contain the ESC.

A small length of hardwood is fitted across the top of F1 . This will be used to either a) - have a screw fitting for the fuel tank or b) have a catch for the LiPo access. The E version F1 will sit slightly further forward (about 10mm - and is reduced in size to maintain the same profile) and will have a slightly bigger hatch. This way, the prop will be in the same location for both the E and ic versions.

In reality, F1 has actually been moved backwards by 10mm on the ic version...

The fin parts (for both versions assembled from 1/4" balsa

Unfortunately, both fin and rudder are just slightly wider than 4" so need to be extended slightly. The anti warp strips top and bottom can be seen. Left overnight to dry

The fuselage engine and tank bays got a coat of fuel proofer last night - it will get a second coat later

... and this morning, a test fit of tailplane and fin

and it all looks nice and square as a bonus Definitely got that Kwik Fli look

I am still working on the KF4 plan at the moment, but the next thing to do is get this fus finished

I'll build the KF4 fus as electric and then make a start on the wings.

More to come

Martyn

[Paul C.]

Hi martyn , off on hols for two weeks tomorrow 😎 looking forward to see your progress when we get back. You will probably have three in the air at the speed you are building 👍

Paul.

[Martyn K]

Enjoy your holiday Paul. I hope the KF3 will be finished (or very nearly) by the time you are back - the KF4 may take a little longer as I will have to wait for the laser cutter

Martyn

[Martyn K]

A bit of progress, not as much as I would like as I have been away (work) for a couple of days and was not too well over the weekend.

Firstly, the KF3-40 Fuselage and tail have trued and glued.

There is also a hatch and a 10oz fuel tank installed (loosely). The hatch is located at the rear by 2 x 2mm pins (cut from a length of pushrod). I'll use a screw to secure the front end of the hatch. It shouldn't need to be undone too often

and the fin and tailplane. The rudder has been separated and is hinged but hinges not glued yet

So I started work on the KF4-40

A test fit of the E crutch identified a couple of minor errors which have now been corrected on the drawing

This is what I did to mount the nose leg. 3 beech blocks glued to the back of F1 and saddle clamps to hold it together.. The long block at the base will be back screwed from the other side as this will take most of the landing loads. The other two blocks are in compression under load.

The fus back in the jig and two errors recorded. One was a stupid builder error - one fus side was displaced backward by about 1.5mm (which I didn't spot - it was on the wrong side of the jig and slightly hidden by the front SLEC clamp) so didn't sit flush against the front of F1 and the second one is that the liteplay base for the battery box is 5mm lower than expected, sitting on the top of the wing rather than above the F3 cross member. I need to investigate that one. Not too worried about it as it gives more space, but it was still unexpected.

What was nice was that the wing mounting plate and sides fitted perfectly. This and the equivalent in the wing were drilled as a pair but using the hole marking transferred from the pdf print. I am using M4 Steel Cap head bolts to secure the wing. The plate is wide enough for an M6 Nylon bolt if needed

In the next photo, 5mm sq balsa rails in the lower compartment to support the curved ESC access hatch - which will be screwed into place

The next unexpected unplanned oops. When I planned the layout I didn't allow for the motor crucifix mounting screws which unfortunately lined up perfectly with the battery tray. I need to have a think about this, but the first lightning hole will be moved backwards to allow for this eventuality and also a slot is needed for the U/C leg. All very hairy as it was cut in situ and the liteply has a very thin layer of paper attached - don't ask - which are the hairs that you can see

Close up with modified plate for my version. The saddle clamps can be accessed and screws undone.from inside the fuselage.

This shows the rear of the LiPo plate and how it now sits just on top of the wing...

Additional work done since the photos.

Some of the hairs have been removed

I have triangulated F1 and the LiPo tray corners and added the upper deck, planed and sanded it and I am just about to align and glue the tailplane and fin. Need to add the elevators first though as I am using Kevlar hinge - I'll bet I forget to do that bit...

More to come.

Martyn

[Martyn K]

A tale of two cowls and a wing

So - my full sized flying lesson was cancelled yesterday which effectively gave me a full day in the shed as wife and no. 1 daughter chose to go Christmas Shopping instead. Its amazing what you can get done in a 6 hour stint

Both fuselages were brought to the same state. Elevators fitted to the KF4 and tailplane and fin glued into place on Friday evening (IIRC),

Saturday was then spent working on the cowls and the KF3 wing...

On the E version - which has a slightly longer fuselage, a lite ply back plate and 1/32 ply disk behind the spinner (with a thin card spacer)

The sides were simply boxed in using 3/8 soft balsa and 3/8 triangle at the spinner end

3/8 balsa cross members and 3mm lite ply slat vents on the top and one slat vent as a scoop on the bottom.

Even if its not effective, it looks good...

(I think)

On this shot you can see the tiny gap down the junction between a 1/32 ply firewall face and the fuselage side... Now invisible as its been filled..

Its held in place by 2 wood screws - screwed in from the battery enclosure area

There is a battery access hatch completed as well. A nice fit but I have decided how to secure it, It has to be lifted off in one go, its too good a fit to lift the front then the back

The i.c. version cowl was much easier than expected. The OS35AX wrapped in clink film and screwed to the engine mount (reused). A chamfer needed on the fuselage edge to accommodate the silencer. This will be tidied with a small strip of 1/32 ply before the model is covered.

Same process for the E version, 3/8 balsa sides but a 1/16 ply back plate cut carefully so it can be slid out sideways. 3/8 balsa side and bottom and top.

and

A small strip of balsa linking the top and bottom around the cowl then carved and sanded to shape. The cowl has 2 small blocks of hardwood glued in top and bottom and this will have self tap screws through the hardwood into the nylon engine mount. The cowl slides of comfortably sideways. The needle valve or silencer or throttle linkage do not need to be touched to remove the cowl.. You can see the chamfer on the fuselage to clear the silencer. Different engines will need different clearances.

This is the gap on the E between spinner and spinner plate on the cowl.. Pleased with that, it doesn't bind..

[Martyn K]

While all this was going on, I got on with the wing for the KF3.

No plan needed, make up 4 spars with doublers, mark out the rib positions in pencil, pin the lower spar down against a straight edge, making sure its straight and glue the ribs into place, checking they are upright. The inner rib (W1) is a composite 1/4" balsa with 1/32 ply sides but not fitted yet.

The next 3 inner ribs are lite ply with the main spar slots cut to accommodate the spar and doubler. Use PVA or other slow setting wood glue and before the glue dries, fit the upper spar and LE and then gently weigh down the ribs so you know they are flat on the build tabs, use clamps to GENTLY pull the LE into the V. It needs to be straight, dont pull it out of shape.

The composite centre rib which has a precut slot in the balsa rib for a 6mm dowel

When the glue has dried, fit the upper and lower spars and allow to dry, Don't forget the short ribs that will house the ailerons. Check fit a servo leaving a 3mm gap at both sides.

The ailerons are assembled while still attached to the wing. I have used 3mm lite ply cap ribs for the ailerons. These are probably not really needed as the aileron will be fully sheeted but it does help keep a nice crisp edge.

These cap ribs are simply held into place with pegs - with a thin card spacer fitted.

The slots that limit the ailerons can be cut in advance or in situ. Personally, I prefer to cut in situ. Its very easy and ensure accuracy

The slots have already been cut in the two cap ribs for the aileron. Simply place the spar - in this case 1/8 x 1/4 balsa - where it needs to be and then mark the ribs with a scalpel. Cut each slot to fit and glue into place.

On the upper edge, I used 1/16 balsa spacers to keep it all nice and parallel

Both wing halves are at the same stage, hopefully I will get it (the wing) completed this week.

More to come..

Martyn

Edited By Martyn K on 13/11/2016 22:09:20

[kc]

It's looking good Martyn. Perhaps you should put the material list on here too ( Its on the MassBuild Chat thread) as I am sure lots of people will be keen to buiild one and will need to stock up with lots of 1/16th sheet.

On Friday you showed a pic of the noseleg fixings - I reckon that two u/c clamps are in tension and the middle one is not in compression as you state. It will pivot on the top (horizontal ) part when the noseleg get forced back when landing - in my view anyway. I might be wrong but bolting the middle one from the other side might be a worthwhile precaution.