Scale Soaring UK

Back in the 80s, John Hall (who makes the Pat Teakle Sailplanes range fuselages) used to market a number of fuselages/wing kits ranging from a 2metre ‘ish’ Prelude up to a 5m Albion.
As with the 100” Diamond electrified & fitted with 3m aileron & flapped wings last year, I have now designed a laser cut built-up wing for the Albion. John will be making the fuselages available again & Cliff Evans will include in his range as a short kit in due course
So... with building board recently made empty upon completion of the Salto, it’s on with the Albion

The wing was designed using DevWing & then the build drawings produced in devCad. The wing is designed in a similar polyhedral format as before, but now with ailerons, flaps plus an option for commercial top opening brakes to allow the builder to chose his weapons.
The wings are mounted using a 15mm flat steel joiner at centre height on the fuselage, which has large canopy & over-wing access hatches. The tailplane is a lowish mounted AMT type. The round nose section is nicely suited to motor installation & I am planning to use a Turnigy Gliderdrive encased Outrunner in this build (capable of 800w on 5S).
As there is a 4 part wing, the panels are <48” long, so easy to build indoors on my “office” desk top, rather than heating the workshop.

First up is the rudder, which is being built on a simple jig to prevent twist. The shot below shows internal ribs slotted into the false LE being built up onto the RH skin. Once the balsa horn area reinforcement has been added, the LH skin can be fitted prior to the TE and angled LE.

I’ve also started preparing the 1st Inner wing panel spar/web assemblies which will use 1/4” square spruce spars each side of the central web, top & bottom to form a true I-beam structure. One spar has been added to the bottom of the web so far & I’m about to add the one the other side before starting to slot the ribs into place.

Assembly of the spars is very quick, particularly if you use 48” lengths of spruce as this avoids the need to splice & there is very little to cut off.
As with most laser cut short kits, the wing structures go together very quickly, so one inner panel framework is nearly assembled & glued apart from the rear top spar, with the 2nd inner panel not far behind.
The shot below shows the most complete unit, viewed from the outer panel join.
The flap servo mounting plate is in place, but the brake servo plate has been omitted as electric brakes will be fitted in due course.
The flaps will be added later - fashioned from 2” wide balsa TE stock.

Sounds like my type of aeroplane Peter. I shall be watching with interest.
Brian.

Brian, you may remember Dave Charles flew an Albion in BARCS Opens back in the day. Was a very competitive model back then, with a good glide and able to move around the sky. Like you - looking forward to seeing this project develop.

Simon

Brian/Simon,
Can you remember which wing section Dave Charles etc. tended to use?

I’m currently using SD7037 on this build, but the flat sided fuselage around the root area makes it easy to accept any other section.
When I got the sample fuselage from John Hall, he said that he used to sell as a fuselage only - letting the builder add whatever wings they wanted.
I’m not sure that Pat Teakle made anything for the Albion, but may have made some ‘specials’

Meanwhile, the wing joiners have been installed in the 1st Inner panel, with the gaps between spars/joiner box/web filled with 3mm Liteply & epoxy to form a solid unit.
I removed the small rib sections within the joiner box slot (used to hold the rib together until installed) using a junior hacksaw blade, although a deep razor saw would also do the job, going in from the top on Rib1 & the bottom on Ribs2-4. The joiner tube has been left protruding as it will go through a further ply root rib to be fitted after sheeting.

The small cruciform tabs of the circular panel joiner slots were care full cut out with a scalpel & then the hole cleaned using a 6mm dia. rat tail file.

The rudder has now has both skins on plus top, bottom & TE strips fitted. These still need to be shaped & the LE added.

The first tailplane structure is being constructed, with top spar still to be fitted, plus joiner tubes, prior to fitting the top skin. 1” balsaTE will be fitted to the rear, plus curved balsa block tips to mirror the wing planform.

Simon, Aaaah, Yesssss. Well remembered young man! Well there is a blast from the past!

Peter, not sure what section Dave would have used, but SD 7037 is a reasonable choice. I used it myself on a couple of Eliminator 135 models that I built for my son and I to compete in RES thermal events. It is quite a lifty section but you can drive it around if you require to.
Brian

Yes I think the 7037 will be a good choice. I would have gone for an SD3021, but also with flaps - as you have flaps you can reflex a bit for penetration, and I’m not sure it’s too different to the 3021 then (it may be slightly thicker and/or more cambered). If you wanted a bit more speed the MH32 is a fantastic all-rounder.

Simon

Just looking back at Kai Erdmann’s ‘F3J Thermal Tips & Techniques’ book from the ‘90s (which also features a young Brian Sharp) to see if it it featured the Albion - It didn’t, but did feature Dave Charles later Albran, which used a modified Albion fuselage with T tail, and his own wings. He used Eppler E193 section for this. It was a large model at 4.9m span, but very pretty and featured early upturned wingtips.

Simon

Simon. A Young Brian Sharp! Really! A YOUNG BRIAN SHARP!! Was it in print or hand written by monks in a monastery? I think I need proof of that.
Brian.

I think we all need proof of that!

Ha, I was just looking at an Albion I have in the loft with "Pat Teakle" style wings (white foam with 1 inch by 1/4 inch spruce spars) glasscloth covered.
The wings are 2 piece - so a pain to transport and there was even a Futaba S148 servo still in the fuz on rudder.

I was wondering if it would make a half decent practice model for the Sport class of GPS Triangle racing as the weight was about 1.5 kg less than my moulded Valenta 5m Thermik XXXL and the same sort of wing area.
I have a spare Hacker B50 -7S with 6.7:1 gearbox, and plenty of suitable servos / Rx.

With a new set of Cliff's wings might be even lighter, what does the collective expertise think - good and cheap GPS entry/practice model or forget the idea?

John M

John - I think it would make a passable practice model for GPS triangle, but don’t go too light! Even though the older wing sections don’t look very different to today’s, there is no doubt the modern sections have better penetration whilst still showing a low sink rate. If the model is too light the danger would be a lack of mobility around the triangle.

Simon

And, as the gauntlet has been thrown down, some photos of Brian S, Dave Charle’s Albran 5T, and for good measure one of me in the same period, all from Kai Erdman’s book

Simon

Thanks for your comments on the Albion Simon.
So as I was planning on a new set of wings, get Cliff to cut the ribs to a modern section, then we are in with a shout of having something useable for GPS. Was always going to keep the ballasting option open.

John M

Wow Simon, that's a blast from the past. That O/D Buccaneer was one of my better models for F3b and cross country as well as breezy thermal days. I seem to remember it earned me a bit of silverware in it's time. I haven't a clue who the young guy holding it is.
However, whilst hunting through the archives I came across a picture of Dave holding what appears to be his Albion?
Brian.

I wonder if he made some short wings for windy days, but to be honest I don’t remember him flying that version. Must have been the era where we all had triple coloured wingtips with a gradual fade of colour...

Simon

Dave's pic was taken at the Brit Soaring Nats at Cranwell in 1987 and I think it was F3b day (hence the short wings). My Buccaneer pic was dated 1989, possibly when I was expressing my "inner feminine side".
Brian.

The Dave Charles pic looks like something of Multiplex origin to me, Fiesta or Flamingo maybe, but it certainly doesn't look like an Albion fuselage.
Wrong canopy opening and no second opening hatch between the wing roots, also wing root fairings which the Albion doesn't have.
Please correct me if I'm wrong though.

John M

Back to the build & the inner panels have now had their joiner rear incidence pins fitted and boxed in, plus hinge spar doubler fitted & everything on the top sanded to profile ready for the top skins.

The first 300mm electric airbrake assembly has been fitted in pretty easily as it just fits between the brake space ribs. It only needed a slot cut in the brake space root end rib (similar to that provided in the others) in order to allow clearance for the motor assembly, plus a couple of notches in the web/top rear spar to allow it to drop into place.
The brake assembly has been initially fixed in place with Evostick.

Meanwhile, the 1st tailplane has had its joiner tubes fitted and has been skinned in 1/16” Balsa. The 1/4” LE is being fitted as two 1/8” strips to allow it to follow the tip end curvature better. The 1” stock TE strip has also been fitted, so only the tip block is left to be added before the LE is profiled & final sanding.

Looking really nice Peter - please let us know the finished weights of the wing and tail panels once you have completed them.

Regards John M

Both inner panels now have top skins fitted.
First one now has servo hatch framing in place, cables threaded though pre-cut rib holes & ready for bottom skin which is currently being glued up ready to fit tomorrow morning.

With inner wing panels nearly skinned & ready to plug on, it was time to look at the fuselage side of the attachment.
The Albion fuselage has nice flat sides below the wing hatch, so no fuselage facings are required
First job was to mark the chord line - I decided to go 25mm below the hatch line & then position the root template in the centre of the hatch length. (Ignore the 2 moulded dimples on the fuselage side).
So.. marking through the root template, the joiner, incidence tube, wing retainer & servo connector access holes were marked on each side. Luckily, I had both 1/8” & 0.8mm ply wing facings on the laser cutting templates, so the thicker ones will now be used inside the fuselage as root reinforcement, with the joiner/incidence tubes blocked in between them. The thinner facings will be fitted to the finished wings.
Photo below shows joiner slot & incidence tube hole cut in fuselage & everything dry fitted to check alignment before attaching the fuselage reinforcement ribs with polyester resin in the workshop tomorrow.
There is no way that I would get away with the whiff of polyester resin in the house

At the front end, the fuselage nose was cut back in 2 steps whilst checking fit of the motor mount. The first cut was at 45mm back, then a further 5mm to leave a lip of approx. 5mm for mount fixing. (The fuselage will be cut back/squared off wrt the shaft line later in order to achieve a good fit with the planned 38mm spinner).
I also removed 5mm from each side of the forward hatch in order to be able to get the motor through. This will also ease battery installation
The mount will be fitted tomorrow using an initial front polyester resin fillet, followed by a rear fillet once motor (used for mount alignment) has been removed.

With fuselage joiner tubes in place, it was time to check the fit of the inner panels
(Length of stock TE taped on to give better impression of size, although 3/8” LE missing)

Meanwhile, a start has been made on the 1st outer panel.
Although the assembled laser cut parts come out at the correct length, the pic below shows the effect of a difference between laser machine & printer accuracies. The laser part are within 1mm over the 1.2m panel length but the print is just over 1% on the small side.
Although in olden days we just built to the printed plan, the laser cut parts notch together accurately, so the difference against the print is more obvious - particularly as I have a curved main spar & LE!
However, the answer is to find a straight reference line (False TE in my case) & use that to align the structure.

I this case, I spaced the (laser cut & notched) ply spar web off the building board by the rib building tab height (8mm) and jigged it into the correct shape to give a straight False TE spar.
The spar tip ends were steamed to follow the resultant web curvature whilst ensuring that the False TE stayed straight.
The pic below shows the assembly with the shorter forward spar being added, plus the tip section of the False TE doubler.

Nice progress so far!

Maybe obvious to the most, but it's a good tip to cut the nose of in two steps! I remember doing the same at once on my Albatros glider, even though I had a mold, the result was not perfect. Next time I'll take it step-by-step !

Daniel

Dead right.
Just cut the front off my Albion and spent a happy evening (4 hours) drilling and picking out the lead chips embedded in epoxy noseweight and trying not to damage the glass of the fuselage. It totalled 550 grammes of ballast giving plenty of scope for a powerful geared motor and esc.
Now need to remove the rudder to allow access to replace the bent aluminium elevator pushrod with a carbon set up for strength and reliability.
John M

1st outer panel structure was completed yesterday & the top balsa skin applied this morning.
I ended up fitting some temporary bracing riblets in the tip bays (with TE held straight) and now that the underside spars have been fitted the TE is still straight.
Photo shows the panel weighted down to ensure the rib building tabs, which include 5mm washout twist on this panel, stay seated on the building board.

I am expecting the top skin to lock everything in place, so will probably remove the temporary riblets before fitting the bottom skin.

Top skin now attached and a view of the underside complete with aileron servo cable and hinge hard points prior to fitting the lower skin later today.
I have tried fitting this panel onto the inner panel & happy to report that everything fits nicely

Once the fuselage nose had been trimmed back after fitting the motor mount, it became evident that the planned 38mm Aeronaut Coolnose spinner was going to be a touch small, so a 40mm was ordered from Stan Yeo.
This arrived today and fits nicely.

The first outer panel skin edges were tidied up today in parallel with advancing the 2nd outer panel build.
With the aileron servo connector just fitted on the 1st panel, I hope to be able to assemble the RH wing onto the fuselage tomorrow, albeit without LE, tip or control surfaces.

With the top skin fitted to the 2nd outer wing panel, it’s time for a quick assembly check, although flap, ailerons & wing tips still to be added

Now that I have the right wing more or less assembled, I can also do an initial wing weight check prior to covering.
Inner panel including flap, airbrake & flap servo: 720g
Outer panel including tip, aileron & servo: 435g
Panel joiner (8mm & 3mm Carbon rods): 30g

Thus, I reckon the overall wing assemblies (not including 100g for fuselage joiners) is 2.37Kg (5lbs 4oz).
Fuselage weight including motor, spinner, joiner tubes & hatch covers only is currently 950g (2lb 1.5oz).

John, not sure if my new wing is lighter than yours?
Peter

Peter, that is looking very good, might be tempted to dig my Albion fuz out, as for weights, I know its not the finished yet, but it is going to be a lot lighter than my Thermik XXL 5mtr electric glider, that flies very well with AUW of 6.7kg, so the Albion is going to be a floater, might have to put some ballast in
Chris

Thanks for the weights Peter much appreciated.

My old Albion Fuz is 933g (without powertrain) but that is with some bulkheads and stuff glued in.
Each wing is 1390g (lead in the light one to make then the same), with 1980's barn door brakes.
Tailplanes and two back to back 15mm deep steel blade joiners are 340g.
So with a powertrain (motor & esc) of 372g, a 4s 4500mAh LiPo battery 550g and 8 servos, Rx and GPS gear at say 350g the total looks around 5.3kg to 5.4kg. But there will be another 100g or so of repairs/strengthening to the wings and vac-bagging glass on the tailplanes to add.

Significantly lighter than my overweight & repaired 5m Thermik XXXL at 6.9kg and the wing loadings work out the Albion at 25% less than the Thermik.
Albion is about 10% greater area as well.

Question is - will it move round the GPS triangle as fast as the Thermik and will it signal & go up in lift better?
Decisions, decisions!
John M

Thanks John/Chris,
I probably could have sacrificed a little more weight, but tried to make the first build strong but light, as it’s usually easier to add weight than remove it
The full I-beam main spar assembly should be plenty strong enough & the wing design would allow a 2nd fuselage joiner to be added with minor changes if required.
I have used a Balsa LE & flap hinge spar doubler for lightness, but both could be uprated to spruce on the inner panel. The wings could also be glassed for additional stiffness if desired,
It will be interesting to see if the model can be balanced without the addition of nose weight due to the longish nose moment. The planned 5S battery should fit through the slightly widened forward hatch & fuselage behind the joiner.

Ballast could be fitted around the fuselage joiner, although no doubt tubes could easily be added to the wings immediately behind the joiner box. - the tube being bonded to the rear of the joiner area ply web.

Both wings are now completed with control surfaces hinged (although pin hinges not yet fixed into the wing) ready to apply a sealing coat to the balsa surfaces prior to covering.
Pics below show LH outer panel with aileron fitted & root end of RH inner panel it’s flap fitted.

I fitted five 1/8” diameter Robert pin hinges on each control surface & this job was greatly eased by making up one of the simple drill jigs recently shown by Brian Sharp on his MU28 rebuild. The jig allowed the fitting holes to be accurately & repeatedly drilled to achieve a straight hinge line which is just about in line with the wing upper surface.

Meanwhile, the MPX wing servo connector mating halves have been fixed in the fuselage. I fitted the connectors into Cliff Evan’s 3D printed holders (after removing the normal screw fixing ‘ears’) and then epoxied the holders into rectangular holes made through fuselage and internal 1/8” ply root reinforcement rib.

TE tailplane construction is also nearly complete with just the LE profiling outstanding prior to tidy-up & covering.

Attention now moves to fixing the AMT elevator & C/L rudder servos just forward of the rear incidence tube, plus installation of the AMT crank in the fin.

Decided to get the 2 hatch covers sorted today, so added small 1/16” ply spacers on the inside of each cover plus 1/16” ply tongues onto each spacer.
The position of spacers & length of tongues allows the front tongues to be engaged initially, then the hatch slid forward until the rear drops into place. Then slide the hatch back to engage the rear tongue.
The hatch is then retained, even if it moves back to the rear tongue spacer, which acts as a stop.
As it has to be slid forward to disengage the tongues, the hatch should only come off in flight if the tongues break off

Sorry, I missed your last but one post Peter. It looks as though the little drilling jig did its job. Your hinge lines look nice and neat. I think my tubes are a little lower in the jig as my hinge knuckles are not quite so prominant.
Brian.

B Sharp wrote: ↑14 Dec 2020, 17:03 I think my tubes are a little lower in the jig as my hinge knuckles are not quite so prominant.
Brian.

Perhaps I should remove the strip of 1/16” ply I added on the inside upper face of the jig then!
That would drop the hinge line a little

Latest tasks were to fit a small servo plate between ply fuselage root rib doublers just forward of the rear incidence tube, positioned in height so that the servo horns are just above the incidence tube.

The 3D printed AMT crank is mounted in the fin with the pivot at the points marked by moulded dimples on the fuselage.
The crank is fitted with a 5mm OD bearing tube to rotate nicely on a 4mm OD tube through the fin. The tailplane halves mount onto 3mm rods passing through the pivot tube and crank rear hole. The crank is designed to fit in the fin when running in 1/16” ply spacers fitted on each side. The spacers are fixed to the inside of the fin to provide additional gluing area for the 4mm tube, whilst trying to ensure that the pivot remains free after the resin has cured.

The elevator pushrod was made from 6mm/3mm carbon tube & fitted with short threaded rods each end to fit metal clevises.
Once everything is installed, the pushrod clears both incidence tube and rear fuselage so a pleasing result.
Just need to check that the rudder C/L wires will clear everything now
The fin post has been cut from 3/8” Balsa, so this will be fitted once the C/L wire exits have been cut.

Having decided to fit pin hinges in the rudder, the LE has been rounded off & the C/L horn fitted.
So, with pin hinges installed & dry fitted to the fin post, an overall fit can be checked before the fin post is fixed in place using polyester resin.

Apart from fitting the wing Unilocs, this more or less completes the structure prior to covering.

I bought an Albion fuselage a couple of years ago, and I've been working on it from time to time. The model you discuss above doesn't seem to be quite the same as the one described in the documents that came with my fus, and I wondered why there are differences. My fuselage looks the same as the one pictured above, except I hadn't thought of the sides as particularly 'flat'. The documents I've got appear to be Neil Sleight's plans for an XC1 (never built) and an XC2 version, a set of notes about some of the feats he achieved with the XC2 - including US style cross-country events in California (for which the model was designed), the BARCS out and back annual slope record, 3rd place in a Belgian International F3J event. etc. There are also two photographs of Sleight with his plane in California.
The plans show a 3.8m RES model. I wanted something a bit bigger and with ailerons. So far, I've built a rudder and a post. I've also built a gravity feed foam cutting machine, learned a bit about using it, and cut four usable foam tailplane cores which are awaiting vacuum bagging. I've also had some foam inner panels cut. I shall probably make two sets of tips, one from foam cut by me (now I know how) for a 4.2m version and the other built up for a 5m version.
I decided to go for Drela sections. The inner panels are A4/A3. The tailplane is HT14/HT12. Who knows what the rudder is?
I'm building this to go for walks with, so I'm not too fussed about performance in competition.

John,
I suspect that your Albion fuselage/plan may be another model, coincidentally having the same name.
I am pretty sure the the John Hall one this thread is based on was always intended to have 5m ish wings.
However, I’m checking with John, so hope to be able to confirm whether he knows of a Neil Sleight version.
Peter

John,
From John Halls’ recollections, it might just be that your fuselage is one of the original 1980’s ‘ish’ vintage that travelled to the U.S for competitions & stayed there/spawned a plan from Neil Sleight.

John says that he used to have a photo of about half a dozen Albion variants in California, with Robin Sleight, Rod Potts and Dave Charles among others whose names he cannot recall. They were there as a team and John believes they sold on the spare fuselages rather than ship them back to the U.K. John never saw any of the variant designs but the Albions primary purpose, at the time, was to facilitate “own design” models.

I attach an overhead shot of my fuselage showing how near parallel & flat the fuselage sides are in the rear hatch area. The fuselage there is certainly flat enough to seat the wing root ribs directly against the fuselage surface without a gap.

It's definitely a John Hall one. It says so on the plan, and looks very similar to yours. It might be that we just have a different concept of 'flat'! The unusual hatch over the wing seat is a clear pointer, as is the quite sharply raked rudder LE.
I've just noticed that somehow I wrote Neil where I should have written Robin. Sorry for confusing the matter.
I'll take some photos and post them later.

Photos as promised. 1. This is how the plan for XC1 is described, XC2 is similar in shape, but different in detail and is claimed by Robin Sleight as his own design. They are both the same span, 4.14m (not 3.8 as I claimed earlier) 2. Here's the fuselage .
3. I put the rule on a couple of pieces of ballast so that it touches the fuselage side roughly where the centre of root chord will be. As you can see, there's about 2mm of daylight at the LE and another 2mm at the TE. 4. Here's the curve of the fus viewed from the front. 5. The last two are the photos of Robin Sleight with the XC2 that I found in the fus when I bought it. The photo of the launch has a caption and a note on the back:
CALIFORNIA VALLEY, CALIFORNIA, MAY 1988 - PRIOR TO 18 MILE FLIGHT. (ROBIN ON LEFT)
Peter - no need to return anything to me - these are all copies for you to keep and pass to your friend. Robin I believe the '18 mile flight' was a world record at the time.

Sorry about the formatting in the last message. I tried to fix it, but failed.

John,
You have not got an Albion fuselage.
It’s probably a Rubicon which is very similar but has a wing seat to bolt a wing down onto rather than a mid height wing which my fuselage is designed for (there are even dimples in the sides of my fuselage for the original wing section joiner rod centres).
See pic below (ignore the spare forward hatch cover taped to rear of fuselage). The rear hatch cover is white, just behind the forward one. The fuselage moulding under the rear hatch comes right up to the bottom of the hatch, just like the front one.

The Rubicon rear hatch goes over the wing.
Look at my thread photos again & you will see what I mean.
John Hall may well be along later to confirm the above.

Your picture formatting issue is probably because you ‘inlined’ the photos. If you omit that feature & add a title to the photos instead, it may be more like what you wanted.
Peter

Thanks, Peter,
You know, I've been puzzled by the wing seat ever since I first looked at it because it seemed more suited to a bolt-on one-piece centre section than for a central joiner. It was only after I looked again at the photo of Robin Sleight that I started to have doubts. Then your remark about the fuselage sides being flat really rang bells. It doesn't matter much to me because I just want a model to take on walks along long slopes. Whether it is called Albion Redux, or Rubicon Redux doesn't make much difference. Everything other than the fus will have been designed and built by me.
I'd like to hear from John Hall, though!
Thanks for your help.

John
What you have is a Rubicon fuselage and I can confirm what Pete has said so far.
If I can find it I will post a picture from the same California event showing the team holding their Albions, Robin Sleight, Dave Charles and Rod Potts among them.
History.....I got to know Rod and Robin in the late 70's at Cross country comps at Crook Peak. At that time Clive Hall (Dad) was making Algebra 8 fuselages for Sean Bannister but was not keeping up with demand and it was Rods suggestion that I takeover production. Thereafter Rod would carry stock round the competition circuit selling on my behalf.
It was Rods suggestion to create a fuselage for a large span model and he contributed the name "Albion". I carved the pattern from a big chunk of Jelutong and finished it with Furan resin (horribly laborious and dated technique) It has flat sides for a plug on wing, there are two faint countersink marks each side, these are purely a datum and not as suggested join rod centres. The concept was for what we called a "component fuselage" on which people could base their own design.
With the arrival of F3J the Albion was deemed a bit big, hence the Rubicon. It was created by whittling away at the old Albion pattern and was changed to a bolt down centre section to help cope with aggressive launch techniques. The rear or wing root hatch cover is moulded down to the wing seat allowing for trimming to fit any aerofoil section. (if you are missing this cover let me have you details and I'll post one)
Hope this helps Cheres John

Great to hear from you, John!
Mysteries all dissipated, except perhaps the mystery of why there were details of one plane stuffed inside a different (well, not very different) one. Fortunately, my plans for the rest of the model are not affected much by the reidentification. When I started thinking what to do with it, I was thinking of a three-piece wing, so I can safely go back to that idea, which makes the structure a lot simpler.
I've been calling this project 'Albion Redux', but since I seem to be fulfilling your original conception by designing my own flying surfaces, perhaps I should just call it a Rubicon, even though my proposed versions will be no smaller than Albions.
Thanks for the offer of hatches, which is not necessary. The central hatch I've got matches the fus in colour, but of the two forward hatches that came with it, one is sky blue and the other orange - another mystery!
And finally, yes, I'd like to see the photos, even though they are of a different plane. I'd even like to see pictures of Rubicons, if you've got any.

All the best
John

Well, back to the Albion there has been a bit of movement on the covering front.

Rudder covered in red/white check & hinged to the fin post ready for this to be bonded into the fin tomorrow.
Meanwhile, the tailplane halves have been treated to the check pattern on the undersides & plain white on the tops.

Profilm ordered from Stan Yeo, so hopefully should be able to get the wings covered in a few days time.

With covering now complete and flight battery available, I’ve just done another quick assembly to check balance & impact on overall weight.
Even with a 5000mAH 5S LiPo (which just fits alongside the 60A ESC) I’m going to have to add roughly 570g immediately behind the motor to achieve rough fingertip balance at 93mm behind the root LE.
This should be a conservative starting point (33% root chord) given that the tip panels have a rearwards curving LE which should move the MAC aft a bit.

With that amount of ballast & the flight battery, the overall weight comes out at 5.2Kg (11.5lbs).
If we can get the expected 800W or so out of the motor, then the climb should be adequate.

Unfortunately, I forgot to take a photo of the assembled model, but previous pics of the bare model & covered tailplane should give you the idea.

After fixing the previously identified nose weight into position using Silicone sealant (as 2 blocks located on each side of the fuselage, just behind the motor, leaving sufficient room to attach the motor connectors) I have just re-assembled to check balance & take a final pre-flight photo.

The 60A YEP ESC fits on the floor just behind the motor & slides underneath the weights. The 5S flight battery fits in the forward canopy opening behind the ESC with room for the XT90 connector down the side. A separate BEC will be used & will fit between the ESC & battery.
The Rx fits behind the battery.

The undersides of the tailplane, control surfaces & tip panel ends are red/white check.
Cliff will probably add some trim stripes to the basic covering at some point.
The weight & CoG are displayed on my DIY CoG meter.

That looks quite the business sitting there Peter. Well done and good luck with the maidens.
Brian

Well done Peter - looks really good and pretty light for a 5m glider.
You've motivated me to get mine refurbished, just need to work out how to chop the 2.5m wing halves into two and add joiners / strength for a more easily managed and transportable 4 piece wing. Noting your dead weight for CG balance as well, I think a refit of the servo positions and GPS gear to move it all forwards will help too.

John M

Peter,
Any chance of details of the weight and balance device??

BC

Barry,
A quick overview below, but if there is interest then I can provide detailed schematic & firmware in a dedicated thread in a more appropriate section.
Essentially the device measures the weight sensed at two points on the wing chord using standard beam load cells.
With a little bit of maths, these two weights & their locations behind the wing LE can be used to calculate both overall weight & location of the mean weight location between the two measurement points/location wrt the wing LE reference.

The load cells each contain 2 strain gauges whose resistance changes dependent upon deflection of the metal bar they are mounted on. The strain gauges are connected as a Wheatstonebridge (think full wave rectifier with resistors instead of diodes) & the small voltage changes as a result of weight applied to deflect the beams are amplified & converted to a digital value in small off the shelf HX711 modules.
A small Arduino processor module then calculates the display values and drives a serial data 16x2 LCD display

I think that I use 10Kg load cells, but will need to check that out.
The setup is easily adaptable to different uses by using different capacity load cells.
My mechanical arrangement is just one way of doing it, but never got around to tidying up the lash up.
My processor board has a voltage regulator, so I can operate from a 2 cell LiPo or equivalent.

Peter, Thanks for that. More detail would be good, when you have time.



BC

Great work with the Albion & CG/Scales Peter.

For others, if you want don’t want to build a CG/Scale, there is this (max 4Kg) (and others available on-line, capable of higher weights): https://www.hyperflight.co.uk/products. ... ring-scale (I have no connection with Hyperflight)

Simon

Simon,
That maybe where I started from, or one like it.

I have found my design file, so will make up a connection diagram & start a new thread in the Equipment section some time over the next few days.
A note here is that in order to build this sort of unit, you need to be able to program the firmware into the Arduino board (needs the Arduino IDE installed on a PC and a USB cable) Unfortunately, it’s not just a matter of getting a pre-programmed Arduino device as the individual load cells need to be calibrated (by running an initial calibration program in the hardware) & the appropriate values inserted into the program before this is uploaded to the Arduino board. It’s not difficult, but a necessary step.
However, you can make a unit capable of handling larger weights if required - simply by using higher rated load cells.

As a taster, here is a link to a uTube video describing a strain gauge based set of weighing scales:
https://youtu.be/sxzoAGf1kOo

The HK canned Outrunner motor & lack of cooling air exhaust proved too much for the ESC on a very hot day earlier in the year & the ESC gave up the ghost, causing Cliff to land quickly with a smoke trail!
Luckily, the battery is ok & the forward fuselage escaped with only minor charring!!
The motor may be ok, but have not risked putting power on it yet.

So …. a re-motoring job was taken on, together with making provision for air exhaust via the forward canopy.
It was decided to use an Airtek 4250/600 outrunner & equip this with a long shaft to enable it to be mounted further back due to its larger diameter. The long shaft is supported by a front bearing mounted in the nose former.
Cliff printed a couple of carbon loaded filament formers & the scheme allows the motor to be inserted/removed.
The pics below show story.


As there is now a 40mm+ gap in front of the motor, a nose ballast cylinder can be fixed up front. This has been cast in a simple plaster mould (made using a very lightweight 3D printed plug) & the result is shown below, together with a T shaped jig which allows the ballast cylinder to be held in position against the front former whilst being fixed using polyester resin, applied from the rear.


The nose ballast weighs 200g & equates to nearly half that previously needed behind the original motor. Hopefully, this should now be most of what is needed to balance the model.
The plan is to cut a NACA profile outlet in the front canopy.
Cooling air is taken in via an Aeronaut cool nose spinner.

I’ve now added a NACA shaped vent to the forward canopy after 3D printing an angled shroud and glueing this to the inside as shown below.
The rectangular vent opening is approximately 25mm x 5mm which is more than 3x the cool nose spinner inlet area.


Now just need to tidy up & paint the shroud ramp red.

Front hatch looks a lot better after the vent has been treated to a coat of red humbrol enamel

Has your Albion flown yet?

I am having a loft clear out and have a 5M Albion fuselage which unused and needs a new home. Complete with both hatch covers.

Richard

John Treble wrote: ↑18 Jan 2022, 13:32 Has your Albion flown yet?

Yes John, it has, the only problem I had was the speed controller packed up. Other than that, she flies very nicely.

Some shorts of take off and landing.

Nice ones Cliff