Super Flying Models. Fokker DVII kit

[Mike.K 60]

As said in my SE5a thread, I`ve got the hots on another build. This time it is the Fokker DVII kit, again from the same stable as the SE5a. That kit went together so nicely, I just had to get another from the same people...Ripmax.

Once again supplied by George Worley at 4-Max, I`ve raided the coffers once again and ordered the kit. The kit is £98.99, a PO-3547-700 motor £35.99 and next day postage £9.49. That`s a total of £144.47. I found in my Fathers bits box, an unused Detrum 40A ESC so that is suitable for this model. Had I needed one on this occasion from George, then a suitable one as previously fitted to the SE5a would have been a PP-TESC40AU unit at an additional cost of £28.95. George previously recommended the wooden JXF 12x6 at £5.90 each. As I write, George just phoned and said he was out of stock of the 700 motors but that an 800 was on the shelf and obviously would provide a bit more power, consume a little more Lipo capacity but I`d be able to throttle back a bit more. The prop would again be the 12x6. Its as broad as it is long so I agreed to the larger motor with no additional charge. A half hour later, I received a mail to say my consignment was on its way. Fantastic service I think you might agree with now a text from DPD saying the delivery would be by 11.00am tomorrow.

Mini metal gear servos have come from eBay. Five for just under £12. I suspect that these are coming from China although a Manchester source is in the listing. I found a 2.5m length of red covering on eBay from a Bournemouth source for just £11 delivered and I still have some white Oracover remaining in stock. That has cut the covering costs down to a very low level. Once again eBay has provided extension leads, Y-leads etc from a source in Wales. Previous experience with the seller has had the components with me by first class post the next day. So far, so good then.

Images here taken from the internet show a complete ARTF version of this DVII model. This is around twice the price of the basic self build kit which I have coming.

So the decks have been cleared, building board readied, knives sharpened and CA adhesive waiting to be used! The Ca I`m using comes from Toolstation in a 50gm lot. Just £2.32 a go for the Ever Build Stick2 product with a slowish 5-15 seconds bonding time. Their 5 minute epoxy is also good value and in my opinion rather better that the slightly more expensive Araldite product. It sets harder and faster and is much easier to sand, cut or machine than the equivalent Araldite.

I`ll also mention one of my favorite mini sanding and grinding tools. It takes a variety of 50mm type attachments ie self adhesive sanding discs, flappy wheel, etc. The tool is 240v AC powered but I do believe there is a model which is Ni-cad rechargable cordless available. My unit is shown in the images below and came from Axminster Tools for about £99. It is a cracking little tool and makes light work of roughing out balsa blocks, sanding down glass fibre or machining down crystalic gel coat on glass fibre components. Highly recommended. I`d be lost without mine.

More news on the DVII when it arrives tomorrow.

Mike

[Gerard 10]

Thanks for all the useful tips Mike.

😀

[Mike.K 60]

The DVII kit arrived just 22hrs after I placed the order with 4-Max. Great service as always.

This is NOT an ARTF type kit but one aimed at the modeller who enjoys building but without the hugely time consuming business of scratch building from plans. This type of kit cuts hours off building a fairly complex model at a very keen price and within a reasonable time scale. My SE5a from the sister SFM kit took just 120hrs from start to completion of covering and installation of radio and propulsion gear.

This kit is very similar to the SE5a with many identical construction details and cues being shared between the two models. Again it is excellent value and very nicely produced. I suspect it will build just a little easier than the SE which had two panels and a centre section to construct for each wing. The Fokker has no dihedral on either wing which means the makers have taken the opportunity to produce the main spars in one piece. On the basis of that, one has the advantage of essentially building two one piece wings rather than two wings from six sections as on the SE. Again the kit is well provided for in components. Wheels, carbon fibre wing struts, un-painted pilot this time, ABS engine and fuselage cowls, some good quality snakes as opposed the dowel and wire push rods found in the SE kit, decals,  nuts and  bolts, clevis ends, pre-bent landing gear and a special parts bag. Its very good value at £99 plus £9.49 carriage. Plans are clear and precise and the build manual appears to be a sharper production generally than that found in the SE kit. Typically, one amendment page is found at the start of the manual which clarifies any slightly confusing issues from the original print run.

I spent an hour or so popping out all the laser cut parts from the core ply sheeting which is of good quality and the laser burn was just right to make the parts fall out of the sheets with only minimal finger pressure. The break outs were clean and tidy and only require the odd bit of localised light cleaning up with a scalpel to be ready for use. Images now which give an idea of what I received and what I now have to nail together.

Although going slightly off topic, I was looking at the 4-Max site last night and I tripped over another kit that took my fancy as winter build. This time its for a Fokker Dr1 (Triplane) produced by Dancing Wings. I`d not noticed that model previously. This is another new one on the market and rather larger at 60" wingspan than the SFM SE or DVII kits that I`m presently involved with. The costs for this kit at £239.99 is rather higher than for the SFM SE or DVII but this larger model is in a class of its own and comes with about £60 worth of covering film included. George says in his advertisement that the kit is not one for beginners and I can see why. Complex it certainly is. Talking to George this morning, he describes the kit and being quite exquisite and of being something of a work of art. I`d envisage a build of around 300hrs, but what a build it would be. If I can get them to load here, you should find a link to the 4-Max site, the DR1 build manual and also to a Youtube video posted around a year ago by the manufacturers flying what is probably one of the proto-type models. It really is quite impressive and shows some very docile handling characteristics at very slow speeds. That model is on my list as the next project after this one! I`d better start feeding the piggy bank!!

DW Fokker Dr.1 (Kit and film) for just £239.99 from 4-Max

1.5M Balsa Fokker DR.I - YouTube

Comments and observations, please, Guys.

Mike

dw-fokker-dr1assembly-manual.pdf

[Mike.K 60]

Nine days on, eight of them building, sees this DVII now complete and ready to fly. About 90hours taken and no real issues. As predicted, the top ABS fuselage cowl was perhaps a slight headache. I`ll detail that before going further.

The removable top cowl is built on a chassis former with several perpendicular formers giving the top shape profile. On the SE5A, 2mm balsa sheet was damped and rolled around the shape, and held in place for half an hour to persuade the balsa to acquire the roll. Dried off with a hair dryer, it was then super-glued to the cowl former before being trimmed. It was finished with Oracover without any difficulty.

On the Fokker, an ABS cowl top is supplied to fit to the cowl chassis. The makers suggest UHU celulose/acetone based balsa cement as an adhesive. Believe me when I say that is hopeless. I gave up that fight as the ABS kept parting company with the chassis. A concerted clean up followed to remove the remains of the cement and generally abrade the gluing surfaces. Toolstation 4minute epoxy mixed in small batches and loads of small clamps were used to stablise the situation and provide a good, solid bond. That done, I had two choices for cosmetic finishing. Paint or Oracover or similar. I knew I`d have a fight getting a paint match so bit the bullet and gently covered the ABS with covering. It has been reasonably successful with a low temperature iron but a couple of wrinkles inevitably occurred. Nothing I can do about that but fortunately the worst examples of that issue are forward of the pilot and well disguised/camouflaged by the top wing. Its not my best effort but its good enough.

The SE5a is the more complex model to build due to a bigger bulk and more parts although the SE5 and the Fokker both fall into the 1200mm/48" category. The Se5a is 1:6.7 scale with the Fokker at 1:7.4.  Both are a delight to build and constructional progress really rockets along using Toolstation medium CA adhesive and the odd splodge of their 4 minute epoxy. Both adhesives come at an excellent price and do what it says on the label. I buy these glues in bulk and just gently plough my way through them. In the case of the CA, £2.32 buys a 50ml pot which is sufficient to build the Fokker without fear of running out. On the Fokker, the top wing was built ready for covering in an hour and  half. The lower wing was built in an hour, the landing gear wing in fifteen minutes and the fuselage in about three hours. The tail feathers took around an hour and a half also. Then its down to the details and covering which is what eats up the time.

I`ll mention that the SE5a was supplied with simple dustbin lid ABS wheel covers. They are easy enough to cover with Oracover and look the part once done. The Fokker is devoid of those covers which is a shame. I got around the issue by covering the centres of the wheels with Oracover and then shrinking. To my astonishment, the covering went perfectly and its almost impossible to foult the shrunk film across the wheel hubs. It certainly looks a lot more convincing than if I`d not addressed this issue and just left the wheels looking like something off a toy pram!

Whilst discussing coverings, both models require an absolute minimum of 3 two metre rolls of material. This allows more room for errors and ensures you have some left over for repairs. The Olive Drab and Cream Oracover for the SE5a set me back around £60. The Fokker took about three quarters of a roll of white taken from my stock and I managed to obtain a 2.5metre roll of red from an eBay source. That is a great looking material of undisclosed manufacture but has a white under-surface. That is not so good because using a temperature of more than 120 degrees C on the iron, lead to a white edge bleed which was frustrating. Thiis meant that any lp joints or edge seals showed badly. To get around this, I had to apply white on the trailing edges of the wings before covering the wings with red. A new scalpel blade allowed the covering to be cut and the bleeding white edge to blend unseen into the white trailing edge colour. All I can say was that the red material came for just £11 delivered and so in the case of the Fokker, dropped the covering costs down to a very acceptable £20.

I bought 5x9g Tower Pro servos from eBay delivered from China. This seemed a good idea at the time. Of the five units supplied only two are satisfactory. Three are defective and upon plugging into both my servo tester and the receiver, chatter as if having difficulty finding a centre point. Most disappointing and something I`ll be avoiding in the future. A classic case of buyer beware of cheapo units.

The SE5a weighs in at 5.1Lbs in flying trim. Lead ballast had to be added to achieve the correct CoG. The Fokker by comparison is a lightweight at 3.6Lbs and didn`t require any ballast at all. Not often that occurs! The motors....700Kva for the SE5a and 800Kva for the Fokker are identical in size, weight and dimensions. 40A ESC units are fitted in both models and they both share Overlander 4S 14.8V 2200mAh Lipo batteries. The SE5a is by far the more bulky of the two models and its heavier core air-frame weight accounts for the mass differences.

I modified the Fokker inter-plane struts. These were just 4mm ply which is hardly that good a material for units that will take tensile and compression loads. Out of the box, those struts were bowed and warped due to internal material stresses imparted releasing once the shape had been cut. I wasn`t happy with that so grabbed some 1/16" carbon rod and super-glue that to the ply. 1/16" balsa strips were added either side of the rods and a further strip of 1/16" balsa was added over the top of the carbon and the previously applied balsa. Images here show the detail. The struts are now straight and flat and have been profiled to reduce some of the added bulk. It was worth the effort as the increase in structural ridgity has been greatly improved for little weight penalty.

I also beefed up the cabane strut to the fuselage and wing fixing points. The maker suggests wood screws as fixings. Whilst these are likely to pull out in the event of a prang, I felt uneasy about their application in a load bearing situation. So fixings are now 2mm cap screw, washers and nuts, bolted right through mounting points. In the top wing, engine clench nuts have been added to the mounting points and similar bolting arrangements make for a rather more robust general arrangement. ....Avicraft now need to restock their box of 2mm bolts, washers and nuts...I snaffled Robs entire stock when I was over there the other day! The struts are hollow carbon fibe tube eith 2mm studs inserted using super-glue as adhesive. Once set, studs have to be screwed out of removal is required. The bond is excellent. The kit supplies a gauge to set up the struts to the required lengths. So you have the tube, a 2mm stud either end with plastic and metal ball and clevis fittings. These can pop apart in the event of impact. It is a good arrangement which makes cabane incidence rigging a doddle.

Images here show more of the build and the finished result. So another model is complete and ready to go. The conservatory is a shambles again and needs another clear up session. What now? I don`t like not having a project on the go. Raiding the bank yet again, I`ve ordered the 60" Dancing Wings Fokker Dr1 tri-plane kit from George at 4-max and it is due to arrive on Monday. The kit is not so cheap but it does come with 8 metres of covering. That`s worth about £80 if you had to source the coverings yourself from retail sources. The kit is as near as makes no difference, £240 plus £9.49 carriage. It is very easy to spend with this hobby!

So two nice models constructed within a very short time scale and with only minimal issues. I`d describe the DVII as the easier of the two kits to build. Both come, in my opinion, as "Highly Recommended" with 4-max as exceptional suppliers offering great advice and weekday next day delivery. George is always happy to chat and offer opinions when needed. He is certainly one of my "preferred suppliers".

I`ll bring both the SE5a and the DVII to the next meeting on 25th October 2018 . May be also the tr-plane kit although I will have started the build by then. I`ll construct a new thread on the build once the kit arrives.

Anyone wishing to build this kit is always welcome to give me a call for a chat if they wish. 07974 131127 anytime.

Mike Kennedy

[Pilot Ben 28]

Looking fantastic Mike!

Amazed to see the progress you've made.

It looks like the cowling job went well, although I think your model being electric does aid the covering on the cowl somewhat (no oil/heat)?

Look forward too seeing them all in the air!