Nick Somerville

I have had an enforced break from the workshop for some weeks but have been back on the build for a couple of days. Half the time has been spent re-hingeing the flaps. My painstakingly made hinges that I had epoxied into the flaps all had the hinge pivot points set too low; resulting in the lower leading edge snagging the t/e. The only option was to take a razor saw and cut them off and make a jig so I could drill through the studs and fit Robart type hinges. Annoying but if I had left them in it would have necessitated a wider non scale gap. Having cleared up that mess I used some thin aluminium sheet to simulate the hinges as seen from below. The gun hood has been hinged with a pair of Robard hinges and these, where the pivots extend above the deck, will be disguised within the front canopy frame at the scale position. Magnets have been used at the lower rear corner of the hood to keep it snug against the fuselage. A locking mechanism will be made utilising the protruding machine guns. The area at the front of the canopy needed some adjustment, so some balsa infill was added inside and then a some coarse sandpaper taped to a large can was used to achieve the correct form. This will be skinned with lithoplate extending further into the cockpit once I am ready to finalise the instrument placing. I am awaiting delivery of both a pilot and some cockpit parts that will allow progress in this area. I have also ‘flow coated’ the wing after a good rub back and when this is cured and thoroughly levelled I can start to add some detail to the wing. There is quite a bit to simulate so it should keep me busy for a while.

Thanks Jon for reply regards my rpm on the 180. Weather has been very kind this week so have managed 3 outings with the 180 engined P47 and have used half a gallon of the new Optimax fuel with plenty of needle tweaking. I fitted the Falcon 18 x 8, as the APC prop looks rubbish, and today registered 7980 rpm so pretty happy.

Can you explain the operation of the retracts and the mounting of them, Craig. Such seemingly small surface area and just one hole on each side of the mounts. Wings looking great btw.

Actually meant an 18 x 8

What rpm on the ground should I expect from my 180 turning a 18 x 6 APC wide? I have been doing some general maintenance on my P47 and ran the engine up in the garden yesterday. I recently got around to putting a battery in my tacho so was able to take a reading for once. I couldn’t achieve more than 6950rpm. TBH I haven’t really felt this particular engine has been giving its full potential, so interested to know what rpm others are getting. I have a new Falcon 18 X 6 that I shall fit and try today, perhaps that will improve things.

There is a brand new Laser 180 on BMFA today, which as mentioned is a perfect choice. I have one in mine but made a scale UC which mitigated the fuel tank position problem associated with the stock UC wire positioning. As much as I love Lasers, I do have a pumped OS 120 mk ll and it is a superb engine with a lot of power. Runs like a swiss watch. If you build light them it will be fine, albeit not the same unique sound as the Laser

I had some of the last white solartex when covering mine. 6m and Just a few tiny scraps left over when the covering was complete and the sheeted area of my fus was glass clothed not tex. so 8m should be about right for the whole airframe. It’s going to cost more to cover with Oratex than a new kit I shouldn’t wonder. The old fashion nylon and dope would be much cheaper.

With more changeable weather afoot I thought it wise to get the wing sealed. A careful final sand all over and then 48grm glass cloth wetted out with Easy Composites EL2 resin with the slow cure hardener. Gives plenty of time to work the resin in with a bit of scrap sponge and any excess softly scraped away with a potter’s rubber kidney. The kidney is the perfect tool for this as it is fairly soft and has no sharp corners. 65ml of mixed resin needed to wet out the underside and another 30-40ml will be applied on top for the flow coat. The 48grm cloth has a nice tight weave and uses no more resin than when using 28grm cloth. I purchase this off Ebay from a company called Sewglass Products at a very reasonable price. There is a lot of detail to add to the underside of the wing, particularly in the central area, but this can be applied on top of the cloth.

Regards the power for the retracts: I have Er40 Electron retracts in my P47 but power them with a separate battery in the wing connected to the sequencer. It’s a 8ooma 2s LIPO and lasts for ages (10+ sorties and several months between charges. Peace of mind knowing there is no possible drop in voltage/current to the rest of the model when deploying gear. A small 500ma would be more than adequate and hardly a weight concern.

3 pages to suck up and no chat about model making! For the model workshop I swear by my old Henry. I don’t bother with a bag and once the nylon cloth filter gets a coating of balsa dust it seems to do a better job of catching the fines, but still sucks like the proverbial. Most of the time it’s attached to a mdf shroud I made up for my Proxon disc sander.

I always enjoy installing radio gear, even if a bit fiddly at times. With such a short nose getting the main servos forward was a given, but I hadn’t fully appreciated just how the weight builds up. The throttle, elevator, tail retract steering and rudder servos on a removable tray tipped out at 250g, so glad it’s as far forward as possible. Having it removable allows access to fitting locknuts to the engine mounting bolts, the micro cooling door servos as well and the ignition unit. The pneumatic valve and operating servo has also been fitted. I would have put the tail steering wires on with the rudder servo, but once retracted The wheel has no room to twist. Having a separate servo means it can be set to disable on retraction. The little block between the throttle and elevator servo is a clamp for a Bowden cable that will run to under the gun hood and will be a manual control for the choke. Enough servos and channels already!

Love the way you give the engine a few strokes before firing it up, Ron. Sounds very nice. Lots of wire dangling about your starter. Popped my battery in a simple box and mounted it below the starter. Has a nice weighty feel when offering it up to the spinner.

Interesting model Bert. UC has some good features using readily available materials. Corona servos seem a but under soec for the size of a Precedent Stampe, but what has caught my eye is the amount of downthrust!!! Really! Also its a big looking engine and still lead up front. I had to add lead to the tail on mine.

Rather than keep worrying about my exhaust issues I have been sorting out a removeable part for the lower rear of the fuselage where the tailwheel retract sits. Some scraps of carbon square hollow stringers, a bit of G10 and some scraps of balsa came together nicely and the part fits with a pair of locating pins at the front and a hidden screw at the rear. This feature will allow servicing if the steering bellcrank, pull pull wires and the retract mounting bolts. Wheel up Wheel down A pair of inexpensive micro HV servos from The Component shop arrived today so the first of these have been mounted to operate the cooling doors. I shall put these on a Y-lead as I expect to be short of channels if not careful.

Also counting on the fan pushing plenty of cool air through the engine bay.

Thanks for thoughts Jon and for kind words re the build. The starter motor and carb protrusion's below the engine negate any hope of the muffler going underneath and in any case the angles of the in and out stubs also prevent it going there, even if I ditch the self start parts . I haven’t got around to the cowl fixing yet as have needed to finalise the exhaust installation first, then I will plan the position of the cowl fixings. I have the engine out again at the moment but in this photo you can see that the exit pipe has plenty of clearance from the fuel in pipes and also conveniently passes by the black plastic sleeves so shouldn’t heat the ingoing fuel at all. Although it appears to be to be touching the cylinder fins I can also ensure a 5mm gap there too. The pipes are heavy duty exhaust rated to 500c btw. I think my main concern was the overall length of the system, but then I suppose most of our cars have pretty long exhausts.

Firstly I am almost satisfied with the rear upper fuselage to fin shaping. Modified to follow a more accurate line than on the plan it’s nearly there. The full size has a surprisingly blunt lower part to the fin and this goes against my natural instinct to sharpen up the area, so I have had to be restrained. My replacement 16mm od flexible exhaust arrived promptly from Hoseworld.com. Around a tenner for a metre it will do the task and looks durable (rated up to 500C. So a mount has been made up for the muffler bracket, the Pitts style outlets cut back and there is just room to route tje exiting pipes between the engine and firewall and back around to the lower exhaust exits. Sadly my supplied flexible headers won’t quite reach the muffler in pipes but fortunately the flexible 20mm od exhaust pipe I wrongly ordered will not be in vain, as a short length will slip over both the muffler and headers. Quite a few jubilee clips to clamp it all up required but I am pretty confident it will work. Why not fit the muffler below, I hear someone say. Well there just isn’t room due to the starter motor and carb protrusions.

Sorted thanks Dave.

Some work on the fin access panel. It’s a scale feature but may also benefit at some point should i need to replace airlines or service the retract cylinder. To fabricate the scale piano type hinge I utilised 16 fishing trace ferules and a nice fitting carbon rod I had lying around. Lighter than brass and though fiddly satisfying to make. The door has a G10 backing and this sits in a G10 lining behind the aperture if 5mm width all round. This gave the ferules a good seat to cyano in place. The door has been drilled for the two scale position fixing screws.

The pipe I ordered from Toni Clarke arrived but the OD was 20mm and not 16mm 😫. Too big to bend around and achieve a satisfactory installation. 16mm is what I really need. Anyone have an opinion on this stuff I found on Ebay. It comes in varying sizes including 16mm. Slightly concerned that the operating max temperature is only 300 degrees C. https://www.ebay.co.uk/itm/362751491766?mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338703917&toolid=20006&var=632959133417&_trkparms=ispr%3D1&amdata=enc%3A1bbAuzn6ETpu97NN8dVvUoA37&customid=s%3AGS%3Bgc%3AEAIaIQobChMI06yHx8v4-QIVtIBQBh3cVQ-PEAQYBSABEgJ1-PD_BwE An alternative is this (more expensive but up to 500C) https://www.thehosemaster.co.uk/galvanised-steel-flexible-exhaust-hose?gclid=EAIaIQobChMImOG58s_4-QIVTbTtCh3wowxNEAQYASABEgI-xvD_BwE

Totally agree. Extraordinary level of detail. Very humbling.

Aah yes, see what you meant Bert. Without that stay my scale UC would collapse on even the lightest landings.

I got fed up with an embarrassing lack of directional control taxiing in anything above a light breeze. Soldered a tag to the wheel wire and ran an elastic band up to the rudder. Works great and should have sorted it earlier.

More gorgeous late summer weather. If I see a light wind day I always choose my Stampe for an outing, especially early in the day before the thermic breezes rock in. Thanks to Chris Montagu, our club. Chairman, for this lovely photo taken on just such a morning last Saturday.

Most of the fuselage has been sheeted. Still some work to do at the fin as the plan has a different outline than that of my Bentley drawings, so some careful measuring is required before I commit to finalising the shape. The rear fuselage has taken on a decent profile having reduced the bottom of the formers to give a more accurate and flatter profile. In an attempt to save weight I used 1/16th sheeting instead of the specified 3/32. I shall use the 1/16th for the area around and below the fin too and although this will create a step as it blends to the 3/32 It should encourage me to sand back the thicker sheeting at the rear. These are the headers and the Pitts style muffler that came with my engine. Lovely quality stainless steel pipe. Now I just don’t have room to fit the muffler below the engine so it’s going to have to sit above which gives a clean run from the engine exits to the muffler. The outlet stubbs on the muffler will be cut back and I have in the post a further metre of the same pipe ordered from the Toni Clark website. These will route back down to the lower scale outlets. I could simply route the headers straight to the exhaust but I am told the Valach has a bit of a bark without the muffler and I definitely do not want to be the noisy flier at our patch.