Jump to content

Nick Somerville

Members
  • Posts

    908
  • Joined

  • Last visited

  • Days Won

    7

Nick Somerville last won the day on June 17 2023

Nick Somerville had the most liked content!

3 Followers

Recent Profile Visitors

2,730 profile views

Nick Somerville's Achievements

636

Reputation

  1. Belly pan sheeted and hot air duct fabricated. The rear screw is temporary to pull it away from the magnets. They are quite strong, though there will be a hidden catch to stop it dropping off when landing heavily (not uncommon for me). The forward portion of the duct has a hinged cover yet to be made. Looking down the duct. The hot air duct from the inside. So that’s it for the balsa bashing on my Hellcat. Summer has finally arrived here so its flying time for my other models!
  2. Wings and fuselage now glassed. Still needs a good rub back and a second coat of resin but have found that this is best done several days after the initial application, so the resin is fully cured. 45grm cloth (sourced cheaply from ebay) and Easy Composites resin. As it continues to rain and blow in these parts I am pressing on with the last of building for my Hellcat. As I have constructed a two piece wing the belly pan needs to be removable; a benefit being it will hide the wing fixing bolts. The formers have been temporarily double sided taped to the wing and at the rear two pairs of neodymium magnets set on the wings and rear former will hold the pan in place. The front former has a rectangular aperture, matching the hot air exit duct from the cowl. A further duct inside the belly pan when added will exit at the oil cooler flap.
  3. Thanks for the heads up on pricing Ron. Got my order in for 5 gallons which should keep me sweet for a while.
  4. After measuring dozens of times to ensure correct alignment the front locating dowels have been fitted along with the rear hold down bolts. With that milestone completed I just had to pop the retracts in place and get her on her wheels for some photos.
  5. Thanks Ron. Can’t take credit for the design. Fine scale modellers Simon Lawson and Steve Rickett both demonstrated this method on their Bates and Zirolli Hellcat builds. It does work well and is so much neater than the four screws employed on the servo hatch covers on my other models.
  6. Wings now almost completed ready for glassing. Inboard flaps fabricated, LE and tips added and shaped. Just need to make the final fettling for the wing to fuselage mating and addition of locating dowels and securing bolts. the six servo hatches were cut out with a fresh blade, skinned with 0.6mm G10 for durability and lightly sanded on the inner surface for a flush fit. A neodymium magnet and tongue holds them firmly in place. A piece of thin wire is inserted into a tiny hole for removal. Hopefully barely noticeable after painting.
  7. The first set of covers had to be binned as I had made the blister mould forms actual size and by the time the carbon cloth had formed around them, they ended up about 3mm too big all round. Also there was some lifting from the flatter wing surface parts during curing. I re sanded the balsa forms until they were 2-3mm smaller all round and after laying up the cloth as before I covered with a further layer of ‘Peel Ply’ and then weighted everything down with freezer bags filled with sand. The trimmed parts are strong but have sufficient flex to absorb knocks and weigh just 25grms each. Pretty pleased with the result that conform to the wing profile perfectly.
  8. Hello Mike I will try to outline the key costs, but bear in mind the choice of engine and radio gear has a huge impact. In my case the Saito FG90 is twice the cost of say a Zenoa 80gt twin. Plans, laser cut parts and additional wood for the Hellcat was about £500-£600. Retracts and wheels plus pneumatic components £700. Glue, paint, resin other parts £150. So realistically it’s around £1500 without the radio and engine. It’s likely to be a 20 month project so £75 a month for the airframe. I consider it great value as I enjoy all the hours of building. My previous build (Vailly 1/4.5 FW190) was cheaper as I bought plans, wood and retracts from someone who had decided not to build the model. Also my next build will be a 1/5 Bates Bearcat, for which I have bought everything needed at half price; again from someone who decided not to build it. So if you are put off by the cost but really want to have a go at a large model, there are some great bargains to look out for. Regards staying power: my advice is only ever build one model at a time and always finish it. I always have maintenance and repairs to carry out to keep my other models airworthy in any case and have a small workshop too.
  9. With the lower wing skinned I haveshaped up a pair of leg cover blisters from some 1/2” soft balsa. In this photo one has been covered in heat shrink fabric (don’t have any film). The leg area of the wing had some waxed paper taped over and the blister double sided taped in position. With the whole area lightly smeared with some car wax 2 layers of carbon cloth and a layer of 48grm glass cloth were layered over and wetted out with Easy Composites resin. A vacuum bag would have really helped keep everything flat and compacted but as I don’t have this equipment it was a matter of keep checking as it cured and some pins where there was some lifting.
  10. . Looks like fashioning shapes from it will be a trial though. Hello Nigel, nice to following from New Zealand. As mentioned in my build notes, I have found for small parts multiple holes with a fine drill on a dremel works for me. I was visiting a clubmate the other day and he uses a fine blade in a small bandsaw works for himself. Carbon plate too up to 4mm thick
  11. Finally buttoned up the lower skins on the wings. A section of outer skins nearly ready for gluing with cut outs for aileron hinges, aileron servo and outer flap servo access. My once seemingly endless stash of 1/8 4” sheeting has all but gone, with just enough left for the belly pan. looking forward to adding wing tips and leading edges. With the wing halves pushed together onto the joiner tube this is the first trial fit in preparation for fitting the front locating dowels amd rear retaining bolts. So far looking ok with not to much work needed around the saddle. One the fixings have been set I can make up the inner flaps and then the final structural component, the belly pan. Also with the lower skins done I cam lay up the leg / wheel covers.
  12. It’s always a relief to finalise hingeing and actuating linkages for flying surfaces, especially when it is all hidden. I can only hope the flaps and ailerons work out as well as these tail surfaces have. I have installed a carbon pushrod to the elevator and closed loop to the rudder. Nice and smooth/slop free with everything lined up as it should. The elevator and rudder trim tabs have been fabricated from G10 with carved chemiwood dummy actuators. The patchy grey areas are where I have primed inside the shrouds as they won’t be easy to get to later. On previous models I painted the elevators and rudder separately and then fitted them. However for this model they had to be installed first. When shaping the forward fillet for the fin I found I had an unwanted hollow at the forward part and had to resort to a skim of lightweight filler to blend things in. A final shaping of the rear spine and a good sand all over and the fuselage will just about be ready for glassing. I haven’t decided though whether to cut the rear windows before or after glassing.
  13. Majestic as ever, like all your models Chris. Still using the HQ wing section I see. Look forward to seeing it at the patch when the weather improves.
  14. With weather awful I have spent the weekend spending far too much time fiddling with the cowl flaps. My intention had been to have them servo operated but in the end have accepted that the geometry for my plan was likely to result in some strain on the servo when either fully opening or closing the flaps, depending on the system employed. Ultimately I decided to have springs (bits of old fretsaw blades) keeping them open and a thin wire limiting the amount that they open. The pressure to close them is such that I am hoping that the prop wash and speed of the model at full chat should mostly close them, but at slower speeds the springs should hold them open. Hinges are reclaimed from a deceased model. I also added dummy exhaust stubs at the four ports.
  15. More work on the cowl. To my horror when mounting the engine for the first time I found that my ‘careful’ calculations where some way off and the engine was sitting 12mm too high. In my defence the plans for the engine box area just don’t match some of the parts and to an extent I have had to wing it a bit in this crucial area. Additionally the prop hub was 3mm behind the cowl lip. In the event 12mm was so much better than a few mm as I was able to drill new holes and add new captive nuts behind the firewall avoiding the originals. A 3mm G10 plate was added and new apertures cut for the fuel line and carb. The four parts for the cowl edge to slip over and place have been glued and screwed against F1, each with a pair of magnets imbedded. Their twin counterparts will be glued to the cowl. I am hopefully that the combined strength of 16 10mm neodymium magnets will hold the cowl in place without the need for any bolts. We shall see! An additional benefit of the G10 is the spreading of load where the 40mm stand off’s press against the firewall. You can see here the carb almost flush to the plate and the Venturi is well inside the fuselage. Once the engine is permanently mounted I shall seal around the sides of the Venturi with foam rubber so it can only draw cool air from inside the fuselage. Engine temporarily mounted. I took a front view of the engine from the Saito website and printed it out actual size. This was cut out and traced onto light ply and fretted out for the baffle plate. The clearance is between 1-2mm around the engine but until it is glued to the cowl I won’t be able to make any final adjustments. I should think 2mm will be ideal all around to keep the airflow close to the fins but not so close I start a fire. Here with the cowl in place. Note the lower cowl cheek still to be added and the air passage opened.
×
×
  • Create New...