Jump to content

John Rickett 102

Members
  • Posts

    233
  • Joined

  • Last visited

  • Days Won

    10

Everything posted by John Rickett 102

  1. I think that's the way Ron, an old fashioned letter is more likely to get attention than an email - whether there's a reply is another matter!
  2. I've written a letter to AGC Sales asking for the rectification plan. In the first instance, I'd suggest each owner does the same. The contact address is on the Laser Engines website which is still active.
  3. Thanks Ron and Martin. Yes that's where I read about the inline engines - I must try to stop speed reading when searching!
  4. Thanks Ron, I read in one of the earlier posts from Jon that product support was being limited to the 200i and wondered what that meant, that post seemed to have disappeared. Hopefully when the dust has settled the situation will become clearer.
  5. Ron, I got a 200i for a project which I've had for about a year but still unrun. Can you please advise what the fault is and is it in all of them?
  6. Steve, That's good news. A quart is a quarter of a US gallon = 946ml, so near enough to a litre when estimating how much you'll need. I would strongly suggest getting fabric cement and its reducer (thinner) from the supplier if they have it, its purpose made for the job so will make the task of adhering the covering so much easier. Ask if there is an instruction sheet for the fabric cement - to tell you how much thinning is required for initial application and then adhering the covering. The instructions are unlikely to be on the can, so best to know the start points for thinning before lashing on the stuff! If stored correctly, dope will not deteriorate in the can over many years. Fabric cement, or at least the stuff I use, will discolour in the can over time but is still useable.
  7. Satisfied that the cabin interior parts would go through a doorway with sufficient margin, attention was paid to making the doors. With multiple curves, the challenge was how to make them to hold the correct shape, yet be light and strong. I first considered making a mould and laying them up in fibreglass, removing all but the frame afterwards. I’m sure this could have worked but I wanted a way of building in a rebate for the glazing. There may be other suitable methods but I settled on making them out of laminates of ply having first proven that the ply would bend sufficiently and then hold its shape and that the corners could be made strong. The frames couldn’t be more than ¼” wide otherwise the result would look clumsy. A couple of test pieces were made up as in the pictures 0.9mm ply once wetted and allowed to soak for 10 minutes then laid up in 3 strips over a suitable former, will hold its shape. By overlapping alternate corners, the strength is as high as it needs to be. No attempt has been made to force the joint to destruction, but in pulling at it as if it were a wishbone, satisfied me that this type of joint is more than adequate. The doorway former was made form scrap bits, covered in parcel tape or Sellotape and clamped into position. Each side has a curve to some degree. It was then a case of adding the ply strips and slowly building up the layers. There are 6 pieces to each layer with 6 layers required to get to the desired thickness. With each strip being wetted the drying time takes longer so is quite a slow process...but we're getting there.
  8. Steve, As you're using Koverall, which is heat shrinkable, you do not need to use a shrinking dope. A shrinking dope will carry on shrinking long after its dried - possibly for months, albeit at a much reduced rate, however it can cause warps to materialise which weren't there when first covered. Non-shrinking dope will still cause the fabric to shrink but not by very much. Having already tautened the fabric with heat, the dope is there to fill the weave and make the fabric air-proof. Koverall has quite a loose weave compared to other polyesters so may need a few coats of thinned dope to completely fill the weave, The thinning doesn't reduce the effectiveness of the dope, only the viscosity. Your model is quite large and you're going to need more than normal modelling size cans, I'd say at least 1 litre of dope. I suggest you contact one of the full size restoration companies in NZ, of which there are a few, and ask where they get their supplies from. You could also ask where they source fabric cement from, this is purpose made for the job of covering.
  9. Steve, its easy to detach a shroud from a plug. There is a small plastic tab holding the shroud onto the plug, a flat blade screwdriver inserted at the back will lift the shroud from the plug. The tab is only on one side which will be at the top if you lay the cable as in the picture. It will snap back on afterwards.
  10. While having to wait for decent painting weather for two other projects, I thought it therapeutic to progress the cabin interior. With Beryl looking a bit more life-like with some colour in her cheeks and with a new completed control column to grasp and straps to keep her in position, it was time to prove that she and the tanks could all be fitted through the doorway. Major surgery was required on her feet (her ankles had to be removed) to clear the obstruction of the radio tray, even so as the butchery is low down below the instrument panel, I don't think it will be very visible. Beryl didn't say a word. I doubt a four-point harness would have been fitted originally but to my mind its in keeping with a perilous record attempt and its all that holds her in the seat.
  11. With there being no damage to the exhaust headers and as the whole model is firmly in the ‘sport’ category, the headers were used again in a similar position as before. The exhausts should exit the cylinder heads (if there were any) but these were just put as low down on the rockers as possible. Having only used a few layers of glass cloth, the walls of the rocker covers came out at 0.5mm thick which provides little support for the exhaust stubs. Small pieces of 1/8” ply were added to support the joints, I thought this prudent as its likely the exhausts could be used as handles when removing the cowl, so didn’t want too much flexing and eventual breaking of the fibreglass bits. All the main components have been completed now so it’s a waiting game for the weather to improve to get on with painting.
  12. The second cover was released from the mould after 18 hours. I'm pleased to say it came away easily which I think shows that the initial coats of wax are still working and so less coats are required for subsequent lay-ups. One unexpected benefit of using 25gm cloth as the base layer was how smooth the surface is. I'd used the fine cloth to ensure that the fairly tight curves were followed without using gelcoat, which I don't seem to be able to master (I'm sure its me as others have success) however, the surface is much smoother than starting out with 50gm cloth, which is what I've done previously when making something with gentle curves like a cowl. I suppose this is an obvious discovery now though its something to remember for future lay-ups. A plus for using fibreglass for this task instead of getting another set of ABS mouldings is the weight, the undamaged ABS moulding weighs 23gm, the fibreglass repalcement, 17gm. Its only a few grammes of course and up at the front end doesn't affect the cg, but an interesting observation that fibreglass can be lighter than ABS.
  13. The mould, having now been used, benefits from the previous coats of release wax so only 5 coats were applied this time. Here, the second rocker cover is curing while the first one, after 30 hours is now sufficiently hard that it can be cut with a rotary disc. Its been cut right down to be as realistically proud of the cowl as I can make it (without being able to measure the real thing) leaving tabs which, once the cowl has been suitably slotted, will provide a firm fixing.
  14. Adhering to the regime of 8 coats of release wax, which really didn’t take too long, the halves were bolted together and given one last wax along the join, then laying up started. Two layers of 25gm cloth were applied, this was to ensure that the cloth followed the tight curves. After that 2 layers of 50gm cloth were applied and finally one layer of 80gm. The resin had cured sufficiently after 12 hours to undo the bolts and pop out the casting. It needs to fully cure before it can be trimmed, but the mould is free again to make the second casting.
  15. Apply it just as you would for wax furniture or car polish. I use an old bit of towel which remains in the tin. Its absolutely saturated with wax by now but that's probably an advantage. Apply liberally, let it dry for a few minutes then buff to a shine..........then repeat and repeat!
  16. Andy, I just use wax, this one. I've tried a few products, including PVA, but none seem as good as this stuff. The instructions on the tin say to apply 6 coats but I've found the more the merrier and at least 8. For subsequent lay-ups 5 or 6 are sufficient. A tin will last for years if the lid is replaced tightly.
  17. After another 24 hours, the second half of the cowl has been released from the plug and the excess from the edges removed. The next job is to bolt the two pieces together and start the waxing process again in preparation for the first rocker cover lay-up.
  18. Excitedly watching the resin cure, I decided that the mould wouldn’t be rigid enough with the few layers of 50 and 100 gm cloth applied, so added two 200gm layers. The right decision I think as after 24 hours the mould popped off the plug fairly easily without distorting and feels sufficiently rigid to be useable. Hot glue was used to fix the parting board supports to the base board; I find hot glue quite good for this sort of application as it holds joints together - just, so is easy to break away afterwards. I’d also recommend decorator’s caulk as the medium for gap filling between the plug and parting board. I’ve tried both Plasticine and Playdough in the past but neither are as effective as decorator’s caulk. Its resilient enough to withstand the laying up process but can be easily removed afterwards by a simple rub with a thumb and leaves no residue. The excess fibreglass was cleared away using a Permagrit rotary cutter in a rather ancient Minicraft hand-held drill – it will be a sad day when this drill packs up, I can’t guess how many models this has helped to construct. The cleaned up first mould half refitted and gap filled with decorator's caulk. A few more coats of release wax and then the other half can be laid up.
  19. SLEC will almost certainly have what you are looking for if you want to use a snake. https://www.slecuk.com/index.php?route=product/search&search=snake&category_id=0 If its a straight run from the servo to the control horn, you could use a carbon rod, these won't result in the trim change often associated with plastic snakes due to ambient temperature variation. https://www.bucks-composites.com/products?search_api_fulltext=carbon+rod On a rudder you'd probably not notice any trim change, its more likely to be noticeable on an elevator. If using a carbon rod, its preferable to support the rod at intervals to prevent whip.
  20. Digital and analogue servos can be interchanged. For most applications an analogue servo will be all you'll need unless you want to fly zippy models. Digital servos are generally faster and have greater holding power - this can be good and bad, if you stall a digital servo it will draw a very high current trying to reach its commanded position and may well burn out. A programmable servo will be digital, programmable can be useful in some applications if you want servo reversing, end point adjustment, servo slow etc and for whatever reason can't achieve it in the transmitter. For most scale models, gliders and sports models, an analogue servo will perform just fine.
  21. There had been a bit of damage to the extreme nose so a piece of balsa was grafted in and covered with glass cloth. After cutting back it blends in quite nicely, the trick will be whether the paint can be blended in as well. With the weather still not being suitable for painting outside, attention was paid to making a plug for the rocker covers. As well as the original ones in the kit being damaged, a bit of internet browsing showed that they were not a very good rendition of the Hispano Suiza direct-drive engine. Its possible that the bulges at either end were fairings, in which case they should be the same colour as the fuselage with only the straight centre part being black. I decided that as most SE5s didn’t have the fairings, the rockers should be less protruding and only showing a small bulge at the rear end, which I imagine is the valve timing gear housing. The plug was made from a couple of lengths of ½” balsa with a piece of 1/8” liteply at either end to form the shape, then a scrap piece of balsa both ends to allow a bit of a curve. The plug was then mounted on a board, standing proud by ½”, and covered firstly in two layers of 25gm cloth to better follow the curves, then one layer of 50gm cloth. After curing the surface was cut back, initially with 180 grade wet & dry then 240 grade. That gets a surface finish which is good enough for the subsequent coats of release wax. The next decision was whether to make a mould or simply to cast on the outside of the plug. Casting on the outside would be simpler but could lead to damage in trying to separate the parts and would also mean more rubbing down. I decided that, while a bit longer process, it was be safer to make a mould. 6 coats of Meguiar’s release wax were applied before mounting a parting board, cut from cheap 8mm B&Q ply, positioned along the centre line of the plug. The face was covered with parcel tape, the gap filled with decorator’s caulk and a further couple of coats of release wax to ensure that once the first layer of fibreglass was laid up, nothing was going to stick – always a trepid period. Here the first half has been laid up, it will be left for 24 hours to cure before putting those coats of release wax to the test! The reason for making a flange at the bottom is so that the mould can screwed to the board later and retain its shape and position while the second half is laid up.
  22. Richard, pleased to hear you are making progress. I played around with some offset hinges and did get the wing to fold just below the tailplane but the wing join wasn't pretty. As the model wouldn't be ready for this year, setbacks or not, I decided to concentrate on two other models in need of some repair and restoration which could be brought up to the painting stage by the time the weather improves. These are on track so hopefully I'll be back on the Vega Gull in the spring although I don't tend to get a lot done in the workshop during the warmer months. I'm resigned to having the Gull's wings fold well below the intended position, which won't affect the looks, once assembled, or the flying but of course will look very silly sat in the van. Us modellers have to be made of stern stuff!
  23. Steve, These Kavan hinges would be fine for your model, three for each elevator half would be sufficient. Before gluing, put a very light drop of oil on the pin and work it in, then glue the hinges with epoxy. Provided you've got some epoxy in the holes and a smear on the flanges, they won't pull out. Once you flexed the control surface a few times and satisfied yourself that all is moving freely, leave the glue to set. The pins are quite easy to remove by pushing with a flat bladed screwdriver rather than trying to pull them out with pliers. When the model is completed you can reinsert the pins or if you prefer slide a length of piano wire through them all, though this means you'll have to bend over one end and trap it in the wood.
  24. With all the basic work completed, the cowl was covered in 1/64 ply sheet. I would have like to have been able to do it with one piece but the sheet was only 12” wide and it would have required a piece 14.5” to go round. Attempting to curl the sheet across the grain wasn’t going to work so it had to be two pieces with the join along the centre line. The inside was given a coat of epoxy resin to prevent the inevitable fuel mist from soaking into the wood, then after filling a few low spots the outside was covered in 50 gm cloth. The newly resin coated cowl has been put aside for a couple of days to cure, then it will be cut back with wet & dry paper. The cowl here has been chocked off the board to prevent the bottom overlap from sticking to the building board or pulling away.
  25. Frank, I think it was about 6am when Sleipner went down in Gandsfjord. I was in bed in Stavanger and was woken by the thud!
×
×
  • Create New...