Flyer Posted February 15, 2020 Author Share Posted February 15, 2020 Ok, now trying to work out the deployment of the airbrake. I made a mock up to prove that I've got the general idea. Not sure why the picture does not show correctly, but blames new iPhone! The prototype is way out is shape over the shape shown on the plan, but this exercise was to establish the angles of the hinging. The opening mechanism should be a type of lever, from central, carbon push rod, transferred thro bell crank to 3mm pushrod and clevis. Edited By Flyer on 15/02/2020 14:18:28 Quote Link to comment Share on other sites More sharing options...
Flyer Posted February 25, 2020 Author Share Posted February 25, 2020 If I wanted to plank...…..... I'd have taken up boat building !!!! But almost progress Pics soon After I've found a few kg of filler ...…... cheers Ade Quote Link to comment Share on other sites More sharing options...
Martin Gay Posted February 25, 2020 Share Posted February 25, 2020 It will get easier on the second Sabre. "Practice makes perfect!" Quote Link to comment Share on other sites More sharing options...
Flyer Posted February 25, 2020 Author Share Posted February 25, 2020 Posted by Martin Gay on 25/02/2020 21:35:43: It will get easier on the second Sabre. "Practice makes perfect!" Thanks Martin, hoping to lay the second ( and longer) one down on Sunday. Hope to debut working airbrakes in situ too. Am I correct in noting that if I use a rudder, that the mechanism could be inline with the tail controls? Is it a case of clever bending of control rods around said elevator? Cheers Ade Quote Link to comment Share on other sites More sharing options...
Martin Gay Posted February 25, 2020 Share Posted February 25, 2020 Chris Barlow, and others, has made a hidden rudder linkage. Check out his build blog. The prototype used a snake whilst the Gamma used a closed loop system. Quote Link to comment Share on other sites More sharing options...
Flyer Posted March 2, 2020 Author Share Posted March 2, 2020 A little more done on fuselage one. Finally bought myself a cheap Balsa Stripper. Why had I not bought one years ago I do not know. This has made planking a lot lot easier, and has made it almost bearable! So, I now have two halves; tonight I will remove the second half off the building board to see if they line up. Hopefully I've built matching halves . Learning new skills all the time; I had thought that you cant teach old dogs new tricks............ I just perfect the ones I know!. Cheers Ade Quote Link to comment Share on other sites More sharing options...
McG 6969 Posted March 2, 2020 Share Posted March 2, 2020 ... oooh, Ade. I can't imagine you building all those years without a Master Airscrew balsa stripper. By the way, it's not a "cheap" tool, but 'elementary', my Dear Flyer. A bit like playing Fantasy GP without proper 'octopi'... Cheers Chris Quote Link to comment Share on other sites More sharing options...
Flyer Posted March 23, 2020 Author Share Posted March 23, 2020 Yesterday I managed to finally cut out the additional formers and lay down the keel of the second airframe. Used my new scroll saw for the first time; does that make me a 'real' modeler now? Or do I have to design and build first? Anyway, stay safe lads, and see you all on the hill when conditions allow. cheers Ade Edited By Flyer on 23/03/2020 07:55:25 Quote Link to comment Share on other sites More sharing options...
Flyer Posted April 6, 2020 Author Share Posted April 6, 2020 Well, spent the weekend trying to get a workable solution to the air brakes. It's not perfect, but I've worked out a solution, that should do the job. Just need to 3D print a connector to link the brake actuator to the brake, but that will not take long. The brake is held on the hinge bracket by a 2mm rod, which itself goes through a hole in the additional liteply bulkhead. The bracket itself will be bolted to that bulkhead, so could be removed if necessary. Once this is in position, I will glue balsa onto the brake to enable final sanding. Also, I'm trying to establish the maximum width of the canopy please. I have the height and length, but am struggling with the width. Cheers Ade Quote Link to comment Share on other sites More sharing options...
McG 6969 Posted April 6, 2020 Share Posted April 6, 2020 Hi Ade, I remembered your question when I was at La Grotte today, so if it can help you, the width of my canopy at the maximum width - ie. about 10 > 15mm behind the point where the full size canopy slides back - is 84mm. Hope this helps Cheers & keep safe Chris Quote Link to comment Share on other sites More sharing options...
Flyer Posted April 6, 2020 Author Share Posted April 6, 2020 Posted by McG 6969 on 06/04/2020 19:52:10: Hi Ade, I remembered your question when I was at La Grotte today, so if it can help you, the width of my canopy at the maximum width - ie. about 10 > 15mm behind the point where the full size canopy slides back - is 84mm. Hope this helps Cheers & keep safe Chris Thanks Chris, that helps me immensely. I hope to have two canopy plugs ready within a week! cheers Ade Quote Link to comment Share on other sites More sharing options...
Flyer Posted April 10, 2020 Author Share Posted April 10, 2020 Well, after putting it off for many days, I've finally made up the tail plane actuator. It was actually not as bad as I had thought, and many thanks to those of you that have given guidance. All I have to make now is the second set, but that's today's job. One question I have is regarding the tailplanes. Are you gluing this on permanently, or are the piano wire supports held by friction in tubes set into the tail planes? Finally, I've now glued up my blank for the canopy plug. The canopy itself is close to 19 inches, and I'm making the plug out of mdf. I find that this gives a good plug, and will handle the pressure of being moulded without distorting. The final finish on it is P38 body filler, which when polished with wax, allows a good release of the PETG once pulled. I'll be shaping the blank over next few days; pics to follow. Cheers Ade Quote Link to comment Share on other sites More sharing options...
McG 6969 Posted April 10, 2020 Share Posted April 10, 2020 Hi Ade, I remember reading some builders kept the tailplanes on just by friction with only a spot of Pritt, while others are gluing them at the very end of the build - ie. after glassing and painting. As I have no dihedral with my Dog, I think I will glue them at the end. Maybe some Sabre guru can jump in to help? Cheers Chris Quote Link to comment Share on other sites More sharing options...
Martin Gay Posted April 10, 2020 Share Posted April 10, 2020 I don't glue the tailplanes on. I have yet to lose one in flight. It also makes storage easier. Quote Link to comment Share on other sites More sharing options...
Flyer Posted April 20, 2020 Author Share Posted April 20, 2020 Cheers Martin, I'll give that a go. I've struggled to get a working solution for the air brakes. I was going to use a connector to join both brakes together, but, on reflection, I think I'll use individual min servos, as it will have less slop in the system, and also allow a little bit of adjustment on each airbrake. I will now have an access hatch under the fuselage, 'just in case'. There are hand holes in the formers, which are approximately where I need the mechanism to go. I've 3D printed some plastic 'bearings' to give smooth operation of the brakes. The servo will pull the linkage to open the brakes, and push to close. I attach a few pictures that hopefully show the detail. The hinge line is not vertical, which does give a small droop on opening, however, I'm not sure if it's enough. Balsa will now be added to the profile on the outer face to blend in with the fuselage. A thin balsa 'box' will be added inside to clean up the install, and this will be fitted before joining the two halves. cheers, Ade Quote Link to comment Share on other sites More sharing options...
dirk tinck Posted April 20, 2020 Share Posted April 20, 2020 It will be fine once the balsa is on the brakes Ade. Looks good!It will be easyer than my system to blend them in with the fuse too! Quote Link to comment Share on other sites More sharing options...
Flyer Posted May 10, 2020 Author Share Posted May 10, 2020 Finally got myself motivated enough to start shaping the canopy plug. It is a sadly satisfying way to spend a few hours with the radio on in the workshop. I transferred the basic shape onto the blank by using carbon paper under the hand-drawn sketch. Then a little electric planning to give an approximate shape. Then onto the coarse sanding file. I reckon I'm around half ay there on shaping, and then will be a few applications of P38 filler, along with several coats of high build primer. I am also intending to use the plug to make a fibre glass canopy frame as per Dirk's method. They really finish off the look. Cheers for now Ade Edited By Flyer on 10/05/2020 18:45:07 Quote Link to comment Share on other sites More sharing options...
Martin Gay Posted May 10, 2020 Share Posted May 10, 2020 Looking good so far Ade. Keep up the great work as I have a fuselage awaiting just such a canopy! Martin. Quote Link to comment Share on other sites More sharing options...
Flyer Posted June 3, 2020 Author Share Posted June 3, 2020 Mojo found !!!! Have spent last few evenings sanding and filling canopy plug, so will be pulling canopies tomorrow evening. I've now just about given up with the airbrakes with regard to getting them to droop correctly. I will be going with what I have now. At least I'll be onto my favourite part soon; making the wings! The following picture shows the rear part of the canopy I've been trying to replicate. Quote Link to comment Share on other sites More sharing options...
Martin Gay Posted June 4, 2020 Share Posted June 4, 2020 Looking great, Ade. Edited By Martin Gay on 04/06/2020 07:21:35 Quote Link to comment Share on other sites More sharing options...
McG 6969 Posted June 4, 2020 Share Posted June 4, 2020 Keep up the mojo, Ade. Looking forward to (finally) seeing your stretched canopy... Cheers & stay safe Chris Quote Link to comment Share on other sites More sharing options...
Flyer Posted June 4, 2020 Author Share Posted June 4, 2020 Here you go Chris, Not as good as I'd like, but materials are limited at moment, so it will have to do. Two boxed up for yah Martin . Now to finish the air brake install and connect those servos and I'll be able to join the fuselage halves. Cheers Ade Quote Link to comment Share on other sites More sharing options...
McG 6969 Posted June 4, 2020 Share Posted June 4, 2020 ... superb, Ade. Cheers, young man Chris Quote Link to comment Share on other sites More sharing options...
Flyer Posted June 4, 2020 Author Share Posted June 4, 2020 Thanks Chris, but it's not as good as I had hoped. But hopefully close enough to scale to stop the scale police creating a fuss . Fortunately, only a few aircraft were ever made, so documentation is fairly scarce. But don't tell everyone...…. cheers Ade Quote Link to comment Share on other sites More sharing options...
McG 6969 Posted June 4, 2020 Share Posted June 4, 2020 ... no probs, Ade. I will be as silent as an 'octopus'... Cheers Chris Quote Link to comment Share on other sites More sharing options...
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