Mowerman Posted January 25, 2015 Share Posted January 25, 2015 I started back in November by persuading SWMBO to buy a laser cut pack plus extra wood pack as a combined birthday and 'xmas' present. This duely arrived dead on time - my birthday on the 19th. Not long after I saw that anyone signing up for the mas build could get a discount on the packs just too late for me. Having resisted the temptation to open the packs until after the hols I made a start by releasing the parts from the sheets of balsa and ply, big mistake as the dust started me coughing,sneezing and wheezing for a week. The lesson learned being always wear a dust mask and use a vacuum cleaner as you go. I'm not sure which was the worst the ply sawdust from the CNC milling or the balsa charcoal dust from the laser cutting. Edited By Mowerman on 25/01/2015 15:49:26 Quote Link to comment Share on other sites More sharing options...
Mowerman Posted January 25, 2015 Author Share Posted January 25, 2015 Photos of my progress so far are in my Jocasta album. One query - in the wood pack are 3 lengths of 1/4" x 1" hard balsa that I can not work out what they are for, any suggestions? Quote Link to comment Share on other sites More sharing options...
Mowerman Posted January 27, 2015 Author Share Posted January 27, 2015 When looking at the fuselage sides I wondered what would be the best way to glaze the side windows. As a test I took the cut out parts, chamfered their edges then placing them over the side panels with oclear acetate sheet between I pressed down with my travel iron ( temperature set higher than when used for covering ) and formed the acetate as shown in my album. I am hoping that if these are fitted after covering they willnot look too bad, especially if the covering can be carried into the edges of the cutouts. Quote Link to comment Share on other sites More sharing options...
Jim Newberry - Nuviation Ltd. Posted January 29, 2015 Share Posted January 29, 2015 Hi Mowerman, great to see another Jocasta taking shape, the pictures look good! In case you are not aware, there is a build blog on this model that I started some time ago - it has had a lot of input from a lot of people and has now grown to a mine of useful information so I would recommend having a look through that if the mood takes you. There are one or two discrepancies in the plan which cropped up between the drawings and the print run - my build blog will uncover all the wrinkles if you haven't already discovered them but if you need me to summarise, let me know and I'll list them. Most of them seemed to be in the fuselage, and since yours is clearly almost complete I would imagine you have uncovered them all! If any points of confusion arise, please let me know and I will be happy to help out. As for the 1/4" x 1" strips, well I had no input into the production of the wood packs so I am speculating now but my guess would be that two of the strips are for the leading edge while the third will be to make up the linings of the aileron cutouts. When it comes to building the wings, please note that there is a misprint on the plan which could lead you up a blind alley - the outer rib is a full length rib whereas the plan suggests that it stops at the front of the aileron. The drawing is accurate but the number assigned to the rib is incorrect - it is shown as R4 when it should be the same shape as R2. The situation is easily remedied (even if you have already built the wing before reading this) but I wanted to draw it to your attention. Best wishes, Jim Quote Link to comment Share on other sites More sharing options...
Mowerman Posted January 30, 2015 Author Share Posted January 30, 2015 Hi Jim Thanks for that, Unfortunately the wings are built with the short outer ribs so I will cut a couple of ribs to the full outline and stick them on. Other than that (and the dust), no problems so far. Quote Link to comment Share on other sites More sharing options...
Jim Newberry - Nuviation Ltd. Posted January 30, 2015 Share Posted January 30, 2015 Ah sorry about that! Glad to hear all is well otherwise. Quote Link to comment Share on other sites More sharing options...
Mowerman Posted February 1, 2015 Author Share Posted February 1, 2015 Jim You were right about the 1"x1/4" , what put me off was it was much wider than needed had to plane off almost 1/4" also it was very hard balsa. I also noted that the tabs on the fuselage formers dod not fit flush with the outside of the side panels so I fitted short bits of 1/16" x1/4" balsa (some filler may still be needed) I have modded the ailerons by fitting 2 extra ribs spaced 1/16" apart to take home made horns (1/16" thick 'plastic card' Photos in my album Edited By Mowerman on 01/02/2015 16:09:16 Quote Link to comment Share on other sites More sharing options...
Jim Newberry - Nuviation Ltd. Posted February 2, 2015 Share Posted February 2, 2015 It's a shame about the grade of balsa used, I must admit, I would love to start a kit manufacturing business where I had compete control over the grades of wood use for every part. I'm getting closer to the idea every day but until then I am stuck in the position of having no control over the process. As for the thickness, the problem is that it is not economical for producers to supply a small number of non standard sized parts so 3/4" width would be too small whereas 1" requires a lot of planing. Again, if only I had my own business... Of course, when I built the prototype, I cut the leading edge stock from a piece of 1/4" sheet which was exactly the density I wanted and just the right width! Sadly, such flexibility is just not possible with commercially produced parts. Quote Link to comment Share on other sites More sharing options...
Mowerman Posted February 13, 2015 Author Share Posted February 13, 2015 A week of no building but motor and E,S,C arrived from Airtek .Ordered yesterday PM delivered this morning. Sadly the motor delivered was 790kv not 900kv as ordered, I will keep this as I have not yet decided what battery pack to use to get the C.G. fight and can always juggle prop size. Checking the motor against the plan i found that the plan shows the motor length to be 35mm but the actual length is 52mm. And then - OH bother I saw that the front fuselage was off set to the left, must have shifted as the glue dried, what to do now? I have two options - leave it as it is ,compensate with side thrust and hope no one notices or chop it off at F3 and re-build the front /cowl area. Any other suggestions? Quote Link to comment Share on other sites More sharing options...
Mowerman Posted February 13, 2015 Author Share Posted February 13, 2015 Strange ! I just checked the instruction leaflet that came with the motor and it gives the length as 34mm. Quote Link to comment Share on other sites More sharing options...
Jim Newberry - Nuviation Ltd. Posted February 13, 2015 Share Posted February 13, 2015 Hi Mowerman, It might be worth giving George at 4-Max a call - I've always found him to be very helpful so it might be that you have been sent the wrong motor. The power set recommended on the 4-Max website differs slightly from the one I originally used as George felt it would be better suited to the model but it does state that the motor is a 900kv job. I'd give him a call if I were you. Jim. Quote Link to comment Share on other sites More sharing options...
Mowerman Posted February 14, 2015 Author Share Posted February 14, 2015 Hi Jim Motor from Airtek Hobbies Same spec, (3548/900/4) but £25.95 including mounting kit and prop driver. Had good service from them before. Had a close look at the fuselage front and found that the left side had cracked at F3,despite wetting with water/ammonia mix, should have been more careful. Perhaps a couple of half depth saw cuts in the inner faces of the sides at this point would help (the sides are quite hard balsa) Just an aside, as a kid I would occasionally watch a local carpenter at work' sometimes making coffins. In order to get the side panels to bend at the shoulder he would make seven saw cuts across the panel to about half thickness. This produced a smooth curved bend. Could we take a tip from an old craftsman? I wonder if the seven cuts was significant ? Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted February 16, 2015 Share Posted February 16, 2015 The more cuts, and closer together, you can make then the smoother the curve...but... even 1 cut removes some strength from the wood. The strength can be recovered by either filling the cuts with a glue or laminating the inside of the curve after gluing with an thin strip of the same material. Another significant point about the seven cuts is that they're only to half thickness depth. This is to remove the material that would otherwise be in compression in the curve, the centre being neutral and the outside of the curve being in tension. Quote Link to comment Share on other sites More sharing options...
Mowerman Posted February 26, 2015 Author Share Posted February 26, 2015 Chris I realize the cuts are only half thickness but I wondered if there was some significance in the specified 'seven' Sorry Alain I fail to see the connection. Quote Link to comment Share on other sites More sharing options...
Andy G. Posted February 26, 2015 Share Posted February 26, 2015 That's because Alain Richard is a SPAMMER.. Check his other 5 posts.. all to mobile phone accesories.. Suggest Mods eject him from the forum.. ( I have just reported him to moderators) Edited By Andy G. on 26/02/2015 16:22:43 Quote Link to comment Share on other sites More sharing options...
Pete B Posted February 26, 2015 Share Posted February 26, 2015 Thanks Andy - he's history...... Pete Quote Link to comment Share on other sites More sharing options...
Mowerman Posted February 27, 2015 Author Share Posted February 27, 2015 Thank you both. I see the politicians are talking about making cold calls illegal, perhaps they should do the same with 'spam'. . Quote Link to comment Share on other sites More sharing options...
Steve T Posted February 27, 2015 Share Posted February 27, 2015 Well done Andy, I was looking at the Alain posts yesterday and did wonder what on earth was going on with those links. Thought I was going even dafter than normal, how on earth did that sad individual even get on here? Quote Link to comment Share on other sites More sharing options...
Mowerman Posted March 12, 2015 Author Share Posted March 12, 2015 No progress for over a month now due to chest problems caused by balsa and plywood dust. Yesterday I started to clear my bench and triggered two hours of sneezing,coughing and wheezing. As it was only a case of moving a few bits off the bench I failed to use the safety mask that I had for spraying. What do others use? Edited By Mowerman on 12/03/2015 16:29:44 Quote Link to comment Share on other sites More sharing options...
Mowerman Posted March 31, 2015 Author Share Posted March 31, 2015 Made a bit of a mess when joining the wings with glass and epoxy not a good finish but sorted with disc sander! then light glass cloth and WBV (Wilco). Now started covering (GS film) the wing. If I ever build another wing this big I will first modify the plan to make the wing Two piece. Or get a bigger workshop. Quote Link to comment Share on other sites More sharing options...
Mowerman Posted April 3, 2015 Author Share Posted April 3, 2015 SWMBO saw the above post and insisted - "smaller models" Quote Link to comment Share on other sites More sharing options...
Den Moran Posted April 29, 2015 Share Posted April 29, 2015 Help! I've made up a report with pictures about my build for 'Jocasta' , but cannot 'paste' it here with the pictures. The site keeps asking me to copy and paste each one, with an added CTRL + V thingy as well - pretty laborious! Please don't tell me it's my browser, unless a suggestion on how to modify it comes as well! Ta muchly , fellow Jocastites, Den Quote Link to comment Share on other sites More sharing options...
Mowerman Posted April 29, 2015 Author Share Posted April 29, 2015 Mine is finally built. Now I look at it and think 'what an ugly brute' I covered it with yellow film because I had a roll that I bought by mistake Batteries arrived and charged, all connected, testing with watt meter only getting 250 watts from motor rated at 690 watts. Waiting response from supplier. Quote Link to comment Share on other sites More sharing options...
Andrew767 Posted April 29, 2015 Share Posted April 29, 2015 Posted by Mowerman on 29/04/2015 18:45:48: Mine is finally built. Now I look at it and think 'what an ugly brute' I covered it with yellow film because I had a roll that I bought by mistake Batteries arrived and charged, all connected, testing with watt meter only getting 250 watts from motor rated at 690 watts. Waiting response from supplier. Roy Have you tried another prop?....greater diameter or greater pitch. Andrew Quote Link to comment Share on other sites More sharing options...
Mowerman Posted April 30, 2015 Author Share Posted April 30, 2015 Andrew Prop in use is 14x7 as motor spec for 3s, not happy to go much bigger due to ground clearance issues. Quote Link to comment Share on other sites More sharing options...
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