Bob Cotsford Posted September 19, 2015 Share Posted September 19, 2015 Nice engineering Jez. Now will you please stop posting, you're making me feel inadequate Seriously, nice engineering in miniature Edited By Bob Cotsford on 19/09/2015 09:14:47 Quote Link to comment Share on other sites More sharing options...
Jez Harris 1 Posted September 19, 2015 Author Share Posted September 19, 2015 A bit more tinkering with the detail now.. Another one of the key bits of the Moth are the compasses - they are very visible! I wasnt looking forward to this as the supplied vac formed ones looked naff..They were formed on the same sheet as the panel surrounds and padded cockpit back rests so they are textured.. So I went on the recycling hunt again - this time for suitable sized discs.. An empty glue bottle makes a great source of tubing for the body.. Now I will admit that at this point I got lost in the moment and forgot about the camera.. But grey paint, some stuck on dials, a dodgy stuck on name plate (thats actually a sticker for prop info) and a few Mick Reeves gorblimey screws later..... I'm really happy with this! Just got to make the little Compass lock... Jez Edited By Jez Harris 1 on 19/09/2015 09:25:27 Quote Link to comment Share on other sites More sharing options...
ceejay Posted September 19, 2015 Share Posted September 19, 2015 Aaah!! i see no probs mate just send it along, liking/wanting a moth seeing this, chris Quote Link to comment Share on other sites More sharing options...
Jez Harris 1 Posted September 19, 2015 Author Share Posted September 19, 2015 Posted by ceejay on 19/09/2015 10:32:38: Aaah!! i see no probs mate just send it along, liking/wanting a moth seeing this, chris Cornish Pixie is selling his - the one Matt used to own....the one that got me into building this one...... Go on - you know you want to...go on.....go on.... go on.... Jez Quote Link to comment Share on other sites More sharing options...
ceejay Posted September 19, 2015 Share Posted September 19, 2015 would love it mate,, out of my price bracket unfortunately, have been perusing the MR website and am quite taken by his plan/kit/bits. Mmmmmmmmmmmm tiger moth chris Quote Link to comment Share on other sites More sharing options...
Jez Harris 1 Posted September 19, 2015 Author Share Posted September 19, 2015 Time for some struts. I hate struts with a passion usually...my other Biplane builds have been WW1 stuff which have involved hours of initial shaping, gradually decreasing grit sizes of sandpaper to achieve a dead smooth finish, followed by staining and layers of varnish...all messed up with 2 different lengths and different profiles leading to confusion when assembling at the field or having to resort to some sort of markings. Moths often have stained wood but the scheme I have chosen has painted fabric covering..RESULT!! plus all the struts on Moths are identical in length and profile...YAY!!! Heres a couple of pics of a full size showing firstly the layout and then the metal work at the end.. So I started by shaping some blanks.. The it was out with the brass work again...strut ends and some shaped plates - I annealed the plates to allow me to shape them - for brass you heat it until cherry red then quench in water. A quick spray of etch primer.. Next up I epoxied the strut ends into the struts.. Yet more solartex... Then I shaped the strut end caps.. Sorted..I just need to cross drill and pin through them..another job ticked off! Jez Quote Link to comment Share on other sites More sharing options...
Tim Hooper Posted September 19, 2015 Share Posted September 19, 2015 You're making this look all too simple. I know it's not really...... tim Quote Link to comment Share on other sites More sharing options...
Jez Harris 1 Posted September 19, 2015 Author Share Posted September 19, 2015 Posted by Tim Hooper on 19/09/2015 21:29:19: You're making this look all too simple. I know it's not really...... tim All Moths now have to be done this way..... Hows urs coming on? Jez Edited By Jez Harris 1 on 19/09/2015 22:55:46 Quote Link to comment Share on other sites More sharing options...
Jez Harris 1 Posted September 20, 2015 Author Share Posted September 20, 2015 I've just noticed there is a part built one of these Moths for sale on the classifieds section!! However I think £700 is too much for a part built - I paid that for my totally unstarted one... Might be interesting to see some photos of it to see how much has been done. If anyone needs to know if the kit is fully complete I would be willing to help out.. Jez Quote Link to comment Share on other sites More sharing options...
tim mock 1 Posted September 20, 2015 Share Posted September 20, 2015 Jez I'm a bit disappointed that you have made negative comments as to the value of my Heron Tigermoth kit as advertised in the classifieds. I was under the impression that forums were for the general good of the subject and as a fellow modeller I find this less than helpful. Your opinion that a part build model is of less value than a virgin kit may well be true to some but this kit/model has an interesting history and provenance that could to some increase its value beyond your perceived valuation. Although I chose not to include that info in the advert, I wasn't expecting to have to defend the advert to uphold its credibility. Your offer to help with the audit of kit contents is most welcome. Best Wishes Tim Mock Quote Link to comment Share on other sites More sharing options...
Stevo Posted September 20, 2015 Share Posted September 20, 2015 Ummm... err... wow. <speechless> Subscribed! Quote Link to comment Share on other sites More sharing options...
Tim Hooper Posted September 20, 2015 Share Posted September 20, 2015 Posted by Jez Harris 1 on 19/09/2015 22:32:38: Hows urs coming on? It's very, very simple compared to yours! Tail surfaces done, and started on the fuselage. No instructions - just an exploded view of the components! tim Quote Link to comment Share on other sites More sharing options...
Jez Harris 1 Posted September 21, 2015 Author Share Posted September 21, 2015 Bit more achieved the weekend.. Finished the struts - they are all drilled through and bolted and the brass ends have been crimped a bit.. Bit more detail... The airspeed indicator is ahem - basic - its mounted on the front left strut - the breeze pushes against a little flag mounted on a sprung arm - this pushes it backwards and you read off against a scale..Heres the full size.. In the kit you get the back plate for it but nothing else.. I had kept some scrap bits of litho from the off cuts.. So - a bit of cutting, folding, slicing a groove, bending a spring, adding a nut and bolt and printing a scale on the laptop later...The spring looks a bit thick so I might change it later.. Edited By Jez Harris 1 on 21/09/2015 10:55:31 Quote Link to comment Share on other sites More sharing options...
Jez Harris 1 Posted September 21, 2015 Author Share Posted September 21, 2015 I also managed to get the oil tank sorted.. That comes as a simple moulding.. So a nut in the bottom right corner becomes the drain plug (I've used a fitting from a filler kit so might be tempted to use it as the fuel filler point) A length of carbon tube and the top off an old tube of oil paint becomes the filler cap and tube. A dozen or so screw holes - All primered up ready to go..sorry about blurry pic.. Quote Link to comment Share on other sites More sharing options...
Manish Chandrayan Posted September 21, 2015 Share Posted September 21, 2015 Looking good there Jez, you should get more weekends Quote Link to comment Share on other sites More sharing options...
Jez Harris 1 Posted September 21, 2015 Author Share Posted September 21, 2015 Posted by Capt Manish Chandrayan on 21/09/2015 14:04:24: Looking good there Jez, you should get more weekends If only - my hand is at a point where I can go back to work so wednesday will see a reduction in modelling output.. Jez Quote Link to comment Share on other sites More sharing options...
Jez Harris 1 Posted September 21, 2015 Author Share Posted September 21, 2015 Back to those magneto switches.. A couple of years ago I refurbished a 1/3rd scale cub. As part of the job I added a set of instruments to replace the sticker it came with. I used some stuff from Aerocockpit - great stuff at decent prices..**LINK** I had some switches left over.. So I trimmed them down and stuck them to a cardboard backing.. Sprayed them back and fitted them from behind.. Jez Quote Link to comment Share on other sites More sharing options...
Manish Chandrayan Posted September 21, 2015 Share Posted September 21, 2015 Good to hear about your hand and that you are getting back to work. All the best Quote Link to comment Share on other sites More sharing options...
Jez Harris 1 Posted September 22, 2015 Author Share Posted September 22, 2015 For the next couple of jobs I need to get the fus back on its wheels so its temporarily back on with the U/C.. I think this is the first time its had wheels on. Just need to fit the fairings on the legs and get hold of an old inner tube to make the gaitors - Anyone got an old one from a racing bike? - need a skinny one! First job was to stick the engine back on to get the carb bend and carb mounted..This would allow me to make a new top part of the cowling. And this is where its all gone a bit odd..This kit is supposedly built around a 62 Zenoah - The combined exhaust and mount shown above does the Z62 and nowt else. To stop the carb poking out the side cheek of the cowl you need to fit a 90 degree carb bend and a thinned down carb insulator. The instructions tell you to reduce the spacer to 7mm and fit it between the bend and the carb. The picture below gives a hint as to the first problem..This is taken WITHOUT the insulator in place. There is no way you can fit the spacer as the carb body would foul the exhaust. So what if I was to fit the insulator between the head and the carb bend? - all it does is remove heat transfer and this stops the fuel vapourising befoe it gets to the motor.. This is where it gets worse still...The reason for fitting the carb bend in the first place is to stop the carb fouling the cowl cheeks... Well this is where I am with the totally uninsulated carb bend install - The framework that holds all of the cowling pieces hits the carb still..On the right hand side you can see the green framework of the left hand frame - its in the right place. On the left of the pic you can see how far out the other side of the frame is. Thought about moving the engine a few degrees off vertical but that would make it worse. Hmmm - suggestions on a postcard please.. I cant change the position of the framework either as this sets the height of the cowl cheeks and top. This pic makes it look as if you could trim the frame a bit and take it over the top of the carb that way. Trust me - it wont. Jez Edited By Jez Harris 1 on 22/09/2015 08:34:43 Edited By Jez Harris 1 on 22/09/2015 08:49:14 Quote Link to comment Share on other sites More sharing options...
reg shaw Posted September 22, 2015 Share Posted September 22, 2015 On the two I've done I had to thin down the structure of the side frame to allow space for the carb to slide between it and the exhaust. It is very tight however. I also think I have a carb bend I made up which swings the carb down about 3/4 of an inch so there is more space for it. I'll have a look when I get home. Could you fit two thinner isolators, one at either end of the bend? I may have some pics too. Ian. Quote Link to comment Share on other sites More sharing options...
ceejay Posted September 22, 2015 Share Posted September 22, 2015 Hi Jez looks to me like you may need to make a custom inlet manifold, cant tell exactly without seeing it, but it looks like there is space to take the carb further back clearing the exhaust with a suitably angled extension twixt carb and bend, but this will no doubt require several coats of thinking re throttle arms/linkages etc!! But first off I would ask Simon (always broke on here I think!!) to post a pic of the one he has, or Ian if he has one, as I am positive this was exactly the set up they had, failing that just get rid of it!!! there's always a moth sized space in my workshop!! cheers mate beat me too it Ian!! Edited By ceejay on 22/09/2015 09:36:18 Edited By ceejay on 22/09/2015 09:38:38 Quote Link to comment Share on other sites More sharing options...
onetenor Posted September 22, 2015 Share Posted September 22, 2015 Have you been to your local air handling suppliers or plumbers merchant to see what fittings they have that you you may be able to use or adapt .Or a spray paint equipment suppliers . There are all sorts of short and close coupled bends that may be adaptable. Air suppliers and spray stuff suppliers use a lot of ali fittings .Plumbers largely brass. Plastics / nylon is an iffy area because of the heat Some of these fittings are also malleable / bendable to some extent with the proper tools. It's worth a look see. A close coupled bend for instance has a spigot / male end and a female end which means that the bend takes up a lot less space in the system . I can't show a pic. but if you get a Screwfix or Tool Station catalogue you can see what I am talking about by looking through the plumbing section. Love the build so far. I have a part built Practical Scale model but can;t finish at the mo due to not being able to walk much . Bad hips means /I can't get into shed. Quote Link to comment Share on other sites More sharing options...
tim mock 1 Posted September 23, 2015 Share Posted September 23, 2015 Jez Fitting the insulator between the head and bend will cause a cold bend and throttling problems due to condensing cold air just like full size aircraft and the need to select 'carb heat on' when taking off and landing, both critical occasions when a reliable throttle is needed. It will need an insulator between carb and bend to stop a hot carb vaporising causing difficult hot starts and poor throttle pick up from idle. You might have to fabricate something to satisfy both to keep the carb within the cowl. The bend is easy enough but the pressure pipe might have to be an external fitting with tygon tube direct into the crankcase. Another mod you might consider is fitting a pressure compensating pipe to the carb.When engines are fully cowled a pressure difference can occur in a dive etc within the cowl that affects carb metering. If you look at the carb on one side there is a removable plate with a small venting hole in.This is the atmospheric hole where the diaphragm beneath it responds to atmos pressure. The mod is to solder a small brass tube into the hole(removed)and push on tygon tube and lead this back into the fuz and undisturbed air ie normal pressure. Hope this helps Been there, done that, crashed and figured it out ! Regards Tim Quote Link to comment Share on other sites More sharing options...
reg shaw Posted September 23, 2015 Share Posted September 23, 2015 Hi Tim, I'm not disputing the full size facts bit but I've fitted the isolator to either end and a bit of both a few times with Zenoahs and they perform as reliably as ever once set up. Ian. Quote Link to comment Share on other sites More sharing options...
Jez Harris 1 Posted September 24, 2015 Author Share Posted September 24, 2015 Had a fiddle... First off fitted a 2mm insulator at the junction between the bend and the carb..got another on order to go between the head and bend It now fits - just! I've also re-made the side frame on the carb side of the engine... Ian - You werent joking when you said it was tight!!!! Alignment is still ok.. I love the scale catches. Next problem is the top of the cowl. The supplied one doesnt fit! With the back aligned in the right place...... Its a good few milimetres short.. I spent a fair bit of time checking and re-checking the bits I have made - especially the side frames - Everything is spot on. The cowl cheeks fit properly, the cowl bottom panel is fine and the prop driver is in the right place. I can only assume I have a duff cowl top. I think the solution will be to clad the existing part in lithoplate, adding a former to support the front. Thats a job for tomorrow. Jez Edited By Jez Harris 1 on 24/09/2015 21:08:52 Quote Link to comment Share on other sites More sharing options...
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