trebor Posted December 18, 2017 Share Posted December 18, 2017 Has anyone got some hot tips for getting the valve collet ( thingamijigs ) back in ? My thumbs too big Link to comment Share on other sites More sharing options...
Jon H Posted December 18, 2017 Author Share Posted December 18, 2017 Posted by trebor on 18/12/2017 12:17:01: Has anyone got some hot tips for getting the valve collet ( thingamijigs ) back in ? My thumbs too big Get smaller thumbs. A permagrit sander should whittle them down Alternatively, make a wooden block that sits in the combustion chamber so you can push down on the valves and not have them fall out. If you then put a drop of oil on the valve stem it should help the collet stay put. I do sympathise, fitting collets is a job i really do not enjoy 1 Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted December 18, 2017 Share Posted December 18, 2017 Get the wife to help? Link to comment Share on other sites More sharing options...
trebor Posted December 18, 2017 Share Posted December 18, 2017 Get the wife to help no chance ! She's blind as a bat. I did it but if I had more to do I would have to make something. Link to comment Share on other sites More sharing options...
trebor Posted December 18, 2017 Share Posted December 18, 2017 Update, whilst working on second head a valve spring and retainer sprung off somewhere in the workshop Link to comment Share on other sites More sharing options...
Jon H Posted December 18, 2017 Author Share Posted December 18, 2017 There are dents in the ceiling here caused by flying valve springs. I take it you are going to need a few spares? 1 Link to comment Share on other sites More sharing options...
trebor Posted December 18, 2017 Share Posted December 18, 2017 I found them they hit the window, the retainer was on the window sill and the spring ended up in a plane cockpit as it shot back into the room Link to comment Share on other sites More sharing options...
Gordon Whitehead 1 Posted December 18, 2017 Share Posted December 18, 2017 Ref the chicken hopper tank, thanks very much for your clear diagram and explanation Steve. I turned the diagram upside down to check what would happen under negative "g" in an aerobat, eg my Jungmeister - not a normal Spitfire orientation. Fuel would drain back from the small tank to the large one though the air release line, the greater the "g", the faster the draining. It would take a very prolonged period of -ve "g" to empty even a 4oz tank so there's probably not much to worry about. However, it struck me that one could install a Kavan one-way valve in the air release line to minimise drain back. I have been thinking of trying a hopper tank system in my Jungmeister, as there's only room for a small tank in the lower fuz which is fine for the currently installed Saito 36-FG which will run for half an hour on 10oz of petrol. However, I want to replace the Saito with my Laser 300 running on glow for about 30% more power, and mounted inverted. This will need about 24oz of juice for sufficient duration per Laser recommendation. A 16oz main tank and 8oz twin clunk lower tank arranged per Steve's diagram will fill the bill, and I already have a Kavan one-way valve to try in the air release line if it proves necessary. Gordon Link to comment Share on other sites More sharing options...
Steve Dunne Posted December 18, 2017 Share Posted December 18, 2017 Thanks for your comments Gordon, The inverted flight issue interested me also. I did try flying the Spitfire inverted up and down the strip - not circuits! with inverted flight periods of 12-15 seconds. I could detect no issues. My Jungmeister (Laser 155) flies inverted also in 12-15 second passes. I do not try full circuits inverted, it would not look scale - I leave that to the Acrowots and 3D guys! I don't think you will have an issue unless you go for extended inverted flights or too many consecutive bunts . Suggestion - go for a 20-24oz top tank - that way you get your full flight without emptying the sub tank - extra safety! The Spitfire is 20oz to 4oz, and a 10-12 minutes flight leaves the top tank stil 1/4 full or so. Steve. Edited By Steve Dunne on 18/12/2017 19:27:54 Link to comment Share on other sites More sharing options...
Gordon Whitehead 1 Posted December 18, 2017 Share Posted December 18, 2017 Thanks Steve. The 20-24oz top tank is a better idea, and with all the extra power and thrust the additional fuel weight won't be a problem. I was only thinking of 16oz and 8oz tanks as I already have them. I now intend making a start on the 300 installation in the near future. It's already been in the Jungie during my experiments on petrolizing it a while back so the mounting system is ready to install. Gordon Link to comment Share on other sites More sharing options...
TartanMac Posted December 18, 2017 Share Posted December 18, 2017 Just wondering if there is a way to reverse engineer the chicken hopper tank system. I am going to put my 150V in upright so the carb is a little high but the bonnet is not far off the same hight was just wondering if I could fit something shallow or low height wise with a tank underneath. Or can I have the fuel line at the top of the tank ? What would that do inverted ? Link to comment Share on other sites More sharing options...
Jon H Posted December 19, 2017 Author Share Posted December 19, 2017 If the tank is low then you arent likely to have any problem. As long as its not miles out the engine will draw fuel without any trouble. If it is a problem, a pressure nipple would more than likely take care of it. Link to comment Share on other sites More sharing options...
Steve Dunne Posted December 19, 2017 Share Posted December 19, 2017 TartanMac - my FW190 has the Laser 200 V twin upright, fuelled from a tank over an inch lower that the carburetters line (with two clunks). It draws fuel fine in all attitudes... Link to comment Share on other sites More sharing options...
Chris Walby Posted December 19, 2017 Share Posted December 19, 2017 New boy question No1 while converting my BH Speed Air from electric to Laser 70 Is it better to align the engine toward the top of the fire wall or the bottom as the tank can be moved to accommodate either position + I'll have to re-engineer the front wheel pivot anyway. Question No 2 The SLEC tank shows/describes both vent tubes pointing up...as the 70 does not need pressurized tank should I point one up and one down and just use them as fill (as vent facing forwards) and drain respectively? Lastly the crankcase vent I assume just needs a short pipe pointing towards the ground? Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted December 19, 2017 Share Posted December 19, 2017 Posted by Steve Dunne on 19/12/2017 09:45:10: TartanMac - my FW190 has the Laser 200 V twin upright, fuelled from a tank over an inch lower that the carburetters line (with two clunks). It draws fuel fine in all attitudes... Oooh giz a go, lovely. Link to comment Share on other sites More sharing options...
Jon H Posted December 19, 2017 Author Share Posted December 19, 2017 Hi Chris If you can find them there might be some marks on the firewall in a cross pattern. These will represent the intended centreline and should be used for reference. If they arent there, mount the engine as high as you can. It will help with prop ground clearance as much as anything else. Having the crank in line with the middle of that red stripe on the fuselage is likely to be about right. For the tank, you can either have a fill, a vent, and a clunk. Or you can have only a clunk and vent line with the pipe to the caburettor used for filling. I have done this many times as its easy to pull the pipe off, fill it, and pop it back on. My current 70 powered twin has this setup. The crankcase drain line should just be vented away from the fuselage as described in the instructions Link to comment Share on other sites More sharing options...
Joespeeder Posted December 19, 2017 Share Posted December 19, 2017 Hey Jon, Here are the shots of the Russian Storch.... lol I just wanted to see how the 300v fit into the ESM Mig 3 cowl. I couldn't get it all the way forward into the cowl but you can get a general idea. I will make some cardboard cutouts to see how the 360v might fit. If I could get the 360v in there without cutting the jowls out of the cowl it might be an option. The front edge of the blue tape is where the front of the firewall is inside the cowl. Either way I can see CA soaked cardstock duct work will be needed to feed cool air to the jugs. Joe Would be very cool to have you join us for some warbird flying over here. I keep saying I want to go to the Goodwood Fesivtal of Speed so my coming over there may be more of a reality. Hmmm... Edited By Joespeeder on 19/12/2017 18:30:17 Link to comment Share on other sites More sharing options...
Jon H Posted December 19, 2017 Author Share Posted December 19, 2017 that cowl really is a bucket! once the engine is in, you can open up those intakes on the side and use them for cooling air. Should work a treat. Goodwood is also a nice idea, I have been meaning to go for years. There are plenty of airshows around that time as well so have a look at those if you do make it over Link to comment Share on other sites More sharing options...
Joespeeder Posted December 19, 2017 Share Posted December 19, 2017 Hey Jon, Yup, those intakes will be cut open, and the rear of the intake "bumps" opened like the scale vents. Plus I'll open all the exhaust ports to vent the cowl out. I have several ideas so far and I'll post the details when I get there. I used card stock on the La5,following your lead by opening the exhaust tunnels plus I have holes in the bottom of the cowl due to the mufflers. The trick part on the La5 is the scoop I made on top of the cowl. The front inlet is structured to blow intake air down onto the engine but there is a divider inside the scoop that blocks off the rear of the scoop from incoming air. The rear of the scoop is open to the inside of the cowl and to the rear of the scoop creating a suction and drawing out air from the top of the cowl by the firewall. The inlets to the jugs are card stock all the past the center line of each jug with only about 1/8 - 1/4 inch max clearance forcing the air past the jugs in a very directed manner. Card stock is very easy to shape and once soaked with CA is very tough stuff. I'll do something along those lines on the Mig but it'll be a while as I have a D9 to build this winter and laser inventory should be up and running by the time I get to the Mig. Edited By Joespeeder on 19/12/2017 21:38:26 Link to comment Share on other sites More sharing options...
Jon H Posted December 19, 2017 Author Share Posted December 19, 2017 Aww that intake looks so cool Link to comment Share on other sites More sharing options...
John Stainforth Posted December 20, 2017 Share Posted December 20, 2017 Jon, Surely one should not move the thrust line very far from its designed position? John Link to comment Share on other sites More sharing options...
Jon H Posted December 20, 2017 Author Share Posted December 20, 2017 Posted by John Stainforth on 20/12/2017 21:29:33: Jon, Surely one should not move the thrust line very far from its designed position? John true, the red line on the fuselage should be about right. In truth though, a speed air isn't likely to care very much Link to comment Share on other sites More sharing options...
John Stainforth Posted December 20, 2017 Share Posted December 20, 2017 Steve, Many thanks with posting your really useful figures of your chicken hopper system. Just what I was looking for. I'm going to do some trials with similar set-ups on my engine test bed. Link to comment Share on other sites More sharing options...
Paul james 8 Posted December 23, 2017 Share Posted December 23, 2017 Posted by bert baker on 15/12/2017 22:33:47: Hi it has J11 0n engine lug as well as my initials The carb is broken it is a 150 do you still stock this carb Looks like an Irvine carb, you may find one of those if you look around. I fitted one to my Laser 75 as an upgrade from the ST. Link to comment Share on other sites More sharing options...
Jon H Posted December 23, 2017 Author Share Posted December 23, 2017 That is one of our own carbs that we have used since about 2006. easy to replace Link to comment Share on other sites More sharing options...
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