dave parnham Posted June 13, 2019 Share Posted June 13, 2019 Sorry Chris but this has been built for sometime just never got round to final fitting out. Top wing needs covering and to be honest I'm thinking of recovering the whole thing coz of my terrible paint job. The build stalled when it came to soldering up the N struts as my soldering skills weren't good. Link to comment Share on other sites More sharing options...
Alan Hilton Posted June 13, 2019 Share Posted June 13, 2019 Hi Jon Im currently making a back plate mount for my 180 .Do you see a problem with this? Regards Alan Link to comment Share on other sites More sharing options...
Jon H Posted June 13, 2019 Author Share Posted June 13, 2019 nah. i mounted the 180 in my stampe that way. The only down side is that the thing is totally rigid in it mounting so any/all vibration is transmitted straight to the model. Nylon mounts have a degree of flexibility and reduce this somewhat. Its not the end of the world, just something to be aware of Link to comment Share on other sites More sharing options...
Don Fry Posted June 21, 2019 Share Posted June 21, 2019 Posted by Don Fry on 28/05/2019 16:30:56: Re 'o' rings, I have just replaced the original carb main needle ring on a well used 80, 2009 vintage. Cause of failure was abrasion damage, as its new home was a cowled machine where the needle comes out to remove the cowl and I did it dry. Quite a few times. Dunno what the new one is made of. And I've just come from the field an the newly fitted o ring is failing, made of cardboard I expect. Jon, what is the size, material of these things, I'll get a packet. Link to comment Share on other sites More sharing options...
Jon H Posted June 21, 2019 Author Share Posted June 21, 2019 Can you post a photo of the offending item? If its the one i think it is then it should be BS005..or perhaps 004 in NBR70 material. 005 and 004 are the two sizes we use for the slow run and main needle but i cant recall which is which off the top of my head. Its also friday afternoon and the cider is out so that might not be helping :D Edited By Jon - Laser Engines on 21/06/2019 17:15:01 Link to comment Share on other sites More sharing options...
Martin McIntosh Posted June 21, 2019 Share Posted June 21, 2019 Hi Jon, I took my new Spit. up again today hoping that I had sorted out the problems regarding cg and retracts, prior to taking it to W&W. Looks like I have the thrust line wrong since it climbs like hell on full power then if trimmed for such it similarly dives when on idle. Question is, I think that I bought a 180 size mount from you for the original and do you have another which you could bring next weekend? I need one to modify in order to keep the spinner central. Tried to phone just after lunch but forgot that you were not there. Will have to put the motor back into the old model for the event. Link to comment Share on other sites More sharing options...
Chris Walby Posted June 22, 2019 Share Posted June 22, 2019 Martin, I can't really speak from experience, but picking up info from the SG Hurricane thread and Jon's comments I was not expecting mine (Hurricane) to be anything but throttle/pitch sensitive. I am sure Jon advised me to trim at around 1/2 throttle for level flight and use the elevator for other settings. I appreciate if its really bad it might need adjusting. Good luck wit the Spit and let us know how you get on Link to comment Share on other sites More sharing options...
Martin McIntosh Posted June 22, 2019 Share Posted June 22, 2019 Hi Chris, This is now my 4th Spit. and none of the others or my two Hurricanes exhibit this trait. It is supposedly identical to my other 72" one apart from the lighter weight. I have decided to give it one more try, this time with throttle mixed to elevator (switched mix in case I have it all wrong since I have had to guess at the various mix points). Will probably have to wait until tomorrow because of a forecast unflyable wind direction today. Link to comment Share on other sites More sharing options...
Jon H Posted June 22, 2019 Author Share Posted June 22, 2019 I dont think i have any mounts at the moment but i will check on monday. As Chris suggests, if trimmed for a half throttle cruise does the model change trim with power alone or is it air speed related? My P39 is very airspeed sensitive just as Chris's Hurricane will be. Im not sure how those spits behave, i assume its different to your previous example? If the weather is decent tomorrow i will probably fly, we can look at it on the field if you like Link to comment Share on other sites More sharing options...
Martin McIntosh Posted June 22, 2019 Share Posted June 22, 2019 It is the moment of increasing or decreasing the power that shows this up before the model has time to change speed. We shall see tomorrow if my temporary fix works. Link to comment Share on other sites More sharing options...
Jon H Posted June 22, 2019 Author Share Posted June 22, 2019 Posted by Martin McIntosh on 22/06/2019 10:37:55: It is the moment of increasing or decreasing the power that shows this up before the model has time to change speed. We shall see tomorrow if my temporary fix works. ahh fair enough. what time are you heading up? Link to comment Share on other sites More sharing options...
Martin McIntosh Posted June 22, 2019 Share Posted June 22, 2019 Elevenish probably. Link to comment Share on other sites More sharing options...
Don Fry Posted June 23, 2019 Share Posted June 23, 2019 Posted by Jon - Laser Engines on 21/06/2019 17:14:35: Can you post a photo of the offending item? If its the one i think it is then it should be BS005..or perhaps 004 in NBR70 material. 005 and 004 are the two sizes we use for the slow run and main needle but i cant recall which is which off the top of my head. Its also friday afternoon and the cider is out so that might not be helping :D Edited By Jon - Laser Engines on 21/06/2019 17:15:01 Jon, I've just got the needle out, and can't see any damage to the O ring, even under a REALY good illuminated magnifier. It looks a good fit, and the seats are clean and good. Therefore I conclude, my leak is a drip from the Venturi, and my problem lies elsewhere. If you can remember when in work to look up the number of the ring that would be great. The downside of jumping to conclusions without evidence. Time to get down to sorting this aircraft properly, cowl off, as I'm getting frustrated with it. edit. And first I measured what I have fitted. It is NBR 70, but a metric size, and is not the same as as the rings you quote. No point in proceeding further until I am happy the engine is as spec. Edited By Don Fry on 23/06/2019 11:37:37 Link to comment Share on other sites More sharing options...
Jon H Posted June 24, 2019 Author Share Posted June 24, 2019 Hi Don It is a bs005 on the needle and its an imperial size apparently. If the O ring is ok though fuel dripping from the carb is usually tank position as it will obviously gravity feed out if the tank is too high. If you need any O rings let me know Link to comment Share on other sites More sharing options...
Olav Sivertsen 2 Posted June 24, 2019 Share Posted June 24, 2019 Hi.I am fitting a Laser 70 in my Tiger moth inverted ,does it matter which way up the carburettor is positioned ie-needle valve at the top or at the bottom.? Thanks. Link to comment Share on other sites More sharing options...
Jon H Posted June 24, 2019 Author Share Posted June 24, 2019 Posted by Olav Sivertsen 2 on 24/06/2019 08:52:41: Hi.I am fitting a Laser 70 in my Tiger moth inverted ,does it matter which way up the carburettor is positioned ie-needle valve at the top or at the bottom.? Thanks. nope, the carb can point in any direction. As long as the tank is where it needs to be (the fuselage floor most likely) you will be just fine. Link to comment Share on other sites More sharing options...
Don Fry Posted June 24, 2019 Share Posted June 24, 2019 Thank you John. Now I know the size I can source locally. Link to comment Share on other sites More sharing options...
Alan Hilton Posted June 25, 2019 Share Posted June 25, 2019 Hi Jon what sort of duration would I get out of a 180 in a ww1 model on a 14 oz tank Alan Link to comment Share on other sites More sharing options...
Jon H Posted June 25, 2019 Author Share Posted June 25, 2019 depends on prop/tuning/throttle... I have a 14oz in my stampe and on glow with a 20x6 i could easily fly 10 minutes and have a reserve. How much that reserve was i dont know as i never measured it. Im sure i flew near 15 minutes once before landing and still had some left. In any case, you should be very safe for 10 minutes at half throttle with the occasional burst to full chat for a loop/wing over. As the stampe is more aerobatic than most WWI aircraft you will likely use less fuel than i did 'throwing' the stampe around. Its not a perfect test but if you fire it up with your chosen tank and run it for 5 minutes at just over half throttle. After that turn it off and see how you made out. I usually do this on maiden flights. Timer for 5, land, measure what is left and modify the timer accordingly. Link to comment Share on other sites More sharing options...
Alan Hilton Posted June 25, 2019 Share Posted June 25, 2019 Thanks Jon Just the response I needed it’s an se5a and I’m using a 20 x6 prop Alan Link to comment Share on other sites More sharing options...
Jon H Posted June 25, 2019 Author Share Posted June 25, 2019 It should be fine. I look forward to a video Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted July 15, 2019 Share Posted July 15, 2019 Just reading the last couple of posts for large slow biplanes with a 180 using a 20 x 6 prop, I have just acquired a Mick Reeves 1/4 scale Camel with a 200v , it's currently fitted with a Graupner 16 x 8, would a 20 x 6 be more appropriate, I have a wood Powermax 20 x 6 I could try. Edited By Frank Skilbeck on 15/07/2019 15:44:28 Link to comment Share on other sites More sharing options...
Former Member Posted July 15, 2019 Share Posted July 15, 2019 [This posting has been removed] Link to comment Share on other sites More sharing options...
Alan Hilton Posted July 15, 2019 Share Posted July 15, 2019 Hi Frank I have db 1/4 scale pup with a 200 v twin a 20x 6 prop is ideal Alan Link to comment Share on other sites More sharing options...
Jon H Posted July 15, 2019 Author Share Posted July 15, 2019 yup, 20x6 at least. 16x8 is too small even for an aerobatic model. It will do over 10k in the air on that prop! I found a 22x6 at wings n wheels last year and the 200v will just swing it. Revs are low, but it would be ok in a pup and i will probably use it on mine when i eventually get it built. 20 and 21x6 are totally safe. Link to comment Share on other sites More sharing options...
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