JohnnyB Posted July 28, 2008 Share Posted July 28, 2008 Hiya Guys,Just a thought really, but would it be possible to start a Forum Topic under the heading of "Free Flight Models" as I've recently dug out a couple of old Keil Kraft kits,and, as yet I have'nt found a decent Forum to join. I'm quite sure that many R/C modellers out there probably tinker with F/F models from time to time and RCM&E covers the subject from time to time, especially some of the larger F/F flying events. Look forward to any comments you may have.John. Quote Link to comment Share on other sites More sharing options...
Former Member Posted July 28, 2008 Share Posted July 28, 2008 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
JohnnyB Posted July 29, 2008 Author Share Posted July 29, 2008 Hiya Guy's,Quite a few years ago, I bought one of the Irvine Mills .75's. Now I've never run it and its been kept in its box since new. But the other day I dug it out with some old Keil Kraft kits only to find it has completely gummed up.I've tried soaking it in WD40 but no luck. So, can anyone suggest how to safely free up this little motor?. Would soaking in neat petrol do the trick, perhaps?At the recent Wings and Wheels, I bought one of the new Boddo CS Mills .75s and was so impressed with it that I immeadiately sent off to David Boddington for another. Then, yesterday, my latest copy of RCM&E drops through the letter box and there's a long article covering the Boddo Mills .75. How very interesting.Look forward to hearing from you.John. Quote Link to comment Share on other sites More sharing options...
John Bunting Posted July 30, 2008 Share Posted July 30, 2008 John, I think the problem with gummed-up small diesels is that the piston-to-cylinder fit is so close that it is almost impossible for any thin fluid such as WD-40 or petrol to get between the two and soften the film of thickened old oil that is holding them together. I'm assuming that no corrosion has set in. My approach, for what it's worth, would be to apply some heat, for example by supporting the engine over a switched-on soldering iron or a light bulb, say 60 to 100 watts, taking care not to let the engine get much hotter than it would get during normal running. Fit a prop, so that you have something to turn the crankshaft with, and use a cloth or glove to hold the engine itself. Squirt in a bit of WD-40, then try to turn the shaft, first one way then the other, but don't force it! You just have to use your judgement about how much torque you can apply without doing any damage. Once you notice even the slightest movement, you've won. Keep the engine hot and just keep rocking the shaft, both ways, gradually increasing the movement. This has worked for me with a couple of seized-up engines, but maybe someone else will come up with other ideas. Good luck!As another point of interest to anyone who has a Mills .75 or other small diesel, Alex Whittaker mentions, in his article in RCM&E, that their plastic tanks were prone to getting lost or damaged. I had this problem some years ago, and finally found that some of the hollow mushroom-shaped polythene 'corks' that are used in sparkling wine bottles can be adapted as a tank. Of course it has to be the type that is closed at the bottom, and if you then cut off the larger top part, what is left is almost exactly the right diameter to fit the aluminium top plate from the original Mills tank. I've used the same method to replace a Mills 1.3 tank, but in that case using the cut-off bottom of a small plastic bottle that just happened to be the right size. Quote Link to comment Share on other sites More sharing options...
Former Member Posted July 30, 2008 Share Posted July 30, 2008 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Mike Rolls Posted July 30, 2008 Share Posted July 30, 2008 As a diesel user since 1951, despite many times needing to free one up I have never had to resort to heat . Provided that motor has been run, I have also never known a diesel to corrode internally; burnt diesel residue isn't the nasty substance that burnt glow fule can be for an engine's innards. The best fluid to use is diesel fuel. WD40 isn't much use in really gummed up cases because it evaporates. 3-in-1 oil or the like isn't much good because it it too think. Diesel fuel is even more able to creep into microscopic gaps than is WD40 or plain paraffin, and even if it doesn't free the motor up straight away it will start to dissove the gummed castor and will free it eventually. Just apply it everywhere you can - in the ports, behind the prop driver (if the driver can be removed easily, dribble fuel over the exposed end of the bearing), attach a prop and apply gentley torque. If you can't make it move without your hands hurting on the prop - apply more fuel and wait some more. Evntually it will move. It make take several applications and some patience, but it will work. I sold some of my old diesels on E-bay last year. None had been run for at least 10 years, some for more like 30. Just about every one was gummed solid and every one that was, was freed up just with applying diesel fuel. If it is a plain bearing motor, once it can be turned over, you can run it. If it has ball bearings, don't try running it straight away - there is a chance than solidified castor will still be sticking the balls together and cause them to skid and damage themselves when turned at high speed. With BB engines (and assuming you either lack the knowledge or the desire to dismantle them) simply soak everything in more fuel and keep gently turning it over. If the balls have been stuck you will actually feel them start to free up - to do so you rock the motor to and fro up to compression as you can't spin it over the way you could with a glow motor by removing the plug.HTHMike Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted July 30, 2008 Share Posted July 30, 2008 Stick it in a pan of boiling water for half an hour witha few drops of fairy liquid _ enough to keep a few bubbles visible _ Crude I know but won't do any harm & will probably work . Don't ask me how I know ! Quote Link to comment Share on other sites More sharing options...
Mike Rolls Posted July 30, 2008 Share Posted July 30, 2008 If you follow the boiling water routine - oil everything IMMEDIATELY afterwards or anything ferous has a high probability of rusting. If you must try such a method - detergent is a better killer of oil based crud - and even more likely to rust things.Mike Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted August 1, 2008 Share Posted August 1, 2008 Quote Link to comment Share on other sites More sharing options...
Mike Rolls Posted August 1, 2008 Share Posted August 1, 2008 Oh, and if you do use detergent in boiling water - don't stick your nose over the pan. I am assured (but haven't tested the assurance!) that the vapours can do nasty things to your nasal passages.Mike Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted August 1, 2008 Share Posted August 1, 2008 & my brain cell in my case Ithink! Quote Link to comment Share on other sites More sharing options...
Ed Kershaw Posted August 1, 2008 Share Posted August 1, 2008 John,These are lovely engines and rather rare. Unless you're determined to do it yourself, I'd just pop it in a box and send it to John Haytree. It'll come back like new. Just tell him it's brand new and you don't want it test run (unless you do, that is).Ed Quote Link to comment Share on other sites More sharing options...
JohnnyB Posted August 3, 2008 Author Share Posted August 3, 2008 Hiya Guy's,Firstly, Thankyou all for your various comments.Well, I've decided to try the method suggested by Mike. My engine is now completely submerged in Model Technics D1000 in a jar. If this fails then I'll try some of the other methods suggested.I'll keep you all informed how it goes.Many Thanks,John. Quote Link to comment Share on other sites More sharing options...
JohnnyB Posted August 14, 2008 Author Share Posted August 14, 2008 Great news - I've finally got the Mills all nicely freed up after the Big Soak. Works a treat.But, spent a big part of yesterday trying to get the little blighter to run consistently.............. The problem I'm having really is getting the neddle valve AND the compression settings in some sort of sync.Can anyone please suggest a good starting point for both the needle valve and compression settings. I'm currently trying with an 8X4 prop, and using Model Technics D1000 fuelCheers,John. Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted August 14, 2008 Share Posted August 14, 2008 Memories About 3 turns out on needle -Finger over intake -flick 2 or three times -prime through exhaust port(s) a couple of drops -turn over to push up contra piston if necessary -fick again & increase compression 'til it fires -repeat as necessary - once running reduce fuelow to run sweetly &/or increase compression til happy - Dont over do the compression bitSounds like a prescription doesn't it !Hope 'tis helpful .You get a "feel" for it eventually .PS if you "flood the cylinder -blow though the exhaust & try a fresh start -easier to do than explain believe me Back to my b----y batteries Quote Link to comment Share on other sites More sharing options...
Former Member Posted August 14, 2008 Share Posted August 14, 2008 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
JohnnyB Posted August 16, 2008 Author Share Posted August 16, 2008 SUCCESS.......... . Thanks to Myron and Eric particularly, for your great suggestions. I really persisted all yesterday afternoon, and as a result I think I can safely say that I've got that "diesel flick". Myron, I certainly see what you now mean by getting the "feel for it" when flicking it over.Such a great feeling to hear the little beauty running for the very first tme after so many years in a box. When I first got it out I thought it was all doom and gloom as it appeared all gummed up. Nows she's running a treat and I've learnt even more about this great hobby in the process..Right - enough wading through this great forum, I really must get on with one of these old Keil Kraft kits to go with this great little motor now. Sounds like a few more challenges ahead........Ron2 - I had a good look at the Replikit stand at the recent Cosford show and it was pure nostalgia. They have brought back so many of the "Old" balsa free flight kits with all the fiddly bits CNC'd for you.Certainly sounds like there's abit of a F/F revival going on.Thanks to you all for your help.John. Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted August 16, 2008 Share Posted August 16, 2008 Question " What do you you do if it runs out of tune "Answer " With a little bit of help from your friends"--------So glad we could HELP you. Quote Link to comment Share on other sites More sharing options...
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