Ernie Posted April 19, 2017 Share Posted April 19, 2017 Hi Guys, i wonder, does anyone have a Mills 75 to sell? Or what about a leccy set up to give the same power? ernie Quote Link to comment Share on other sites More sharing options...
Paul Jefferies Posted April 19, 2017 Share Posted April 19, 2017 They appear regularly on ebay and tend to go for around £70...... This one is currently on offer, it is not a particularly good one as the tank and original spinner nut are missing........ http://www.ebay.co.uk/itm/Mills-P75-Vintage-Model-Diesel-Engine-/152514832286?hash=item238297a79e:g:JPkAAOSw3ZRY9TXh Paul Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted April 19, 2017 Share Posted April 19, 2017 Earnie, what weight would the leccy fly? Normal sports models are calculated at 100 watts per lb for motor choice At 1cc, the Mills would be approx 70W Dependent on prop selection and if run in We need your model description and weight to match up the electrics Quote Link to comment Share on other sites More sharing options...
Ernie Posted April 19, 2017 Author Share Posted April 19, 2017 Paul and Denis Thanks for that........I'm a big bike racing fan, and the Giro d'Italia starts early May. The afficionados among you will understand that it lasts for three weeks, so a lot of time in front of the tele. I'm getting there,....... So that all that time is not totally wasted, I like to have a wee project that I can build on a board on my knee Aeons ago, I was a huge keil kraft fan,so for a wee nostalgia trip, I thought i'd build a Slicker Mite from a set of laser cut bits. The span is 32 inches, but I can't find a weight. The recommended power plant is a mills 75, hence the queries I do like these tiny models, they certainly demand quite a bit of skill to build, especially saving weignt, and getting a half decent finish ernie Quote Link to comment Share on other sites More sharing options...
PatMc Posted April 19, 2017 Share Posted April 19, 2017 The Mills 75 power varied between quite a lot between individual engines, you could reckon on around .06 bhp @ 11,000 rpm as about average. However rpm would be with a 6" prop whereas mostly a 7" would be used, dropping the rpm to 9 - 10,000 & the power to around .05 bhp. In electric terms that between 37W & 45W. Forget about the 100W/lb "rule" that should be plenty of power for a Slicker Mite. I've flown a vintage APS Frankenstien design using a brushed motor with 9.6v nimhs @ 30W/lb & still been able to do loops & rolls with a Flycam2 attached. Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted April 19, 2017 Share Posted April 19, 2017 I used a Mills p75 in a Vic Smeed Mamselle with two channel radio and that had plenty of power and had to be de-compressed or it was too fast. Indian copies can vary enormously and a few just wont start. so beware of any "as new " examples . The Irvine Mills is a far more powerful engine and is heavier. Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted April 19, 2017 Share Posted April 19, 2017 When I started I am sure a recommended prop size for the Mills .75 was 8x4. That is what I used and the engine swung it no problem. Easier starting than a 7x4 as well, not that a Mills was ever hard to start! I seem to remember reading somewhere that engine tests on original Mills engines gave peak power readings between 0.47 and over 0.07 bhp! Whatever, they always gave enough. Quote Link to comment Share on other sites More sharing options...
PatMc Posted April 19, 2017 Share Posted April 19, 2017 Copy of tests for Mills .75 & 1.3 here. Quote Link to comment Share on other sites More sharing options...
Ernie Posted April 19, 2017 Author Share Posted April 19, 2017 WOW, thanks thats certainly enough to both get both inspired and up and running ernie Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted April 19, 2017 Share Posted April 19, 2017 I remember that article and it's probably the one that initiated the comments I made in my previous post about varying power outputs. As well as a genuine original .75 fitted in a Doug McHard "Wee Snifter"' I have an Indian version that I'm not very impressed with. I have an Irvine built 1.3 and an Indian 1.3, neither of which I have run yet. I've got a beautiful .4 version of the .75, earmarked for a particular project and one of the Boddington Mills twins made by CS. I had a disaster with that, causing the rear con-rod to bend. I have a replacement rod, but haven't got round to fitting it yet. I will one day. You might gather that the first .75 I bought for five shillings in around 1960 made a big impression. It was battered and the mounting lug on one side of the crankcase was bust, but it ran like a dream. I wish that I hadn't eventually given it to someone I can't remember now. Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted April 20, 2017 Share Posted April 20, 2017 It is perhaps worth mentioning that the Mills 75 was at the time the "slow fly" of diesels. Nobody bought it for its power output (you would get an AM 10 for that!) but it could turn big props (8x4 or 7x6) relatively slowly the resulting gain in propulsive efficiency off setting its modest output. On this basis a 120W 1500kV out runner on a 3s would easily match a Mills 75 even taking into account the weight of the LiPo. Quote Link to comment Share on other sites More sharing options...
Paul Jefferies Posted April 20, 2017 Share Posted April 20, 2017 There is no substitute for the smell of diesel fuel and castor oil all over your model, I'm afraid leccy just isn't the same....... I suppose it depends on why you want to build your Slicker Mite, you pays your money and you takes your choice but if you want the "full experience" it simply has to be a Mills. Paul Quote Link to comment Share on other sites More sharing options...
Ernie Posted April 20, 2017 Author Share Posted April 20, 2017 Good morning It still seems like a good idea, and I certainly need a giro project, but on profound reflection, The wee slicker was designed to go skywards like a bat out of the hot place, and glide down ever so gently. Not the ideal sports model, but I do like the kinky outline Pause for profound thought ernie Quote Link to comment Share on other sites More sharing options...
Andy Green Posted April 20, 2017 Share Posted April 20, 2017 Hi Ernie Have pm'd you. Andy Quote Link to comment Share on other sites More sharing options...
PatMc Posted April 20, 2017 Share Posted April 20, 2017 Posted by Simon Chaddock on 20/04/2017 01:26:29: It is perhaps worth mentioning that the Mills 75 was at the time the "slow fly" of diesels. Nobody bought it for its power output (you would get an AM 10 for that!) but it could turn big props (8x4 or 7x6) relatively slowly the resulting gain in propulsive efficiency off setting its modest output. On this basis a 120W 1500kV out runner on a 3s would easily match a Mills 75 even taking into account the weight of the LiPo. Simon, 120W is about the power of an AM15, the Mills would be putting out around 1/3 of that on a 7x4 which is probably the best match prop size to give the Slicker Mite a fast climb. Quote Link to comment Share on other sites More sharing options...
PatMc Posted April 20, 2017 Share Posted April 20, 2017 Posted by Ernie on 20/04/2017 08:25:52: Good morning It still seems like a good idea, and I certainly need a giro project, but on profound reflection, The wee slicker was designed to go skywards like a bat out of the hot place, and glide down ever so gently. Not the ideal sports model, but I do like the kinky outline Pause for profound thought ernie Ernie, I think the climb from launch would have been fairly fast but in relative terms nothing like a modern FF duration power model or even what we've come to expect from most modern E-gliders. BTW the Mite pre-dates the Mills .75 the plan shows an Amco .87 which was about the same power. Dunno how you were supposed to adjust the compression in the limited space under the wing/pylon LE. Quote Link to comment Share on other sites More sharing options...
Former Member Posted April 21, 2017 Share Posted April 21, 2017 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
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