PC.Vere

Just to report that as I am having some big problems with mobility (especially in the workshop) - this is causing me to reconsider any plans I may have had - I may even have to forget having a workshop altogether! Time will tell and I won't give up thinking ahead, so I'll put everything on the backburner for now and hope like hell that things improve dramatically!! Thanks to all you guys for all the replies and interest you have shown - no doubt I'll still be looking in on the forum now and then.

Yes Simon, well spotted - That makes everything suddenly become crystal clear! When we are looking at a disassembled engine, we tend (at least I did) to forget about the hardened steel liner (with teeth cut in) - this of course explains the neat cuts (not gouges) on both sides of the rod. I remember that the "Doonside" mills replicas (from Australia) had a steel pin located on the top edge of the case where the cylinder flange sat and this registered with a hole on the flange, cutting out the possibility of the cylinder ever rotating. There you go, I didn't know everything after all! I wouldn't even consider using it with a rod in that state. Don't think I'll be doing a lot for a while till I get this health "hiccup" resolved. Edited By PC.Vere on 28/11/2015 04:42:26

I feel that I need to say that my efforts have been somewhat curtailed by some unexpected health issues (which involves not being able to stand or move around in my workshop), this is due to a hip replacement of three and a half years going badly wrong) but which I had expected would keep me working for the duration! Nothing has been resolved as yet, but I'll continue to live in hope and I intend to carry on when that time comes!   Edited By PC.Vere on 27/11/2015 22:07:43

Thanks ED, everything is as you say and i guess that rod is history really, but luckily I have dug up a new rod which I purchased from England a few years ago and that will replace it. However, I may have to have a go at making one for this project (which is a bit slow at the moment, (due mainly to babysitting the grandchildren - also a touch of laziness as well!) - but I'll get there.

It's been a while since i last posted, but I have had to attend to some other areas of my life - still not completely sorted - maybe never will be! So, to keep the thread alive, - Starting to pick up on where I left off this week, weather is moving into spring and this year promises to be windy down here (El Nino winds) so I hope it will be suitable for casting. Have been practicing my pattern making and corebox making skills using wood. My efforts are not dedicated to the Mills of course, but I should be trying to do a good crankcase along with all my other stuff using the picture someone (Paul Jeffries I think) sent me from Ebay earlier as a good example of what I hope to achieve! I have found some suitable hi tensile steel for the crank and with a bit of luck, I'll also be able to use that for the cylinder sleeve as well. (quite possibly i'll have to do more than one of each as I can see some challenges looming with fits!). I have also decided to cast as many as 4 crankcases (co-joined) to make the most of a melt, it would be silly to light up the furnace to pour just one tiny crankcase- very uneconomical!, I also intend casting some larger stuff as well with the same melt. That's the plan anyway ............. hopefully sooner than later. Edited By PC.Vere on 15/10/2015 08:45:10 Edited By PC.Vere on 15/10/2015 08:50:11

Colin, I see by your avtar that you may have some interest in motorcycles. They first became a passion for me when I noticed that model aircraft engines very much resembled the motorcycle engines of the day. After owning around twenty (bikes) and now that I'm older and not fit to ride anymore, I have reverted to an interest in model aircraft engines (understanding more of how they work this time).

[ Posted by Colin Leighfield on 22/08/2015 17:46:38: PCV, in my book you're a hero. I wish I had the skill to do something like this. ] Thanks, but that observation on me is way out! Also,you don't know whether you have the ability or not, and the skill has to be learnt by everyone, but you won't know until you give it a serious try  -  Of course you do need to have a bit of passion about what you are trying to do though - got to be in, "boots and all"! That's what I'm doing and if it fails, so what? it will have been a lot of fun trying and I will have learnt a quite a few lessons on the way, - maybe I will look silly? - well, nobody here actually knows me anyway! Edited By PC.Vere on 23/08/2015 01:45:12 Edited By PC.Vere on 23/08/2015 01:47:17

Posted by Paul Jefferies on 22/08/2015 08:33:14: [I wholeheartedly applaud what you are doing however have you seen this on ebay.......? Paul ] Thanks Paul, - yes that one looks to be very good indeed and is a reasonable price too! It isn't exactly the same as the original, maybe better, I dunno! - I would actually like to have one........but....... I am not looking for anything ready made, nor do I expect this effort to be a show stopper or a masterpiece of engineering - in fact, I'm not actually looking for a Mills .75 as such - I do already have one! What I am trying to do is learn about casting and foundry technology, using the Mills .75 (I had one when I was a kid) as an objective to aim for, this will include all the machining involved as well - I am already reasonably proficient in machining It's not really the easiest project I could have taken on of course, mainly because of it's small size, but I do believe that I can do it and if someone can learn something from my mistakes (which no doubt I will make ) then I will be happy! Progress will be slow and perhaps a little intermittent, but please bear with me - this is not the only thing I will be casting, but possibly the smallest! I don't really have a sensible reason for actually doing this in the first place, however there is a (slightly crazy) reason for my putting it all on this forum to give me some incentive to see it through - ie by trying hard not to end up with egg on my face!     Edited By PC.Vere on 22/08/2015 11:10:42 Edited By PC.Vere on 22/08/2015 11:14:39

By the way, how can I remove photos, both from my album and also from my posts? I see the 'edit' button disappears soon after posting. There are a few photos which are more or less duplicates. I would prefer to have them removed in order not to hog too much space on the forum.........Thanks.

Having a bit of trouble posting all this but I'll get there Photos are self explanatory really but I'll talk it through:- Selection of NZ native timbers which I acquired, but I think the one I started with is 'Kauri' (as seen on the lathe) and it turns very nicely - You will see a seam down the middle as I made it up from two pieces glued together with PVA and a piece of paper - this allows it to be split easily in order to make the pattern in two halves. I have decided to use sand mixed with sodium silicate for the mould, this will make a more robust mould as everything is so small and I can't risk using "greensand" as previously as this is more prone to collapsing - this I don't want on such a small pattern. I have included a picture of the Co2 equipment for gassing the sand mixture to harden it. It's a 'Sodastream' charger for mineral water etc, and it is cheap to exchange cylinders at the supermarket, guess you have something similar in the UK. I also need to use a much smaller crucible and therefore will need a correspondingly smaller set of tongs. (crucible I intend to use in the photo), also a much taller 'plinth' in the furnace - both of these I will need to make as well ! The 'Vinamold is a vinyl rubber which can be melted and poured into a cavity, which when solidified can be removed and used as a pattern to make a resin corebox, this can be used to produce cores in the casting (again, I may decide to just machine most of it out, (we'll see). Must say it's all a new challenge to me, it may sometimes be difficult, but it's great fun nonetheless.

Then of course it could be a "composite" engine made up from left over bits and pieces someone had lying around in their workshop! - a 'Bitza' - might explain the undamaged crankcase ! - possibilities are endless!