It’s been a while since I updated the blog, mostly because not much has happened recently. Well, plenty of thinking but it’s hard to take a photo of that! Bob has been busy drawing Issue 2 of the plans, which I now have scanned in.
Graham has been on holiday so we can’t access the engine, and we haven’t finished making a new spanner yet anyway. On that, Nick has been busy with his rotary table as we’re planning to make the next spanner a different way.
I’ve been holding off spending big money until I know I can get all the parts, but I figured £40 for some 6082 aluminium to make a conrod was ok. Nick was planning to make the outside on his machine, but research into cutting speeds has lead us to abandon that idea.
Back to old school millers in Bob’s shed then! Luckily Nick has done some homework and worked out how we can do this. What a clever bloke! I’ll be taking these calculations round to Bob’s later.
A morning at the airfield saw the Spanner used in anger. It worked a treat! We could only get at 4 nuts on the whole engine due to the tightness of space. I think spanner mk II will be slightly different, remade from guage plate so it can be hardened.
Looking at the "Good" engine was hard work. Everything is very tightly packed, like a Chinese puzzle where each part requires removal of the next to get it off. We managed to get a couple of manifolds off and peered inside. The sleeves we could see were rusty, not a good sign. We might only salvage a piston and ball joint, but we’ll see.
Graham has a couple of weeks holiday now, so we have time to remake the Spanner. I might get some alloy so we can start to make the conrod too. Nick is ploughing on with his coreXY plotter robot, and Bob is finalising issue 2 of the design.
I’ll return the nut we borrowed and research the CNC plasma cutter in more detail.
I went back up to Donnington tonight to check out Graham’s other engine. It wasn’t what I expected but it has potential. It also gave me chance to try out the new spanner. (Which fits the nuts but is too big, so a little adjustment is required).
It looks dry and with all the manifolds intact, so the internals may be OK. The manifolds will take a lot of time to remove, which is Saturday’s job. Another trip planned with Bob and Nick then! I’m lucky to have some good friends around to help out!
Mr Nick proudly showing the final item. I will research whether it’s worth hardening it before we head off to the airfield.
Lining up a treat, you can see the dowels in action.
I went round to see my mate Nick today, armed with some 6mm steel plate left over from the workbench. The idea was to make a spanner by cutting the same profile as the prototype in steel.
The issue we had was the cutting depth of the small diameter cutters. We had to cut half way through, then turn the job over and do the same from the other side. We also had to make sure that the two sides lined up perfectly.
Nick made a jig to hold the job between two dowels along the centre line, so when we turned it over everything would line up. It worked perfectly! I’m really seeing the benefit of CNC machining and I think as I tool up that’s the way I’ll go.
Here’s the master at work.