Hrcoleman66
Active Member
- Joined
- Aug 10, 2014
- Messages
- 44
- Reaction score
- 8
Hello all,
Over in my introduction in the welcome section, I talked about the engine I have in mind.
From Scrap Brass and and odds and ends, I was intending to do a single cylinder double acting horizontal mill engine with a 1/2" bore and a 3/4" stroke.
The cylinder was and still is a simple cylinder 22mm in dia (about 7/8") which will then have a flat milled in the side to take the Valve face which will be a simple flat block soldered in place. The Steam Chest and cover will then be secured by means of studs and nuts.
Way back when I was an fitter and turner, the thought never occurred to me to construct a cylinder this way. This was pre-internet days you understand... and all my knowledge at the time was gleaned from a reprint on Muncaster that I picked up from the Technical Bookshop in Melbourne. And that dealt purely with castings.
The only question that remained for me was whether to do the cross head as a slide type (like on the Stuart S50 and the Victoria) or a cylindrical type (Like on the Stuart 10H).
Last Saturday, however, I was on my way back from the my flying clubs (I also dabble in RC Aircraft) field and passed an antique shop that I new had some old Mamod stuff in the past.
There I happened on a Bronze flywheel casting a little over 100mm in diameter... A bit rough, but it has potential.
Friday I spent fitting my four jaw chuck to my lathe - I must explain here - The Lathe is a Haffco type I purchased from Hare and Forbes in Melbourne a couple of years ago... and the four jaw they sold me to suit it didn't actually... suit it that is. The lathe takes an 80mm chuck (the type with the 55mm recess that locates on the boss on the chuck plate) and the four jaw is a 100mm job that just is not meant to go there. Being a 100mm chuck though, I can see great advantages in that extra 20mm and decided to spend a few hours turning the rear face to match it with my lathes chuck plate.
That job done, I swapped back to the three jaw and turned up the cylinder blank, turning the OD and then facing and drilling and boring the bore and then lopping that off with a hacksaw and turning up a mandrel from Aluminium scrap in order to face off the other end.
Then it was over to my brand new Micro Mill to mill the flat to take the valve face.
That done, I need now to find some suitable brass flat to use to make the valve face and steam chest...
In the mean time, The Bronze Flywheel casting was chucked up and I started to clean it up.
In the end, I reckon it's going to come out at about 98mm diameter, the rim ending up about 10 - 12mm wide by about 3mm thick. It has 6 spokes that will clean up OK.
But as I cleaned it up (I haven't machined raw bronze castings in the past... hard on HSS tool bits... I may have to invest in some carbide tips and holders), it started to look more and more like it would suit an engine similar to a Stuart Victoria or even... a Twin Victoria (or at least, my downsized interpretation)!
So, to cut a long story short, that has decided my Cross Head Type. Sliding it is.
I'll arrange some photos soon I hope.
Cheers,
Hugh
Over in my introduction in the welcome section, I talked about the engine I have in mind.
From Scrap Brass and and odds and ends, I was intending to do a single cylinder double acting horizontal mill engine with a 1/2" bore and a 3/4" stroke.
The cylinder was and still is a simple cylinder 22mm in dia (about 7/8") which will then have a flat milled in the side to take the Valve face which will be a simple flat block soldered in place. The Steam Chest and cover will then be secured by means of studs and nuts.
Way back when I was an fitter and turner, the thought never occurred to me to construct a cylinder this way. This was pre-internet days you understand... and all my knowledge at the time was gleaned from a reprint on Muncaster that I picked up from the Technical Bookshop in Melbourne. And that dealt purely with castings.
The only question that remained for me was whether to do the cross head as a slide type (like on the Stuart S50 and the Victoria) or a cylindrical type (Like on the Stuart 10H).
Last Saturday, however, I was on my way back from the my flying clubs (I also dabble in RC Aircraft) field and passed an antique shop that I new had some old Mamod stuff in the past.
There I happened on a Bronze flywheel casting a little over 100mm in diameter... A bit rough, but it has potential.
Friday I spent fitting my four jaw chuck to my lathe - I must explain here - The Lathe is a Haffco type I purchased from Hare and Forbes in Melbourne a couple of years ago... and the four jaw they sold me to suit it didn't actually... suit it that is. The lathe takes an 80mm chuck (the type with the 55mm recess that locates on the boss on the chuck plate) and the four jaw is a 100mm job that just is not meant to go there. Being a 100mm chuck though, I can see great advantages in that extra 20mm and decided to spend a few hours turning the rear face to match it with my lathes chuck plate.
That job done, I swapped back to the three jaw and turned up the cylinder blank, turning the OD and then facing and drilling and boring the bore and then lopping that off with a hacksaw and turning up a mandrel from Aluminium scrap in order to face off the other end.
Then it was over to my brand new Micro Mill to mill the flat to take the valve face.
That done, I need now to find some suitable brass flat to use to make the valve face and steam chest...
In the mean time, The Bronze Flywheel casting was chucked up and I started to clean it up.
In the end, I reckon it's going to come out at about 98mm diameter, the rim ending up about 10 - 12mm wide by about 3mm thick. It has 6 spokes that will clean up OK.
But as I cleaned it up (I haven't machined raw bronze castings in the past... hard on HSS tool bits... I may have to invest in some carbide tips and holders), it started to look more and more like it would suit an engine similar to a Stuart Victoria or even... a Twin Victoria (or at least, my downsized interpretation)!
So, to cut a long story short, that has decided my Cross Head Type. Sliding it is.
I'll arrange some photos soon I hope.
Cheers,
Hugh
