I've always been fascinated by the things people do in their spare time when they can do exactly what they want to do. Men and sheds are a particularly fertile field. Women tend to do their thing in the comfort of the house.
I was delighted to see Andy's picture of the clock movement he has made.
It struck me that we could perhaps start a new topic devoted to spare time skill. So Andy starts it off and my contribution is this:
It's a small steam engine made from scratch and is based on the Stuart 5A but a longer stroke. One of these will drive a 14 foot boat with steam at 250psi. By the way, we don't like to call them models, it's exactly the same construction and materials as a full size engine, just smaller. So come on out there, let's hear about what you make in your spare time. I reckon we could be in for some surprises!
Stanley Challenger Graham
Barlick View stanley at barnoldswick.freeserve.co.uk
Posted - 01/01/2008 : 05:09
Good question and I had to go back for a think. Solid castings are never true and tend to distort when you take the skin off, a composite like that one can be even worse. My way is to get a good face on one side, turn it round and face the other side and see how it looks. If it's sprung again reverse it and true the other side. Eventually you'll get near enough. Then true the rim at the same setting, reverse it and set it up again on the clean face you have made and clean the rest off. At that stage you know you've got a fairly stable casting and if your setting up was right it's held central. That's the time to bore because you know the hole will be central to the rim beyond any doubt. If you bore and then set it up on a mandrel as the datum you allow error to creep in because if you turn it on the mandrel you are relying on the truth of the mandrel and your setting up. With a big casting like this you need to grab it firmly to stop chatter and you will almost certainly get it wrong. Bottom line is that if you bore at the same setting as the rim, it has got to be central.
Stanley Challenger Graham
Barlick View stanley at barnoldswick.freeserve.co.uk
Posted - 01/01/2008 : 11:16
I can see your logic, if the fly wheel is set up using the o.d, there is less chance of the mass being out of balance,, interestingly when i was a lad , Maiden's had a lathe with a 6ft. face plate, we used to machine C.I. rings about 4ft dia, the set up was exactly as yours, skim, and then reverse the part skim again, repeat untill the part is " naturally flat". a point here, when drilling a pre cast bore hole in C.I. mouldings, , we always used a flat bit, not a helical one, i was told on enquiring why, that the flat bit would create a more truer hole, with less tendency to follow the hole ?. Isn't it funny how the brain can think of things 55 years ago, but cannot remember what time i got home last night !!.
Tony
"You can only make as well as you can measure" Joseph Whitworth
Posted - 01/01/2008 : 21:32
Yes a flat bit does run true. They still use them for gun barrels. I have some three fluted drills long series for the same purpose but in practice, the boring tool takes out any slight variation and if you think about it is just doing the same job as a flat bit but only one cutting surface. Making the CI rings is a good example of where you get into trouble with a casting when the stresses come out. Best way if you want absolute truth is to finish turn, throw in the yard for six months and then true with a light skim with a surface grinder. Fell's used to do their lathe beds like that. Too much trouble nowadays.
Stanley Challenger Graham
Barlick View stanley at barnoldswick.freeserve.co.uk
Posted - 02/01/2008 : 10:44
In case any of the regulars are wondering..... No, I haven't gone off the shed, I had a bloody good clean-up yesterday and a rest in the afternoon with 'Land of the Pheroahs ' on TV. I've decided that apart from ordering the wood for the packing case I shall have a go at getting the case clock going in the front room. It hasn't run for about ten years....... I think I shall need Namdy Gigglepants in as a consultant......
Stanley Challenger Graham
Barlick View stanley at barnoldswick.freeserve.co.uk
Posted - 02/01/2008 : 12:12
Do what I did with my ancient grandfather clock. Buy a cheap quartz clock movement, make some cardboard hands to suit the clock face and super glue them to the movement hands. A battery driven silent Grandfather is always a topic of converstaion with visitors. You could go a little upmarket and get a radio controlled movement and have it second accurate too.
My wife keeps her knitting in the space where the pendulum used to swing.....
Posted - 02/01/2008 : 15:37
Of course, such heretical ideas are often considered worthy of burning at the stake.........
If its any consolation the original movement and pedulum are still within the case, just moved out of the way a little. So should at some future date someone decides it would be nice to restore it to a ticking, inaccurate, job creation scheme the bits are all there.
Posted - 02/01/2008 : 16:00
I am thoroughly glad to hear that you kept the original movement...
I had the pleasure of repairing one of those a long time ago. Repivoting bits in a clock is one of my favorite things...right up there with root canal.
The one good thing about working on a case clock is that it's BIG. Not too much of a nightmare to see and manipulate . Doing the same to a cucoo clock is an exercise in frustration without the specialized tools.
Posted - 02/01/2008 : 16:17
Here is the link to Stanley's Compound Engine Video, it is another big file and it would be better if it were YouTubed but I haven't got an account with them.
I'm wondering if Pluggy could work his magic again.
Posted - 02/01/2008 : 17:20
I'm on the case. I'm currently at my mum in laws who has Virgin Cable, the download wasn't too bad (faster than my own in fact) but the upload speed is pitiful (around 20K a second). This could take some time....
Posted - 02/01/2008 : 18:00
Thanks for putting the video up doc. Worth the wait while it downloaded. That was it running on about 50psi. We tried it at 80psi and it was awesome. Needs the load on it before it gets full pressure. (about 150psi on steam)
Pluggy, you've missed the point. I'm not doing the clock so it will tell the time, I'm doing it because it will sit there talking to me and saying thankyou Stanley for getting this 150 years old mechanism running again...... It's mastery of the machine, something I've been doing all my life.
Stanley Challenger Graham
Barlick View stanley at barnoldswick.freeserve.co.uk
Posted - 03/01/2008 : 06:35
Thanks for that Pluggy, makes it more accessible. The knock in the HP crank bearing annoys me but I shall be strong and ignore it! I ordered the 1/2" ply for the export crate, it will be with me next week. I also ordered a piece of veneer face ply for a baseboard for the compund and as soon as I have made and fitted that it goes in the front room as an ornament. As for battery driven grandfather clocks having novelty value, not if you have any respect for the original maker. If you want an economic reason, my clock in it's present condition is worth about £300, if it's a going concern you can more than double that. When Newton was offered the job of installing the Siberia engine in the Science Museum he refused to have anything to do with it as soon as he heard they were going to drive it with an electric motor. Years later they saw the light and it can now be run on steam.
Stanley Challenger Graham
Barlick View stanley at barnoldswick.freeserve.co.uk
Posted - 03/01/2008 : 12:06
Thanks for that Stanley (and Pluggy)
Just looked in, whiling the time away before a trip to the dentist. The sight and sound of the compound has quite cheered me up.
Don't worry about the knock, you built it, you know that you could soon sort it, if the need were there. I've got an old vinyl Transacord recording of a Thames river steamer with a Sissons triple engine. Doesn't sound sound so different to yours!
Shed culture
