Parslow's Skeleton Clock by Raynerd

[raynerd]

Many thanks to everyone who has taken the time to reply and great to see so much support for using the CNC. I must admit, it did get me thinking...if the gaps between teeth are 0.92mm, without  checking im pretty sure it is, and you can get end mills right down to stupidly small sizes, in theory, could the entire wheel be cut via CNC!! Anyway, thoughts for another day...

John, John, mick and Rob, thanks for the message and support in using the CNC. Funnily enough I'm always shocked with the amount of CNC work in these so called hand build watches. I was watching a YouTube video of the apprentice of the late George Daniels, and even his expensive "hand built" watches used many CNC cut parts and pieces!

Alan,I did think of s spokes but in my opinion, was worried that would look a little OTT. Although I've used modern CNC, I like the traditional straight cross outs.

VTsteam... Well worth cobbling one together. I've not tested my runout lately but it was pretty damn good last time I put it together and it is bloody hurtling around a some speed, 14,000rpm according to mach3 and home brew tachometer. All that on some standard skate board bearings. To be honest, with the new power supply showing that this is clearly a useful and functional spindle,  I'd be tempted to now upgrade the bearings. The only warning people keep telling me about with these outrunner motors. Is them running too hot but I've to experienced this at all. Certainly no where I can feel anyway.

NickG - yes very satisfying, I was pleased that my CNC could accurately cut wood and drag engrave metAl. However, with the new power supply on the spindle, I can actually cut brass which has just pushed the mAchine into a whole new level of usefulness for me!! I mad the machine using 1/2 ally plate and steel supports, with the x axis running on 2 steel bar support slides AND a more expensive steel brace and linear bearing. The entire machine is mounted on be large .5" ally plate bed, so for such a small machine the thing is pretty rigid. I've always been confident it could do useful work if I found a small enough but rigid enough spindle to match,

Stew - thanks for replying. You were a real inspiration a few years back now when you took the time and effort in trying to make a clock wheel with me. I've never really stopped trying since then!

And finally one of the wheels cleaned up a bit...

[Alan Haisley]

Many thanks to everyone who has taken the time to reply and great to see so much support for using the CNC. I must admit, it did get me thinking...if the gaps between teeth are 0.92mm, without  checking im pretty sure it is, and you can get end mills right down to stupidly small sizes, in theory, could the entire wheel be cut via CNC!! Anyway, thoughts for another day...

Or at least you could gash the teeth and really reduce what the gear cutter needs to do. 
Alan

[Brass_Machine]

So there it is...I've cheated and used CNC but hey ho...I built the CNC machine itself so that surely that scores me some points back!?!? 

The use of CNC on this board should never be considered "cheating".

Eric

[raynerd]

  still here!

Did a bit more tonight. I wanted to make the mainspring barrel but after my disaster last time I was worried about making such a thick wheel again. I have been lucky to borrow a Thornton cutter, not because the home made one was dud, just because I spoilt it when I slipped on the last cut.

I was also struggling for suitable thick brass tube until my pal suggested an old barrel and cut the wheel off! I dug out an old mainspring barrel with snapped teeth:



Cut off the wheel and cleaned it up:




I then cut the groove in my wheel to match the barrel:






The plans say to silver solder the two together or soft solder. I would prefer to silver solder but I'll need to get it really hot and will the brass discolour and need a lot of working in polishing it back up....especially in areas I can't even get to???  Any thoughts?

Chris

[andyf]

The plans say to silver solder the two together or soft solder. I would prefer to silver solder but I'll need to get it really hot and will the brass discolour and need a lot of working in polishing it back up....especially in areas I can't even get to???  Any thoughts?

Having regard to the quote below, which appeared on another forum yesterday, it looks like you need the lowest melting point you can get if using silver solder, and aim the flame down into the barrel. Those teeth might heat up a bit quickly if the flame gets on them.

Andy

Quote:
".....turns out that you can heat Brass parts too much... found a nice spring clamp to hold the parts I was soldering next, got everything clean and fluxed up, poured the heat on and soldered nicely - when everything was cool I pulled the spring clamp off to find that it had sunk into the brass by about 2mm!"

[Meldonmech]

Hi Chris,
              It is looking good, clock makers of the past did not use tube for drive barrels. They used 1/8 inch strip, annealed  and formed into a barrel, silver soldered at the joint. The barrel end was then sweated on using soft solder.  I have used this method on all my clocks, and have have not encountered a single problem. This method has been used for hundreds of years.
                                                      On one of your pictures I noted a small chamfer on the wheel crossings, the normal convention in clock making is to leave the crossings with sharp edges.

                                                                                              Well Done          Cheers David

[ddkhalaji]

The plans say to silver solder the two together or soft solder. I would prefer to silver solder but I'll need to get it really hot and will the brass discolour and need a lot of working in polishing it back up....especially in areas I can't even get to???  Any thoughts?

Chris

If you are worried about the temperature, have you tried using "easy" silver solder, which has the lowest melting temperature of around 650 C, "hard" silver solder usually melts around 750 C. Is the brass actually discoloured? I know a lot of the hard black scale is usually flux, and it will blunt a file in a short amount of time. Therefore the part is placed in a 'pickle' (diluted sulphuric acid) afterwards for several seconds, and then washed to remove all traces of the acid. Once dry, the part should be reasonable in appearance, and shouldn't need a lot of polishing.

I'm unsure how familiar you are with silver soldering brass, sorry if these are the steps you have already taken. Then I assume it would be practice getting the balance right between your flux, solder and temperature.

Dean

[NickG]

Looks v professional that Chris. If you pickle the parts after in sulphuric acid you can usually clean them up pretty well.

[S. Heslop]

I see no cheating Chris , you used the tools available to you ,a tool you built  , Those that think CNC is cheating don't understand CNC , they just think its just a case of press the button marked "cross out clock wheels "  and out the part pops    ,  they be the same folk that think nothing of buying a set of castings .

I remember a few years ago CNC machines were all the rage with a certain type of person. I think they all fully expected them to be just like that, and were disappointed when they realised how much work they really were.

Now they've all moved onto 3d printers expecting the same.


Those gears are looking real swish though. Can't wait to see the clock start to take shape.

[vtsteam]

Looks really nice!

Tools are tools. CNC is like a hammer. A lot of potential, but just a hammer on its own. not a birdhouse.

I have a couple of CNC machines, but I find it more fun and easier to act than think these days. Unfortunately.