Roger Smith's Heating Apparatus

[SparkyLB]

I'm watching the 10-part "Hand Finishing" series of videos for the 50th or so time; something of which I can't seem to get enough.  Would the forum be so kind and tell me what the white honeycomb-looking mineral(?) is that he uses to protect his table from the heat of his torch? 

I know bricks would work fine, but I'm curious.  If it's available to me, I'm going to acquire some. 

I'm going to give hands a try. 

[nickelsilver]

I haven't seen the video but there used to be asbestos pads for torch work which were replaced by another mineral later on. He probably has an old school asbestos pad or modern equivalent.

[SparkyLB]

2 hours ago, nickelsilver said:

I haven't seen the video but there used to be asbestos pads for torch work which were replaced by another mineral later on. He probably has an old school asbestos pad or modern equivalent.

Thank you, nickelsilver. 

In case you're interested, it's at 50 seconds in.  Don't blame me if you become attached to these 10 short videos! 

[Marc]

Try this

or this

[nickelsilver]

12 hours ago, SparkyLB said:

Thank you, nickelsilver. 

In case you're interested, it's at 50 seconds in.  Don't blame me if you become attached to these 10 short videos! 

Hmm that just looks like some type of firebrick.

[m1ks]

Think you mean this.

https://www.hswalsh.com/product/honeycombe-soldering-board-135-x-95-x-12mm-ts111

You need to place it on a heat resistant surface if you're using a torch, it helps retain heat on the piece you're working on.

Be very careful as they're fragile and snap easily. (Very similar to those old ceramic elements that gas fires used back in the 70's

[rogart63]

Used that when i worked as a dental technician. As m1ks says it's a kind of ceramic stone or material. https://picclick.com/CERAMIC-BOARD-SOLDERING-HEAT-PLATE-JEWELRY-BENCH-6x6-190815239228.html

 

[WatchMaker]

Thanks @SparkyLB, I hadn't come across Roger Smith's videos but I've now bookmarked them!

[rodabod]

I liked how he heated a brass block to indirectly blue the hands. I also appreciated it when he admitted to not getting the colour correct on one of the hands. That’s always a bummer. I think you’d be more likely to get consistent heating by using brass filings, but the visibility is inferior compared to his method. 

[SparkyLB]

3 hours ago, rodabod said:

I liked how he heated a brass block to indirectly blue the hands. I also appreciated it when he admitted to not getting the colour correct on one of the hands. That’s always a bummer. I think you’d be more likely to get consistent heating by using brass filings, but the visibility is inferior compared to his method. 

Agreed, since is not as efficient holding onto heat as cast iron or copper; there's more of a gradient.  This would cause brass heated from one side to always be much hotter where the flame is.  I like how Roger never brings flame close to metal to be blued.  Seems that Roger Smith's intention is to move the piece about such that the finished product can be as uniform as possible.  He admits the improbability of bluing 3 hands identically.  It's a learned skill, but what isn't? 

As for the bed of shavings offering inferior visibility, this seems like a large part of the equation.  If you watch, the color starts on the bottom and rises quite fast to the top.  If embedded in shavings, one might very easily miss this transition. 

[rodabod]

One of my horology tutors used to blue steel over a naked flame. I can’t remember the correct term for it, but he was very good at it. The key is to be very gradual, so you sweep through quickly so that the colour doesn’t progress much at a time. 

[SparkyLB]

rodabod, was this done with butane torch? 

[rodabod]

From memory, it was a spirit lamp. 

[rodabod]

... but I don’t see why you couldn’t use a torch. I’m not aware of if the lack of oxygen affects the process in some way. 

[watchweasol]

I believe bluing of parts etc was done over a spirit lamp aka  Donald De Carles book , as its easier to control the process.  Some years ago I watched a TV programme on Roger Smith from his workshop on the Isle of Man  the  man is a Genius in the watch making world , Hand build chronometers brilliant.

As regards the heat pads  There used to be asbestos from storage heaters, the modern ones Fischer I believe use the ceramic pads so a source there if you are looking for some, but keep the asbestos bagged up and dampen before use. 

[Colditz]

You have probably sourced the material but heres my 3 pennies worth. I think it is  cordierite honeycomb block. We used this stuff in the metallurgy lab where I worked. Hope it helps.