Reference for brushing & finishing patterns (sunburst, snail, circular, etc)

[mbwatch]

Can anyone recommend a reference for techniques on achieving some of the common classic finishing techniques as found on larger flat surfaces like ratchet wheels? I am referring to patterns like circular grain, sunburst, snail, etc.

The circular grain is fairly obvious - make a polished part spin and draw an abrasive from the center outward. At the moment, I would like to restore a sunburst surface on a ratchet wheel that someone (I won't say who) scratched while attempting to unwind a mainspring with a screwdriver due to a broken stem. I have plenty of parts to practice on, but I can't find the watchmaking technique to dig out through all the internet noise of sunburst guitar finishing.

Even if anyone can just give a general description like "polish the part, rotate at high or low speed while drawing an abrasive outward/inward/across/around/whatever" - I would appreciate that starting point. But I'd also love to know if there's a preferred old book.

This NOMOS video shows what I would know as a snail finish, with no narration. I'm looking instead for the type of finish with straight lines radiating out from the center. like

 

[Neverenoughwatches]

47 minutes ago, mbwatch said:

Can anyone recommend a reference for techniques on achieving some of the common classic finishing techniques as found on larger flat surfaces like ratchet wheels? I am referring to patterns like circular grain, sunburst, snail, etc.

The circular grain is fairly obvious - make a polished part spin and draw an abrasive from the center outward. At the moment, I would like to restore a sunburst surface on a ratchet wheel that someone (I won't say who) scratched while attempting to unwind a mainspring with a screwdriver due to a broken stem. I have plenty of parts to practice on, but I can't find the watchmaking technique to dig out through all the internet noise of sunburst guitar finishing.

Even if anyone can just give a general description like "polish the part, rotate at high or low speed while drawing an abrasive outward/inward/across/around/whatever" - I would appreciate that starting point. But I'd also love to know if there's a preferred old book.

This NOMOS video shows what I would know as a snail finish, with no narration. I'm looking instead for the type of finish with straight lines radiating out from the center. like

 

I remember talking about this sometime ago, not here though , i don't think . Sunburst graining...slow rotation of the wheel with lateral brushing.

[mbwatch]

2 hours ago, Neverenoughwatches said:

Sunburst graining...slow rotation of the wheel with lateral brushing.

Experimentation time then...

[tomh207]

The only reference I have is for snailing from Jendritzki’s lathe book if that’s of any help.

 

Tom

[mbwatch]

Well I made a horrific looking ratchet wheel, but the light does sort of reflect in sunburst. This was by gluing the wheel to a Dremel bit in my drill's lowest speed and touching it with 400 grit. My makeshift "lathe" (drill clamped in a vise) is a bit lacking in stability for this job and I'm probably going to need some better tools.

[tomh207]

At least you’re giving it a go. I think for this a lathe with wax chucks would be the best. For snailing a crosslide with either a milling attachment or something made to hold a Dremel or flex shaft.

Tom

[tomh207]

@mbwatch
Here is the short section in the above mentioned book. It’s not much but is clear and concise. I think that Eveflex grey(coarse) wheels would be worth trying for this.

Tom

Edited December 29, 2024 by tomh207

[mbwatch]

@tomh207 Thank you - the diagram adds crucial context to what was shown in the NOMOS finishing video. With the right tools this feels pretty achievable. (and yes you guys all got me lathe shopping now)

[Neverenoughwatches]

16 hours ago, mbwatch said:

Well I made a horrific looking ratchet wheel, but the light does sort of reflect in sunburst. This was by gluing the wheel to a Dremel bit in my drill's lowest speed and touching it with 400 grit. My makeshift "lathe" (drill clamped in a vise) is a bit lacking in stability for this job and I'm probably going to need some better tools.

I'm not quite sure on the process you used MB or maybe my description was poor. This is kinda what I was suggesting

[mbwatch]

40 minutes ago, Neverenoughwatches said:

I'm not quite sure on the process you used MB or maybe my description was poor. This is kinda what I was suggesting

Well, 1 rpm is definitely a lot slower than my drill's lowest speed, probably around 300 rpm. I ran 400 grit sandpaper across it at that speed and got a result that is shiny but nothing like the wheel I pictured in the original post.

May I ask what tool this is?

[Neverenoughwatches]

10 minutes ago, mbwatch said:

Well, 1 rpm is definitely a lot slower than my drill's lowest speed, probably around 300 rpm. I ran 400 grit sandpaper across it at that speed and got a result that is shiny but nothing like the wheel I pictured in the original post.

May I ask what tool this is?

Lol anything that can quickly revolve a small grinding wheel or wire wheel to form the engraving or graining ie. Dremel. The ratchet wheel could be set into any kind of jig that you can turn by hand if necessary...1RPM is an approximate speed slow enough to keep the graining in a straight line radiating out from the center ie. sunray/sunburst...apparently there is a difference between those two graining effects. 

Just to clarify !....there are two rotations taking place...the ratchet wheel and the device forming the graining effect.

The ratchet wheel's rotation must remain constant to maintain even graining across it. 

Bit more clarification as to whats going on....including my shitty evening

[mbwatch]

47 minutes ago, Neverenoughwatches said:

Just to clarify !....there are two rotations taking place...the ratchet wheel and the device forming the graining effect.

Ahhhh okay thanks for that. I knew snailing required two rotations, but was thinking that sunburst was done with a rotating part and radially moving, but not rotating abrasive.  This method could produce nothing but circular graining, though when that is fine enough it does have a similar effect on reflecting light.

My next challenge is getting the internet to agree on which finish type is "sunburst" and which type is "sunray". I think what I want for my ratchet wheel is "sunray" and my sketchy attempt produced something a little like sunburst (as found on dials).

Here, it sounds like they're spinning a brass brush that rotates across the full diameter of a stationary dial for the conventional sunburst dial (though they call it sunray) - so both rotations in the brushing tool, part stays fixed. https://www.timeandwatches.com/p/dial-making-at-glashutte-original.html

2 hours ago, Neverenoughwatches said:

I'm not quite sure on the process you used MB

I spend enough time here now I can scale back the anonymity, and I have observed that real names are used pretty frequently. My name is Michael.

[RichardHarris123]

Hello Micheal, bet you can't guess my name. Hehe. 

 

[Neverenoughwatches]

9 minutes ago, mbwatch said:

Ahhhh okay thanks for that. I knew snailing required two rotations, but was thinking that sunburst was done with a rotating part and radially moving, but not rotating abrasive.  This method could produce nothing but circular graining, though when that is fine enough it does have a similar effect on reflecting light.

My next challenge is getting the internet to agree on which finish type is "sunburst" and which type is "sunray". I think what I want for my ratchet wheel is "sunray" and my sketchy attempt produced something a little like sunburst (as found on dials).

Here, it sounds like they're spinning a brass brush that rotates across the full diameter of a stationary dial for the conventional sunburst dial (though they call it sunray) - so both rotations in the brushing tool, part stays fixed. https://www.timeandwatches.com/p/dial-making-at-glashutte-original.html

I spend enough time here now I can scale back the anonymity, and I have observed that real names are used pretty frequently. My name is Michael.

I'm still unsure as to which term is which, the best I could find was that sunburst relates to dials and sunray is an engraving technique used on steel wheels Anyways nice to meet you Michael ,  tbh I much prefer using our real names or a form off, some I use first Initials after I discover their name in case they prefer to remain anonymous.  Over time here many of us become what i would consider friends, colleagues in clockwork collaborations . I think I can put quite a few of us in that category. Which is nice to have that an extended framework of neutral friends.

Rich.

7 hours ago, mbwatch said:

and yes you guys all got me lathe shopping now)

It was just a matter of time Michael before you gave in

 

43 minutes ago, RichardHarris123 said:

Hello Micheal, bet you can't guess my name. Hehe. 

 

Harry ?

[JohnR725]

first link has terminology and hinting at how it's done. The second two links is a book you might find it interesting.

then if you look at YouTube there are lots of videos on finishing. for instance in this video ad about exactly 1 minute and 10 seconds it looks like a wheel.

2 hours ago, mbwatch said:

but was thinking that sunburst was done with a rotating part and radially moving, but not rotating abrasive.

actually the kind a wheel you're talking about here. Often times for wheel type refinishing you'll find that in books on watchmakers lathe as I'm sure I've seen it before in a book somewhere in the universe just can't quite remember which one. But in a case in the video look at the interesting patterns are doing on that wheel?

 

https://monochrome-watches.com/a-technical-perspective-all-you-want-to-know-about-finishing-in-haute-horlogerie/

https://watchprint.com/en/technical-insights/360-high-end-horological-finishing-and-decoration.html

https://www.booksimonin.ch/en/5640-horological-finishing-and-decoration,-hi.php