What is ball burnishing?

[Ian_H]

Hi all, new here, been lurking while and going to dip my toes into retrobikes next year I think!

I'm looking for a bit of info on ball burnishing - I presume its some kind of media blasted finish applied to bare metal to acheive the desired look, but can it be done to a painted frame? I mean, strip the paint first and then get the 'ball burnished' or polished look? I presume its for aluminium only, oherwise steel would just corrode? What stops the aluminium from oxidising?

And, if you can take a frame, strip the paint and burnish it, is there anywhere UK based that does it?

SO many questions for a new guy I know! Thanks in advance for any info.

Ian.

 

[Logic.Al]

I think it was the frame was rolled in ball bearings to polish it.

 

[feetabix]

Welcome to rb Ian......it's a process of polishing and I think hardening a surface effectively using small balls, sandblasting but not using sand......any surface vulnerable to corrosion would then need preventative measures in a normal way.....I've never had it done but it appears to be used to buff up metallic surfaces where a shine is required rather than prep for paint or powder coating.......plenty of folk with more experience in it than I wil be along soon no doubt!......

 

[JeRkY]

http://en.wikipedia.org/wiki/Burnishing_(metal)

That is fairly comprehensive.

Nothing to do with sand blasting.

 

[MADJEZ]

Ball-burnishing... I thought it was where you landed after a jump and your testicles were
stamped between saddle & thigh causing that sick to the stomach feeling....

....I'll get my coat.

 

[sylus]

I'm glad someone asked this as I thought it was something to do with back crack and sack

 

[Ian_H]

Thanks for the replies, especially the Wiki (its a pottery link BTW, but you can follow it to the metal page!) Totally diffrent to media blasting as you say.

So, can it be done after a paint strip? Or you can you just strip the paint from an ally frame and polish it up, or is the surface too 'rough' for that?

And Madjez - I think you're thinking of Ball-Busting!

 

[cm_ls1]

I have a gt that's waiting to get built , which is half polished/painted.

But after reading this thread it could be ball burnished ?

 

[MADJEZ]

I have a gt that's waiting to get built , which is half polished/painted.

But after reading this thread it could be ball burnished ?

From decals that looks more modern. I'd say that's brushed from the pick.
Ball-burnished is shiny polished or a dull oxidised look.

 

[integerspin]

I would have thought the tube was ball burnished?
I mean the tube was burnished prior to making the frame.
Ball burnishing is probably pushing a hard ball into the surface and deforming the surface, so I would guess the tube is spun in a machine with fixed, opposing, balls that are pressed in to the surface. OK that may be way off, but look in a roller burnished tube[hydraulic ram tube] and you can imagine how it might be done.
The blasting with steel balls is shot blasting/shot peening and is a matt finish.