Putting a random swirl finish on aluminum

Learn and share abrasive & texturing finishing techniques, experiences, and product knowledge here.
Post Reply
motoguy
4 Star Elite Contributing Member
4 Star Elite Contributing Member
Posts: 1184
Joined: Tue Aug 25, 2015 12:05 pm
Location: Central MO, USA

Putting a random swirl finish on aluminum

Post by motoguy »

I have a roughly 4' x 4' aluminum (1/4") ranch sign I'm finishing up for a customer. The customer really like the swirl pattern she has seen in some of my wall hangings (120 grit flap wheel on mild steel, under Steel F/X patina and clear). This aluminum panel will be bare, just swirled and clear coated.

I'm curious how to get a good "swirl" pattern on this. I tried the 120 grit flap disc on a piece of scrap, and it just looks awful. Dull, flat, looks more like scratches than a swirl finish. Actually looks WORSE than the original finish, IMO. Do I need to use something like a scotchbrite pad to get the effect I want? Something like this, on a grinder backer plate?

http://www.lehighvalleyabrasives.com/co ... 02-scd4-vf

Or a "conditioning flap wheel": http://www.lehighvalleyabrasives.com/no ... -fd45nw-vf

I'm new to aluminum finish work, so I'm not sure of the best way to go. The clear coat should add some shine, but I'd like to know the best prep option for the metal.
Last edited by motoguy on Mon Feb 20, 2017 3:12 pm, edited 1 time in total.
Bulltear 6x12 w/ Proton Z axis & watertable
CommandCNC/Linux w/ Ohmic & HyT options
Hypertherm Powermax 85 w/ machine torch
Solidworks, Coreldraw X7, Inkscape, Sheetcam
User avatar
acourtjester
6 Star Elite Contributing Member
6 Star Elite Contributing Member
Posts: 7754
Joined: Sat Jun 02, 2012 6:04 pm
Location: Pensacola, Fla

Re: Putting an swirl finish on aluminum

Post by acourtjester »

Not sure if this will help but the process for what is called "engine tune finish" uses a compound and a leather pad. Aluminum is to soft for a flat wheel
DIY 4X4 Plasma/Router Table
Hypertherm PM65 Machine Torch
Drag Knife and Scribe
Miller Mig welder
13" metal lathe
Small Mill
Everlast PowerTig 255 EXT
motoguy
4 Star Elite Contributing Member
4 Star Elite Contributing Member
Posts: 1184
Joined: Tue Aug 25, 2015 12:05 pm
Location: Central MO, USA

Re: Putting an swirl finish on aluminum

Post by motoguy »

Thanks. I'm not really looking for an engine turned circular pattern finish, as much as a random "swirl pattern". She really liked the pattern under my patina'd monograms, so that is what I'm trying to duplicate. Similar to this swirl pattern on this piece:
IMG_2775_1487605810275.jpg
imagejpeg_1_1487605810778.jpg
Or like the pattern under this ribbon image I found:

Image

You currently do not have access to download this file.
To gain download access for DXF, SVG & other files Click Here

Bulltear 6x12 w/ Proton Z axis & watertable
CommandCNC/Linux w/ Ohmic & HyT options
Hypertherm Powermax 85 w/ machine torch
Solidworks, Coreldraw X7, Inkscape, Sheetcam
User avatar
acourtjester
6 Star Elite Contributing Member
6 Star Elite Contributing Member
Posts: 7754
Joined: Sat Jun 02, 2012 6:04 pm
Location: Pensacola, Fla

Re: Putting a random swirl finish on aluminum

Post by acourtjester »

yes that is quite a different swirl pattern from engine turned, almost looks like a fish scale pattern in some places. But more like a random swirl, no pattern, good luck on that one.
DIY 4X4 Plasma/Router Table
Hypertherm PM65 Machine Torch
Drag Knife and Scribe
Miller Mig welder
13" metal lathe
Small Mill
Everlast PowerTig 255 EXT
Largemouthlou
4 Star Member
4 Star Member
Posts: 1402
Joined: Mon Aug 30, 2010 5:56 am
Location: Palm Bch Gardens Fl
Contact:

Re: Putting a random swirl finish on aluminum

Post by Largemouthlou »

Try an 80 grit flap disk..
1250 hypertherm
4 X 8 Precision Plasma
CandCnC electronics
motoguy
4 Star Elite Contributing Member
4 Star Elite Contributing Member
Posts: 1184
Joined: Tue Aug 25, 2015 12:05 pm
Location: Central MO, USA

Re: Putting a random swirl finish on aluminum

Post by motoguy »

Largemouthlou wrote:Try an 80 grit flap disk..
I tried a 120, and IMO it looks horrible.
Bulltear 6x12 w/ Proton Z axis & watertable
CommandCNC/Linux w/ Ohmic & HyT options
Hypertherm Powermax 85 w/ machine torch
Solidworks, Coreldraw X7, Inkscape, Sheetcam
Largemouthlou
4 Star Member
4 Star Member
Posts: 1402
Joined: Mon Aug 30, 2010 5:56 am
Location: Palm Bch Gardens Fl
Contact:

Re: Putting a random swirl finish on aluminum

Post by Largemouthlou »

Sending you a message
1250 hypertherm
4 X 8 Precision Plasma
CandCnC electronics
sphurley
3 Star Elite Contributing Member
3 Star Elite Contributing Member
Posts: 445
Joined: Sat Jul 04, 2015 10:43 pm

Re: Putting a random swirl finish on aluminum

Post by sphurley »

Scotch pad discs is what I use.
https://www.mcmaster.com/#sanding-discs/=16ginfb
Steve
Platform CNC Plasma table
CandCNC Ethercut IV DTHC
Hypertherm 85/CPC/RS485
Miller 350P
Miller Dynasty 280DX
chevybythesea
2.5 Star Elite Contributing Member
2.5 Star Elite Contributing Member
Posts: 133
Joined: Tue Dec 08, 2015 1:06 am
Location: St. George, Utah

Re: Putting a random swirl finish on aluminum

Post by chevybythesea »

+1 on the flap disc with scotch pad. I use the "medium" grit, shown here: http://www.cgwcamel.com/catalogue/product/3558

I know it says it is for stainless, but works great for aluminum. Also has a "very fine" grit, closer to about 320 grit nominal.
5x10 ArcLight Dynamics Plasma table
http://www.thesteelyardinc.net
kkroger
2.5 Star Member
2.5 Star Member
Posts: 229
Joined: Sat Apr 26, 2014 7:56 pm

Re: Putting a random swirl finish on aluminum

Post by kkroger »

We do it with a 36 Grit Disk on a 4.5" Grinder....
Post Reply

Return to “Abrasive & Texturing”