Laser Rust Cleaning Machine 1

[DGGT6]

thread380-462561
Hello,
This is my first post here and I hope I am in the right place.
I saw a previous thread about a laser rust cleaner and hoped someone here has had some experience with them.
I have just spent my kids inheritance and bought a 50W Fibre Laser from China and I am having mixed success with it.
It is great for light surface rust but doesn't seem to want to touch deeper pitted rust.
Hopefully I have uploaded a before and after photo as well as a video. The video shows the laser working really well.

I look forward to any discussion.
Many thanks,
Doug

 

[MacGyverS2000]

Fiber-based cleaning systems you see video of hand-held wands being used to "scrape" away rust are many 100's of Watts... your 50W isn't going to do more than what you've seen.

Dan - Owner

http://www.Hi-TecDesigns.com

 

[DGGT6]

Hello Dan,
Thanks for your reply.
From what I can ascertain from many of the laser suppliers, the more watts predominately only give you a faster pace of cleaning. This video shows that basically the 1000w is just faster (as well as "soft" and "rough" cleaning).

https://youtu.be/M5Zpz1g3iCY

The beam power specs for a 50W laser source is 1 Joule which is the same as a 100W source.
Here are the before and after photos I meant to upload.

The left over black marks/pitting are my concern. Is it rust the laser needs a different setting for (more/less kHz) or is the laser beam affecting/changing the pitted rust???????

Many thanks,
Cheers,
Doug

 

[MacGyverS2000]

Total energy (Joule) isn't the entire picture... you also have to consider the duration and/or peak energy of that transfer. I could stand behind a parked car pushing with my hand all day and it won't move... but if I can store that energy up and provide it in a single one-second burst, that car will end up across the parking lot. Also, don't assume that because you don't see shiny metal what you're looking at is rust... contaminants come in all shapes/sizes (i.e., chemical formulations).

Dan - Owner

http://www.Hi-TecDesigns.com

 

[IRstuff]

Or, you could wind up with a big dent in hood ;-)

The reason this works at all is that the rust absorbs the laser wavelength and energy. If it's not going away, it could be either that it's not red rust, but some other iron oxide, or it's just no longer shiny because of the surface specularity was damaged by the rust.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[DGGT6]

Thanks Guys.
Yes I had wondered if the remaining areas were red or other (black?) rust.
It is hard to photograph (and see visually) but I seem to notice that after cleaning a black area with a wire brush on a bench grinder, all/most the metal "appears" to be shiny and clean but after passing the laser over the area, the black spots seem to reappear which makes me wonder if the laser is "cooking" something in the bottom of the pitting?????

I have also used a scribe to scrape some of the black marks and the resultant dust is brown, not black.

These black marks are eaten away by the Evaporust Rust product so can I assume that the black is rust and not a contaminant?

I was reading that there is a difference between surface rust and "pitted rust". I thought "pitted" only meant it was found in pits below the surface, but is it an actual different chemical formula meaning the the laser does not ablate it?

Cheers,
Doug

 

[IRstuff]

What makes the difference between iron and steel is the carbon content. It's possible your laser is still heating up the surface enough to bring the carbon onto the surface. You may have insufficient power to convert the carbon to CO or CO2

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[DGGT6]

Ah, interesting thought!

 

[MacGyverS2000]

You're annealing the surface...

Dan - Owner

http://www.Hi-TecDesigns.com

 

[DGGT6]

Hmmm, so less heat maybe???
Will give it a whirl.
Many thanks,
Cheers,
Doug