Mirror finish for mild steel...?

[The Z'eer]

Though in comparison to how it looked before...



...it's a noticeable improvement.

 

[The Z'eer]

As said, every scratch you put in has the be taken out.

What's not been pointed out - you don't actually remove the scratch, you remove all the metal around it...

After getting rid of everything around the corrosion caused pitting, then working down the scratches, think about how much of the original metal thickness is left - I've seen stuff polished paper thin, like thinner than a coke can...

Point taken, thankfully the metal didn't become wafer thin through the abrasion/polishing process.

 

[hotrodder]

I'm using a 240 volt De Walt drill for the polishing process, could you comment if this is suitable for this application?

As you've shown it can the job done but it's not the most suitable... drills aren't designed to be used like that and as result it often kills the bearings in them if you make a habit of it. Most are usually lacking in torque and/or rpm too, with the right kit polishing to any given standard is a chunk faster. A lot of people convert bench grinders but be aware that cheapnese examples (whether bench grinders or buffing machines) don't have enough torque and often slow or stall if you sneeze near them. You need to be able to apply enough pressure to generate heat (and get the polishing soaps working) without the machine bogging down
There's usually several old UK made Wolf bench grinders on the bay that are in different league to cheapnese tat and with a bit of patience can be a chunk cheaper too. On paper they're nothing special but have more grunt than their data plate suggests. More money but for polishing stuff that's too big/heavy to hold there's also usually some hand held versions too, basically they're straight/die grinders on steroids

The price of chrome plating isn't cheap, and with this piece I won't be going down that route. Thanks for the info though

Chrome only really got mentioned as an example of mirror polishing steel, while the chrome (and underlying nickel and copper) obviously provides protection and a brighter finish as was said the steel part needs polishing to a high standard first or the chrome will just highlight every single flaw

 

[langy]

I think you would understand the process a lot better if you read a polishing article I did a few years ago, it's on here somewhere and will explain a lot for you, try a search and it should pop up

 

[henry Kadzielski]

Good afternoon The Zeer.
As has been stated before, and please note the machine you use has to have to speed and torque to be able to turn the mop with out stalling. This generates the heat to melt the 'soap' which contains the abrasive to polish your material. The more pressure you can put onto your job the faster the polishing process will be. Also polishing perpendicular to your last scratches is the fastest way to remove them
The finer the scratches are the faster the polishing will be. You probably will still need to change you soap from a coarse cut to a finer for final high polish. One very important thing to note, which I feel that no one has mentioned is the mess. The larger the job you come out looking like a black and white minstral. You have sh$t in you ears, nose, hair, down the back of your shirt and any where else you can think off. This is not a glamorous task

 

[500e]

Good gloves as well things get hot if you have enough torque

 

[The Z'eer]

As you've shown it can the job done but it's not the most suitable... drills aren't designed to be used like that and as result it often kills the bearings in them if you make a habit of it. Most are usually lacking in torque and/or rpm too, with the right kit polishing to any given standard is a chunk faster. A lot of people convert bench grinders but be aware that cheapnese examples (whether bench grinders or buffing machines) don't have enough torque and often slow or stall if you sneeze near them. You need to be able to apply enough pressure to generate heat (and get the polishing soaps working) without the machine bogging down
There's usually several old UK made Wolf bench grinders on the bay that are in different league to cheapnese tat and with a bit of patience can be a chunk cheaper too. On paper they're nothing special but have more grunt than their data plate suggests. More money but for polishing stuff that's too big/heavy to hold there's also usually some hand held versions too, basically they're straight/die grinders on steroids


Chrome only really got mentioned as an example of mirror polishing steel, while the chrome (and underlying nickel and copper) obviously provides protection and a brighter finish as was said the steel part needs polishing to a high standard first or the chrome will just highlight every single flaw

The drill hasn't stalled, and heat is generated when polishing. However I did have my doubts about such a tool for this application and as you've confirmed a drill isn't really a suitable one.

I'm keen to continue, and hopefully to perfect the job. Do you have a suggestion of a decent quality hand held tool which is suitable for the job?

 

[hotrodder]

The only handheld thing i'm aware of are the old Wolf straight grinders i mentioned. Google will get you some pics, there's usually a few listings on the bay and iirc somewhere on the forum Langy has posted pics of his (or something like it) in use. A search of the forum using terms like 'menzerna' will probably get the most useful stuff on polishing as that name usually comes up when talking soaps/compounds

Not much use for the type of mops you've bought but there are several types of finishing/graining/polishing abrasives designed for angle grinders but you need an example with adjustable speed or a lower rpm grinder as regular grinders will just muller the abrasives/polishing flap wheels. I've no idea if cheapnese adjustable speed angle grinders take much abuse at lower speeds... as with variable speed drills usually slowing them down kills most of the torque and overheats the motor more quickly

Pretty much any powertool will generate some heat in the part being polished. With the proper kit we're talking uncomfortably/scalding hot hence gloves being mentioned. Whenever i've used cheapnese bench grinders/polishers or mains drills they've struggled to generate enough heat to work properly or at least quickly/efficiently. At the end of the day results are mostly down to the person with the tools making the difference between boredom/frustration/calling it good enough/giving up and being able to polish something, clean up, have something to eat and spend the evening down the pub. One exception to that is the first time you use a 'real' bench grinder/pedestal buffer (or get complacent) and it rips whatever you're polishing out of your hands when you catch an edge etc, throws it across the room and bounces it off of several walls and the floor making a right mess in the process. Obviously this only happens when the part is nearly finished

 

[henry Kadzielski]

Good morning The Z'eer.
Here is a pic of my toys.
The top one is from Pferd and is specifically made for polishing, is variable speed lighter and used primarily with soaps for cut and polish.
The orange one is Fien and is basically a straight grinder and not variable speed. I use it for bigger roughing jobs as it is much heavier and got much more grunt. The only problem is that you cannot hang onto to if for long. The other use is on sisal mops 'the cream floppy ones' to polish off the residue from the polishing process ' the compound'.
Neither of these a cheap items, then there is the consumables and accessories, the list goes on

 

[langy]

As the others have said drills are not up to the job I'm afraid, the bearings are not set up for side loads that are incurred when polishing, I use the same tool as Henry for handwork but it's a beast to hold onto for any length of time.
I use a 4hp 3 phase proper polisher and you just can't beat it to be honest, it has enough torque to throw a 16 stone man into the wall if you get snagged in it so it's quite dangerous !!! It picked my mate up easily and broke his arm when he got snagged and it bashed him into the wall, I told him not to use it !!!

Polishing is a skill and you really need to read up about the ways of doing it, only then will you become good at it

 

[langy]

I found my old article posted in this thread which may help you http://www.mig-welding.co.uk/forum/...rom-steel-before-polishing.63947/#post-818536

 

[The Z'eer]

I think you would understand the process a lot better if you read a polishing article I did a few years ago, it's on here somewhere and will explain a lot for you, try a search and it should pop up

I did read the article, and a good one it is too. A question about the diameter of polishing wheels: would I be right in saying the larger the wheel, the greater the power is required to drive it effectively?

 

[The Z'eer]

I found my old article posted in this thread which may help you http://www.mig-welding.co.uk/forum/...rom-steel-before-polishing.63947/#post-818536

Thanks was reading that the other day.

 

[Chris Stevens]

The finish you have managed with a drill is pretty good, but the pipe would look poor if you were wanting to nickel of chrome plate. There is a world of difference between DIY polishing and polishing with a pro 3 phase spindle, and when I was struggling using a 240v bench grinder, found simply not enough power to use higher abrasive compounds such as Abracut.

For smaller parts at least I found using a kit from Moleroda to fit on an angle grinder, was far more effective than the bench grinder route. But this would probably not be ideal for rusty pitted ferrous parts. In the case of your exhaust, have you spoken with the electoplater you intend to use? Many wont touch things like used exhausts!

Would guess though if you wanted to persevere with DIY polishing your ferrous parts prior to plating, you should get pretty good results. Only problem here though is that it would probably take 2 hours to get anywhere near to what pro polisher could do in 20 minutes, so home polishing might not be cost effective?

 

[langy]

I did read the article, and a good one it is too. A question about the diameter of polishing wheels: would I be right in saying the larger the wheel, the greater the power is required to drive it effectively?

Yes you dont want to be using the 12" mops on the small machines as they will stall

 

[hareng]

Confirm a pedestal polisher some call a lathe are a world of difference to any higher hp bench grinder mod.
Where the pedestal scores can use course abrasives like 60 grit, sparks will fly with no effort just hang on. Only need to go down the grades to desired finish.
Hate polishing the last 17 years I do everything to get out of it. The Viceroy 10" pedestal been outside last 6 years with 3hp motor wired in reverse, just hang on eliminates the job grabbing and bouncing off 4 walls.

Bench grinders modded ok for short bursts on small parts with small 3-5" thin wheels. Will have to continuously touch job back off let grinder pick up speed, takes an eternity even with a 3/4hp. Have a 1/4hp Wolf that generates more torque than most 1/2hp cheapies.

 

[The Z'eer]

View attachment 92385 Good morning The Z'eer.
Here is a pic of my toys.
The top one is from Pferd and is specifically made for polishing, is variable speed lighter and used primarily with soaps for cut and polish.
The orange one is Fien and is basically a straight grinder and not variable speed. I use it for bigger roughing jobs as it is much heavier and got much more grunt. The only problem is that you cannot hang onto to if for long. The other use is on sisal mops 'the cream floppy ones' to polish off the residue from the polishing process ' the compound'.
Neither of these a cheap items, then there is the consumables and accessories, the list goes on

Nice tools quality and durability is certain. I had a look at the prices for such items, and they're not cheap although necessary for the purpose intended.

 

[The Z'eer]

The finish you have managed with a drill is pretty good, but the pipe would look poor if you were wanting to nickel of chrome plate. There is a world of difference between DIY polishing and polishing with a pro 3 phase spindle, and when I was struggling using a 240v bench grinder, found simply not enough power to use higher abrasive compounds such as Abracut.

For smaller parts at least I found using a kit from Moleroda to fit on an angle grinder, was far more effective than the bench grinder route. But this would probably not be ideal for rusty pitted ferrous parts. In the case of your exhaust, have you spoken with the electoplater you intend to use? Many wont touch things like used exhausts!

Would guess though if you wanted to persevere with DIY polishing your ferrous parts prior to plating, you should get pretty good results. Only problem here though is that it would probably take 2 hours to get anywhere near to what pro polisher could do in 20 minutes, so home polishing might not be cost effective?

Thanks It wasn't too bad considering the type of drill used. Sadly the 3 phase bench grinder isn't possible, so I've gotta make the best with tools available. Nickel and chrome plating isn't on the agenda, it's a mild steel exhaust with an intention on my part to remove corrosion and cheer the part up a little. The pitted corroded areas aren't repairable, it simply was an experiment and I fancied learning a new skill.