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Johnson T.





Joined: 12 Aug 2012

Posts: 29

PostPosted: Mon 01 Oct, 2012 2:38 am    Post subject: How to polish mild steel and seal it?         Reply with quote

Now before anybody tells me, yes, I have used the search function. Am I the only one who finds it completely useless? WTF?!

When you buy helmets they will ALWAYS be covered in scratches for no reason. One person even scratched an arrow into my helmet to tell his friend how to put the brass on the right way. OH GOD WHY???

Sandpaper is a useless object. One you make scratches in it with 600 grit sandpaper or lower, you CANNOT fix it. I do not use sandpaper anymore because even spending four hours carefully polishing it with 10 grades of sandpaper can't fix the damage the first piece.

1. How do I buff scratches out of a helmet?

Now onto protecting. I don't use any kind of oil anymore because it gets covered in atmospheric dust and garbage and soil which makes the helmet rust faster. It's too hard to keep helmets oiled and even harder to handle them.

I use Ren Wax because it dries hard and supposedly is all you need to protect helmets.

2. How often do I need to polish my helmet with Ren Wax and how do I clean the helmet after use without removing the wax? Exactly how do I know when I need to Ren Wax it again?

Often my helmets COME as black spotted or pitted. Or I even cause it myself with finger spots. It doesn't look like rust, it just goes black in places and polishing it only improves it slightly.

3. What are these black spots, are they rust? If so, how do I remove them? Is it safe to put Ren Wax over rusted surfaces or will it spread underneath from sealing oxygen inside the surface coat?

I hear WD40 and Brasso are evil and Rust Remover is bad too because it destroys the surface of your helmet. I use a polishing compound called Autosol but if you don't get it all off it makes it green.

I don't use turpentine or methylated spirits to clean my helm because it leaves oily residue.

4. How do you completely remove all oil, dirt and polish from a helmet?

OH THANK YOU! Cool
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Thomas R.




Location: Germany
Joined: 10 May 2010
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Reading list: 17 books

Posts: 395

PostPosted: Mon 01 Oct, 2012 6:23 am    Post subject:         Reply with quote

For propper polishing you will need at least three polishing discs and the right polish for each one. You start with a sisal disc, then linen, and cotton in the end with very fine polish (it is normally the red one). Change direction of polishing with each disc by 90 degrees.

Regards,
Thomas

http://maerenundlobebaeren.tumblr.com/
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Johnson T.





Joined: 12 Aug 2012

Posts: 29

PostPosted: Mon 01 Oct, 2012 6:39 am    Post subject:         Reply with quote

Thank you Thomas. I'm not using a machine I gave the wrong idea when I said buff. I'm polishing by hand.
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Michael Pikula
Industry Professional



Location: Madison, WI
Joined: 07 Jun 2008

Posts: 411

PostPosted: Mon 01 Oct, 2012 8:32 am    Post subject: Re: How to polish mild steel and seal it?         Reply with quote

Johnson T. wrote:
Sandpaper is a useless object.


?????????????? I have no clue how you can say that sandpaper is a useless object. There are many different grits, types of abrasives, types of adhesives, types of backing, and blocks, all of which make a HUGE difference in the performance of the product. I use sandpaper to finish hardened steel on swords, and trust me, it works.

If you have scratches, buffing isn't going to get scratches out. Buffing is a surface treatment, and at best, if they are very shallow, you might be able to make them not as noticeable, but when they catch direct light they will show. A satin finish will be better at blending them away. If you receive a product from any craftsman and it has scratches that you are not happy with you should get in touch with the maker and resolve the situation. If someone
Quote:
scratched an arrow into my helmet to tell his friend how to put the brass on the right way
and this is visible from the outside, there is no excuse for this kind of unprofessional craftsmanship.

Just like everything in this world, you get what you pay for, and you get out what you put in. Your post indicates that you are not satisfied with the product, and I suggest you address this concern with the person you did business with. There is no reason to accept sub par work, for any reason.

By the way, I have used the search function many times and it has never failed to supply the information that I have sought. Happy
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Joel Minturn





Joined: 10 Dec 2007

Posts: 232

PostPosted: Mon 01 Oct, 2012 8:52 am    Post subject:         Reply with quote

I have shined my mild steel knee and elbow cops to a shine by hand and might have few things to add.

1. you mention 600 grit sandpaper is the starting grit or the ending grit or just a don't go below? I would start with 800 grit and go to 2000 grit sandpaper. It helps to use the wet/dry stuff and have a bucket of water to clean off the sandpaper with.
2. Once you finish with the 2000 grit paper then switch to the polishing compound and work your way through the various grades of that. (course, medium, fine) likely only course will make a difference.

you may be able to buff slight scratched out of a helmet but if they have any depth its going to be sandpaper first then buffing.

and yeah there is no way to get around this taking time and "elbow grease"

As for Ren Wax, heard good things about it, seems to work well. I have used car wax to keep my stuff shiney and that works well. I would redo the wax after any decent use of the helmet or if it was going to be put away for a while. As for cleaning it with out hurting the wax? hmm a bit of warm water and little soap might do the the trick. I would use gun oil to clean it off but you mention later that You don't want things that leave an oily finish so thats out.

4. The best way to completely remove oil, Brake cleaner, Its a strong cleaner that leaves no residue as that would hurt braking, Think carb cleaner is similiar. Don't want nasty chemicals? then hot water and soap followed by wiping it off with alchol to remove any soap residue and remaining water.

Hope somethign in this long winded reply helps/
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JE Sarge
Industry Professional



PostPosted: Mon 01 Oct, 2012 9:10 am    Post subject:         Reply with quote

For scratches, tarnish, and rust - I always go with a black finish-stripping sponge, like you use on cars and furniture. It's very rough finished, probably around 100-120 grit or so. Then I go with 240 grit paper, I then go to a green Scotchbrite pad (400ish grit), then a grey Scotchbrite pad (600-800ish), then metal polish. I finish up with fine steel wool. This method has always worked for me for years, on both swords and armor.

To keep the rust/tarnish off, I use a silicone gun/reel cloth. Some people disagree with using these, but I have used them for years and years with no problems whatsoever, even when leaving things in storage untouched for over a year. If the silicone has an adverse effect on metal finishes, I've not seen evidence of it in over 20 years, on my firearms, swords, or armor items. It's simple and it works. Happy

J.E. Sarge
Crusader Monk Sword Scabbards and Customizations
www.crusadermonk.com

"But lack of documentation, especially for such early times, is not to be considered as evidence of non-existance." - Ewart Oakeshott
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Kai Lawson




Location: Madison, WI
Joined: 26 Aug 2010
Likes: 7 pages

Posts: 481

PostPosted: Mon 01 Oct, 2012 10:58 am    Post subject:         Reply with quote

I have a horribly noob-ish question about polishing rust off metal: I have heard (and I try not to spread this around, in case it is wrong) that using fine sand on flat metal surfaces will remove rust. However, won't this leave uneven scratches/trackways that can then act as further rust 'hotspots?' How would rust have been cleaned off of helmets and sword blades and spearheads (wider, more planar surfaces) post-battle or on campaign without incurring these pits or scratches?
"And they crossed swords."
--William Goldman, alias S. Morgenstern
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Tjarand Matre




Location: Nøtterøy, Norway
Joined: 19 Sep 2010

Posts: 158

PostPosted: Mon 01 Oct, 2012 11:56 am    Post subject:         Reply with quote

For my Via Armorari armour I use Meguiars automotive polish products. Works like a charm and also smells good.
The armour is hand filed and any rust and oxidation tends to run deep. The Meguiars product line really clean any blemishes up nicely. Just treat your armour like any aging car and it will shine like new. I have also used Autosol on deep rust on my swords. But I use a Dremel with a polishing disk to blast off the grime ...
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Bryce Felperin




Location: San Jose, CA
Joined: 16 Feb 2006

Posts: 552

PostPosted: Mon 01 Oct, 2012 2:55 pm    Post subject:         Reply with quote

Joel Minturn wrote:
I have shined my mild steel knee and elbow cops to a shine by hand and might have few things to add.

1. you mention 600 grit sandpaper is the starting grit or the ending grit or just a don't go below? I would start with 800 grit and go to 2000 grit sandpaper. It helps to use the wet/dry stuff and have a bucket of water to clean off the sandpaper with.
2. Once you finish with the 2000 grit paper then switch to the polishing compound and work your way through the various grades of that. (course, medium, fine) likely only course will make a difference.

you may be able to buff slight scratched out of a helmet but if they have any depth its going to be sandpaper first then buffing.

and yeah there is no way to get around this taking time and "elbow grease"

As for Ren Wax, heard good things about it, seems to work well. I have used car wax to keep my stuff shiney and that works well. I would redo the wax after any decent use of the helmet or if it was going to be put away for a while. As for cleaning it with out hurting the wax? hmm a bit of warm water and little soap might do the the trick. I would use gun oil to clean it off but you mention later that You don't want things that leave an oily finish so thats out.

4. The best way to completely remove oil, Brake cleaner, Its a strong cleaner that leaves no residue as that would hurt braking, Think carb cleaner is similiar. Don't want nasty chemicals? then hot water and soap followed by wiping it off with alchol to remove any soap residue and remaining water.

Hope somethign in this long winded reply helps/


Second on Ren Wax. It's cleaner than oil and lasts a long time if the item isn't used. Once it's used and scuffed up from use, then just reapply after polishing again.

One last word. Your kit needs to be maintained ALWAYS after use. Otherwise it just gets harder to maintain it if you don't care for it each time you use it.
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Peter Messent




Location: Texas
Joined: 03 Jan 2009

Posts: 226

PostPosted: Mon 01 Oct, 2012 5:50 pm    Post subject:         Reply with quote

Sandpaper is far from useless - IMO it's about the most useful tool I have. Definitely the most useful throwaway! Unfortunately as has already been mentioned, there is a LOT of variety in sandpaper and some sandpaper is complete garbage. Ideally, I only like to use quality wet-or-dry paper. High grits can be obtained from auto stores for car/motorcycle painting, but I have sometimes had to make do with bad paper - it's better than nothing, sometimes. The size of the scratches usually dictates the grit you have to start with but it's better to start too high than too low. If you start low you have to work up from that point, but you can always switch to a lower grit until you get the job done. If the paper isn't getting rid of the scratch, you may need a coarser paper.

The softer the material, the easier the job, and the faster your abrasive can clog up with crud - wet paper really helps, to serve as a lubricant and to prevent the paper clogging. It also gives a finer finish, as the small particles become suspended in the water and that slurry will do much of the cutting on its own. Same principle for using a quality waterstone for sharpening a knife.

Softer materials can also handle larger jumps in grit sizes - I'll sometimes go from 100-400-800 on copper, something that would not be quite as successful or expedient on hardened steel. Generally it's better to jump by no more than 200 up to 1000 - or less on the VERY rough grits (40-60 range).

Using sandpaper properly and with good result can be a difficult thing because it often looks worse before it looks better, and can be very time consuming and exceptionally fiddly to get into some gaps and corners. It does scratch the surface, if it didn't then it wouldn't be doing anything at all - it is, after all, abrading the metal down to the depth of the scratch.

I have no idea whether this interests you or not, but a softer finish than a high polish is much easier to maintain and shows scratches/dings/minor corrosion less readily. It does not have to be a brushed-type finish with lots of parallel scratches, it can also just be a uniform duller, cloudy finish. Steel wool can achieve this at times, though it largely depends on the medium in my experience.

The ren wax should be applied/buffed after handling and use, it's not ideal for a helmet that will be frequently handled or used IMO.

The black fingerprints are iron oxide, which is chemically similar to, but not, rust. Rust is the reddish-brown, often crusty and structurally weak, oxide of iron - I believe there are 16 oxides of iron, and I think only two are red-brown. Both red and black/grey iron oxides are used, historically and in modern times, to inhibit harmful corrosion. I have induced, then halted and sealed a red-orange surface rust on knives and axes to prevent damaging rust from forming. It is very common to use acids on knives to do the same thing, though generally causing a black-grey patina to form. That being said, I understand that a lot of people don't want these blemishes and polishing is generally enough to remove small fingerprints and the like. If not, a very high grit sandpaper followed by polishing should suffice.

I also like the silicon gun cloths as Sarge mentioned - they're good to steel in my experience and very easy to use.

A couple tips:
Backing sandpaper with good duct tape can really extend the life of the paper, particularly when used wet. It also helps it to tear in nice straight lines.

A bit of foam mouse mat glued to a wood block can make a great soft backing. Leather is also good for this. I also use the rough side of leather with polishing compound on it.

Hope that helps some,
Pete
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Johnson T.





Joined: 12 Aug 2012

Posts: 29

PostPosted: Tue 02 Oct, 2012 1:25 am    Post subject:         Reply with quote

Sandpaper just does not seem to help. Once you start using sandpaper, the scratches it causes are not repairable by going up another grade there.

If you start at 400 and go to 600 for example, the 600 won't polish back the scratches by the 400. I have found steel to be more vulnerable to scratches from sandpaper than chrome plated.

Next time I will use detergant and hot water maybe.

Peter are you saying that iron oxide on the metal is a GOOD thing because it protects it from even furthur oxidizing (as long as you cease the processes by waxing it) then?
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Daniel Wallace




Location: Pennsylvania USA
Joined: 07 Aug 2011

Posts: 580

PostPosted: Tue 02 Oct, 2012 9:43 am    Post subject:         Reply with quote

all of us do it yourselfers and the industry professionals use a verity of abrasives to get metal back to a polished state. your other option that i do not recommend is to used an acid to clean the steel. hydro chloric and sulfuric acids are used in the steel industry to give their polishes, but that still chewing away at the surface of steel and is very dangerous to attempt yourself. not to mention to get uniform.

my step by step guide for polish - and i use a little 3 in one oil instead of water while i'm sanding to help keep the newly exposed steel form oxidation.

start with 320 grit paper
slightly change sanding direction and move to 400
again slightly change sanding direction and move to move to 600
next move to buffing wheel with #5 buffing compound and clean with acetone or paint thinner
next move to a separate buffing wheel with # 6 compound and clean again

this will result in a mirror polish for steel, or if you want a satin finish you just stop at the desired grade of paper. but the finer the sanding, the better protection. this method will work for just about any softer metal you may be working with as well. if you have deep scratches that you see between sanding - you have to go back to your heaviest grade of paper and continue to sand out the scratchs until its level with the surrounding area. this can be a pain with deep scratchs you may get them to a point where you just have to live with it but in my experience working a while with the 320 will save you time in the end for your final polish.

protective oxidation is trick to pull off but possible. we all use different types of protections as well, i have used a variety wax actually can trap particles if you used correctly, silicon gun oil or lube is excellent. for a long term sealer - i've got a small side project that i'm going to attempt a clear powered coating. power coating from what a friend is telling me is as strong as steel, will not chip and will not scratch. i'll tell my results after i get a pice done.
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Michael Pikula
Industry Professional



Location: Madison, WI
Joined: 07 Jun 2008

Posts: 411

PostPosted: Tue 02 Oct, 2012 10:13 am    Post subject:         Reply with quote

Johnson T. wrote:

If you start at 400 and go to 600 for example, the 600 won't polish back the scratches by the 400.


This simply is not true. If you are seeing scratching when you switch grits, then you are either starting at a grit too fine for the scratches that are present, or you are switching to a finer grit too soon. Alternating the direction of your stroke with the sandpaper with reveal all the areas you missed. I know of craftsman who start 220 grit sandpaper and work their way up to 2000 grit. It works, this is a fact!

Using sandpaper works very well, but you have to use it properly, and you have to spend a lot of time and elbow grease. The finer grit sandpaper wears and load very quickly so you end up going through a good deal of it. An overwhelming amount of craftsman who hand finish their work use sandpaper. Saying that it doesn't work is spreading misinformation.
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Bryce Felperin




Location: San Jose, CA
Joined: 16 Feb 2006

Posts: 552

PostPosted: Tue 02 Oct, 2012 2:27 pm    Post subject:         Reply with quote

I use three methods to polish my swords, knives and such. I use sanding sponges instead of sandpaper, seems to work better for me and it is easier on my fifty year old hands.

First I use a 600-800 sanding sponge, which is easy to get from the painting isle at Home Depot or any other hardware store. I use this sponge to get out the rust only, and only use this till the rust is gone. For fingerprints, slight blemishes or discolorations I go to step two.

Next I use a 2400 grit sanding sponge I bought direct from the 3M website. It's buried in their website and not available in any hardware store I've seen, but I paid good money for a box of them and have only used half the box over the last five years. This sanding sponge WILL polish your surface very well. I use it with circular motions until all the blemishes, discoloration and general offending marks are gone. Then if I really want to get a serious mirror finish, I go to step 3.

Polishing paste can be gotten from any hardware store, or even supermarkets. It works easy with a dry clean cloth to polish out fingerprints or blemishes just like the 2400 grit sanding sponge, but it does a nice job also of polishing to a mirror finish any smooth enough metal with a simple circular motion after you applied it to the surface.

Generally, I find the 3M sand sponge does the job fine without me having to go to the paste, but in some cases I go to the paste if I want that blinding mirror finish on my surface. Make sure you use a clean cloth with the paste, and do it in an area where you can control the mess (not on your wife's expensive antique chair for example) since leaves black residue when you wipe it off the surface.

Also apply another clean cloth over the surface after you think you're finished, there may be a spot where the paste or dirty debris accumulates (like around the guard/blade boundary) that might need a wipe down.

Last I apply a coat of Renaissance Wax liberally over all surfaces with another clean cloth. This will allow you to keep it corrosion free almost indefinitely if not handled (like displaying it on your wall). However if you handle your weapon a lot, then I would suggest oil of some kind (like linseed oil) for that purpose. I usually just use the Ren Wax and re-clean after each use or the at the end of an event day. But I'm anal about that anyway. If you're doing an event and your weapon gets handled a lot over the weekend, then you probably don't want to keep a mirror finish anyway and should just sand the rust off and apply oil. A working tool needs different maintenance than a display one.

Regards,

Bryce
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Peter Messent




Location: Texas
Joined: 03 Jan 2009

Posts: 226

PostPosted: Tue 02 Oct, 2012 5:23 pm    Post subject:         Reply with quote

Johnson T. wrote:
Sandpaper just does not seem to help. Once you start using sandpaper, the scratches it causes are not repairable by going up another grade there.

If you start at 400 and go to 600 for example, the 600 won't polish back the scratches by the 400. I have found steel to be more vulnerable to scratches from sandpaper than chrome plated.

Next time I will use detergant and hot water maybe.

As mentioned by others, changing the direction of sanding is a great way to tell when you've removed the scratches from the previous grit. If you have any crosshatching, you need to continue until the scratches are all parallel, then switch direction again for the next grit. Do not use circular motions with abrasives this coarse.

Chrome is more abrasion-resistant than steel, so it does tend to scratch less - but if your sandpaper isn't scratching, it isn't doing anything at all. The scratches are necessary, as they are a sign of abrading away the blemished metal. The object is to make the scratches smaller and smaller until they are polished out, not to just erase them.

Johnson T. wrote:
Peter are you saying that iron oxide on the metal is a GOOD thing because it protects it from even furthur oxidizing (as long as you cease the processes by waxing it) then?

Whether or not it is a good thing is a very subjective question. I think that it's a good thing, I hate mirror polishes 90% of the time and like the character that a patina adds. Waxing is not necessary to stop the corrosion process. If you are rusting steel to protect it from corrosion, wax or oil (I dip a finger in linseed oil, rub it over the rust and then wipe dry) serves as a sealer because the rust itself will absorb moisture and it tends to be a fragile coating.

Before and after oiling:



If I use vinegar or some other acid to corrode metal, I halt the process by pouring baking soda over it to neutralize the acid and then wash it clean with water. Boiling water can be good, because it dries off the blade very quickly by evaporation and thorough drying is important. I don't apply any waxing/oiling to a gray or black patina unless it will be packaged up or put in a scabbard, etc. It's worth noting that the tannic acids in leathers can cause corrosion on steel, so straps on an armor harness may cause some blemishes.

Corrosion is the bane of anyone who wants their gear mirror polished. Corrosion appears VERY rapidly on a lot of simple steels. If you like a rustic look, though, maintenance is much easier and it will slow the development of damaging corrosion, in my experience. A lot of people simply speed the process up so that their polished steel doesn't look bad while it is transitioning from new to rustic "the natural way".

Hope this helps,
Pete
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Johnson T.





Joined: 12 Aug 2012

Posts: 29

PostPosted: Tue 02 Oct, 2012 11:39 pm    Post subject:         Reply with quote

Michael Pikula, what I meant was not scratches that already existed on the steel, I mean the scratches caused by the sandpaper.

In order to get the rust off steel you often need to use sandpaper tough enough that it scratches the steel in the process. So for example, 600 sandpaper scratches up your helmet while removing the rust, but 800 sandpaper doesn't remedy the scratches caused by the 600 paper.

Peter, if the sandpaper isn't scratching that doesn't necesarily mean it isn't working. It's true that if your sandpaper is damaging the surface of the steel it will get the rust off, but when it comes to sandpaper on chrome, I can polish chrome without scratching it up at all. Chrome seems to scratch less at lower grades of sandpaper than steel.

My problem is that when I'm polishing steel with sandpaper, either to get scratches out or to fix rust, it just makes it worse and even careful time consuming buffing with higher won't fix the initial damage.

Also Peter, would I be right in saying that having a very fine and controlled film of rust over the metal allow waxes and oils to penetrate better to prevent furthur permanent damage?

For example if you have a mirror finished thing, waxes and oils aren't going to soak into it very well because the microscopic planes of the steel are smooth and there's no gaps for the protective layers to adhere. They're basicly just sitting over the top rather than sinking in.
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Daniel Wallace




Location: Pennsylvania USA
Joined: 07 Aug 2011

Posts: 580

PostPosted: Wed 03 Oct, 2012 9:45 am    Post subject:         Reply with quote

Johnson T. wrote:


In order to get the rust off steel you often need to use sandpaper tough enough that it scratches the steel in the process. So for example, 600 sandpaper scratches up your helmet while removing the rust, but 800 sandpaper doesn't remedy the scratches caused by the 600 paper.



WTF?! i believe he already answered this for you. if the 800 is not removing the 'scratches' for you, you have to find a grit between 600 - 800. an automotive shop usually carries sanding paper at 100 grit levels. if your going to a home improvement store, your probably not going to find as many varieties becuase those stores are trending toward wood working. auto body repair shops will have a bigger selection of what your looking for in sanding papers. it's also good to make sure you have wet/dry sand paper. using a dry sand paper wet will make a mess.

i think you have a lot of information here to draw from. maybe find a piece of steel and try a few of them to find out what works best for you. its always better to test a method out before applying it to something you value, and if you have trouble anyone here can help you with the method you try.
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U. M. Tønner




Location: Denmark
Joined: 26 Apr 2008

Posts: 18

PostPosted: Wed 03 Oct, 2012 10:57 am    Post subject:         Reply with quote

I am truly sorry if I'm splitting hairs here, but ar you using actual sandpaper or are you using emery cloth?
I usually use emery cloth, grit 150 or so for rust removal, and if needed or I'm lasy i use 150 or 240 grit emery cloth fan grinders in ar hand held electrical drill. this gives af sort of satin finish which I find pleasing, and it's a good base for mirror polishing later.
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Joel Minturn





Joined: 10 Dec 2007

Posts: 232

PostPosted: Wed 03 Oct, 2012 5:39 pm    Post subject:         Reply with quote

Peter Messent wrote:

A couple tips:
Backing sandpaper with good duct tape can really extend the life of the paper, particularly when used wet. It also helps it to tear in nice straight lines.

A bit of foam mouse mat glued to a wood block can make a great soft backing. Leather is also good for this. I also use the rough side of leather with polishing compound on it.


I like the Duct Tape tip. Hadn't heard that before but it makes sense I'll have to start using it.

So while we are sharing tips. I that I had heard was to mark the piece being sanded with a permanent marker. Can be as simple as a line were the sanding is going to happen. Sand till the mark is gone then switch to a higher grit paper. That lets you know that you have done all that you can with that paper.
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Peter Messent




Location: Texas
Joined: 03 Jan 2009

Posts: 226

PostPosted: Thu 04 Oct, 2012 3:17 pm    Post subject:         Reply with quote

Johnson T. wrote:
Peter, if the sandpaper isn't scratching that doesn't necesarily mean it isn't working. It's true that if your sandpaper is damaging the surface of the steel it will get the rust off, but when it comes to sandpaper on chrome, I can polish chrome without scratching it up at all. Chrome seems to scratch less at lower grades of sandpaper than steel.

Well chrome is a very different animal to steel. For one thing, it doesn't rust. If chrome appears to be rusting, it's generally because the ferrous metal beneath the chrome plating is rusting and is showing through the chrome. Chrome is also generally more wear resistant than steel. Steel, unless very hard, WILL be scratched by sandpaper and that is most definitely a necessary evil when it comes to removing scratches and rust.

Johnson T. wrote:
My problem is that when I'm polishing steel with sandpaper, either to get scratches out or to fix rust, it just makes it worse and even careful time consuming buffing with higher won't fix the initial damage.

If 800 is not taking out the scratches from 600, you need to keep going with the 800, or switch to an interim between 600 and 800 as Daniel stated. If the sandpaper has taken a metallic sheen, it is clogged with metal and needs to be replaced - sanding wet helps prevent this from happening. If it's just not working any more, it's probably worn out. Wet sanding also helps to prolong the sharpness of the paper. If the 600 grit left scratches, then you know that the paper IS working (removing metal). You just need to work more with the higher grits. It's a process and requires elbow grease and patience. How large is the patch of metal you are referring to and how long did you take sanding it?

Johnson T. wrote:
Also Peter, would I be right in saying that having a very fine and controlled film of rust over the metal allow waxes and oils to penetrate better to prevent furthur permanent damage?

For example if you have a mirror finished thing, waxes and oils aren't going to soak into it very well because the microscopic planes of the steel are smooth and there's no gaps for the protective layers to adhere. They're basicly just sitting over the top rather than sinking in.


Indeed, that is the case. I can't comment a great deal on waxes, but that is certainly true for oils. I used linseed oil because it would cure and therefore offer better resiliency and wouldn't risk going rancid.
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