The Armour Archive

I'm getting some good work done on the pauldrons. The coarse grind is complete and I'm a few hours in on the next process. Pics tomorrow.

Mac

Mac wrote: The first grinding operation differs from all subsequent processes in an important way. It must remove the hammer marks and other small irregularities from the surface. It is a leveling process. This requires an unyielding presentation of the abrasive that will take off the high spots without flowing into the low spots. The first grinding operation defines the final form of the armor. All subsequent processes are just about removing scratches.

Mac

This is a very very important concept that even many fairly accomplished armours don't fully comprehend.

Tom B. wrote:

Mac wrote: The first grinding operation differs from all subsequent processes in an important way. It must remove the hammer marks and other small irregularities from the surface. It is a leveling process. This requires an unyielding presentation of the abrasive that will take off the high spots without flowing into the low spots. The first grinding operation defines the final form of the armor. All subsequent processes are just about removing scratches.

Mac

This is a very very important concept that even many fairly accomplished armours don't fully comprehend.

My statement above is a bit of an oversimplification, but the underlying concept is underappreciated.

I feel remiss about not posting more about finishing techniques, but at the same time I feel that my knowledge is so incomplete that I am loath to say anything that will turn out to be wrong.

In general we modern armorers are pretty tight lipped about our finishing processes: more so even than our metal forming processes or our beloved templates. I don't know how many of us are kept quiet by uncertainty, and how many by a desire for secrecy. Either way the silence is rooted in insecurity, and we all need to "grow a pair" and start discussing this subject.

Mac

Mac wrote: I feel remiss about not posting more about finishing techniques, but at the same time I feel that my knowledge is so incomplete that I am loath to say anything that will turn out to be wrong.

In general we modern armorers are pretty tight lipped about our finishing processes: more so even than our metal forming processes or our beloved templates. I don't know how many of us are kept quiet by uncertainty, and how many by a desire for secrecy. Either way the silence is rooted in insecurity, and we all need to "grow a pair" and start discussing this subject.

Mac

Mac, I've seen it posted somewhere before... "The craftsmen of old had their secrets, and those secrets died with them. We are not the better for that, and neither are they."

I believe it's far better to give all the information you have and let everyone else figure out the inconsistences and gaps through discussion and trial&error. Remember, as much as we are learning from you, this is a fourm and not a lecture. It's good to have that back and forth to benefit us all. Otherwise, we're all stumbling around like drunks in the dark.

I'm currently engaged in removing the marks from the coarse wheels. In general, the rule is "use the wheel with the largest radius that can be made to fit the work". By extension, one does best to start with the small wheels in the tight spots whenever possible and then go to larger ones for the "easy" areas. That's not what I'm doing here, and I will explain why in a bit.

I'm using 80gr PSA discs to remove the coarse marks and to try to remove any faceting as well.



In flutes, that means that only the very edge of the disc gets used. Consequently only the edge is consumed.



These discs end up in stacks on the bench, awaiting their next assignment.



I have a small fleet of backing pads of gradually diminishing size, and the discs will work their way through that fleet until they are too small for anything.



Doing that means having to trim the edges of the discs to fit the next size of pad. That happens with the "special" scissors. The only scissors in the shop that is ever used on abrasive paper is this one. Sandpaper ruins the edges of scissors very rapidly, and there is no sense using anything but the cheesiest sort of scissors. You can see for the shape of the edge that they have been reground more than once.



A few brisk and fiery passes across the coarse wheel of the bench grinder every few months keeps them in adequate shape to perform their self destructive task. It should be noted that time spent kludging up the edges on the sandpaper scissors is good practice for learning to sharpen up your good scissors.



So, the upshot of all that is that I am starting with the larger, rather than smaller discs because of the logistics of the thing. I need to wear out larger discs to make smaller discs. The effect on the final finish is minimal. Mostly it just means that I have to go back and touch up a bit more than if I were able to start with the small discs.

Wherever possible, I use the belt sander with a platen. This does a better job of removing the facets and makes for a much smoother shape than is possible with discs. On the main plates of the pauldrons, the only place where I can do that is the narrow area above the flutes. I'm using 180gr belts here, and I hope that the edges do not get me into too much trouble. As I mentioned a few days ago, these belts are really too stiff for this sort of work, and their edges tend to gouge. I'll probably end up coming back with the discs to fix the transitions into the flutes.



There are places, though, where a flat platen is difficult to use. I can sometimes use the very end of the platen to get into places that would be fouled otherwise.



The more I think about it, the more I think I need to make up a few "bellied" platens. Perhaps ones with radii like those big wheels that we see in images of armor polishers. I wonder if I have enough travel in the tension adjuster of my machine for that.....

Mac

Mac, it looks like the edge of the sandpaper is like 1/16" too big for the pad and folds over a bit. Is that intentional? And if so, does that help blend the bottoms and sides of the flutes? Or is it just a consequence of what's available and it ends up rutting and carving a bit more in places that you'd rather it not?

Also, my last post wasn't supposed to be too serious, just poking a bit of fun at the idea of you not sharing as much information as you could because you weren't sure 100% sure about it.

I had a near disaster this holiday when the cats spilled a pitcher of water intended to water the X-mas tree. The water leaked through the floor and rained on my workshop splashing a number of tools. Thankfully the rust came off with scotchbrite and I didn't need to kill the cats...

So I'm watching this thread and it got me thinking. All this work polishing and it could be months before the polishing is complete. The environment is not kind to steel, even in the dry of winter. What do you do AFTER polishing to preserve the finish until you do the final blackening or final hand-polish before delivery?

Thanks,
Sean

Hi Mac

You can get very nice grinding wheels made with rubberized abrasives (search Cratex Rubberized abrasive) which run at "normal" grinding speeds and don't gouge the living daylights out of your work - I sent the "nub" of one home with Jeff Wasson the last time we were together so I need to follow up and see if he found it a useful addition to his toolbox.
(Edit - get the "medium" or "coarse" wheels - the fine or XF wheels are a bazillion grit and will polish your work, but take forever to cut into it)

In general I use the abrasive backed discs *without* doing your coarse grind first, but I know that we have different techniques, specifically:

• I tend to start with lighter stock
• I (used to) work in stainless steel a lot
• I haven't done as much fluting as you have
• I spend a lot of time planishing, which cleans up a lot of what you take out with the grinder
• I don't make armour for money, so operational efficiency hasn't been a priority

With dense fluting it's a lot harder to planish out errors, so I can see that "pushing" one towards using abrasives (and requiring a non-flexible first pass to "dress" your surface)

I'll have to try your (and Wade's) methodology starting with thicker material and compare both time and final thickness / weights of pieces - part of why I have done it the "laborious" way is being insecure about my technique, but you are probably right that I am better off with more stuff in my scrap bucket and a wider appreciation of how techniques can (and can't) go together.

Scott Martin

Ckanite wrote:Mac, it looks like the edge of the sandpaper is like 1/16" too big for the pad and folds over a bit. Is that intentional? And if so, does that help blend the bottoms and sides of the flutes? Or is it just a consequence of what's available and it ends up rutting and carving a bit more in places that you'd rather it not?

I'd really like a bit more overhang than that for most purposes. At first, the overhanging part serves as a softer presentation of the abrasive. After a bit, the paper wears in and wraps around the edge of the pad, and that helps in cleaning flutes.

The only time I trim them up close is to get into places like hems, where I don't want the paper working on the hem while I'm trying to get at the surface of the plate. Trimming also keeps the paper from catching in outward turned hems if they are not set down so well as they might be.

Ckanite wrote:Also, my last post wasn't supposed to be too serious, just poking a bit of fun at the idea of you not sharing as much information as you could because you weren't sure 100% sure about it.

I understand that you were just rattling my cage a bit. That's good. I need that sometimes. When I said that "we all need to grow a pair", I meant me too.

I have not been posting the details of my finishing activities as thoroughly as I did the shaping work. Part of that is because it's not that exciting or photogenic. Part of that is that I have been trying to spend more time doing, and less time documenting. Part of it is that I have just been wrestling those demons in private so that I looked more like I knew what I was doing in public. I'll try to document a bit more.

Mac

Mac

Sean Powell wrote:I had a near disaster this holiday when the cats spilled a pitcher of water intended to water the X-mas tree. The water leaked through the floor and rained on my workshop splashing a number of tools. Thankfully the rust came off with scotchbrite and I didn't need to kill the cats...

I'm glad you didn't have to slay the kitties. That's so hard to explain to the rest of the family.

Sean Powell wrote:So I'm watching this thread and it got me thinking. All this work polishing and it could be months before the polishing is complete. The environment is not kind to steel, even in the dry of winter. What do you do AFTER polishing to preserve the finish until you do the final blackening or final hand-polish before delivery?

The armor is currently in an intermediate state of polish. I expect to go back over everything with a cotton buff to "color" it a bit. I may use a bit of simichrome on it as well.... we'll see. In any case, I will have something on the surface while it awaits the blackening. If that proves insufficient, I'll slap on some WD40.

I'm having pretty good luck with the rust thing at the moment. I keep the shop heaters on so that the temp doesn't fall below 50°f or so at night, and all the weatherproofing around the doors is keeping out the humidity when it rains. The worst rust problem I have had is apparently my own fault. Once in a while (out of desperation) I rinse my hands in the slack tub, and I managed to splash a couple of drops of water on the sabatons on my way past the armor stand. It took me months to figure out what the problem was.... I'll need to take a few places back a grit or two to level out the pitting.

Mac

Scot,

Thanks for the tip about the Cratex wheels! I have one in the shop, but it is very fine and I've never found a use for it. I will look into getting a coarser one to try.


About grinding in general....

I am confident that it is a demonstrable fact that a firm abrasive will level an irregular surface faster and with less removal of material than a yielding abrasive. It does this spanning the valleys. By contrast, a yielding abrasive will take material out of the valleys before the hills have been reduced. By the time the hills are gone, the valleys are deeper, and thus you have to remove even more material.

If you are using thinner stock than I am, then you need to be even more concerned with this.

Also...
Consider putting the flutes in after the planishing is done. It's really the best way in almost all cases.

Mac

You might have explained this already, but I would be interested to hear why you and your client decided to blacken the harness. Surface finishes are hard to study, and my own work is focused on the 14th century south of the Alps. I don't know what evidence we have for how fine German armour was treated a hundred years later!

Mac wrote: I understand that you were just rattling my cage a bit. That's good. I need that sometimes. When I said that "we all need to grow a pair", I meant me too.

I have not been posting the details of my finishing activities as thoroughly as I did the shaping work. Part of that is because it's not that exciting or photogenic. Part of that is that I have been trying to spend more time doing, and less time documenting. Part of it is that I have just been wrestling those demons in private so that I looked more like I knew what I was doing in public. I'll try to document a bit more.

Good! And finishing might not be as sexy or as photogenic but that's what I need the most help and info about. Seeing as to how you're so unsure goes to show how little information there is about the subject. It's not really talked about that much. I'm sure it has a lot to do with how drab of a task it seems but I think it also may be due to people trying to hide their secrets about "their" look. Everyone will tell you how and where diamonds are mined. Very, very few people will share how they're polished.

Also, if you have any demons you're wrestling with, feel free to message me.

Back on Pages 38-40 of this thread Mac went into detail about some of his abrasives their use and setup. It would be a good time for those following along to go back a reread these

Truing up edges on grinding disks was also covered earlier on page 12 in this post: set up for truing wheels

Here is an example of why you should reread these pages: (link to full post quoted below)

Mac on Page38 wrote:The other thing I want to say is about finishing processes in general. Many folks will tell you that the key to getting a good finish is in not skipping over any of the grits. They would have you go dutifully from one to the next... 80gr-120gr-180gr-220gr-280gr-320gr-400gr-600gr, and then on to a series of polishing compounds.

I have to disagree. The vambrace plate above has had the following treatment.....
--three passes at different angles of an 80gr belt, backed with a firm platen to remove the hammer marks and level the surface
--one pass of an 80gr belt, backed with padded platen to remove the facets from the firm platen passes
--one pass under a slack 80gr belt to blend the surface a bit more
--two passes at different angles with 320gr

The 320 is in the form of 1" aluminum oxide strip on the cylindrical face of a 12" MDF wheel. There is a layer of felt between the MDF and the sanding strip. I'll show pics of the wheel later.

I am not sure where I will go from here, but I certainly will not introduce any steps between 80 and 320.

Hi,

I'm afraid I am the guilty party who is the cause of all this by commissioning the armour from Mac... Well, a long time ago! As soon as I saw the pictures of his work on his website, I could see it stood out from the crowd - but over the subsequent years, and the visits I have made to him in Philadelphia, I have come to recognise what a unique talent he has, and I feel immensely privileged - even humble - that I am to be the ultimate recipient of this armour.

I do follow the blog very closely (I can't help feeling Mac would feel rather discouraged if I, of all people, did not!) and have occasionally commented in our e-mails on some of the things mentioned. Mac has, in fact, encouraged me before to register - if only to help members better appreciate that there is, actually, a living, breathing person that this is intended for! However, I have demurred - forums are not really my thing, and there isn't usually much I can add anyway. I am a computer programmer by profession - the technical details of how Mac weaves his magic with metal is utterly beyond me - indeed, a lot of the time, I don't really understand the questions, never mind the answers!

However, the question has been asked of how a blackened finish was decided upon, and this is one thing I may be able to answer even better than Mac can. Essentially, it is simply personal preference. It has something I have been keen on from the very start, heavily influenced by the Flemish miniatures of the period, although I could only be confirmed in that choice by seeing what Mac did for Toby Capwell (that armour was in his workshop in Malvern (as it was then) when I first visited Mac in 2004 - but still in a 'raw' state - I was 'gobsmacked' when I saw the photos of the finished article).

But that, of course, is Flemish/English practice, and, indeed, I have to admit that were we to follow the statue exactly, the armour should be of polished steel with a significant amount of gilding. However, I have found quite a few images of 'black' gothic armour in the contemporary artwork. There is, for instance, a painting of two saints in 'black' gothic armour in Augsburg Cathedral (and they ought to have known what armour looked like in Augsburg...). I have also come across a miniature of St. Florian, no less, in a broadly similar armour, and I have suggested that one in particular as a suitable model (knowing the issues involved, I'm not going to try posting these images, but if you ask Mac nicely, perhaps he would oblige), but there is a source even closer to home. One of the panels on the back of the altarpiece in St. Wolfgang is a depiction of St. Hubert, and in that he is shown wearing 'black' armour. Therefore, whilst we might not be being true to the statue itself, we do have a source for 'black' armour from the same overall work by Michael Pacher. Anyway, that's the argument I have used with Mac! The choice of the statue of St. Florian, by the way, was from a 1930s article by Sir James Mann I found in the library at the Royal Armouries, after Mac suggested using a contemporary artwork rather than a (probably messed around with) surviving armour as our model.

Anyway, I hope that helps to answer the question. Having explained that (I hope) I am now more than content to return to the shadows. Before I go, however, I will add that in addition to the armour that Mac has been making, I have commissioned some items from Arms & Armor in Minneapolis, and, in addition to returning to Philadelphia to collect the armour in person - when I have been left in little doubt that I will be engaging on a short-lived modelling career - I have made plans for my own photoshoot - with both arms and armour together - at a late 13th c. farmhouse in the English countryside (now a holiday let) once everything arrives in the U.K.. I will, of course, let Mac have copies of anything worthwhile that might transpire (I used to say 'We'll have to see what develops' - but that joke doesn't work very well these days...), and no doubt he will want to share them with you in due course.

A.P.

Hi August.

You are more than welcome to stick around, we can always use more programers here (I'm one too). I'm looking forward to the photo shoot.

Thank you very much A.P. for chiming in! I was half wondering if Mac was secretly making this for himself Personally, even though it's more work to maintain, I love a black and gold finish. It's just looks both intimidating and classy. And please feel free to add your own comments from time to time! It would be nice to hear an outside perspective from time to time. I've noticed that we tend to geek out about the smallest and strangest details.

Please, please, pretty please gild couters and poleyns!

Hey Mac! I always appreciate all your, and everyone else's, thoughts of grinding and polishing, even if I have a hard time wrapping my head around a lot of it. I probably do 90% of my finishing work with sanding disks mounted a 4 1/2" rubber backing pad stuck in my drill press. So clearly I need a lot of help.

I'd be interested in hearing a bit more about your fleet of backing pads. Where did you get them from? What size are the threads on there?

Thanks A.P. Those Flemish illuminations do have a lot of dark armour.

I hope that someone sits down and does the archival research there, because I am sure that the Flemish towns have just as much as the German ones (let alone the Italian ones which nobody outside of Italy seems to have tackled!) Yes, they have had a few armies rolling back and forth since then, but the South German ones had to deal with Bomber Command and the US Army Air Force, and they weren't kind to archives either.

A few modelling sessions are in my near future too. Innsbruck has some nice backdrops or I could go all the way to Hall in Tirol.

For what it's worth polishing is one of my favorite steps. I may be part magpie, but shiny is so appealing. The process is kind of repetitively soothing and it makes a piece look done, much like a good press on a sewing project.

It's very nice to learn new nuances and professional details through your process. Thank you for sticking with the documentation process and answering all the questions.

Hi August!

Thank you for your patronage of not only a great armorer, but the edification of a bunch of mini ones too. It's really interesting to hear your perspective too especially as it is getting closer to completion.

I've still got my head down near the grinder. Things are progressing, but there's not much to report.

I think I've got the set up wheel problem under control. It looks like a couple of hours in the range at 120° f or so helps the adhesion considerably. Next time I need to set one up, I'll get some pics of the process.

Mac

Mac wrote:I think I've got the set up wheel problem under control. It looks like a couple of hours in the range at 120° f or so helps the adhesion considerably. Next time I need to set one up, I'll get some pics of the process.

Mac

I would think so!

Hmmmm, that range of mine is looking handier...


It's been neat to see your grinding/ sanding process. Flutes (and other armour shapes) have bred some creative solutions to consistantly process them sucessfully. Glad I am working on 16th century stuff, though my engraving is lacking!

Sanding is always a good way to sharpen up lines-but I have to start with thicker material. I get variable speed sanders for this stuff. Coarse grind of welds is about 50 grit zirc usually. Secondary is 150, then I go to 220 and finish before buff with 400.

Buff is a sisal with a combo of green and stainless compound. That gets it to about a 600 grit finish,coarse satin. Cloth wheel with just green compound will get it to a mirror-though you have to go back and get missed scratches from the sanding at times. I use hook and loop discs to sand. I got tired of the things flying off across the shop-and having to clean melted adhesives from my work.

Bender,

Thank you for the synopsis of your grinding processes!

Do you use the green compound and the stainless compound together?... of the same sisal wheel?! ... or first one and then the other?

Mac

Tableau wrote:Hey Mac! I always appreciate all your, and everyone else's, thoughts of grinding and polishing, even if I have a hard time wrapping my head around a lot of it. I probably do 90% of my finishing work with sanding disks mounted a 4 1/2" rubber backing pad stuck in my drill press. So clearly I need a lot of help.

You know... I started out with an arrangement like that. It was one of these guys, with the head tipped sideways. I still have part of it; the arbor is serving as the jackshaft of my homebuild grinder.

Tableau wrote:I'd be interested in hearing a bit more about your fleet of backing pads. Where did you get them from? What size are the threads on there?

They are the sort of pads one uses on random orbit sanders. The thread is 5/16-24, but you can get them in 6mm-1 as well. They are available in a few sizes, and I have made the small ones by reducing larger ones. I did that by mounting them up and running a small but coarse disc in a dremel tool against them as they rotated. That's a messy job, but it works a lot better than trying to size them on the lathe.

Tom B. wrote:Back on Pages 38-40 of this thread Mac went into detail about some of his abrasives their use and setup. It would be a good time for those following along to go back a reread these

Truing up edges on grinding disks was also covered earlier on page 12 in this post: set up for truing wheels

Here is an example of why you should reread these pages: (link to full post quoted below)

Thank you, Tom!

Mac

Mac wrote:Bender,

Thank you for the synopsis of your grinding processes!

Do you use the green compound and the stainless compound together?... of the same sisal wheel?! ... or first one and then the other?

Mac

I use a combo of both to cut with the sisal. And finish with just green on a cloth buff after stripping the wheel to remove any steel particles that will just rescratch. You need to use one of these every once in w while to clear out debris. The wheel will load up with microscopic particles of metal and you cannot make any progress after a while. The wheel needs to be cleaned with a "rake" periodically.

This tool is also used to true new wheels. https://www.youtube.com/watch?v=-sgp27as2xQ

Traces of compound from coarser buffing processes should be removed from your work with acetone, to avoid contaminating wheels being used for finer finishes with other compounds. It will be almost impossible to remove from a wheel once it is on.

I tried emery once, but it made too many scratches. Polishing can almost double the cost of a piece of armor when time is taken into account.

I usually just use a scotch brite ten inch wheel in my long shaft 3450 1 hp grizzly buffer. It leaves a satin finish, and most people who want bright finishes are happy with it.

Where is the best place to buy scotch bright pads?

RandallMoffett wrote:Where is the best place to buy scotch bright pads?

McMaster-Carr has a full selection (grits) of mesh sanding pads
https://www.mcmaster.com/#sanding-pads/=15u5db0

Thanks Chris! I will have to get a few when I get my next batch of rivets.

RPM

Here's a quick look at the last few day's work.

There were places on the flutes that were too tight to get at with a large sanding disc....



....so I used this small pad with 180gr cloth discs. They have a sort of ragged edge because they used to be "wavy edged" discs. Unfortunately, they would not stay on the backing. The manufacturer has used a cheesy "loop" fabric that will not grip. I found that cutting the waves off reduced the leverage the pad had on its attachment enough to make them usable.



This is the operator's eye view of the process.



The 5" wavy 180gr discs turned out to work very nicely on the larger areas of the flutes. This is exactly why I bought them, but somehow I had forgotten about them till now. The wavy edge is great for blending, but an absolute pain in the ass if I get too close to an edge. The waves catch very easily, and that almost always ruins the disc. It does not do much for my composure either. The shredded discs are piling up, waiting to be trimmed down for a smaller backing pad.



Everything that could be done with the 220gr set up wheels was done that way.



This is what the transition from the 180gr belt to the 220 set up looks like. It does not sound like a big jump, but the belt's are on very stiff cloth and the set up is very soft. The grit numbers are not nearly as important as the presentation.



Then the surfaces were all taken to the Norton 8-A-medium wheel.



All the parts as they sit waiting to go to the buffing wheel.




I was having some trouble with my machine slowing down. It turned out that the power-twist v-belt from the motor to the jackshaft has stretched over the years and the motor platform was sagging until it sat against the framework. I removed two links, and all it better.



The armor looks a lot nicer with the pauldrons in place. Two nights ago, I kept waking up with the thought that I could actually see the end of this project. It's the first time I have had that feeling.



Yesterday, I started the rough grinding on the vambraces, and expect to have that done this afternoon. Then it's on to the 80gr. discs.

Mac

Mac wrote:The armor looks a lot nicer with the pauldrons in place. Two nights ago, I kept waking up with the thought that I could actually see the end of this project. It's the first time I have had that feeling.

It certainly seems to be coming together at last, and wonderfully at that. However, it's the finishing touches that really provoke a feeling of "completion," and I'm excited to see it assembled with all of the straps, buckles and other accessories in place. One can almost begin to imagine that at this point... Vivat!

-Gerhard

Mac, even though I could reasonably imagine the details as your explained them and looking at your machines, THESE were the details and shots I was looking for! They really help clear up a few ideas I had about finishing. Thank you!