Greenwich Buckhurst armour

[James Arlen Gillaspie]

I am freshly back from the Winter Antiques Show down in NYC, and Peter Finer had a magnificent pair of Peffenhauser pauldrons up for sale. I have been thinking for awhile about how to duplicate the appearance of fire gilding, and seeing them makes it fresh in my mind, once again, seeing as I have not had any gilded work in the shop for awhile. It helps a lot to see such top notch work inches away (no case), especially as I am extremely nearsighted, and with my glasses off, I can see things most people need a loop to see. While some fire gilt things, especially pistol barrels, are burnished, producing a surface much closer to the appearance of electroplating, most of that on armour is not, and has a somewhat frosted appearance, probably due to the finely ground particles of gold that made up the mercury amalgam. It seems to me that blasting with microbeads might approximate that effect, but I could not suggest how big the beads should be.

[wcallen]

I expect Finer's price was magnificant too. If you have a picture and/or price I would love to be entertained.

Wade

[James Arlen Gillaspie]

Sorry, I took no photos. I did take note of the price, but I don't recall it. I believe it was in excess of 100K if memory serves.

[Jason Grimes]

Years ago I had experimented on using PMC gold clay to try and get a more amalgam type gild. The issues I had was that the temp required is far above what you need for tempering so you would have to harden/temper after application. The other issue was getting it to stick but that might be able to be resolved?

[wcallen]

Sorry, I took no photos. I did take note of the price, but I don't recall it. I believe it was in excess of 100K if memory serves.

I found them on his web site. Nice, but Peter Finer prices are a bit out of my league. In this case, a lot more than a bit.

Wade

[Chris Gilman]

I stopped by Finer's place in London once last year and I was stunned at the prices they was asking. I saw the piece I think you are talking about and yes, it was 100 or 200K. (Pounds)

James,
The issue I am having with the electroplating is depth of color. The fire gilding color is so much richer. The texture is so faint on the Greenwich it is almost unnoticeable. But the color is, and even with obsessive plating, the color isn't getting there. Plus, the time I spent plating the most recent sample, which was getting closer, was, I'm guessing, 30 to 40 minutes. If I attempted the whole armour in this manner, I'd never finish it.

[coreythompsonhm]

What are the requirements of the fume hood to safely handle mercury guilding?

[Mac]

What are the requirements of the fume hood to safely handle mercury guilding?

I don't know what the legal requirements are, but here are the practical ones....

--The hood must be designed so as to accommodate what ever sort of heat source you are going to use to evaporate the mercury.
--The exhaust must be arranged so that all the fumes will pass through some sort of filter that will extract the mercury fumes.
--You must either be able to clean the apparatus completely when you are done, or be able to enclose it in something to contain the residual mercury in between uses.

And here is the moral requirement...
--You need to find a safe way to get rid of any residual mercury that can not be reclaimed.

Years ago, I helped someone gild some copper alloy parts. We built a hood by taking the bottom off a 5gal glass carboy, and setting that up over a propane stove. A water powered venturi sucked air out of the top of the carboy and through a series of 3 water bubblers made of Erlenmeyer flasks, rubber stoppers, glass tubing. Tygon tube connected all the parts.

This apparatus worked pretty well. When we tested it by evaporating a small quantity of Hg, and measuring what we recovered in the bubblers. We were able to account for almost all of it. And there's the rub. Some of the Hg may have passed through the traps as vapor, but I don't think it very likely. The first bubbler trapped nearly all of it, and the second and third bubblers were pretty clean. I think the missing Hg was in the form of the gray film in the inside of the carboy and tubes. This is what leads me to say that you need to be able to adequately clean the apparatus or to encapsulate it between uses.

If I were doing this again, I would probably fall back to only one bubbler, but follow it with a chemical scrubber. I believe that finely divided sulfur would do the trick. Of course, that leads to the question of what to do with the resulting mercuric sulfide.

The other thing I hasten to point out is that you need to be careful when milling the gold into the mercury in the first place. We used the mill that is described by Theophilus. It worked fine, but I was not at all convinced that the person doing the milling did not let some little globules of Hg escape onto the floor where they may still be outgassing. So.. you would need to develop a protocol that will properly contain anything that gets out of the mill.

Mac

[James Arlen Gillaspie]

I have often wondered why 24 K gold plating looks more like 14 K. Then I thought about the visors on space helmets that have a gold coating two millionths of an inch thick, and it occurred to me that typical pen plating could be a bit translucent, even though it is much thicker. I wonder if plating with copper first would make it a bit more red.

[Chris Gilman]

James,
You are correct that the plated gold it thin enough to allow the base color to effect the overall surface color. This is one of the reasons why silver or nickle is deposited over the copper "primer" before applying gold. My understanding is, copper naturally will be deposited much heavier than the gold, and that the gold, being so thin, will eventually be absorbed by the copper.

[James Arlen Gillaspie]

Hmm, yes, I wasn't thinking about the absorption problem.

[Chris Gilman]

I've done some more tests and it seems the bone charcoal is pulling more of the copper away from the surface, or at any rate, it makes cleaning the copper deposit off the steel much easier between etches. It also seems to allow for longer etch times with greater affect. The bone charcoal I have has a slightly larger grain than table salt.
I've completed the right greave front plates and used the bone charcoal mix for 3 hours and it seemed to etch effectively.
My ratio for these tests was 4 parts CS - 2 parts salt - 1 part bone charcoal -1 part 15% vinegar. I put the powdered components in a bucket with the snap on lid, then shake to mix thoroughly. Then add the vinegar and shake again. Let sit for 1 to 2 hours, shake vigorously again. 12 to 24 hours later, the paste is like guacamole. With the charcoal, age does not seem to effect the paste's etching rate noticeably.

I have made some tests with smaller, more consistent dots and these are looking much better. Although, I now see I have the dots too dense.

Bluing: The study that was done of the Buckhurst's color, concluding it was steel exposed to atmosphere at 250 c, this temp does not seem to work, with the technique I'm using. In the salt, at 250 c (482 f) the color was very pale straw, barely perceivable. It wasn't until 300 c or 580 f that it shifted to blue. I got an amazing color and the pen plated gold got a little yellower, not as orange as the previous test at 650 f. The photo doesn't show the gold as well as it looks in person, but, it's still "weak". Mac has pointed out that over time (unknown duration hours or weeks) the blue color may be achieved at the 250 c temp. But in the salt, the color was reached in a minute or so at this higher temp and seemed controllable. Of course, this mean a very big container of 500 degree salt for the breastplate and such. The heat treat company may have a tank with a material I can use, if they are willing.
There is a little bit of spotting, which I believe was surface contamination. The surface is also sensitive to finger prints, even with two coats of paste wax.



The test here was pen plated with 24k gold and I was not thinking and forgot to wire brush, per Mac's advice, the etched areas before plating, resulting in the background areas being a bit gray. The pen plating is still paler than the real armour, but, it does shift a bit in color with the bluing, and gets a touch richer yellow, which is desirable. I'm still on the fence about fire gilding.

Since the real armour shows no signs of gold on the background dots, this means they were either blue, like the rest of the bare steel, or had been cleaned off to be silver. After gilding, I cleaned off an area of dots, in the upper left and let the dots turn blue. The effect in my opinion was a bit drab looking, so, rather hastily, I sanded the blue off to see the effect. I think I like the silver dots.

[Mac]

This product line has just come to my attention.

So... if you don't feel like wearing your steel legs all the time, you can still have that Greenwich look.



Mac

[Chris Gilman]

Pretty cool.
I need to wear hose under the armour, would these be too much?

[Chris Gilman]

I finished etching the right greave. While I'm happy with the improvements in artwork and scale of the design elements, I'm still not completely happy with the consistency of the etching, nor the ultimate depth I'm getting. There is some variables I have been unable to pin down.

Here is a good look at the progression I've made with the quality and neatness of the artwork and the gold plating. (Old to new - left to right)



To address the etch depth and consistency, I thought I would do a formula test. I made three different formulas of etch paste (by weight):
#1- 20 grams of Copper Sulfate / 60 g of salt
#2- 40g C.S / 40g salt
#3- 60g C.S. / 20g salt

Then after thoroughly mixing the two powders together, I split these into two sets. To one set I added 15g of bone charcoal to the 2nd set I added 30g of bone charcoal. The 30g set I labeled "A" (1A, 2A, 3A)
To these 6 batches I added 15g on 15% vinegar and mixed.
I had final mixtures of:
#1- 10 g C.S. / 30 g S. / 15g B.C. / 15g V.
#2- 20g C.S / 20g S. / 15g B.C. / 15g V.
#3- 30g C.S. / 10g S. / 15g B.C. / 15g V.
#1A- 10 g C.S. / 30 g S. / 30g B.C. / 15g V.
#2A- 20g C.S / 20g S. / 30g B.C. / 15g V.
#3A- 30g C.S. / 10g S. / 30g B.C. / 15g V.

After 2 hours I remixed and let them sit for 12 hours. I then remixed them a final time and applied them to the test plate.
As the bone charcoal has consistently reduced the metallic copper deposited on the surface of the steel, I decided I would do this test as long duration etches. (verses 1 hour, then clean, repeat).





The first was 7 hours & 20 minutes. I cleaned off the paste and noted the damage to the resist (vinyl & asphaltum resist)


I used an older vinyl resist sheet (orange) that had some dots on it, so I left these and just added asphaltum dots to some of the surrounding area. You can see 1, 1a & 2a retained dots better than the other areas.
I then did a second etch for 16.5 hours. this time all of the resist, both vinyl and asphaltum was failing. I cleaned the surface and gave a lite sand to the high points with 600 grit paper. While the etch depth was good, the results were frustrating, as I did not see very much difference in the etch depth, which I was expecting given the wide range of ratios I had used.
I cut the piece in half to see if I could better see a difference in etch depth, but not really. The only noticeable thing was background coarseness, due to the large quantity of bone charcoal which is coarser than the other ingredients and of course does not dissolve in vinegar.



I'm going to do another test with the same C.S / salt ratio, but this time use different charcoal, wood and powdered Also 10g of bone charcoal, 5g and 0 bone charcoal.

[Indianer]

A) I conclude, these two formulae did the least damage to the vinyl sheets and asphaltum dots:

#1- 10 g C.S. / 30 g S. / 15g B.C. / 15g V. (15%)
#1A- 10 g C.S. / 30 g S. / 30g B.C. / 15g V. (15%)

B) The two mixtures did not show very much difference in the etch depth.
C) A larger bone charcoal content did produce a noticeably coarser background.
D) Wood based charcoal did not seem as effective as the bone charcoal in terms of the aggressiveness of the etch.

[coreythompsonhm]

Chris,
Ugo and I tried it out just for the hell of it because why not. First test of CS, Salt, and vinegar was a really course background. We noticed that the cs crystals that did not dissolve in the paste tended to cause the courseness. We went and got a cheap coffee bean grinder (dont fill to the max line btw....) and ground the CS and salt to a fine powder, close to a flour consistency. The results in background quality were impressive. If I was to try a charcoal additive to aid in copper deposit prevention, I would grind the charcoal to a fine powder as well to maintain the consistency and even mixing of all ingredients, as they would be of the same particulate size (roughly). I found that the main cause of resist disturbance was the removal of the metallic copper deposits.

[Chris Gilman]

Cory,
If you look a couple of posts up in this thread, I posted a mixing approach which solves the coarseness of the paste, with no need to grind the components first, since the copper sulfate and the salt both dissolve in water (or vinegar). The Bone charcoal only caused the graininess on this test, because of the high percentage used. In my other pieces, I used a much smaller proportion of Bone charcoal and it had no graining effect. I also used wood charcoal, ground up, and it did not seem to prevent the copper build up as effectively as the bone charcoal. I chose to use the much higher amount to see if it would affect the etch depth.
Something I did not post (I forgot I only discussed it with Mac) is that on one of the greave pieces, I had some tiny areas that etched 3 to 4 times deeper than the surrounding area. This was on a single piece, using the same batch of paste and the areas were places within the overall paste applied surface. Since the paste is opaque, and I didn't notice this until the part was thoroughly cleaned, I did not know if this was due to a concentration of one of the components, extra charcoal near the surface or something else. This is the reason for the much higher concentrations of the different components.

The interesting thing here, is the etching was pretty consistent across all the formulas, even with the paste that had ratios that were opposite of the ones suggested in the period sources. That is; 1 part copper sulfate to 3 parts salt, where the period recipe is 2 parts C.S to 1 part salt. I'm just annoyed with myself, that I didn't take more notes of the tests early on. I had no idea it would be this tricky to isolate the best performing mixture.

Indianer,
I have tried wood based charcoal and it did not seem as effective as the bone charcoal. I only tried the bone charcoal after my brother mentioned it was prized for it properties when case hardening gun parts in the 19th century. When I did some research, I found where it had been used to absorb excess copper from contaminated water and was very effective. Now, I only did one or two tests with the other charcoal, and in minor amounts. This recent test was to see if a large percentage of the charcoal effected the aggressiveness of the etch. Until I do some other tests, I feel this question is still unanswered.

[Chris Gilman]

With the AA going down, I didn't want to loose my notes on this project, so I have chronicled the project on my blog and have just uploaded the latest info and progress.
http://diligentdwarves.blogspot.com/

If I have some time this evening, I'll repost it here. (Takes time because I have to edit all the image files to meet the AA image size requirement, and upload them to my server.)

[Chris Gilman]

Here are a couple of updates on the etching:

Etching on the legs are done. Here are a few shots









The gauntlets have so many pieces, 100 when you count all the finger plates, I had to come up with a convenient way of storing / holding them for the masking & paste applications. I used a section of PVC pipe, with magnets taped down at intervals along the length. Then for when I was masking the pieces, I made a simple hook bracket to hold the pipe above my bench.
The etching was done outside at my deep sink, so I could rest the pipe on a couple of chair backs.
Here is the bench set up:



Then the finished gauntlets. Etch times for legs and gauntlets were 4 etches at 90 minutes each.



I feel there is still some variable in the effectiveness of the paste, which I have yet to pin down. The cuisse's etched deeper than the gauntlets and the times were the same.
I think it is either temperature or moisture content of the paste. Earlier temperature experiments did not reveal any significant difference, so I'll have to do some additional tests.

I am waiting on Jeff to get me the next big batch of parts, so I can send them in for heat treat, but until then, I'm patterning the helmet and buff, to prepare the artwork so when it comes back, I'll have a bit of a "Head start".
Also, I'm doing more tests on heat bluing and gold plating. I've yet to find the exact solution I'm looking for on these. Most especially the plating. The mercury gilding gives a specific look to the gold, and I'm convinced its the texture / surface finish, since the gold goes down so thick.
I have tried a couple of things that look promising, but nothing to show yet.

[Gerhard von Liebau]

Chris, it all looks fabulous! I hardly know what to say, as you're obviously still in the process and I'm well aware of how much work is left to be done... I can only look forward to more updates! I hope things are well, otherwise!

-Gregory

[Ernst]

Dayumn man. That's beautiful already without the gilding.

[Keegan Ingrassia]

Absolutely incredible. Your work never fails to impress, and I can't imagine how stunning this is going to be with the blue and gold.

[Indianer]

Chris, you´ve created true beauty there...
If I may ask about a few details.. my notes seem to diverge from your last post in terms of paste composition. What composition did you finally come up with?

a part {x prts Copper Sulfate, y prts fine salt, z prt (bone) charcoal} to b parts Vinegar

My notes further say:
5 applications of 1hr each, 1 final application for 6 hrs (this undermines the vinyl)

This time you went with 4x90min. What´s the reason for the change? Is there a reason?

Much obliged.
Indi

[Chris Gilman]

Thanks. I'm pretty happy.

Yes, I have been adjusting this. The legs were 90 minutes each etch, in relation to the minimized copper build up I saw with the increased amount of charcoal I had added, when switching from volume to weight as a standard of proportioning. I also reviewed the work that Johnathan Travers did, and I see in his PDF (I'm not sure how I missed this) he added 10% Sodium Bisulfate. Which I have ordered, and will add to my mix to see if it improves the etch depth or amount of time the paste can be left on the metal and still be effective.
I still feel there is a variable in my results with this paste I have not pinned down, and I also feel (No other reason than "gut") that I'm missing something, and this paste should not need to be reapplied so many times.
The current recipe is:
80g Salt
80g Copper Sulfate
20g Bone charcoal (granular)
20g Wood charcoal (powder)
60g 15% vinegar

As I said above, I'm not sure this recipe is optimal, and could benefit from more controlled tests. I'm inclined to think temperature and moisture loss of the paste has a measurable effect.

On the gauntlets, the vinyl stuck perfectly, in fact was difficult to remove. Surface prep was clean with Acetone prior to vinyl application. Then clean with alcohol prior to dot application. Dot (very tiny ones (.5mm)) needed quite a bit of repair. Larger dot, 1mm, seemed fine for the most part.

[Indianer]

Chris, thank you kindly for the details. There´s another thing I wanted to ask: The vinyl. Not familiar with the matter I´m having a hard time figuring out which would be used. It´d be a great help if you could maybe attach a link to the exact product, so I can save the specifications as a reference. Thank you in advance!

Indi

[Chris Gilman]

I have no link, It was a sign vinyl that my local supplier had on his "discount" shelf. I tested a number of sign vinyls and they seemed to be about the same.

[Chris Gilman]

I also reviewed the work that Johnathan Travers did, and I see in his PDF (I'm not sure how I missed this) he added 10% Sodium Bisulfate. Which I have ordered, and will add to my mix to see if it improves the etch depth or amount of time the paste can be left on the metal and still be effective.

Ok, so I tested the Sodium Bisulfate, and its not what you want.
I made a double batch (Formula above), then split it in half, and added 10% SB, to one of them. (by weight of the salt & CS only)

As I'm looking for something to increase the effectiveness of the paste, over longer times, I let the two samples etch for 2 hours, hoping the SB would increase the effectiveness of the paste.

After 2 hours:
Sample #1 - The base formula; Cut as expected, with all the dots coming off, but the vinyl OK.

Sample #2 - The base formula with the 10% Sodium Bisulfate, etched only 1/4 as deep as the base formula and also destroyed all the dots, but seemed to have damaged them progressively, as there were clear signs the circumference of each dot was being eroded inward and in the end, only the very center was bright and unetched. This formula also left a very thick copper layer, that was difficult to remove without damaging he tiny parts of the vinyl.

[Christian Wiedner]

How do you dispose the used paste?

[Indianer]

Just so we are clear - with "dots", do you mean some sort of "asphaltum" dots or small vinyl patches? thx!

[Chris Gilman]

How do you dispose the used paste?

I collect most of it in a tray, let it dry and crush it up and deposit in areas of my yard as a weed killer.

[Chris Gilman]

Just so we are clear - with "dots", do you mean some sort of "asphaltum" dots or small vinyl patches? thx!

Yes, the asphaltum dots.

[Chris Gilman]

For those following the etch process;
I have done a test to determine which resist lasts the longest for the dots. I have been changing the paste every 90 minutes, but I feel 2hrs or longer would still be still effective, if the dots would last. The vinyl seems to last quite well if the steel's surface is cleaned with acetone first. Earlier, I had not noticed a difference between the "Rio Grande" (brand) "Etching Resist" or "Asphaltum Varnish ", but I have been having to repair many areas after only 90 minutes and need to understand what's going on. Part of the issue may be the actual armour had a different finish than the test plates, thus improving the vinyl adhesion, but degrading the dots durability. (The vinyl liking a mirror surface and the "paint" wanting a bit of "tooth")
I have a number of books on jewelry making I plan on referencing for other resists, but for now, I used what I had in the shop.
For the test, I polished up a sample plate, and put some vinyl decorative boarder down, then added dots of each resist type I wanted to test. The dots were added with a needle bottle with a 25ga. tip (https://www.mcmaster.com/1902t351)

#1 - Asphaltum Varnish (Thinned slightly)
#2 - Etching Resist (Thinned slightly)
(1 & 2 Both "Rio Grande" products)
#3 - Amber Shellac ("Bulls Eye" brand)
#4 - 1:1 mix of Asphaltum & Shellac (Wanted to separate, so I re mixed for a 2:1 ratio)
#5 - 2:1 mix of Asphaltum & Shellac
#6 - Rustolium High Heat paint (I bought this to see if it would survive the bluing heat, which it does)

1st etch - 90 minutes
#1 - No loss
#2 - 2 dots lost
#3 - No loss
#4 - No loss
#5 - No loss
#6 - No loss

2nd etch -90 minutes
#1 - 7 dots lost
#2 - 90% loss
#3 - No loss
#4 - No loss
#5 - No loss
#6 - 95% loss

3rd etch -120 minutes
#1 - 90% loss
#2 - Masked off
#3 - 4 dots lost
#4 - 90% loss
#5 - 4 dots lost
#6 - Masked off

4th etch -150 minutes
#1 - Masked off
#2 - Masked off
#3 - 90% loss
#4 - Masked off
#5 - 10% loss
#6 - Masked off

I painted the whole plate, then block sanded the surface with 1000 grit, then 2000 grit.
Results:



The clear winner was the 2:1 mix of asphaltum and shellac. In the painted sample you can see the depth from the 4 etches on three areas; 2:1 asphaltum / shellac mix (Right hand edge "MIX"), the shellac (Front -left) and the vinyl (lines & vines). The others, the paint has filled in the background almost completely and if not block sanded, the paint would have come out. (I have been solvent cleaning the paint)

I also noted how well each resist worked while applying.
#1 - Asphaltum Varnish (Thinned): Easy to control dot size, had to squeeze bottle too much, in the future use larger tip.
#2 - Etching Resist (Thinned): Easy to control dot size, had to squeeze bottle too much, in the future use larger tip.
#3 - Amber Shellac ("Bulls Eye" brand): Dots "flowed out" a bit, making it harder to contrl size. Also, was difficult to see due to amber / transparent color.
#4 - 1:1 mix of Asphaltum & Shellac: Wanted to separate, resulting in "blobs" of asphaltum in center of dot. Inconsistent.
#5 - 2:1 mix of Asphaltum & Shellac: Better control, easier to dispense, easier than thinned asphaltum alone. Still wanted to separate a tiny bit, could be mixed better, or heated slightly while mixing)
#6 - Rustolium High Heat paint: Very controllable, dot size consistent, bottle squeeze minimal.

If anything looks promising with recipes I find in my books, I'm going to do another test or at the very least, another with this shellac/ asphaltum combination, perhaps experimenting with different mixing techniques.

[Igor of Maguar]

Merry Christmas!




Sorry, but reading "Buckhurst" my mind always outputs "Bockwurst"

[Chris Gilman]

I have been working on etching the last pieces and getting them gold plated.
Here is where the project is at the moment.
All pieces are etched (The spurs will need to be re-etched to make them deeper)
Gauntlets, cuisses and right greave / sabaton are plated.
I have the left greave / sabaton to plate, and the hinges and spurs.
Bluing will happen when I have all current pieces plated.

The process to plate each pieces is:
1. Using a very fine stainless wire brush (wheel on bench grinder) clean all etched surfaces in all directions. (in 45 degree increments)
2. Clean with Acetone & Paint background around dots & boarder lines with high temp black paint. (good for 750 f)
3. Wet sand piece with 600 grit to remove paint and refine dots. (This does remove some paint from the border lines, which I'll touch up later)
4. Wet sand piece with 800 grit.
5. Use nail polish to mask boarders & dots. (So they do not get nickle or gold plated)
6. Use a hot (130 f) electro cleaning solution at 7 volts for 20 to 30 seconds per 1/2 sq. inch.
7. Add nickle surface ("Woods nickle strike") at 7 volts for 20 to 30 seconds per 1/2 sq. inch.
8. Add 24k gold at 4 volts for for 20 to 30 seconds per 1/2 sq. inch.
9. Lower voltage to 3 volts and add another pass with the gold.
10. Clean off nail polish with acetone (does not effect black paint)













I ran out of room on my workbench, so I now have a proper way to store the pieces:





After I finish the plating, I'll need to assemble these pieces. This involves, capped rivets, articulating leathers, lining strips and linings. The Almain Armourer's Album shows some of these armours with what looks to be decorative boarders of rolled fabric. (not piccadills) These may have been only boarders, or completely lined. Either way, they need to be sewn to riveted in lining strips. I was planning to use leather, but the photos of A62 show a woven tape around the borders of many pieces. So I'll need to look up the AA thread that Mac talked about woven tape material. (Or, if he reads this perhaps he can add some info.)
I have ordered proper custom 16th Century gloves and some oil tanned buff for the straps from England.
To hold these in, I'll need 2 sizes of capped rivets, and lots of them. Although it is interesting to note that the real armour seems to use mostly brass rivets. I suspect these could be replacements.
Dr. Capwell was nice enough to measure the caps on the real armour and they averaged out at 11mm & 8mm
I found some mass produced brass domes that seem to work very well. They unfortunately are only available in 8mm & 10mm
Since they are already punched, these are a little tougher to solder than the ones Mac made, but I think with some more tests, I can modify Mac's method to find a satisfactory solution.



While the 10mm look pretty good, I have some shallow 12mm domes on their way and I think I can dome these further with my dapping set to make them deeper and closer to 11mm.