Painting a ships hull with a copper and green look paint

[DaveBaxt]

On 1/25/2023 at 10:22 PM, robert952 said:

Great collection of information.  Thanks to all who added to the thread.  

 

(Hit submit too soon.)

 

Was copper applied to rudders (particularly the bottom edges) on small boats to protect them some from rocky bottoms?  It would make sense.  I may be dreaming that I read something on this use of copper on rudders.  However, I may be misremembering.  

 

The foil and painting tricks here may be useful to know. 

I read something similar too but I think it applied to the first parts that were coppered on ships. I will try and did it out but pretty sure it was in Brian Levery's book 'The arming and Fitting of English ships of war1600 to 1815. I will check out if there is anything about coppering small boats. Definately an interesting idea though.

[Bob Cleek]

On 1/25/2023 at 2:22 PM, robert952 said:

Was copper applied to rudders (particularly the bottom edges) on small boats to protect them some from rocky bottoms?  It would make sense.  I may be dreaming that I read something on this use of copper on rudders.

Sacrificial wood chaffing strips have long been used on boat bottoms to protect them from rough landings. Lead, and I presume copper, have been employed for the same purpose, but metal, particularly lead, has the downside of adding weight. As for rudders, however, most, if not all, landings would have been done under oars which provided better control than a rudder in any event and if there was any concern of damage to the rudder, I expect the rudder would have been unshipped prior to landing. All that takes is to lift the rudder off the gudgeons. Rudders were routinely shipped when the boats were stowed aboard or hung in davits. Moreover, landings were planned to the extent possible to avoid rocky areas that risked stoving in a hull what might come down on a rock in the swells. These are just general assumptions made in light of basic seamanship considerations, mind you. I don't profess to be an any sort of particular authority on period small boat handling.

[DaveBaxt]

On 1/25/2023 at 10:22 PM, robert952 said:

Great collection of information.  Thanks to all who added to the thread.  

 

(Hit submit too soon.)

 

Was copper applied to rudders (particularly the bottom edges) on small boats to protect them some from rocky bottoms?  It would make sense.  I may be dreaming that I read something on this use of copper on rudders.  However, I may be misremembering.  

 

The foil and painting tricks here may be useful to know. 

According to Brian Laverys book.'The Arming and Fitting of English ships of war ' The Boats were covered in Rosin until 1771 and the covered with white lead. That does not mean that some copper was used on ships from other countries or perhaps later than 1800 when Learys book does not cover a later period. perhaps someone more knowlegable (Which there are many) might add something here. Hope this is of any help.

 

[Roger Pellett]

The US Navy coppered the underwater areas of launches and some cutters.  I’m not sure exactly when the practice began, I believe as early as the 1840’s. It ended with the standardized boat program in the late 1890’s.

 

Roger

[Bob Cleek]

7 hours ago, DaveBaxt said:

According to Brian Laverys book.'The Arming and Fitting of English ships of war ' The Boats were covered in Rosin until 1771 and the covered with white lead. That does not mean that some copper was used on ships from other countries or perhaps later than 1800 when Learys book does not cover a later period. perhaps someone more knowlegable (Which there are many) might add something here. Hope this is of any help.

I believe that reference would be to the type of anti-fouling coating that was used rather than any anti-chafing sheathing. The "white lead" clearly refers to white lead oxide pigment paint. (White would be the preferred color for boats' bottoms carried out of the water. The white reflects the heat of the sun and so reduces shrinking planking. Less plank shrinkage means the boats would have to be placed overboard and towed less frequently when voyaging t sea. I'm not sure exactly how "rosin" was used, but I can't imagine it providing any anti-chaffing  protection.

[robert952]

@Roger Pellett @Bob Cleek @DaveBaxt

Thanks for the replies.  I appreciate the input. 

 

As I implied, I thought I read it somewhere.  I have two or three sources to go back through in my library to see if I can find this info. 

 

For some reason it seemed in the context of lighthouse tenders and fishing boats that operated close to rocky shores.  But, memory fails me on the details. I looked in the area I had been perusing in Chappelle's American Small Sailing Craft.  No joy there.  

 

I'll probably come across it when I reread some other article or thread.

 

Thanks again for the input. 

[DaveBaxt]

Ok After getting the hang of airbrushing or at least mixing with thinners ( at least for the acrylics I used )I eventually thought I would try and mix a few colours and come up up with something that might look like a ships bottom with copper tiles whilst the ship was out of thr water. Here are four square tiles all with various  base layers. One or two with a black and another with aged copper and copper.both paints by Dark Star. The MDF was also primed with a shellac based product. The black base coat was also coverd with various copper and applied by airbrush. I then went onto applying several coats of vedigris made by Dirty downs and Vallejo . The Dirty Down Verdigris  was applied neat without watering down and the vallejo  vedigris was mixed with both black and white acrylic to achieve different shades  of vedigris and watererd down quite a bit. this was applied using a sponge and I also in some areas wiped off quite a bit using paper towels. I also applied white paint on its own and again wiped off using paper towels.

 

          After watching several videos I got the idea from this video and quite liked the look of the result.

Although my first results are not as good as the video I am quiter pleased at my first attempt and hopefully I can improve as time goes by.

I am unsure how realistic this looks or how much copper you would actually see but your thoughts would be much appreciated. Best regards Dave

Edited February 9, 2023 by DaveBaxt

[ccoyle]

Looks convincing to me.

[Toolmaker]

Looks good to me too

[Bob Cleek]

You've got it! All those samples look great. I couldn't tell them apart from a close-up look at the real thing. Just remember to consider the scale viewing distance when applying those techniques to a model hull. Look at your samples from a distance to see the difference between close up full-scale and whatever scale your model is and adjust your detail accoordingly.

[DaveBaxt]

5 hours ago, Bob Cleek said:

You've got it! All those samples look great. I couldn't tell them apart from a close-up look at the real thing. Just remember to consider the scale viewing distance when applying those techniques to a model hull. Look at your samples from a distance to see the difference between close up full-scale and whatever scale your model is and adjust your detail accoordingly.

Thanks Bob for your kind remarks. I have been trying to consider viewing distance and these photos are probably taken closer than the viewing distance and without any magnification. So I think further away you see less detail so still unsure  whether correct or not. I have yet to try another tecknique building up layers using washes, only and  I think its called glazing. I think perhaps you can add the glaze to the acrylic paint but could be wrong. An idea which was suggested to me by a modeller who is into war gaming etc. I also thought about just using airbrush teckniques for this alone and see what happens.

           Once again I have a question if I may.I have been considerin the aplication of dirty downs moss and rust products as I been sent some by the mistake from the retailer. I appreciate that copper was applied to the ships bottoms to protect the wood  from worms and wondered how effective it was as an anti fouling and whether or not this was actually effective once the patina effect had taken hold. I also remember reading somewhere that this patina effect  was only there whilst the vessel was out of the water and was generally removed by erosion.when moving along in the salt water. Less effective in rivers with fresh water perhaps?  I also understand that after fitting the copper plates that the iron nails in salt water caused serious problems with electrolosis and caused the nails to almost disapear, a kind of sacrificial anodes if my chemistry is correct. Such is why today they use  sacrificial anodes to protect the steel hulls. Therefore my question is would it be prudent to show some signs of rust and moss among the verdigris  or again wonder if this would be too much detail.

                    So I still have some way to go with experimenting but I am enjoying the journey and thanks once again for your help and patience. Best  regards Dave

[Bob Cleek]

4 hours ago, DaveBaxt said:

Therefore my question is would it be prudent to show some signs of rust and moss among the verdigris  or again wonder if this would be too much detail.

You have to consider the "scale viewing distance." How far back from the full-size vessel would you have to stand to see the entire vessel from stem to stern. Measure something the length of the vessel and get the number from that. Then do your "full-size" test panels as you have and stand as far away from them as you would have to stand off from the full-sized model to see it all at one time within your field of vision. Reproduce what your full-size test panels look like at the "scale viewing distance" above on your model's hull. Don't expect to see anything near the detail you've got at full-size viewing distance up close.

 

I doubt copper plates were ever fastened with iron nails. If they ever were, you can bet it wasn't for long for the reasons stated. Copper plates were fastened with copper "tacks," much like copper flashing on a roofing job. The iron electrolysis problems with coppered bottoms involved the iron fastenings of the ship's hull timbers themselves. Signs of rust wouldn't generally be a major visual feature of a coppered bottom. 

 

Weed growth was little deterred by copper sheathing, although continual sailing scoured the bottom pretty well. Weed growth was (is) most pronounced around the waterline where the sunlight penetrates. Weed growth diminishes as the turn of the bilge is reached and the hull surface is shaded by the hull above. When a vessel is hauled, this weed and algae growth is immediately removed by hosing or scraping, which is easily accomplished. Once it dries, it is much more difficult to remove. In tropical waters, bottom fouling could quickly become excessive, particularly if the vessel was not actively sailing for any period of time. Ships were generally careened whenever possible, even if just upon shore, in order to maintain a much faster and maneuverable vessel. 

[DaveBaxt]

3 hours ago, Bob Cleek said:

You have to consider the "scale viewing distance." How far back from the full-size vessel would you have to stand to see the entire vessel from stem to stern. Measure something the length of the vessel and get the number from that. Then do your "full-size" test panels as you have and stand as far away from them as you would have to stand off from the full-sized model to see it all at one time within your field of vision. Reproduce what your full-size test panels look like at the "scale viewing distance" above on your model's hull. Don't expect to see anything near the detail you've got at full-size viewing distance up close.

 

I doubt copper plates were ever fastened with iron nails. If they ever were, you can bet it wasn't for long for the reasons stated. Copper plates were fastened with copper "tacks," much like copper flashing on a roofing job. The iron electrolysis problems with coppered bottoms involved the iron fastenings of the ship's hull timbers themselves. Signs of rust wouldn't generally be a major visual feature of a coppered bottom. 

 

Weed growth was little deterred by copper sheathing, although continual sailing scoured the bottom pretty well. Weed growth was (is) most pronounced around the waterline where the sunlight penetrates. Weed growth diminishes as the turn of the bilge is reached and the hull surface is shaded by the hull above. When a vessel is hauled, this weed and algae growth is immediately removed by hosing or scraping, which is easily accomplished. Once it dries, it is much more difficult to remove. In tropical waters, bottom fouling could quickly become excessive, particularly if the vessel was not actively sailing for any period of time. Ships were generally careened whenever possible, even if just upon shore, in order to maintain a much faster and maneuverable vessel. 

Thank you once again for clearing the means of applying the viewing distance and for explaining how the copper plates are fastened to the hull and it is in fact the vessels iron bolts acting as the anode in electrolysis and this now makes perfect sense to me as Modern day steel vessels have a similar problem and use zinc bars attached to the hull to act as sacrificial anodes to protect the hull. shafts etc. from electrolysis 

[thibaultron]

The copper/iron problem, as at the beginning of the era of coppering. the ships were built with iron fasteners, and when the copper plates were first used on these ships, the galvanic action did bad things to the original ship's fasteners. I don't remember the complete solution, but they did find ways to prevent this. I think it was a combination of adding a intervening layer of wood to the hull between the ship's bottom and the plating, and using bronze fasteners on new ships.

[DaveBaxt]

50 minutes ago, thibaultron said:

The copper/iron problem, as at the beginning of the era of coppering. the ships were built with iron fasteners, and when the copper plates were first used on these ships, the galvanic action did bad things to the original ship's fasteners. I don't remember the complete solution, but they did find ways to prevent this. I think it was a combination of adding a intervening layer of wood to the hull between the ship's bottom and the plating, and using bronze fasteners on new ships.

Yes Ron  I think I read that somewhere too but they also needed to put something around the bolts too. According to Wikipedia they ended up makeing the bolts out of zinc znd copper allow to what was a great expense. Eventually they did away with copper and instead used Muntz metal 60/40% copper/zinc which I think they mean the plates and not the bolts but could be wrong. I still think there would be issues with the zinc but anyway this was superceded byt anti fouling paint of some discription.