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Thanks for the reply. You have good intuition. I was chemist working in pulp and paper field before I was retired. Bleaching paper pulp used lots of redox and optical brightener.
Michel
Michel
@Fish&Chip Ha..ha...who is the biggest chemist: you or Shelk? I never hear that ammonia chloride interchanging words...
Hi Jimsky, LOL.
From memory, I suspect this kind of process :
1- Vinegar : clean the surface, and add CH3COOH on copper surface.
2- Ammonia, NH3, not ammonium NH4+, made a complex with vinegar and copper. Vinegar transform in acetate and ammonia to CuNH4 and made a complex.
3- Salt, NaCL, take place of ammoium in CuNH4. This live CuCl2 + NH3 + CH3COO- Cl+.
Well, maybe I should reopen by chemistry book. May be too Shelk can confirm, or younger chemist in the forum ?
Have a good day,
Michel
From memory, I suspect this kind of process :
1- Vinegar : clean the surface, and add CH3COOH on copper surface.
2- Ammonia, NH3, not ammonium NH4+, made a complex with vinegar and copper. Vinegar transform in acetate and ammonia to CuNH4 and made a complex.
3- Salt, NaCL, take place of ammoium in CuNH4. This live CuCl2 + NH3 + CH3COO- Cl+.
Well, maybe I should reopen by chemistry book. May be too Shelk can confirm, or younger chemist in the forum ?
Have a good day,
Michel
The vinegar definetly helps with oxidation
My problem without combining methods was always, I would either get dark copper without patina, or patina on bright copper
The patina forms just with amonia even without salt, the salt was at least in my mind at the start to create more patterns in the patina
But compared to using sawdust looks to me that using salt creates thicker patina, so it seems that the salt is taking part on the process
My problem without combining methods was always, I would either get dark copper without patina, or patina on bright copper
The patina forms just with amonia even without salt, the salt was at least in my mind at the start to create more patterns in the patina
But compared to using sawdust looks to me that using salt creates thicker patina, so it seems that the salt is taking part on the process
looking real nice....some thing to think about, when I get that far along on my project.
Your work looks great but what I notice is that in the stern the window frames become bigger when we go from the lower gallery up to the middle and top gallery. In the side windows the top and second gallery windows are both the same size?
I can just see this ship stranded on a reef somewhere waiting for the elements to finish her off. Nicely done indeed.
Thank you @Jim J
@Maarten that was really a hard decision to make, all windows are smaller going from bottom to top, both on the back and on the sides, the issue is with the frames, on the back each floor "drops 1 frame", this worked exactly as I wanted on the square windows of the back
But on the sides the shape of the windows on the top floor, with only 1 frame looked weird to me, and ended up deciding that not matching the back would be better, but nice catch and thanks for the input
Today's progress
@Maarten that was really a hard decision to make, all windows are smaller going from bottom to top, both on the back and on the sides, the issue is with the frames, on the back each floor "drops 1 frame", this worked exactly as I wanted on the square windows of the back
But on the sides the shape of the windows on the top floor, with only 1 frame looked weird to me, and ended up deciding that not matching the back would be better, but nice catch and thanks for the input
Today's progress
