kiddo
Member
CA and BLO
I have this discussion re using CA and BLO as a finish.
My friend is petrochemical engineer at the local refinery. He has PhD in biochemistry and his job is designing with long chain hydrocarbon molecules.
He see one of my nice pens and is intrigued by the CA finish. This starts the discussion as he asks if all pen makers use CA for finish. I say some do but often mix or apply it with BLO or other “secret†ingredients. I ask his opinion on this and he says “let me think about it a whileâ€.
I see him a few days later and this is what he say. (technical mumble-jombo deleted).
CA is like a mass of long, sleeping worms. They flex and slide over one another without getting entangled. This represents CA in its liquid state.
The worms are woken up (catalyzed) by being hit on the head by hydrazine ions stripped from moisture (water) in the environment. Catalyst sprays (like NCF) contain hexaclorofloroethane that has the property of stripping hydrazine ions from H2O.
Anyway, when the “worms†are woken up, they begin to thrash around quite violently. This does two things. Heat is generated by friction from the thrashing molecules, and they start entangling themselves into one massive knot. This is called curing. As the worms thrash around and become more and more entangled, they get so twisted up that they can no longer move and the reaction slows and stops.
In its liquid form, the CA molecules are rather far apart and slide over each other easily. But when it cures into one big molecular knot, they are much closer together. This is what causes an uneven surface or “orange peel†effect as the glue cures and contracts.
Now for the BLO part.
Adding BLO to the mix is like adding dead worms to the mix. They do not dance and thrash around during the cure like the surrounding CA molecules. They do not contribute to strengthening the molecular “knot†of CA molecules. They inhibit, slowdown and weaken the resulting knot. This leads to a softer final cure.
Some mention that BLO is a catalyst. This is not true. BLO contains a small amount of moisture that contributes hydrazine ions to the process, but is not a catalyst itself.
Some say using BLO is a lubricant to spread out the finish more easily and have better control over finished product. In a nutshell, to do this is accepting an inferior (hardness-wise) finish for the convenience of ease and control of application.
These are not my thoughts, but I thought the group may find this discussion interesting. I believe my friend has the knowledge to analyze this correctly and would give me the straight poop.
Submitted for what its worth.
Kiddo
I have this discussion re using CA and BLO as a finish.
My friend is petrochemical engineer at the local refinery. He has PhD in biochemistry and his job is designing with long chain hydrocarbon molecules.
He see one of my nice pens and is intrigued by the CA finish. This starts the discussion as he asks if all pen makers use CA for finish. I say some do but often mix or apply it with BLO or other “secret†ingredients. I ask his opinion on this and he says “let me think about it a whileâ€.
I see him a few days later and this is what he say. (technical mumble-jombo deleted).
CA is like a mass of long, sleeping worms. They flex and slide over one another without getting entangled. This represents CA in its liquid state.
The worms are woken up (catalyzed) by being hit on the head by hydrazine ions stripped from moisture (water) in the environment. Catalyst sprays (like NCF) contain hexaclorofloroethane that has the property of stripping hydrazine ions from H2O.
Anyway, when the “worms†are woken up, they begin to thrash around quite violently. This does two things. Heat is generated by friction from the thrashing molecules, and they start entangling themselves into one massive knot. This is called curing. As the worms thrash around and become more and more entangled, they get so twisted up that they can no longer move and the reaction slows and stops.
In its liquid form, the CA molecules are rather far apart and slide over each other easily. But when it cures into one big molecular knot, they are much closer together. This is what causes an uneven surface or “orange peel†effect as the glue cures and contracts.
Now for the BLO part.
Adding BLO to the mix is like adding dead worms to the mix. They do not dance and thrash around during the cure like the surrounding CA molecules. They do not contribute to strengthening the molecular “knot†of CA molecules. They inhibit, slowdown and weaken the resulting knot. This leads to a softer final cure.
Some mention that BLO is a catalyst. This is not true. BLO contains a small amount of moisture that contributes hydrazine ions to the process, but is not a catalyst itself.
Some say using BLO is a lubricant to spread out the finish more easily and have better control over finished product. In a nutshell, to do this is accepting an inferior (hardness-wise) finish for the convenience of ease and control of application.
These are not my thoughts, but I thought the group may find this discussion interesting. I believe my friend has the knowledge to analyze this correctly and would give me the straight poop.
Submitted for what its worth.
Kiddo