Topic: Carburetor Parts Plating - 65 Autolite 4100

[jwc66k]

I talked with my plater about the bronze/copper finish on the choke housing (seen in the picture), the cover for the vacuum secondaries diaphragm (also seen), the accelerator pump cover and the power valve cover (neither show). I have what appears to be an original power valve cover and it's a shiny copper almost gold zinc finish.
I'm looking for opinions, references and/or comments on the four items listed above as to color and shade.
Jim
Revised to include the two (I found another sample) covers, the secondary vacuum diaphragm and the power valve. The first picture was taken in diffused sunlight, the second in direct. (The black tape is to help the camera focus.)
Jim

[jwc66k]

Added two cover pictures.
Jim

[J_Speegle]

Have seen originals where the body was dyed also. Just6 doesn't seem to hold up as well on the cast body as other places/parts. Thy might not have soaked the body and the lid as long but there is a gold tint to some.

Some pictures (sorry 66 version rather than 65) to help the discussion Some posted earlier  Thanks












Going to have to address some of the same details since I've got one that needs restoring/rebuilding

[jwc66k]

Jeff,
Thanks. A little while ago, I took a choke housing and a power valve cover to my plater to experiment. I included a second power valve cover that has a very distinct gold tint on the inside, as in I believe it's original. The outside is "worn" gold. Naturally, I forgot to take a picture.
Jim

[Bob Gaines]

Jeff,
Thanks. A little while ago, I took a choke housing and a power valve cover to my plater to experiment. I included a second power valve cover that has a very distinct gold tint on the inside, as in I believe it's original. The outside is "worn" gold. Naturally, I forgot to take a picture.
Jim

Just a FYI, i have found in my novice plating attempts that the amount of gold color will in a large part depend on how much zinc content is on the surface. The more zinc the more the gold will stick. Some carb castings seem to lose that zinc on the surface over time and after various rebuild sessions and will not take the gold as well. Sometimes you have to lightly zinc plate the casting to add enough zinc to the surface for the gold to stick to. That is when you have to play with it to get the results you want. 

[jwc66k]

Just a FYI, i have found in my novice plating attempts that the amount of gold color will in a large part depend on how much zinc content is on the surface. The more zinc the more the gold will stick.

The process my plater is going to use involves lightly blasting the old surface then do the plating. Carburetors are cast from an aluminum alloy which required a different process (from iron based part). I'll let him make the decisions. The good part is I got his interest.
Jim

[Bob Gaines]

The process my plater is going to use involves lightly blasting the old surface then do the plating. Carburetors are cast from an aluminum alloy which required a different process (from iron based part). I'll let him make the decisions. The good part is I got his interest.
Jim

  Just giving information for the discussion to try explain why some parts plate light and others dark (besides time in the bath) 

[J_Speegle]

Just a FYI, i have found in my novice plating attempts that the amount of gold color will in a large part depend on how much zinc content is on the surface. The more zinc the more the gold will stick. Some carb castings seem to lose that zinc on the surface over time and after various rebuild sessions and will not take the gold as well. Sometimes you have to lightly zinc plate the casting to add enough zinc to the surface for the gold to stick to. That is when you have to play with it to get the results you want.

Ok from your novice experience do you think how old the batch (used more) is would affect the dye or the amount of dying?

[jwc66k]

Naturally, I forgot to take a picture.

Actually, the pictures are in the first post. I was thinking of a picture of the power valve cover by itself. Here they are again.
Jim

[Bob Gaines]

Ok from your novice experience do you think how old the batch (used more) is would affect the dye or the amount of dying?

I am not sure I understand the question? Can you clarify the "old batch" ?

[jwc66k]

I've tried a couple of "home" plating systems (Eastwood and another from either Amazon or e-bay - it was a long time ago) and they are "cute". That's why I go to the professional. Having operated in a Military and NASA Specification environment, I understand what is acceptable and what is not. QA people get paid to find flaws.
Some of the Mil-Spec plating steps include: several cleaning chemical baths before, mid process and completion; temperature of the plating "bath"; Ph of that "bath"; type of material in the electrode; plating voltage and elapsed time. Once you are set up for Mil-Spec plating, it's just as easy to follow those processes, steps and procedures for every customer. In fact, it may be mandated by the Military to do that to maintain your certification. The cost, when done that way is reasonable. Depending on lot size, it costs between $1.00 and $1.50 per part (screw and nut size).
Jim

[Bob Gaines]

I've tried a couple of "home" plating systems (Eastwood and another from either Amazon or e-bay - it was a long time ago) and they are "cute". That's why I go to the professional. Having operated in a Military and NASA Specification environment, I understand what is acceptable and what is not. QA people get paid to find flaws.
Some of the Mil-Spec plating steps include: several cleaning chemical baths before, mid process and completion; temperature of the plating "bath"; Ph of that "bath"; type of material in the electrode; plating voltage and elapsed time. Once you are set up for Mil-Spec plating, it's just as easy to follow those processes, steps and procedures for every customer. In fact, it may be mandated by the Military to do that to maintain your certification. The cost, when done that way is reasonable. Depending on lot size, it costs between $1.00 and $1.50 per part (screw and nut size).
Jim

In my platting set up I have to use the same procedures and equipment as you list to get a superior end result. Mine is a little more involved then the eastwood type setups .  I started doing it out of necessity because of convenience ,and tired of small parts getting lost. There are so many variables that there is a lot of trail and error. Doing plating isn't for everyone. I end up doing a lot of plating . For the reasons I mentioned it makes sense for me, others maybe not. Although I don't do it professionally the time I have spent doing it trail and error have given me a little insight into various results that can be expected in relation to the things we deal with on the Mustang based cars..

[J_Speegle]

I am not sure I understand the question? Can you clarify the "old batch" ?

In the case of the original supplier do you think (based on what your currently doing) would a tank of chemicals that was used to do thousands or tens of thousands of items lose/reduce its dying ability from use over time. Or another way would the plating IYHO on the first carb look as nice as the last one done before they changed out the tank. Assuming that they ever started fresh and didn't continually keep adding more and more chemicals over time to the same original batch in the tank 

[ruppstang]

Kurt at KP carbs says it does. His best ones are the first in the batch.

[Bob Gaines]

In the case of the original supplier do you think (based on what your currently doing) would a tank of chemicals that was used to do thousands or tens of thousands of items lose/reduce its dying ability from use over time. Or another way would the plating IYHO on the first carb look as nice as the last one done before they changed out the tank. Assuming that they ever started fresh and didn't continually keep adding more and more chemicals over time to the same original batch in the tank

Yes ,to my understanding chemical batch could change over time with changes in PH. The concentration should theoretically stay the same assuming uncontaminated parts. As I understand it theoretically the chemical does not become diluted but the chemical is used up (H2O and chromate) in equal amounts on the part being dipped . New chemical is added in equal proportions.  I know on the smaller quantities for instance when the plating appearance starts to lighten up one possible reason is that the PH has changed in the batch of yellow chromate and you add acid to off set the condition (to high of ph ) to compensate. In a large production process the chemicals are constantly monitored.  The lighter the coating appearance typically means the less corrosion resistance.I am not sure how that thickness is measured. For my purposes my experience with NOS parts gives me a good idea of known range of how it is supposed look when new. I only dip it for the time it takes to achieve that look with no regard for a thickness. I figure if it looks the same level of gold look/color amount  that it should be the same level of corrosion resistance as the Ford specified corrosion resistance.  I am only aware of two ways that the color amount would change . One is by the PH properties and or contamination of the mix and the other by time the part is dipped into batch .   It is easier to diagnose why a part is a certain level of color when it is fresh otherwise you don't know if it is environmental conditions over time after the fact , the chromate solution or the amount of time dipped. The diecast parts like carb bodies take a little creative trail and error and sometimes added steps to get to look right after they have been blasted. Some times some of the parts surfaces are too porous from corrosion or blasting to ever get to look right again.  I cant help but think some of the lighter appearances on the carb parts in the pictures are from environmental conditions over time. I am skeptical that the 4100 main body section was dipped but I could be wrong. If it were purposely dipped the color would be more pronounced . IMHO the light color we see in the picture on the 4100 main body section is from something else other then dipped in the yellow/gold  chromate . The the other smaller parts totally appear to have been dipped. Just my experience. A commercial platting outfit may have different information.