Well round three of my plating ordeal worked as expected. I borrowed a 3amp power supply from work and got the same results as my ebay one so that ruled out my power supply as the problem. I even managed to plate my fuel pump as per Jerry's recommendations and it turned out okay but due to the size of it, it was a long drawn out process. This is it at 3amp after 45 minutes and note that there are no bubbles at all as compared to his pic of the "same" pump a month or so ago.
I had to really wire brush and polish it but after the chromate dip it turned out like this.
I still thought something was wrong so I contacted Caswell's tech line and they told me to post on thier forum so I did. This the link to my question and answers.
In the end I had someone PM me the following letter because they didn't want to upset Caswell. Bottom line is that thier manual for the old formula is WAY out of whack!!!
I hope all the links and info that I post in this one "little" post will be quite helpfull to anyone that wants to try home plating with the Caswell kit. As Tim Allen says...."more power"!!!
Now the letter.
"Hi Greg:
(me)It's funny...I had the feeling that we had to be politicaly correct on the forum and that some things had to be held back or risk having a post pulled.
(him)Yep. Caswell will not tolerate harsh criticism, or anything they deem "inappropriate" by their own definition.
I've had 3 of my postings deleted simply because of the detailed information I provided, apparently because Caswell just didn't want people to know it!
(me)Here is a vacuum relay that I plated today.
(him)Wow! That turned out REAL nice! 3 amps sounds too high for 15", but it worked. You should be able to do up to 40-45 " w/ 3 amps, but you'll need more anode.
Anyway, here's the story of how I came to the 80-100 mA/sq-in current:
The plating manuals (old 2002 manual) power requirements for the original formula are way out of whack!
When I first started out w/the kit, I was getting terrible results, and going round and round w/Caswell tech support got me no where. So I went out on the web to try and figure it out for myself.
Found the "Electroplating 101" forum, so joined up and posted my problem there. Got 3 responses that said 25 mA was not enough, use 100 mA/sq-in".
So I did, and it worked!
Ran a bunch of experiments at different current densities, with and w/out brightener, and posted the results:
I got back in touch w/Caswell tech support and showed them. Told them their manual must be wrong. We had 3-4 more correspondences, and they must have contacted the manufacturer, since they sent me this quote:
"I sent this problem to our supplier of the formula we use, and here is what he said:
Voltage has nothing to do with successful plating. The amperes are what count. The parts should have a current density of 15 - 25 amperes per square foot. Your customer states the part is 12 square inches. That is .08 square feet. Multiply that by 20 amperes per square feet and you get 1.6 amperes. He needs somewhere between 0.8 - 2.0 amps( 800 - 2,000 ma), the higher end is better."
So here it was, straight from the horses mouth! Look at the manufacturers numbers and do the math:
"15-25 amperes per square foot" --> comes out to 104 to 174 mA/sq-in !! more than 4 times what the manual says!
Even the manufacturer was inconsistent though, at the end they said:
"12 sq-in ... between 800 - 2,000 ma, the higher end is better." --> that's 67 to 167 mA/sq-in!
Note the low end is precisely what the Caswell power brick was giving me, but it wasn't quite good enough.
That's when I realized that my experimental results were right-on, and the Caswell manual was totally wrong. 50Ma isn't enough, but 75 was fine! So I've been using even higher, as the manufacturer recommends, and it comes out good every time!
I do not understand why Caswell continues to use the wrong numbers though. THEY sent ME the right information straight from the manufacturer! I think that's why they've introduced the "New" formula, w/the correct numbers. Notice that the "New" kit no longer comes with a power brick? It was just to damned difficult to get all the variables just right.
If you need more anodes, you can get pure zinc much cheaper than buying from Caswell.
Zinc etching plates:
They are thicker than Caswells, so harder to cut & bend, but volume-wise, they are only 1/8 the cost, and surface area-wise, only 1/6 the cost. I bought 2 of the 9x12 plates for the same price as 1 of Caswells 8x4 sheets!
You can also get thinner zinc in rolls from Home Depot. It's used as an anti-moss strip under roofing flashing! Very easy to work with, and also a lot cheaper. 2 3/4" wide x 50 ft for $29.
anonymous"
Greg Linton
#45455
I had to really wire brush and polish it but after the chromate dip it turned out like this.
I still thought something was wrong so I contacted Caswell's tech line and they told me to post on thier forum so I did. This the link to my question and answers.
In the end I had someone PM me the following letter because they didn't want to upset Caswell. Bottom line is that thier manual for the old formula is WAY out of whack!!!
I hope all the links and info that I post in this one "little" post will be quite helpfull to anyone that wants to try home plating with the Caswell kit. As Tim Allen says...."more power"!!!
Now the letter.
"Hi Greg:
(me)It's funny...I had the feeling that we had to be politicaly correct on the forum and that some things had to be held back or risk having a post pulled.
(him)Yep. Caswell will not tolerate harsh criticism, or anything they deem "inappropriate" by their own definition.
I've had 3 of my postings deleted simply because of the detailed information I provided, apparently because Caswell just didn't want people to know it!
(me)Here is a vacuum relay that I plated today.
(him)Wow! That turned out REAL nice! 3 amps sounds too high for 15", but it worked. You should be able to do up to 40-45 " w/ 3 amps, but you'll need more anode.
Anyway, here's the story of how I came to the 80-100 mA/sq-in current:
The plating manuals (old 2002 manual) power requirements for the original formula are way out of whack!
When I first started out w/the kit, I was getting terrible results, and going round and round w/Caswell tech support got me no where. So I went out on the web to try and figure it out for myself.
Found the "Electroplating 101" forum, so joined up and posted my problem there. Got 3 responses that said 25 mA was not enough, use 100 mA/sq-in".
So I did, and it worked!
Ran a bunch of experiments at different current densities, with and w/out brightener, and posted the results:
I got back in touch w/Caswell tech support and showed them. Told them their manual must be wrong. We had 3-4 more correspondences, and they must have contacted the manufacturer, since they sent me this quote:
"I sent this problem to our supplier of the formula we use, and here is what he said:
Voltage has nothing to do with successful plating. The amperes are what count. The parts should have a current density of 15 - 25 amperes per square foot. Your customer states the part is 12 square inches. That is .08 square feet. Multiply that by 20 amperes per square feet and you get 1.6 amperes. He needs somewhere between 0.8 - 2.0 amps( 800 - 2,000 ma), the higher end is better."
So here it was, straight from the horses mouth! Look at the manufacturers numbers and do the math:
"15-25 amperes per square foot" --> comes out to 104 to 174 mA/sq-in !! more than 4 times what the manual says!
Even the manufacturer was inconsistent though, at the end they said:
"12 sq-in ... between 800 - 2,000 ma, the higher end is better." --> that's 67 to 167 mA/sq-in!
Note the low end is precisely what the Caswell power brick was giving me, but it wasn't quite good enough.
That's when I realized that my experimental results were right-on, and the Caswell manual was totally wrong. 50Ma isn't enough, but 75 was fine! So I've been using even higher, as the manufacturer recommends, and it comes out good every time!
I do not understand why Caswell continues to use the wrong numbers though. THEY sent ME the right information straight from the manufacturer! I think that's why they've introduced the "New" formula, w/the correct numbers. Notice that the "New" kit no longer comes with a power brick? It was just to damned difficult to get all the variables just right.
If you need more anodes, you can get pure zinc much cheaper than buying from Caswell.
Zinc etching plates:
They are thicker than Caswells, so harder to cut & bend, but volume-wise, they are only 1/8 the cost, and surface area-wise, only 1/6 the cost. I bought 2 of the 9x12 plates for the same price as 1 of Caswells 8x4 sheets!
You can also get thinner zinc in rolls from Home Depot. It's used as an anti-moss strip under roofing flashing! Very easy to work with, and also a lot cheaper. 2 3/4" wide x 50 ft for $29.
anonymous"
Greg Linton
#45455
Comment