Okay I am sold. Going out to find zinc,copper wire,Epsom salts, sugar and bucket. I am still not sure where to measure current with the power source. I have about 20 battery chargers from phones etc over the years so maybe one will work.
You fellows are way ahead.
I will read the threads for a third time but please be gentle if I ask something which should be obvious.
Merry Christmas to everyone. I have three days in which to attack my CL77.
George
Arizona
For the home plating specialistGeorge, look on the back of the chargers, and try to find one that is 3V 300 milliamps. I actually found two in my pile of chargers. You can check the current at the wire on the zinc, and the wire to the parts being plated.
Davo davomoto
64 CB77 63-7 CB77 Cafe' 67 CL77 64 CL72 66 CL77 big bore flat tracker Many others! Chrome platingA ways back in this thread I talked about a guy that offered instructions on chrome plating. He has them on Ebay again if anyone is interested. $9.95. This thread makes more sense to me having read it. Maybe this info is out on the internet somewhere, too. But here is a place to get it with a small investment.
http://cgi.ebay.com/CHROME-YOUR-METAL-L ... 2c59ab2391 I'll still talk with you guys! Remember m first try was with a HO train power pack and I threw out all those little "I forgot what that DC charger was for" a while back. It was in true home grown forum.."cheap" that it was purchased. You guys can barrow it if nice to me and keep pointing me in the right direction. Merry Xmas!
George, Google Electroplating circuit or similar phrases and you will find more than one site that will show you how to hook up your Digital Multimeter (DMM) to read milliamps. The meter has to be in series with the circuit and not in parallel ((I hope you remember your high school electricity). The charger you use may give its rating in watts. Watts are simply volts x amps. So if have a 5 watt transformer,5 watts/12volts = 0.42 amp or 420 milliamps. That's the max current your charger can take without damaging it. The size and number of parts you put in the bath will determine the current flow so that is why you need a pot to adjust the current to avoid damaging the charger. I think most of this was covered in the thread. I know it is a long thread, but worthwhile reading because we all discovered stuff along the way. I think I put a link in there as well for one of the circuit diagrams on the web. regards and Merry Christmas, Rob More observations plating spokesWell, I managed to get all my spokes and nipples plated while my rims are out for powder coat. It was a long and tedious process and thought I'd share some more plating pointers I learned in the process.
First, I spent some time on the web searching electroplating info. Found a good paper written by a college prof on the subject. A few key points were made in that paper. 1. The ability to plate a metal to a part is based on the ability of the metal solution to "throw", which is the term they use to decribe the actual plating of the metal to the surface of the part. The ability to throw is directly related to the current available which is amps. But there is a sweet spot. More current will throw more plating, but the end result will not be a attractive if done at a lower, more optimum current. 2. Brighterners are required for all zinc plating processes. It appears that most brighteners are proprietary formulas owned by plating supply outfits. From what I read regarding known brighteners, most are pretty nasty stuff and as the bath is used, the brightener needs to be replenished. For commercial platers doing zinc plating, like you see on electrical conduit, the brightener is so effective that no brushing or polishing of the plated surface is required. It comes out of the bath bright silver. So our brightener, which is sugar, is apparently only mildly effective in that we do need to brush the surface to bring out the silver shine. But the upside is it is not toxic or dangerous to use so I'm okay with a little brushing. So, I got thru my nipples and the little washers under them (yes, I know you can toss them, but I thought I'd keep everything that was there) using the set up I've been using all along, which is a 3V, 240 ma charger and a small 1K pot. It took forever to do the nipples and I wanted to be able to do more spokes at once. I dug thru my box of old chargers and found a 12v 800ma charger. With that I was able to do 5 spokes at a time with a bath time of 5 minutes. I was cookin'. The only problem was my puny rheostat could not handle the current. I could smell it cooking and the current readings would drop as the pot got hot. I was constantly fiddling with the pot. I did turn it to zero ohms to see what kind of current I'd get and it would spike to about 1.5 amps. I took the pot out of the circuit and starting plating 5 spokes at a time for 3 minutes at 1.5 amps. The dull gray surface was a little darker, but cleaned up fine with the brush. I kept feeling the charger for any excess heat but it was fine.... for awhile. I got so engrossed in the process, which wsa moving pretty quickly now as I brushed the plated spokes as another batch was being plated, I never checked the charger again. With 6 spokes to go from the rear wheel, the charger died. So, I finished up the remaining 6 with my smaller charger and called it a night. I did put the finished rear spokes on a cookie sheet and baked them at 350 F for 2 hours after plating to reverse any H2 entrainment. I looked a little harder and and found a 12 volt 1000 ma (1 amp) charger from an old modem in my desk. I did not want to cook this one so first thing in the morning, I called a local electronics shop to see if they had a rheostat that would handle the current. I figured that a 25 watt, 1000 ohm pot would work. I started my inquiry with the word "cheap" and the guy had a surplus Ohmite rheostat rated at 100 watts and 2000 ohms. A little big, but for $15 it was perfect. This solved the problem of controlling the current from the bigger charger. So yesterday I did the front spokes with the new set up and it worked like a champ. I was able to do 5 spokes at a time for 5 minutes duration at a current of .85 ams or 850 ma. I put another meter across the + and - terminals of the plating bath to measure the voltage and the voltage pretty much tracked the current. By that I mean for a current reading of 850 milliamps, I got a voltage of .85 volts. This would indicate that the resistance of the plating bath with 5 spokes is about 1 ohm. The night before I found that the spokes hanging from the overhead wire did not like to make contact reliably. So I ended up using clothes pins to clamp each spoke to the wire. Due to the clamping process and the depth of my tank, each spoke would require 4 trips thru the bath because only about 3/4 of the spoke would get plated each time. So, I'd do one end, then flip them and do the other end, then repeat that process for 2 coats of plating on each spoke. Hence the time required to do all the spokes. But, bottom line is they came out great!. Look like new. I Still have to polish them. If you are going to buy a rheostat for your set up, first try to find a charger with some decent current capability. A 1 or 2 amp cheap battery charger would work fine. Then to determine your rheostat rating, I suggest you double the current rating and multiply by the voltage of the charger. So a 2 amp charger would be 4 amps x 12 volts = 48 watts so a 50 watt rheostat should work. Higher is okay, because it just means it has more tolerance for heat. The size of the rheostat should be about 500 ohms. My 2K ohm leaves a little to be desired regarding fine tuning, but I'm happy with it. 1K would have been better and 500K would have been perfect. By the way, you won't find a rheostat that size in Radio Shack. I've already looked. In case I have not mentioned it, Harbor Freight sells a great DMM for 19.99 on sale. With a 20% coupon it is every cheaper. It was measure up to 20 amps, which is a big deal for a DMM. If you do not have a DMM, go get one of theses. You will use it for all kinds of stuff once you have it. As stated above, current is king. I think Wilf mentioned that the bubbles coming off the part are because the process cannot plate quick enough and the current breaks down the bath molecules and produces H2 gas. What you will notice is as you adjust the current up and down, the bubbles increase and decrease proportionally. What I found is a small stead flow of bubbles, and NOT a violent boil around the part, give you the best results in the shortest time. So you need to adjust the current for each different sized part because the surface area of the part determines the current flow because it changes the conductivity thru the bath. Wilf, you said that you did not have good luck plating spokes in the past. I suspect you did not have enough current to do a good job. A final point on plating spokes. Since the issue of H2 embrittlement is of concern, and the papers I've read feel that the acid cleaning/prep process presents more of a risk than the plating process, I did use any phosphoric acid to clean my spokes. I bead blasted any areas that were rusty and dusted each spoke with the blasted for it's entire length. But I did not blast all the old plating off because it is okay to plate over old zinc plate. Each spoke was wire brushed with a steel wire brush prior to going into the bath. With 5 minutes of bath time, you have plenty of time to brush the next batch of spokes in prep for their turn in the bath. I'll polish my spokes later today with a little Mother's and will post a picture or two. Hope you find this helpful. Hey Wilf, if you have boxes of old 305 spokes you are tired of tripping over, I'd be glad to take them off your hands. ;-) regards, Rob
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