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TINKERGINEERING
I accidentally powder-coated some parts that needed to be zinc plated, namely the shock tower attachment hardware and the rear bearing cover, and I reached out to Caswell about their kit, but, I was also thinking of just getting their Yellow Chromate and attempting a zinc plating in my garage. I saw some videos on it and their parts turned out pretty good for what they are needed for, so I wanted to ask if any of you have zinc-plated these in their garage. What did you do? Would you do this again?

I have sandblasted all the powder coating off and I kinda want to try this process out.

Seeking the 914World Belssing to mess up my car. Just kidding someone has already removed the gas engine anyways. I think I can do this.

These are a few of the parts that I know need Zinc. What other parts need the Yellowing? My black and white manual isn't telling me...

Frances
and Dad
worn
Sure. Just did the calipers for the 4 cylinder rustoration car.used solutions that are several years old and they still work. I power the plating with a battery charger, usually set on six volts. A trick that I use is to hook the charger up to a lighting dimmer so I can control the rate. I simply wired the dimmer and a plug into an electrical box. If this doesn’t sound crystal clear to you then get a qualified electrician or similar to help. Really though plating is more fun than upholstery.
worn
QUOTE(worn @ Mar 16 2024, 06:05 PM) *

Sure. Just did the calipers for the 4 cylinder rustoration car.used solutions that are several years old and they still work. I power the plating with a battery charger, usually set on six volts. A trick that I use is to hook the charger up to a lighting dimmer so I can control the rate. I simply wired the dimmer and a plug into an electrical box. If this doesn’t sound crystal clear to you then get a qualified electrician or similar to help. Really though plating is more fun than upholstery.

I want to add that I have been using Caswell solutions but have branched out for zinc electrodes. You cannot plate over rust, so a sandblaster is helpful. Also, acid treatment such as phosphoric acid makes a good surface for the zinc.
mepstein
Frances and Dad -

Yes you can do it. It has a bit of a learning curve. It’s nice to be able to do things as you need them.

Downside is storing the chemicals between using them.

Another option is to hit the easy button and send them to PMB. They do a great job. They are finishing some parts for me right now.

Mark
TINKERGINEERING
Awesome! Thanks for the input I appreciate it! I think I'm going to give it a shot.
mgp4591
QUOTE(TINKERGINEERING @ Mar 16 2024, 08:30 PM) *

Awesome! Thanks for the input I appreciate it! I think I'm going to give it a shot.

Frances, the chemicals are kinda nasty for the small amount of parts you have to plate. I'd agree with Mark and send them to us at PMB...we still have your stickers on our equipment! I'd love to plate up some purty gold pieces for you!
Superhawk996
Be careful with the acids. Wear PPE. Read and follow Caswell instructions meticulously and you’ll be fine.

The yellow chromate is fickle. Hang to dry with heat helps and don’t handle for 24 hours. Works 95% of the time. Every now and then I get a part that the chromate brushes off and has to be redone from scratch. Haven’t figured out what causes the seemingly random failures.

mgp4591
QUOTE(Superhawk996 @ Mar 16 2024, 08:52 PM) *

Be careful with the acids. Wear PPE. Read and follow Caswell instructions meticulously and you’ll be fine.

The yellow chromate is fickle. Hang to dry with heat helps and don’t handle for 24 hours. Works 95% of the time. Every now and then I get a part that the chromate brushes off and has to be redone from scratch. Haven’t figured out what causes the seemingly random failures.

After dipping in the chromate, pressurized air is necessary to dry the chromate and give it its color and iridescence. Then the oven at around 120 for about 10 minutes oughta do it.
RRietman
QUOTE(TINKERGINEERING @ Mar 16 2024, 06:58 PM) *

I accidentally powder-coated some parts that needed to be zinc plated, namely the shock tower attachment hardware and the rear bearing cover, and I reached out to Caswell about their kit, but, I was also thinking of just getting their Yellow Chromate and attempting a zinc plating in my garage. I saw some videos on it and their parts turned out pretty good for what they are needed for, so I wanted to ask if any of you have zinc-plated these in their garage. What did you do? Would you do this again?

I have sandblasted all the powder coating off and I kinda want to try this process out.

Seeking the 914World Belssing to mess up my car. Just kidding someone has already removed the gas engine anyways. I think I can do this.

These are a few of the parts that I know need Zinc. What other parts need the Yellowing? My black and white manual isn't telling me...

Frances
and Dad

been doing tin zinc plating at home for years mostly on japanese motorcycle stuff. kind of fun, but takes time. the solution is white vinegar/epson salt/ cane sugar. need a low volt supply---4-6v@300-500 ma. lot of guys use old phone chargers. I have an actual electroplating supply. my previous one I got from a buddy who had a dental lab (they don't use them anymore). you need to get the parts very clean. sand blasting is best, then treat them as if you were going paint them. your fingers are dirty! wear gloves.
good luck
Randy
Superhawk996
QUOTE(mgp4591 @ Mar 17 2024, 12:20 AM) *

QUOTE(Superhawk996 @ Mar 16 2024, 08:52 PM) *

Be careful with the acids. Wear PPE. Read and follow Caswell instructions meticulously and you’ll be fine.

The yellow chromate is fickle. Hang to dry with heat helps and don’t handle for 24 hours. Works 95% of the time. Every now and then I get a part that the chromate brushes off and has to be redone from scratch. Haven’t figured out what causes the seemingly random failures.

After dipping in the chromate, pressurized air is necessary to dry the chromate and give it its color and iridescence. Then the oven at around 120 for about 10 minutes oughta do it.

Thank you for the tip! Will try this next time.
mb911
I appreciate the effort here but for $140 you can get this all done. Almost not worth messing with all the chemicals Click to view attachment
technicalninja
agree.gif agree.gif agree.gif agree.gif

That's a BUNCH of stuff for 140!

I too was looking at the Caswell kits.

They've got a black zinc process I want to try on carb bodies.

For the normal cad stuff, the MB911 route looks best to me.

Looks like two weeks' worth of small tank plating for chump change to me.

No nasty chemicals, no smells, no screw ups and "have to do it again".
mepstein
Buying the kit does give you the opportunity to make a video
I do all my own prep and then send it out. Luckily have a friend willing to take it to a shop that does bulk plating. Small batches go to PMB. There’s really few choices on the east coast, just like chrome plating.

When you send it in bulk, you aren’t guaranteed to get everything back. I’ve been lucky so far and if stuff is missing, it wasn’t a big deal. If I had really important parts, I’d want a place that documented the parts before and after. 914 parts are a dime a dozen but there are always small parts on special items that are almost irreplaceable. Doing it at home is a good solution if you are worried about loosing something.
Shivers
QUOTE(mb911 @ Mar 17 2024, 02:45 AM) *

I appreciate the effort here but for $140 you can get this all done. Almost not worth messing with all the chemicals Click to view attachment


You have a very good friend smile.gif
technicalninja
QUOTE(mepstein @ Mar 17 2024, 08:23 AM) *

Buying the kit does give you the opportunity to make a video
I do all my own prep and then send it out. Luckily have a friend willing to take it to a shop that does bulk plating. Small batches go to PMB. There’s really few choices on the east coast, just like chrome plating.

When you send it in bulk, you aren’t guaranteed to get everything back. I’ve been lucky so far and if stuff is missing, it wasn’t a big deal. If I had really important parts, I’d want a place that documented the parts before and after. 914 parts are a dime a dozen but there are always small parts on special items that are almost irreplaceable. Doing it at home is a good solution if you are worried about loosing something.


He's SOOO right!

When I send a block or a head to the machine shop I completely strip EVERYTHING off of the item and ONLY send exactly what they need to do the job.
I also include a "parts list" of what I sent...
Been down the primrose path of missing tiny parts way to often myself.
mb911
QUOTE(Shivers @ Mar 17 2024, 05:34 AM) *

QUOTE(mb911 @ Mar 17 2024, 02:45 AM) *

I appreciate the effort here but for $140 you can get this all done. Almost not worth messing with all the chemicals Click to view attachment


You have a very good friend smile.gif


Nope just a local business. They kind of make the price up each time. It ranges from $60-$180 depending on how they feel. This bucket got shipped out to a very good friend on Friday. Truth is it’s a crap shoot as to what you get back. If anyone is willing to gamble I can offer to drop them off at the plater for you but you have to have it prepped and make it easy for me to drop off the parts and pick up that’s all
technicalninja
Another tip...

If you want bright shiny cad the part needs to be shiny BEFORE the cad is done.

You bead blast the part and plate over a rough surface it will plate "flat" instead of gloss.

Vapor honing might be better, I haven't seen vapor honed re-plated stuff yet.

Most of the re-plated stuff that came out nice had to go into something like a rock tumbler first.

Polish then plate seems to produce the nicest finish in my book.
StarBear
Advantage of home playing is one can do just 2-3 parts at a time. I think mine were done for 10 sec dip at first but 20 sec dip had more shine and bling. Next time I prepped and sent a small bucket full out. Had to prep but turned our really well. Agree - photo document all pieces and include list with parts and pics when sending out.

I think the PET list indicates which ones are plated. Include front/rear latches and engine lid screws. Have seen some door hinge screws plated but they came painted body color. My under dash screws are plated, too.
TINKERGINEERING
Love this
Okay for best case scenario and best looking outcome- call Eric @PMB
For making videos and showing learning lessons try this at home.
Full safety gear

30 seconds in the yellow chromate
High pressure air dry
Bake 100 degrees
I’ll read more

Yea I need to get this thing done. Might skip this part and call PMB.
sixnotfour
You are very ambitious..PMB money well spent... call it a day Off for fun..
mepstein
QUOTE(technicalninja @ Mar 17 2024, 09:54 AM) *

Another tip...

If you want bright shiny cad the part needs to be shiny BEFORE the cad is done.

You bead blast the part and plate over a rough surface it will plate "flat" instead of gloss.

Vapor honing might be better, I haven't seen vapor honed re-plated stuff yet.

Most of the re-plated stuff that came out nice had to go into something like a rock tumbler first.

Polish then plate seems to produce the nicest finish in my book.

I’ve vapor honed the parts before plating. It does a nice job but the problem is flash rust. I’m talking minutes or less. You have to clean off the water and glass and wd40 right away. I mostly bead blast and then wire wheel the parts I want pretty. Polishing further would make even shinier but I’m not interested in the effort for the return. Like everything, prep is 95%.

Yes, Ben takes care of me more than I deserve. I just caution people about sending out a car full of parts to plate. If the parts get lost in the mail, it’s really a bummer. To help combat this, I now put two shipping labels on big boxes. I lost an entire transmission and I think it was due to a missing label. The other issue I had is, some of the plated parts held the plating solution. I think it was a couple of fuel rails. They spilled out during return and ruined a big portion of the plated parts. It all got redone. Blasted off the plating, wire wheel and shipped out, redone, shipped back. My fault, my dime. Get the parts racked if they hold solution. Costs more but has to be done. That’s why some of my parts go to PMB.

That 70 lb bin of parts probably took me 40-50 hours of blasting, wire wheel and cleaning. Some of the suspension pieces take an incredible amount of time to remove the undercoating that was sprayed over them. Blasting won’t usually remove it. Brake clean and an old flat blade screwdriver and a wire wheel is needed. Small bolts and threaded hardware get held against a bench grinder fitted with a wire wheel. At the very least, wear eye protection. Eventually, the wheel will grab one and send it flying. The wire also lets loose from the wheel. I wear safety glasses, respirator and a throw away full face shield. Way cheaper and easier than a trip to the ER to remove a sliver of metal from my eye.
mgp4591
QUOTE(TINKERGINEERING @ Mar 17 2024, 08:59 AM) *

Love this
Okay for best case scenario and best looking outcome- call Eric @PMB
For making videos and showing learning lessons try this at home.
Full safety gear

30 seconds in the yellow chromate
High pressure air dry
Bake 100 degrees
I’ll read more

Yea I need to get this thing done. Might skip this part and call PMB.

If you want the brightest yellow zinc, I'd glass bead your parts after the sandblasting. And I don't know what solution others are using for dichromate, but I only dip for 15 - 20 seconds then a dip rinse before the air pressure drying. And you want to be methodical about the pressure drying or you can have uneven color and runs in the finish. Talk to Eric, send them to us, and I'll make those parts SHINE for you, girl!
technicalninja
QUOTE(mepstein @ Mar 17 2024, 01:02 PM) *

That 70 lb bin of parts probably took me 40-50 hours of blasting, wire wheel and cleaning. Some of the suspension pieces take an incredible amount of time to remove the undercoating that was sprayed over them. Blasting won’t usually remove it. Brake clean and an old flat blade screwdriver and a wire wheel is needed. Small bolts and threaded hardware get held against a bench grinder fitted with a wire wheel. At the very least, wear eye protection. Eventually, the wheel will grab one and send it flying. The wire also lets loose from the wheel. I wear safety glasses, respirator and a throw away full face shield. Way cheaper and easier than a trip to the ER to remove a sliver of metal from my eye.


THIS IS THE WAY!
The attention to detail spoken of in the above post is what the difference between a "wannabe" and a restorer is.
50 hours...
Massive prep followed by high quality finishing is the only way to go in my book.

Buying NOS is often a much, much quicker way it just goes through money with equal rapidity.

Now, the red area I have PERSONEL experience with...
I once caught one of those red microscopic embers that a grinding wheel puts off in the dead center of my left eye. It melted the lens a tiny bit and went under the surface. Two days later it was hurting, my eye felt like I'd gotten a tiny bit of B12 in it, stung a bit. I went down to my local ophthalmologist, and he first tried to pick it out with a metal pick! blink.gif
When that didn't work, he brought out a contraption that looked like something from the movie Saw.
It was a "head vise" with many adjustable pads.
After locking my head in this he asked, "Do you want the back straps on?"
Hell NO!
He then attaches another apparatus to it and this puppy is a horizontal drill press, a little, tiny one!
He pulls out an "optical drill bit" Looked pretty normal!
He chucks it up, gets under magnification, starts it spinning, and says "Don't blink, it will tear your eyelids OFF!" yikes.gif yikes.gif
It took 2 seconds.
Didn't hurt AT ALL!
Worked perfectly!

Watching a drill bit enter my own eye and NOT blink is one of the hardest things I've ever done!
Never again!
Eye protection should be mandatory at all times in the shop, not just when you're making sparks...
burton73
You can see U Tube videos on how to do this the easy way and you can use simple d cells for the battery but after doing this you still end up with chemicals to dispose of and the acid is nasty. I know that you went on the PMB tour and where in the chemical room (they are set up for this) well just easer to send to them if they will do it. They have the mix down and give you a great golden finish if that is what you want.



Good luck

Best Bob B



TINKERGINEERING
Jeez Today was drill press rough grind and then small dremel erasing the rubber under coat. Now its soaking in the paint remover in a zip lock bag. Then back intiothe sand balsting. Yea after hearing your thoughts, PMB. I need to also get the two piece strut tower bushing support. Elephant I think. PMB has them listed. I pressed out the originals.
I like being able to do things on my own. Sometimes faster but we are moving and need to keep things going forward. And after all your thoughts it will be better in the end.
Van B
I chose to buy the kit, but that was more because I don’t have anyone local at a reasonable price. That said, once I had everything, I’m glad I got it. I’m only refinishing NLA or expensive parts that are otherwise in good shape. I also, got the .8mm HVLP touch up gun from harbor freight that is perfect for cerakote.
VaccaRabite
QUOTE(TINKERGINEERING @ Mar 17 2024, 11:23 PM) *

Jeez Today was drill press rough grind and then small dremel erasing the rubber under coat. Now its soaking in the paint remover in a zip lock bag. Then back intiothe sand balsting. Yea after hearing your thoughts, PMB. I need to also get the two piece strut tower bushing support. Elephant I think. PMB has them listed. I pressed out the originals.
I like being able to do things on my own. Sometimes faster but we are moving and need to keep things going forward. And after all your thoughts it will be better in the end.


This is the way! Eric and Larry and the crew at PMB will take care of you!

I have not seen your videos in a while, but the ones that I have seen you (and hopefully) your dad have been wearing eye protection. I didn't when I was younger and have gotten lucky on several occasions. The biggest was the inch long strand of wire wheel that got thrown into my forehead and stuck there like a dart!

Mark is also on point about wearing a respirator when grinding. I bet most of us don't, even though we KNOW all the crap we are throwing into the air is not good for us to breathe. I use one when I know I'll be grinding a while, and I should use it even for short sessions but I don't. And that's dumb.

Zach
Detroit
Sixty bucks at a local plater. I doubt you can buy all the required materials for that. Never mind actually doing it, and then storing the stuff after. Unless you've got a little business where you're plating things on a regular basis, to me doing it yourself just doesn't make sense.
Granted, I live in Detroit. It's likely easier to find places that do this type of work here than elsewhere.

Click to view attachment
friethmiller
I think it's up to you on how to proceed. On my last restoration, I decided to do my own plating. I think on my current LE build, I'll do the same. It's just my choice. I like to take on the things I think I can do. Plating was something new for me, and I enjoyed the process 100%. I did zinc and zinc-nickel plating. The later is a harder finish but it doesn't really take the chromate. I personally like the zinc + blue chromate. My last image has the door plates that I plated with this coating. My only advice that hasn't already been given is plan out how you will dry these plated pieces. The chromate is extremely soft and can easily be rubbed off. Also, careful with blasting the part with air, it might blow off the chromate. Might need to wait a bit. I'd run a trial on some scrap metal to get a hang of your process. Good luck!

Note: see how [in my last image] one of my pedal cluster springs has rust inside. Plating doesn't stick to it at all. It all has to be clean, clean, clean. smile.gif
mepstein
Not to belabor the point but once I finished blasting and wire wheeling, I was really happy not to have to touch it again.
Karl R
I used the Caswell kit for a 928 I built. I couple of things:
1) my parts did not always come out consistent. Sometimes I got a nice shiny finish and somethings I got more of a galvanized finish. Sometimes there were shadows with no plating. I'm sure these issues could be improved with experience and patience, but know that it is not like spray paint or something where it mostly just works.
2) Its been a few years. The extra chemicals are in my shop probably going bad and eating through their containers. I don't love that. Also the parts did not really hold up to Honolulu conditions and are discolored and/or rusting. The zinc + 'copy cad' does not have the durability of a real cad finish.
mepstein
We have a place near us that will do cad. They told me ~$100lb and it has to be spotlessly clean before they touch it. Obviously I’d have to be picky about what I plate. The two pictures above are 70lbs of parts.
technicalninja
QUOTE(mepstein @ Mar 19 2024, 05:56 PM) *

We have a place near us that will do cad. They told me ~$100lb and it has to be spotlessly clean before they touch it. Obviously I’d have to be picky about what I plate. The two pictures above are 70lbs of parts.


100/lb
70lb
$7000!!!!!!!

You ARE dedicated Sir!
mepstein
QUOTE(technicalninja @ Mar 19 2024, 07:29 PM) *

QUOTE(mepstein @ Mar 19 2024, 05:56 PM) *

We have a place near us that will do cad. They told me ~$100lb and it has to be spotlessly clean before they touch it. Obviously I’d have to be picky about what I plate. The two pictures above are 70lbs of parts.


100/lb
70lb
$7000!!!!!!!

You ARE dedicated Sir!


No, this is zinc. It was a couple hundred all in and lots of time in front of the blast cabinet.
FourBlades
I have the Caswell kit and do a lot of yellow chromate finishes.

It is not easy to get a good finish until you practice a lot.

One word of warning: the chromic acid used for yellow zinc is a strong acid and is very toxic as well. It is super nasty. It will eat through metal over time. I keep it in glass containers only. If you leave the cover off it overnight, it will corrode all the metal within 3 feet of the container.

Caswell has a few tips that I found make a big difference.

First you need to dip your parts in a 3% HCL solution for 5 seconds then rinse with fresh water BEFORE zinc plating.

Second, you need to plate for 25 minutes with the right amperage level to get a thick plate on the part. Thin plate will result in the yellow coating coming right off.

Third, after plating you need to dip in 3% HCL again for 5 seconds then rinse with fresh water BEFORE dipping it in the chromate solution. How long you chromate depends on how strong and fresh your chromic acid solution is. You can always dip it longer if you pull it out and it is not good enough as long as it is still wet with the chromic solution.

I have the best results from hanging the parts up to dry overnight.

Like most hobby platers I do it for convenience of I need this part done now in my restoration and I don't want to risk having it lost. It is probably more expensive to do a couple cars worth of plating yourself than sending it out.

Good luck.

John

Click to view attachment
TonyA
Are those pieces that go under the ball joint supposed to be Cad plated?
mepstein
QUOTE(TonyA @ Mar 20 2024, 06:41 PM) *

Are those pieces that go under the ball joint supposed to be Cad plated?

The washers with all the little fingers? Yes.
Mikey914
Francis,
The hard part is the cleaning. There is something very satisfying about doing it yourself.
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