Nope. Here's my general process at the moment. Its ridiculously time consuming...
Originally Posted by unterhausen
1. Build bike, cut/face/etc.
2. Hot soapy/dawn detergent wash (get the cutting fluid, etc0
3. Clean towel dry
4. Bake at 400 until it stops smoking to burn off anything on the inside that the wash didn't get
5. Light sandblast (I think the ideal is a 'light' 180 grit profile)
6. Wire hang from the headtube and at this point I try not to touch the frame with bare hands
7. Blow it off with clean/filtered air
8. I wipe on this EW Fast Etch 1 Gallon - Rust Remover Spray - Rust Remover Products - Eastwood with a rag, essentially washing down the frame with it and leaving it damp. Per the phosphoric Acid tech specs, you need to make sure the room is warm. Sometimes I'll let it sit in a lightly warm oven if the shop is cold. I reapply to keep it 'wet' with the etch for about a 30 minutes.
9. Wipe clean with rags and Pre Painting Prep Quart until the rags wipe 'clean'
10. Tape off any areas not to get powder with high temp tape
11. Multiple wipes with acetone using latex gloves. My crazy theory is Nitrile will disintegrate and possibly contaminate the surface
12. Lightly 'torch' the metal with the A/O torch to burn off any little fuzzies from the rag
13. Powdercoat it ( I do not preheat )
14. Bake and hope you didn't screw it up
Walt, who is doing your paint/powder work in SLC, if I might ask?
Powderworks of Utah
They are in West Valley City right off the 2100 freeway. About 10 min. from downtown.
801 973 2321
It is a father/son outfit. If calling on the phone ask for Ray (son) as Walt (father) has some hearing loss and can have trouble hearing you. They have done good work for me so far after some early fumbling around as we learned each other's respective processes/needs.
Be aware that if you go down there in person they will talk your ear off about ANYTHING but especially land speed record cars, BMX, or anything that goes fast. Walt (not me, the PC guy) has forgotten more than most of us here (myself included) have every known about metal fabrication. Great dudes. Tell 'em I sent you.
Originally Posted by rideit
Very cool of you to share. That's a bunch of steps for sure!
Pics of your setup maybe too? Oven?
Why no preheat? Didn't notice a difference or yet another step ?
What is the high temp tape you use ?
Got an email today that my stuff is done. Early! I like so far. I pickup on Monday and will post photos for all to critique...
Originally Posted by einreb
I powdercoated hundreds of complex frames and component parts at a bike manufacturer. Never used an etch or wash.
Originally Posted by Meriwether
Build (weld and braze) frame. Sand blast. Blow off grit. Straight to powder booth.
Used bolts to mask braze on bosses (during blast and coating) and to handle the frame.
Simple clamps/sleeves to mask parts not to be coated. Compressed air to blow power out of the BB threads. Into oven.
Powder gun setup for quick color change--took less than a minute.
Raw frame to ready the assemble in less than an hour.
Never seen an issue with finish durability or frame corrosion, including on my own frames (some of mine were done more than 6 years ago).
Thanks for all the other info and replies up till now. It's been a great learning experience.
So, here's my update:
I got an email last Friday that the frame and 2 forks were done a few days early.
Here's a link to what they look like
Overall I'm happy with the results, but since they're my first powdercoated things I'm pretty easy to satisfy. I got the frame in "Safety Orange" which is just brighter than a flaming pumpkin but awesome. Easy to see any issues with the coveage when using this color. This guy did mostly a good job with coverage in the tight spots and I can't see any orange peel, but there are a few other cosmetic issues. A few pinholes, two on the wishbone crown and one on the lugged fork crown. But I don't know if they are his or my fault. Has this happened to anybody else? Is it possible that any tiny brazing pinholes would create these powdercoat pinholes from the heat escaping from the inside to the outside of the tube through the brazing pinhole?
The other thing I noticed was that on the seat collar's 'window', the edge of the window is thin, can almost see a darker circle there. Same for the underside of the wishbone seatstay cap. Not sure why that happened but it's a subtle difference and maybe the powder didn't coat that area as much before the oven.
He taped off the brake bosses really nicely and didn't get much powder inside the BB or head tube. There is a little powder that needs to be faced but I expected that.
All said, these three items in 3 different colors cost me $100.
I don't know anything about PC, but I know a lot about painting, and there are similarities.
Those were most likely pinholes, and you cannot expect any liquid finish to bridge areas like that unless you mechanically force it to. Many's the time I have found little pinholes like that in the middle of a spray job, and have grabbed a straight pin - something all smart painters have around - to try and get some paint to bridge the gap or lay a drop of paint in it. Get it while things are wet and it will usually flow right in.
With the thin edges, I'll offer a theory. Paint is always thinner the sharper the edge is because the surface tension that keeps the paint in place is far less there than out in the middle of a surface. That's another reason why it's so easy to knock the paint OFF of edges when you try to sand/buff. That's a fact. The theory comes in when you consider that there may be a fine line between gloss and turning the powder so liquid it runs off those edges. Paint works the same way. If you leave your complexly shaped areas a little dry early on, increasing the surface tension, the subsequent paint will stick to that rough surface and not run off it so easily. It might be a factor of too little powder, too much heat, or a combination, but a certain amount of that is unavoidable.
Pinholes like that are usually because of frame flaws, not a flaw in the powder application. Fish eyes are a prep and app issue.
Originally Posted by Meriwether
Common for the powder to be thinner at sharp(ish) edges. The powder liquifies and flows away from the edge. If the pigment is transparent it shows up more.
In a bike production setting reusable silicone caps are put on the brake bosses.
The pinholes......."cratering" develops when air gets trapped in the paint. When drying the air expands and breaks through the surface. Typically, the shop is too hot and humid for the paint to be put on that thick.
For a 100 bucks......not bad. Like the yellow myself.
Great feedback! I think this powdercoater is a keeper. I'll just have to make damn sure I don't have any pinholes in the SS and fork caps. Not sure bondo would help with the oven temps used in PC'ing...?
I do like the coverage and finish to the frame and forks. It's pretty humid here, and he may be running it a bit too hot for frames. The heat is something I can ask about if it happens the next time.
Note to newbs on PC'ing. If your brazing isn't solid, and you have pinholes large or tiny, fill with JB Weld and sand after it dries. I have done a few forks and two frames and wow, the smallest pinholes create larger bubbles/holes in the powdercoat.
The powder guy will cover the pinholes with JB Weld himself for an extra fee of course.
Restarting this to ask a question of those who are knowledgeable. This has been covered other places but not since REEB has been in business I don't think.
A friend I'm building a frame for wants a REEB style clearcoat over steel. My powdercoat guy says he will do it but doesn't recommend it or guarantee the finish when he does a clear over steel without an acid (phosphate) dip first. He says that it will inevitably change colors at the least and degrade or rust at worst over time because without an acid bath you can't get rid of all the oils present on the frame before the powder.
Here's what I found on REEB's site:
"Surface rust is part of our “Black Chrome” clear coating, worts and all is part of the charm of that finish and will not be acknowledged as a defect."
Does anyone have experience with this and know how REEB can do this and have it last? Or DOES it last and for how long? What precautions do you need to take before if you're not doing an acid bath before powder? Acetone wipe, gloves, etc?
This question has been covered numerous times in the past, but the end result is the same...powder encapsulates the substrate but does allow moisture and corrosion to manifest between the layer. The amount of time it takes for this to propogate depends on the care, use, and local climate, but it will happen regardless of surface prep.
I tell my customers that want this finish to enjoy the visually raw fabrication while it lasts and when the spider rust becomes unappealing, send it back and we'll refinish the piece with a coating that protects the frame and looks killer.
Here is an extreme example to reference...
Groovy Cycleworks 330-988-0537: Raw finishes and a seasons worth of racing...
Powdercoating essentials help needed
A great blog post I hadn't seen before. I'm going to send that to me friend, the after effect photos say a ton.
Sorry for bringing this up again. I thought someone may have heard if REEB had a new way of doing it since they call it "black chrome" and not just a clearcoat. Sounds cooler...? :)
Seems like this and other forums tend to repeat the same questions indefinitely since you and the other longer-timers are teaching us noobs (whether that's a good thing or not is up to you, but thanks anyways).
Maybe this thread will become a FAQ of sorts for Powdercoating.
Originally Posted by Meriwether
If you've not been able to dig up the previous info, here is a post I did a number of years ago that gives an inside look into the basic powder coating process.
Groovy Cycleworks 330-988-0537: The Powder process...
Powdercoating essentials help needed
Wow, forget the forums, I'm going to your blog first! That filled lots of the info gaps for me. Thanks again.
Great post Rody, many thanks for sharing.
I talked to my powder guy about a clear-ish finish and he had one other gripe about the finished product, in addition to what's been mentioned. And that was the baking process will discolor the steel in unknown and inconsistent ways.
I've been applying a clear ceramic coating for several years by Cerakote. It's a thin film nano particle coating with superior surface protective properties over any other clear-coat. With proper prep prior to application there will be no future corrosion problems. If the coated surface is breached, let's say by a stone hit on a steel frame, oxidation/ rust would only form where the coating was missing but would not creep under the surrounding coating. And it can be had in sheen's, matte, satin, semi, and high gloss.
would you mind sharing what it costs to ceramic coat a frame? It sounds interesting.
If that's not cool, shoot me a pm please. I wouldn't think it be unreasonable to post at least ballpark numbers.
I think the bottom line is that if you think clear/raw is super cool, you just have to accept that it's going to look horrible in a year or two unless you live in the desert (and even then if you go for a ride an get caught in a storm). I think REEB's statement pretty much acknowledges that but hey, if it sells, some folks won't come back to bug you in 2 years.
If I was going to do the raw thing, I think I'd go for a wax rub or something over powdercoat. Clear powdercoat is just not useful for much in my experience.