Painting and Scheduling

[T^2]

My team considered anodizing/powder coating our offseason bot, and my opinion has been at odds with those of some other members, so I'll add my two cents here.

Generally (and my view is no doubt colored by the fact that I pretty much only do design and fabrication), I abide by the motto that function follows function, and form can go fall in a furrow. I would strongly advise against any cosmetic work on a robot unless it is mechanically excellent. Two days spent on paint means two fewer days for testing and iteration. As for the sponsor argument, I'd wager that my team's sponsors would be a bit happier if we performed well with an ugly robot than if we did poorly with a museum piece.

On the other hand, my boss, who's kind of a sheet-metal nut, liked to say, "If it looks good, it probably works good." If I recall correctly, I replied, "Yes, but does it work well?" To each his own.

[artdutra04]

Originally Posted by DampRobot

Does anyone have any experience or insights into teams anodizing on their own? I've been doing a bit of research, and it appears to be difficult but not prohibitively so for teams to start their own anodizing setup.

I tried it in 2007 on 228. You'll need to spend several hundred dollars buying a high power AC-DC power supply, as well as all the necessary chemicals and dyes. The primary chemical (and nastiest to work with) for the actual anodizing process is sulfuric acid.

It's not a complicated process, but we never really pursued it much after initial tests because we didn't have a high enough power AC-DC power supply, and we did not want to keep such a large volume of sulfuric acid in our build space.

[Cory]

Originally Posted by DampRobot

Does anyone have any experience or insights into teams anodizing on their own? I've been doing a bit of research, and it appears to be difficult but not prohibitively so for teams to start their own anodizing setup.

I wouldn't want to deal with all the environmental regs regarding the usage, storage, and disposal of the acid/etchant. Especially in California.

[James3245]

What are the practical distinctions/trade-offs between anodizing and powder coating in FRC? Are they dependent on each other? Prep required? Turnaround time? Cost?

I'm thinking that we could go back to previous robots and spruce them up a bit for demo purposes/attracting new sponsors but our team has zero experience with adding color to metal parts.

[Chris is me]

Powdercoating doesn't take us particularly long. If it would ever get in the way we don't do it, but we usually find breaks in the team's meeting schedule to get it done.

We have a sponsor who can turn around a decent number of parts in about a week, and we have our own gun / small oven to do smaller parts in house. We've also paid to have particular parts done overnight at a local auto shop.

It's best to really nail design details in your prototype for the best looking result. Iteration often happens but it doesn't mean you can't paint. At the very worst you just replace a painted part with an unpainted part, not the end of the world.

We had our drive base painted over a few days while we were still finalizing what would go on top of it and how we would attach it to the robot. When the drive base was done we just threw everything together all at once instead of going bit by bit. The manipulator was pretty much done in a night and we paid to have it powdercoated during the next school day, ready to install right after school.

Powdercoating or anodizing isn't super essential but if you find a free few days in your schedule it really isn't that hard to fit in. We probably do way to little prep work (we don't account for powder thickness at all in design, probably should) and it's not very hard for us to throw it all together once it gets in. The trick is to find sponsors for slow turn around work and find cheap places to paint for quick turn around.

[IndySam]

We are very lucky here in central Indiana to have a sponsor that will do same day turn around anodizing for us for free. The owner David Hancock hates to see bare aluminum robots

If we drop a part off at Colors Inc. early in the morning we usually can pick it up in the afternoon.

[artdutra04]

Originally Posted by James3245

What are the practical distinctions/trade-offs between anodizing and powder coating in FRC? Are they dependent on each other? Prep required? Turnaround time? Cost?

I'm thinking that we could go back to previous robots and spruce them up a bit for demo purposes/attracting new sponsors but our team has zero experience with adding color to metal parts.

The practical difference is that anodizing impregnates dye into the outer oxide surface of the part while powder coating adds an enamel layer to the outside. Anodizing does not change the dimensions or weight of the part in any noticeable manner. Powder coating adds a few thousandths of enamel, so everything is slightly larger and heavier. Over an entire robot, the powder coating can add noticeable amount of weight.

Anodizing can only be done to aluminum and titanium. Powder coating can be done to anything that can survive up to 500F without melting (the parts are baked in an oven to sure them).

Both processes need the parts cleaned first to get any oils off the part, but all machine marks, scratches, etc. will still be visible in the final anodized part (so you may want to tumble/wire-brush the aluminum part first). Powder coating will hide minor surface blemishes.

[MichaelBick]

Also, ano can be protective if the oxide surface becomes thick enough.