I need help with math!!

[Topshot]

Ok so I'm trying to work on this anodizing project. But to determine all the amps I need to use and the time I need to anodize for I have to figure out the square ft of the item I'm working on. And I have no idea how to figure of the square ft of a spool or accuplates. Any of you guys out there good with that kind of stuff

[LTM]

Not that it does much good but square units of anything is an area problem. This is confusing me for the moment also, for how do you figure the area of a circle or a cylinder? For the circle, the area would be the diameter squared (approx, a little over). Hopefully Robert will blink the answers into a post if this isnt too simple for him  

Robert......................,


Good luck Chris,

Leo

[Keta]

Break the part into easier to figure sections and add the results.  The sides of the spool are for your application basically a flat circle, the center is a cylinder, you can use the circumference and width to figure out the sq in.

[Makule]

Unless you need a very precise measure, measure radius of the spool flanges, and do pi x (radius squared) to find the area of a circle.  Multiply that by 4 to get the total inside and outside area of the spools flanges.  Then take the diameter of the center section and multiply by pi, and then multiply by the length to find the surface area of the center portion.  Add that and the area of the sides for the area you are anodizing.

[Tightlines667]

I agree with the previously posted responses but would add..

It may sound stupid but I'd get some graphing paper and lay everything out and trace/draw each object to be plated with measurements so you can break the objects into smaller simpler forms (I.e. rectangle, circle, cylinder, etc).  Then calculate each object's surface area and add them together.

This tool may be helpful

http://www.caswellplating.com/surface.html

Or something similar.

Or consider using a CAD program for more accurate results.

Another helpful tip might be that if you plan on doing objects of the same shape, but different sizes (I.e.  different sized spools, or frames, bases, plates, posts, etc) I think you would find that the objects displacement (put it in a container of water and measure how much it rises), is directly proportional to the volume.  It may also be proportional to surface area given same shape?  O wait..never mind it is not proportional larger objects will have greater volume relative to surface area then smaller ones (I'm a biologist and that's we we can't have super large bugs)...just thinking there may be a way to save yourself some work maybe do 3 different sizes of same shape and plot results on a graph in excell, then you know the curve for that shape and any other sized objects will only need one measurement in order to get your surface area for each object.  Not sure how much that's gonna help?  Maybe use clay to wrap the parts, peel it off (carefully), and cut it to form something like a rectangle or a circle, or something that you can calculate it from more easily.

Hope that helps?

Don't think there are any easy answers here?

[Ron Jones]

Um,
It is only anodizing. You might try a few sizes of bar stock to get a general feel for it and then just wing it. If you are refinishing something, the worst you end up with is where you started.
Ron

[Topshot]

Um,
It is only anodizing. You might try a few sizes of bar stock to get a general feel for it and then just wing it. If you are refinishing something, the worst you end up with is where you started.
Ron

I might be over thinking it. It's actually a lot of science behind it. Trying to figure out how many mills you want to have the part anodized. If you don't have enough your dye won't penetrate enough and your color might not be as "brilliant" as you were hoping. I've been reading through a few anodizing forums and they get pretty darn technical.

[Tightlines667]

Actually I shouldn't have said anything about displacement...It is relatively easy to measure but will only give you total volume of the object...you can not convert volume (in cubic units) to surface area (squared units) unless the object is a simple one of a constant type and a conversion factor is known..such as a sphere..actually it may only work for a sphere since it is the smallest surface area you fan have for a givwn measured displacement/volume. 
So unfortunately it's not gonna work.  You may have the best luck trying to use other methods to closely estimate surface area, and do sum experimenting until you get it right.  Maybe talking to some of the guys who do this stuff regularily might be in order there must be an quick and easy way to figure out what you need. I wonder if you could somehow use a coating of something (weight needed?) or something to quickly figure it out?  For example, if you dip the part in something with a given density, and constant viscosity, (or if it was an even coating from electrolysis), and you knew the amount (weight) used to cover it maybe you could back calculate surface area pretty accurately. 

I think this idea holds promise just not sure about the execution.  You could test this easy by taking something with constant, relatively thin viscosity (like WD-40 or ATF or motor oil, avoid something that has solvents that evaporate) get a stock block of the material your gonna use, like aluminum (the surface needs to be like that of the parts you plan to do to), and weigh the part (or container of liquid) accurately, dip the part, weigh it (or the container of liquid), and if you know the surface area of your object, you can easily come up with a consistent method of X grams of substance to coat = X total surface area of part submerged.  I'd prob test it with a cylinder, and a rectangular cube (w/known surface area) at minimum to see if the relationship holds. 

Like I said I may be over complicating it a bit, you should talk to someone who does this stuff.

[Tightlines667]

Also, although I might be placing the cart before the horse here but, it's worthy to consider that...
if

The thickness of your coating is constant (for which it actually only will be on a flat surface)

Then

'Surface area' will be directly proportional to its 'coating weight'.

So
If you know the 'surface area' of some object, and the 'density' of a liquid of constant viscosity that you dip it in

Then

Total overall average 'thickness' of coating can be calculated
'Measured coating weight' (weight of object after dipping-weight before)/'Surface area' X 'Density' of coating

Since you can assume that this will be about the same on the object of unknown surface area you dip it into*
Then you can easily calculate (aproxamate) the surface area for your part by weighing it, dipping it in your liquid, weighing it again then dubtract to get 'coating weight' and using the following calculation:

Total Surface Area= 'coating weight'/'density' X 'coating thickness'

Density should be know from the liquid you chose, and you should know coating thickness based on your previous test w/an object with a known surface area.  Once you have these two constants, you should be able to easily and quickly measure the Surface area of all parts you need to know at once. 

*Note: It will actually likely be more for open cylinder type shapes, most for closed cylinder shapes, next least for flat surfaces, and least for spheres I think?

Alternatively just play around with different steps of your coating, and by using the same principle above you can weigh your parts before and after coating and calculate the average thickness if the coating you applied given its density...this will let you know how your doing..like if you need stronger solutions, more time or whatever. 

So done else may have a simpler way, but be careful not to use the volume of the parts as a proxy for surface area..they are not proportional!

[Shark Hunter]

When you get it all figured out Chris, I'll send you some parts.