Rack connections?

[kickn]

Okay - first of all HEY! Sorry I haven't been on much but I've been busy setting up the new system and getting things going.

A quick question but first, as promised, some pic's of the new system.

Everything is based on 333L tanks that are filled to about 300L. If you have any questions about its specs please ask - I won't bother listing everything here.

(opps i see you can't post images anymore - ah well)

So...Down to the question. In system2.jpg you see my rack on the tank. I am having problems with corrosion and the leat cable that connects to the rack. I was looking for some stainless steel connectors but can't find anything suitable. I don't want to use nuts/bolts as I want it easy and quick to connect.

I was thinking of putting a plate along the back of the tank so that when you put the rack on the tank - it was connected. Any thoughts?

The thing I worry about is connectivity - but stainless should hold up - what do you think?

[kickn]

Re: Rack connections?

two more images

[acidrain]

Re: Rack connections?

Your racking system looks a lot like mine. The difference is that I used a solid sq. bar instead of box tubing, and threaded the holes to accept a thumb screw.
I drilled two sets of holes per connection... one going vertically, and one horizontally in 1/2in sq. alum. bar. (the horizontal intersects the vertical). Then I tapped the horizontal hole to 1/4in. coarse thread. I used SS short 1/4in eye bolts for the thumb screws (easily gripped even with gloves). I mostly use 8ga alum wire for hanging the parts, and when bent in a U shape, are lowered into the vertical hole, then clamped with the thumb screw.
The bus bars are connected with alum screws to alum wire, where the PS leads are connected far away from the acid fumes.
This works pretty well... I have had to disassemble and clean them once in the last 9 mos. of anodizing. I have purchaced solid SS bar, and will build my next rack out of that.

[kickn]

Re: Rack connections?

My current problem is connecting the rack to the PSU on that side. I don't like keeping copper so close to the bath and with the fumes it quickly breaks down.

I was thinking of putting a plate on the back of the tank and just sitting it on there but I'm not sure how much of a connection that would make.

I'm using s/s so my hope is that it would hold up to this. I would then use some s/s bolts to fix this and fasten the copper wire underneat the lip of the tank.

what do you think?

[acidrain]

Re: Rack connections?

Well, just sitting the bar on a powered bar won't work... you'll have to connect it with a SS or aluminum screw to the bar, but you are on the right track.

[sswee]

Re: Rack connections?

I have a similar setup, only using aluminum bar. I have a SS bolt threaded through the bar and sticking out the other side long enough to put the power lead on with a SS wingnut. The power lead has an aluminum eyelet soldered on and shrink tubed so there is no copper exposed to worry with. No problems yet. I have had to get SS parts from a bolt supplier or a marine supplier. SS

[M_D]

Re: Rack connections?

One option would be some Ti bolts, nuts, and angle for your rack(s) (with pre cut holes every 1") from Servi Sure. The angle was about $1.05 per foot last time we bought it.

http://www.servisure.com/home.html

[kickn]

Re: Rack connections?

Its not the racking that is the problem - is connecting the rack to the power. I know I can bolt on some wire but i was looking for a more friendly solution.

Thats why I thought a busbar along the back/top of the tank would let me sit the current rack on it and it would auto-connect. If its s/s then there should be lots of connuctivity/etc.

?

[M_D]

Re: Rack connections?

I knew it wasn't the rack per se, but I guess my point was the Ti wouldn?t corrode like the stainless and other metals will and might solve some of your problems. I have had some 303 stainless around the electrolyte, and it soon corrodes, other alloys such as 304 might be better but still not like Ti. We just connect the power supply wires (which have a soldered brass eye terminal on the end) to a 1/4" Ti stud. Every once in a while we clean them or replace them.

We machined a large copper bus bar for a commercial anodizer a few years ago, but I don't know exactly how it was used.

I know heavy parts are sometimes just hung on anodizing racks and the weight keeps the connection good enough (although for the submerged connection directly to the part I'm sure that they can't be disturbed during the process). So maybe if your rack is heavy enough, and any excess corrosion is kept cleaned off, a bus bar that the rack sat on may be good enough.

Perhaps you could attach your power supply wire(s) to a small C-clamp or vise grip to make quick work of attaching them. I know corrosion would still be a potential problem, but if the connection were kept away from the acid enough it should be minimal. We are going to revise and up grade our entire anodizing line soon, and will probably machine some custom quick connect electrical plugs out of Ti.