Announcement

Collapse

CASWELD Our new 'Welding' rods

Introducing our latest range of Welding and brazing rods, for the repair of Pot Metal, Aluminum, Stainless and much more.

Please see our web page for details.

http://www.caswellplating.com/restor...ding-rods.html
See more
See less

About to build my first setup, mind giving me a hand on a couple noob issues?

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • About to build my first setup, mind giving me a hand on a couple noob issues?

    Hi everyone!

    Very excited to be here. I've come to fall in love with anodising. I'm building a setup at home and I plan on doing lots and lots of it.
    Planning on making a small business out of it for a niche market.

    I'm spending a considerable amount of money so I'd appreciate some guidance to do it right.

    So here are a couple starter questions

    - I'm about to order build a couple of tanks in polipropilene, around 50L - 60L worth of volume. One thing that I've read all around is that under no circumstance must there be any other metal except the aluminium to be anodised (except titanium and lead anodes). So how are you guys heating your tanks? I've seen a couple of youtube videos where people have resistance heaters. I love this guy's setup, I'm going to mimic it to some extent with digital thermostats. He uses resistance heaters, and if I'm not mistaken they're made out of plain old steel. So how does that work?

    https://www.youtube.com/watch?v=BtYHcsq7s5A

    - Contrary to my belief, I've just been informed that titanium is a bad condutor. I was planning on using titanium wire to hang the pieces, as aluminium will anodise and isolate. So I'm a bit at a loss here on what to use.

    - I've got a couple of unused aquarium circulation pumps. I have air pumps too, but aquarium circulation pumps are much more efficient. Any reason I shouldn't use these? If I do use air pumps, is it ok to use ceramic airstones for better dispersion? What would you suggest I do?

    Think this is it for now.

    Now off to read all the threads as I can!

    Thanks in advance!

  • #2
    Your first set up...sounds exciting!

    Regarding tanks, most use what ever type of plastic they can find in a size that is conducive to their needs and availability. Stainless can be used, even for the electrolyte tank making it the cathode but that's not really practical for a home shop.

    Forget the notion that Ti isn't good for racking/cathodes as the difference in it's use isn't something you or I will notice. A member on the forum (KevinB) can provide more technical info regarding this issue. Besides, it's used in every commercial shop. I use it for both racking and cathodes.

    Heating the tanks can be done with submersible heaters with an adjustable thermostat. I run 1500 watt heaters in all my tanks. Of course you can't use them in the your electrolyte tank but you can use a heating/coiling coil on an external pump.

    As for agitation, air works but is messy, covering everything near the tank with a sticky oily acid film. A pump is better and the best pumps for the application are the kind that can deal with highly corrosive medias. Some guys have had success with salt water aquarium pumps but they eventually give up the ghost and fall apart due to acid exposure. If you want to do it right go with a pump that is meant for the job like a "Little Giant" in a MD/HC series.They are expensive but will be the only one you ever need to buy. You will have to get creative with your flow lines in the tank. It should be based on the shape and size of the parts you intend to run. I have mine on the bottom and two sided acting like a curtain. This was there is no chance of hydrogen build up in any crevices. Do not use those air stones! They dissolve and contaminate the tank.

    Good luck with your endeavor!

    Comment


    • #3
      Originally posted by gardinhackle View Post
      Your first set up...sounds exciting!

      Good luck with your endeavor!
      Thank buddy! I though as much. I work at a copper plating plant, and we use titanium racks bolted onto thick lead strips. Pretty much the same principle and chemistry, except we add copper sulphate to the mix. I'm not a pro or a chemist, so thought best to check here first. Excellent!

      I'm finding it a problem finding submersible heaters that are not aquarium heaters. There are usually capped out at 40 or 45ºC (112ºF). I'm from Europe by the way...
      I see many people complaing their tanks overheat. It's full blown summer here, do I need the heater now or you think I can make do without (ambient 25-35ºC until October)

      I really like this guy's setup on the link I posted above, very nice and very neat. Though I thought two things quite odd...exposed metal in anodising bath, and very very thin plastic tubs yet he has no issue raising it to a boil for sealing. Wow, I'd though those resistance heaters would melt it straight down!

      Thanks for the tip on the right pumps. I dont mind using the ones I have until they break down though. I prefer that to a messy workshop.

      \edit. wow! they are expensive indeed. But nothing beats quality and lasting material.
      Last edited by Pancrecio; 07-18-2016, 11:10 AM.

      Comment


      • #4
        Originally posted by Pancrecio View Post
        Though I thought two things quite odd...exposed metal in anodising bath, and very very thin plastic tubs yet he has no issue raising it to a boil for sealing.
        The metal you see in the tank is a cooling coil likely made of Ti so it can be left in. It might even double up as his cathode. Thin plastic tubs are fine, some polyethylene is good up to 180° F for sealing tanks but most are rated for 140°F which is good for all other tanks.

        You need to find heaters that will achieve at least 120 - 140°F for cleaning and dyes and 180°F for sealing. There's a low temp sealant but what I've heard is it can be problematic. I don't know any large shops locally that like it.

        Comment


        • #5
          We rarely see heaters in the anodize bath. When we do it's because they run Type III (at 32F) and Type II in the same bath and need the heaters when the go from Type III to Type II. Most of our customers will simply run a scrap load at 24-30ASF to heat the tank though. You should be more concerned with cooling the anodize bath. The process can generate a great deal of heat which will raise the temperature of the bath. If left unchecked, you will see your bath temperature reach 80F which make anodizing rather difficult. Much hotter than that and your coating will turn to garbage.

          As for metal in the bath it's quite routine for us to see stainless steel heaters and spargers in the bath. It just needs to be isolated so that no current flow in or out of it. Titanium, stainless and aluminum should be the only metals ever introduced to the bath.

          Certainly as gardinhackle states, avoid fish tank bubblers. Build a manifold using PVC pipe and weight it down or build so you can clamp it down. You mentioned lead too. Avoid it if possible. It's toxic.

          As far as Titanium we also see it used as racking in every shop we are in. It's rare to see it used for cathodes though. The norm we see for cathodes is 6063 Aluminum. Aluminum cathodes get consumed though, and if gardinhackle is using TI cathodes and they work, then they do.
          GL
          kevin
          Last edited by KevinB; 07-19-2016, 08:41 AM.
          Process control doesn't give you good quality, it gives you consistent quality.
          Good quality comes from consistently doing the right things.

          Process control systems for anodizers
          If a post helps you out spread the love and LIKE the post
          _____________________________________________
          Last edited by kevinB: Now. Reason: superfluous typo's

          Comment


          • #6
            Ah right... I studied up the Caswell manual long ago, returning to it now for the actual build. Yes, the ano bath needn't be that high. Didn't have a clue heat buildup would be an issue! Glad to have found this forum.

            I'll be anodising 1 to 2mm 5754 sheets about 40x30cm ( 16"x12" ). I can't find any aftermarket solution so I think I'll have to buy PP plates and build my own rectangular tank. Centering the piece, giving 10cm (4") each side, the tank will have a work volume of around 50-60L. I decided on this design for practical purposes only.

            Doubling the tank volume would help tame heat build up for example. I can do that either X/Y/Z axis. What is would be the optimal anode/cathode distance? I'll be attempting CC not LCD for best colouring results. I could make the tank bigger for optimal results.

            That makes my build simpler then. I can perfectly use aquarium heaters for de-ox/smut/dye, and then one of these to pre-heat the ano tank in the winter before turning on the power supply.



            I can also use these to boil the water in sealing tank. Excellent! (unless I've got something wrong)

            I very much appreciate all your help guys!
            Last edited by Pancrecio; 07-19-2016, 08:24 AM.

            Comment


            • #7
              I know you are in Europe, but I'll throw this link out anyway. Maybe they have distribution over there and would be easier than making tanks.

              LCD is CC anodizing. It's just done at lower current densities than what is normally found in the industry. I believe LCD is done in the 4-6 ASF range whereas the industry norm for Type II is 12ASF. What current densities are you planning to run? Do you have a power supply already, if so what is the voltage and current output capacity of it?

              If the spacing between the part and the cathode is too close you can get an uneven coating. How close really depends on the shape of the part and the size of the cathode. For example if the cathode is a single 1" wide bar, and the part is a 1 foot wide panel, placing the part too close to the cathode can result in a coating that is thicker directly inline with the cathode. The further away the part is from the cathode the less pronounced this will be. Also bath agitation plays a factor in how close the parts can be to the cathode. If your bath is agitated well and your part is a panel it can have the tendency to "rock" in the bath and potentially touch the cathode. If that happens you could have irreparable damage to the part. gardinhackle has more hands on experience than I do so he can probably give you something more definitve, but I would say don't put the part any closer than 8"-10" from either cathode.

              And you are right, the bigger the tank the easier it would be to maintain the temperature. A bigger will also tend to help maintain the chemistry as well. Smaller tanks will build aluminum faster and need to be checked more often. Bigger tank also have a larger cost (not just for the tank, but also chemistry, pumps size, chiller size, etc). They also have bigger environmental concerns as you have more chemistry to dispose of.
              Process control doesn't give you good quality, it gives you consistent quality.
              Good quality comes from consistently doing the right things.

              Process control systems for anodizers
              If a post helps you out spread the love and LIKE the post
              _____________________________________________
              Last edited by kevinB: Now. Reason: superfluous typo's

              Comment


              • #8
                Good advice on the pre-made tanks KevinB! Fabing your own as Pancrecio mentions doing could lead to troubles such as leaking. If you go that route you'd better consider making an outer tank to accommodate for a possible breach.

                ​As for cathode to anode spacing, my parts are typically about 5" away from the cathodes. I have excellent agitation which I found to be very important. If the electrolyte is not kept moving throw out all the parts you will end up with heat build up in isolated spots causing issues like dissolution or hydrogen build up. Temperature control is vital, keeping the temps within the "window" 68 to 72* is best. Some guys will run without worrying about it and adjust time in the tank accordingly. So if the temps end up around 75* at say 45 mins into the run (for the 12 ASF guys) then they might cut it short due to the increased current draw the warmer bath generates. It's risky for a new guy to do though. I run my unit within 2 degrees from start to finish.

                Larger tanks are better at keeping temps within the window and helps reduce dissolved aluminum saturation issues. I may titrate my tank once a year at best but I keep pretty tight controls on the exposure to aluminum. Mind you I don't run my tank nearly as often as I did in the beginning. Having to neutralize an electrolyte tanks and dispose of it can be a p.i.t.a. so you don't want to have to do it too often.

                Comment


                • #9
                  Super info! Thank you so much for this.

                  I was under the impression LCD was CV. Again I stand corrected. To be honest, I haven't sat down to do the actual electrics and math as I have to convert imperial to metric and figure it all out properly. I just know CC is better for consistent color results and that is what I'm aiming for.

                  Still finishing off some vectorial work to precision laser cut the 1mm and 2mm sheets into shapes I'll be working with. What's cool about vector programes is it they can give you exact surface area measurements.

                  I was going to do that last, as I tend to tackle the biggest obstacles first. But right off the bat I do have this available to work with, which is 30v - 5A
                  The absolute maximum I'll be working with for now is the size of an A3 sheet of paper, so 11.7 x 16.5 in = 193,05 sq-inch = 1,34 square-foot
                  But that is overshot, as this will the the absolute maximum functional area. My pieces will be cut from this size into considerably smaller pieces... in fact, let me call my design guy for some real numbers...

                  Model 1 = 0.375 square-foot
                  Model 2 = 0.48 square-foot

                  Yeah, somewhere around these areas. Think this little bugger will do the trick?


                  Last edited by Pancrecio; 07-19-2016, 02:12 PM.

                  Comment


                  • #10
                    11.7 inches X 16.5 inches = 193.05 sqin = 1.34 sqft per side. Unless one side of your part is completely masked, your area is twice what you think or 2.68 sqft. Assuming you are running both sides of the part, the power supply you have shown will anodize that part at 5A/2.68sqft or 1.87 ASF. This will not do very well as the anodize is going to dissolve as fast as it builds. You may get some coating, but my guess is that you won't get enough to dye. The part would probably come out nice and shinny though.

                    For a 5A supply you can have about 1 sqft max to anodize using LCD (I may be off a little because I don't run LCD, but if I am it's not by much). As long as you keep your loads small your power supply should work just fine.
                    kevin
                    Process control doesn't give you good quality, it gives you consistent quality.
                    Good quality comes from consistently doing the right things.

                    Process control systems for anodizers
                    If a post helps you out spread the love and LIKE the post
                    _____________________________________________
                    Last edited by kevinB: Now. Reason: superfluous typo's

                    Comment


                    • #11
                      I dont think I will ever do such a large piece. I'd say I'll top out at 0.5 sqft per side, so 1 sqft total. In reality I'm only interested in dyeing one of the sides, but I guess doing both would produce more consistent and uniforf results?

                      Comment


                      • #12
                        Originally posted by Pancrecio View Post
                        In reality I'm only interested in dyeing one of the sides, but I guess doing both would produce more consistent and uniforf results?
                        No not necessarily. If you don't need anodize on one side of the part, then mask it so it won't be exposed to the acid.
                        Process control doesn't give you good quality, it gives you consistent quality.
                        Good quality comes from consistently doing the right things.

                        Process control systems for anodizers
                        If a post helps you out spread the love and LIKE the post
                        _____________________________________________
                        Last edited by kevinB: Now. Reason: superfluous typo's

                        Comment


                        • #13
                          Interesting... Will work on the math this weekend to prep up, but this may well change my ano tank design yet again. I think I can make do with a much much smaller off-the-shelf storage-box style, less electrolyte volume, and a cathode flat on the bottom. This way I can also hand the sheets on 4 point and basically eliminate rocking from agitation.

                          Follow up question - Why do I need to mask the other side?

                          Comment


                          • #14
                            I have never seen a sole cathode on the bottom before. I've seen tanks with cathodes on the bottom, but they are always connected to the cathodes on the side. I suppose it could work if your part was parallel to it, but if you are running air agitation I pretty sure that it would be a problem. If you know you will always, always, always only anodize one side, then get a tank that is about 10" wide and deep enough and long enough to hold the part standing up. Put cathode material on one tank wall and your part on the opposite side and let 'er rip (you should still mask the back side, although it would not be as critical with this configuration.) I would not lay the cathode on the bottom of the tank. I think that would be a problem just waiting to happen.

                            You would mask the other side so it won't anodize and you could guarantee the surface would/should not be included in the area calculations. Just because the surface is not facing the cathode does not imply it won't anodize. The ions carrying the electrons that get consumed in the anodic conversion are not ejected from the cathode in a straight line like a laser. The ions form more of a cloud that can wrap around and find hidden surfaces to some extent.
                            Last edited by KevinB; 07-22-2016, 02:24 PM.
                            Process control doesn't give you good quality, it gives you consistent quality.
                            Good quality comes from consistently doing the right things.

                            Process control systems for anodizers
                            If a post helps you out spread the love and LIKE the post
                            _____________________________________________
                            Last edited by kevinB: Now. Reason: superfluous typo's

                            Comment


                            • #15
                              Hey guys,

                              So I spent the weekend checking out all the math and the possibilites in hand, for now. Yes, indeed I will only be doing 1 side ano-dyeing. If by any chance there comes a time when I do need to do both sides, then I can just flip the part over, mask the other side, and anodise it I guess. Or even upgrade my tank and PSU. But for now, I'll be rolling with this.

                              For the time being, my biggest biggest piece is, rounded 0.5 sqft. Using the 720, I could theoretically up the current density up to 10ASF to save me 40 minutes, but that would be working at my PSU's near max rating, and I don't think that's a fun idea.

                              I'm aiming at 0.75mils, 6 ASF, that gives me 3 amps and peak 15vdc, which is right around 50% my PSU's rating. I dont really mind the extra 40 minutes bath time, and I guess temperature control will be easier.

                              Almost at a point of making my order at Caswell UK

                              Continuing my noob questions… how does ramp up work? Do I simply dial the current slowly for a minute until the desired 3 amps and the just let it rip?

                              Comment

                              Working...
                              X