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Posted: 5/31/2015 5:07:05 PM EDT
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Well I have made my first attempt at anodizing a couple of 80% lowers I did at home.
Results somewhat good and somewhat bad.....I see why the anodizers charge what they do. These two lowers were done at the same time...one had just the tumbled finish by the manufacturer and the billet Quentin Defense had a light abrasive blast. The billet came out noticeably lighter than the forged one. Both had some splotching on them...not sure whether it was poor cleaning or the RIT dye I used.....or the power supply ( battery charger said it had a manual mode but appeared to be automatic ). The amps started out at around 8 and gradually went down to about 4, then after an hour or so dropped to about 2 amps. (Both receivers in the acid bath at same time). I will get myself a proper power supply and probably try them again....and buy some dye from Caswell plating. They don't look too bad from a distance lol...Battlefield Pick ups I've seen are worse.  </a>" />
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Not sure what caused the line of splotches across the one in the bottom picture. |
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Heck I'd be happy if that was my first attempt.... If your using for a retro build, it's perfect anyway.  No kit....just distilled water 3 gallons,1 gallon battery acid,four-five tablespoons of 100% lye,RIT liquid dye...and a car battery charger. The forged one just had the tumbled finish from manuf.The billet media blasted softly w/aluminum oxide. The tumbled finished one came out shiny black and smooth,the blasted one a little lighter in color with a slight purple hue to it. I'm going to try again in a couple of weeks after I get a better power supply and maybe some dye from Caswell Plating. You can find info here...http://www.thefintels.com/aer/homealuminumanodizing.htm That's the guide I used for this attempt. Keeping the acid solution at 65-75 degrees was challenging in a garage with temps in the high 80's...had to add some ice around the bucket to cool the acid solution down. Probably wouldn't be too hard if I lived up north somewhere...but here in Texas it's warm and muggy. |
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Looks splotchy but keep it up OP Yeah they are both kinda splotchy....don't know whether it was the dye or just didn't get them clean enough. Could have been the current...I'm not sure.Like a whole lot of little specs.. I'm going to try it again when I get a better power supply and some good dye. Surface prep appears to be every thing and I didn't spend much time on them. I can always cover them with Norrell's later if I can't get them to look right. I'm not a machinist but bought a Harbor Freight mini mill and milled the pockets on them....trying to anodize them myself is just another item on the bucket list. 60 yrs old and running out of time LOL. And yes most of what I'm building are retro's. |
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Did you use an anodizing kit And where did you get the products? How did you prep the lowers? No kit sir....just battery acid and RIT dye and battery charger. Info here....http://www.thefintels.com/aer/homealuminumanodizing.htm Washed in detergent,rinsed w/distilled water, etched w/ distilled water and lye,anodized in 3 gal. distilled water w/ 1 gal. battery acid, dyed at 100 degrees for 30 minutes and then sealed in boiling distilled water for 30 min. |
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In for comments as I have 3-4 ready for anodizing. Probably another 5 that will be at some point. Plus some buddy's. I assume its all in the prep. Bead blasting or tumbling perhaps.
OP, for what its worth, even with as hard as it is to see the details in the pics, they look more than good enough to keep. However I understand not being happy with your first attempt. Keep us updated!!!!! |
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Uggg. Those dam spots. I too have a problem with the spots showing up. They seem to be worse on 6061 but they can show up on 7075 too. Caswell trouble shooting says they can be caused by the following: Oil on the part, Uneven wetting of the parts when dying impurities, Local overheating by polishing, Gas bubbles on anodize pores. I just did two lowers this weekend both with extensive prep and I still had spots on one of the lowers. The only thing I did differently between the two was agitate the dye. I did this by grabbing the lower and swishing it around every two minutes.
My Line up: Bead Blast lowes Hand wash 200 degree caswell degreaser 5min full rinse Lye Etch 2min Full Rinse 110 degree Caswell De-Ox de-Smut 3 min Full Rinse Anodise 2.5 amps for 90 min agitate with fish tank pump Neutralize in baking soda and water Full rinse Dye 30 min at room temp agitate every 2 min Full rinse Seal in boiling water for 5 min. This is my second attempt and I am much happier this time. The first time I did not do enough prep. I will try and post some pictures tonight when I get home. |
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Uggg. Those dam spots. I too have a problem with the spots showing up. They seem to be worse on 6061 but they can show up on 7075 too. Caswell trouble shooting says they can be caused by the following: Oil on the part, Uneven wetting of the parts when dying impurities, Local overheating by polishing, Gas bubbles on anodize pores. I just did two lowers this weekend both with extensive prep and I still had spots on one of the lowers. The only thing I did differently between the two was agitate the dye. I did this by grabbing the lower and swishing it around every two minutes. My Line up: Bead Blast lowes Hand wash 200 degree caswell degreaser 5min full rinse Lye Etch 2min Full Rinse 110 degree Caswell De-Ox de-Smut 3 min Full Rinse Anodise 2.5 amps for 90 min agitate with fish tank pump Neutralize in baking soda and water Full rinse Dye 30 min at room temp agitate every 2 min Full rinse Seal in boiling water for 5 min. This is my second attempt and I am much happier this time. The first time I did not do enough prep. I will try and post some pictures tonight when I get home. I had scrubbed them pretty well with detergent and water and rinsed pretty good before they were etched in the lye. It was my understanding that the etching process would be the final clean before the anodize bath. I didn't use any desmut solution as you did either. And I didn't do anything such as the neutralizing in the baking soda and water.....the parts went from the anodize to rinse then into the dye. About 20 minutes in the dye then sealed in boiling water for 30 minutes. An aquarium pump will be added to the anodize bath next time to agitate. Did you use the Caswell dye or the RIT dye? I look forward to seeing your pictures. Dale |
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OP do you use anything to agitate the water while anodizing? No sir I did not agitate in the anodize bath.....an aquarium pump will be used next time tho. I also ordered a better power supply this morning but have yet to order the Caswell dye. The biggest hurdle I see is keeping the anodize bath in the temperature range that is required. I used ice around the bucket to cool it down...but it is real easy to overshoot and get the mixture too cold. Have to think about some better solution to that problem...some sort of chiller. |
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PacMan....How did you deal with the temperature issue?
The ice method is not all that good as I can see. I kept the water and acid in the house at 70 degrees before starting......but with temperatures in high 80's to low 90's it doesn't take too long foe the water to heat up. Using ice around the bucket is hit and miss at best. |
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I did not use caswell or rit dye. I used some random dye I found on ebay for like $10. The caswell dye is too expensive. Below are some pics. If you look close at the billet one you can see some of the dots. They were much worse when I first took it out of the dye. Caswell also recommends re-anodizing a little and re-dying (If you haven't sealed it yet). So I hooked the billet one back up for 20 minutes and then dyed again. As far as the temp if you anodize at low current it does not get hot. I ran the power supply at a constant 2.5 amps.
Billet 6061 
Forged 7075 with dye agitation. 
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I did not use caswell or rit dye. I used some random dye I found on ebay for like $10. The caswell dye is too expensive. Below are some pics. If you look close at the billet one you can see some of the dots. They were much worse when I first took it out of the dye. Caswell also recommends re-anodizing a little and re-dying (If you haven't sealed it yet). So I hooked the billet one back up for 20 minutes and then dyed again. As far as the temp if you anodize at low current it does not get hot. I ran the power supply at a constant 2.5 amps. Billet 6061 http://img.photobucket.com/albums/v365/pacman1/IMG_20150601_184959.jpg http://img.photobucket.com/albums/v365/pacman1/IMG_20150601_185036.jpg Forged 7075 with dye agitation. http://img.photobucket.com/albums/v365/pacman1/IMG_20150601_184954.jpg http://img.photobucket.com/albums/v365/pacman1/IMG_20150601_185012.jpg Wow...yours came out real nice sir.... If you could find the dye and send me the link I would appreciate it. My current was moving around quite a bit...I'll have better control with the new power supply. Your surface prep is a lot nicer than mine also...I was in too much of a hurry....I'll re-do mine and work on the prep more. |
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Wow...yours came out real nice sir.... If you could find the dye and send me the link I would appreciate it. My current was moving around quite a bit...I'll have better control with the new power supply. Your surface prep is a lot nicer than mine also...I was in too much of a hurry....I'll re-do mine and work on the prep more. Thanks, this was my second attempt. My first attempt I only bead blasted and then anodized with a battery charger. I'll post a couple pics below. I looked for the guy who sold me the dye and he is no longer listing on eBay, I did find this stuff it looks pretty good. http://www.ebay.com/itm/Black-BK-Super-Anodizing-Dye-2-Gallons-/231579370689?pt=LH_DefaultDomain_0&hash=item35eb34c4c1 If your current is moving around a bunch you may have a bad connection. Your surface prep sounds about the same as mine minus the de-smut. I pretty sure this is an important step if you do a lye etch. That black layer that forms after the etch is keeping you from growing a good anno layer. Besides the caswell stuff (which is really good) you can also use pool PH down. You want a 10% concentration of nitric acid. (Technaflora ph down) Here is a couple pics of the billet receiver after my first attempt to anodize. 
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I did not use caswell or rit dye. I used some random dye I found on ebay for like $10. The caswell dye is too expensive. Below are some pics. If you look close at the billet one you can see some of the dots. They were much worse when I first took it out of the dye. Caswell also recommends re-anodizing a little and re-dying (If you haven't sealed it yet). So I hooked the billet one back up for 20 minutes and then dyed again. As far as the temp if you anodize at low current it does not get hot. I ran the power supply at a constant 2.5 amps. Billet 6061 http://img.photobucket.com/albums/v365/pacman1/IMG_20150601_184959.jpg http://img.photobucket.com/albums/v365/pacman1/IMG_20150601_185036.jpg Forged 7075 with dye agitation. http://img.photobucket.com/albums/v365/pacman1/IMG_20150601_184954.jpg http://img.photobucket.com/albums/v365/pacman1/IMG_20150601_185012.jpg That looks nice! |
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Using an aquarium pump and air stone helps keep the acid cool too. I use a larger plastic container with a 5 gal bucket inside and fill the outside with water/ice as well.
Here's my process, but I don't use any dye or seal and Gunkote afterwards. I've been thinking about dying the next two. Do not let part dry anytime during the anodizing process steps 1-4. 1.One day prior to anodizing - Add 1 part battery acid (H2SO4) to 3 parts DI H2O. Slowly add acid to H2O. 2 qts battery acid, 1 ½ gal DI water. The solution needs to cool down before anodizing. 2.Degrease – materials: dish soap, Purple Power or Greased Lightening, acetone Wash with Purple Power, rinse tap water, wash with dish soap, rinse tap water then DI H2O rinse, dry, soak in acetone 10 minutes 3.Etch – Red Devil Lye 2 tablespoons per gallon DI H2O. 120g/L -Attach AL rod to lower to use as a handle. -NaOH bath 2-5 minutes, agitate every so often until a greyed/blk. -Spray DI H2O to rinse off over NaOH bath. -DI water bath covering lower, agitate, pour off and change water let soak for a few minutes. 4.Desmut – 10% Nitric Acid bath (Techniflora pH down) -3-5 minute turns white. Agitate in bath. -Spray bottle with DI water -DI water bath covering lower, agitate 5.Anodize -H2SO4 should be at 69° - 72°F, use glass aquarium thermometer. -Replace short AL rod on lower with longer rod for anodizing. -Battery charger - Negative (cathode) to lead/AL in bath, Positive (anode) to AR lower AL rod. Start at 6V for 5 minutes (mine held at 2A). Switch to 12V for remainder of time (mine held at 3.5A). Read amperage and calculate time. If power supply reads 3.5A: 720/3.5 = 206 amp min 81 sq in/144 in/ft = .5625 sq ft (81 sq in is the lower surface area) 206 x 0.5625 = 116 min in tank @ 3.5A Spray bottle with DI water over tank Soak in DI water, change water soak several minutes Dry several days before Gunkote process |
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Using an aquarium pump and air stone helps keep the acid cool too. I use a larger plastic container with a 5 gal bucket inside and fill the outside with water/ice as well. Here's my process, but I don't use any dye or seal and Gunkote afterwards. I've been thinking about dying the next two. Do not let part dry anytime during the anodizing process steps 1-4. 1.One day prior to anodizing - Add 1 part battery acid (H2SO4) to 3 parts DI H2O. Slowly add acid to H2O. 2 qts battery acid, 1 ½ gal DI water. The solution needs to cool down before anodizing. 2.Degrease – materials: dish soap, Purple Power or Greased Lightening, acetone Wash with Purple Power, rinse tap water, wash with dish soap, rinse tap water then DI H2O rinse, dry, soak in acetone 10 minutes 3.Etch – Red Devil Lye 2 tablespoons per gallon DI H2O. 120g/L -Attach AL rod to lower to use as a handle. -NaOH bath 2-5 minutes, agitate every so often until a greyed/blk. -Spray DI H2O to rinse off over NaOH bath. -DI water bath covering lower, agitate, pour off and change water let soak for a few minutes. 4.Desmut – 10% Nitric Acid bath (Techniflora pH down) -3-5 minute turns white. Agitate in bath. -Spray bottle with DI water -DI water bath covering lower, agitate 5.Anodize -H2SO4 should be at 69° - 72°F, use glass aquarium thermometer. -Replace short AL rod on lower with longer rod for anodizing. -Battery charger - Negative (cathode) to lead/AL in bath, Positive (anode) to AR lower AL rod. Start at 6V for 5 minutes (mine held at 2A). Switch to 12V for remainder of time (mine held at 3.5A). Read amperage and calculate time. If power supply reads 3.5A: 720/3.5 = 206 amp min 81 sq in/144 in/ft = .5625 sq ft (81 sq in is the lower surface area) 206 x 0.5625 = 116 min in tank @ 3.5A Spray bottle with DI water over tank Soak in DI water, change water soak several minutes Dry several days before Gunkote process Thanks Blowout for posting your method.... I was hung up a little with the math...missing an accurate go by for the square inches on the lower. Mine was in the bath for right at 2 hrs. Hopefully with the new power supply I can just set and forget the amperage after that and not worry about it. |
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Good info on the 720 rule Blowout. Here is a link to a nice 720 calculator. 720 Rule Calculator
After you reach the peak voltage or recommended time the anodized layer actually begins to dissolve. |
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How clean was your tub/container before you started anodizing? Could be some leftover release agent in your plastic tub from the manufacturing process. Bucket had not been used prior and had been only rinsed with tap water a couple of times to remove some dust. It was completely dry for a day or two before using. |
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Thanks Blowout for posting your method.... I was hung up a little with the math...missing an accurate go by for the square inches on the lower. Mine was in the bath for right at 2 hrs. Hopefully with the new power supply I can just set and forget the amperage after that and not worry about it. Quoted:
Quoted:
Using an aquarium pump and air stone helps keep the acid cool too. I use a larger plastic container with a 5 gal bucket inside and fill the outside with water/ice as well. Here's my process, but I don't use any dye or seal and Gunkote afterwards. I've been thinking about dying the next two. Do not let part dry anytime during the anodizing process steps 1-4. 1.One day prior to anodizing - Add 1 part battery acid (H2SO4) to 3 parts DI H2O. Slowly add acid to H2O. 2 qts battery acid, 1 ½ gal DI water. The solution needs to cool down before anodizing. 2.Degrease – materials: dish soap, Purple Power or Greased Lightening, acetone Wash with Purple Power, rinse tap water, wash with dish soap, rinse tap water then DI H2O rinse, dry, soak in acetone 10 minutes 3.Etch – Red Devil Lye 2 tablespoons per gallon DI H2O. 120g/L -Attach AL rod to lower to use as a handle. -NaOH bath 2-5 minutes, agitate every so often until a greyed/blk. -Spray DI H2O to rinse off over NaOH bath. -DI water bath covering lower, agitate, pour off and change water let soak for a few minutes. 4.Desmut – 10% Nitric Acid bath (Techniflora pH down) -3-5 minute turns white. Agitate in bath. -Spray bottle with DI water -DI water bath covering lower, agitate 5.Anodize -H2SO4 should be at 69° - 72°F, use glass aquarium thermometer. -Replace short AL rod on lower with longer rod for anodizing. -Battery charger - Negative (cathode) to lead/AL in bath, Positive (anode) to AR lower AL rod. Start at 6V for 5 minutes (mine held at 2A). Switch to 12V for remainder of time (mine held at 3.5A). Read amperage and calculate time. If power supply reads 3.5A: 720/3.5 = 206 amp min 81 sq in/144 in/ft = .5625 sq ft (81 sq in is the lower surface area) 206 x 0.5625 = 116 min in tank @ 3.5A Spray bottle with DI water over tank Soak in DI water, change water soak several minutes Dry several days before Gunkote process Thanks Blowout for posting your method.... I was hung up a little with the math...missing an accurate go by for the square inches on the lower. Mine was in the bath for right at 2 hrs. Hopefully with the new power supply I can just set and forget the amperage after that and not worry about it. Use this: 720/(your amps) x 0.5625 = minutes to keep in the bath If you were at 3.5A it's 116 mins and 2 hrs would be close enough. I re-read your first post and agree with another you could be loosing connectivity to the lower during anodizing. At 2A for the last hour, you might not be fully anodized. Take an ohm meter and check to see if there is connectivity across the surface of the lower. If there is, it isn't anodized. Not to worry... just go back and reanodize from the beginning. Degrease, lye, etc. The lye removes the previous anodized surface. I find when I start anodizing at 6V the meter pins and then slowly backs down over a few minutes. (I can't change amps, only volts on my charger) Then I switch to 12v and it jumps up some and slowly settles in around 5 minutes at 3.5A. Using a 1/4" AL rod and threading it to 1/4-28, it fits into the pistol grip screw position and you'll have a solid connection. I tighten with pliers too. If your water is getting hot, you could always use an air pump and put it in an ice chest with the lid not fully closed and the pump where it stays dry, so cold air is pumped into the acid bath. That should keep the temp down on even on a hot day. I do mine in the garage where it stays cooler on a hot day. Good luck with it. |
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Use this: 720/(your amps) x 0.5625 = minutes to keep in the bath If you were at 3.5A it's 116 mins and 2 hrs would be close enough. I re-read your first post and agree with another you could be loosing connectivity to the lower during anodizing. At 2A for the last hour, you might not be fully anodized. Take an ohm meter and check to see if there is connectivity across the surface of the lower. If there is, it isn't anodized. Not to worry... just go back and reanodize from the beginning. Degrease, lye, etc. The lye removes the previous anodized surface. I find when I start anodizing at 6V the meter pins and then slowly backs down over a few minutes. (I can't change amps, only volts on my charger) Then I switch to 12v and it jumps up some and slowly settles in around 5 minutes at 3.5A. Using a 1/4" AL rod and threading it to 1/4-28, it fits into the pistol grip screw position and you'll have a solid connection. I tighten with pliers too. If your water is getting hot, you could always use an air pump and put it in an ice chest with the lid not fully closed and the pump where it stays dry, so cold air is pumped into the acid bath. That should keep the temp down on even on a hot day. I do mine in the garage where it stays cooler on a hot day. Good luck with it. Quoted:
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Using an aquarium pump and air stone helps keep the acid cool too. I use a larger plastic container with a 5 gal bucket inside and fill the outside with water/ice as well. Here's my process, but I don't use any dye or seal and Gunkote afterwards. I've been thinking about dying the next two. Do not let part dry anytime during the anodizing process steps 1-4. 1.One day prior to anodizing - Add 1 part battery acid (H2SO4) to 3 parts DI H2O. Slowly add acid to H2O. 2 qts battery acid, 1 ½ gal DI water. The solution needs to cool down before anodizing. 2.Degrease – materials: dish soap, Purple Power or Greased Lightening, acetone Wash with Purple Power, rinse tap water, wash with dish soap, rinse tap water then DI H2O rinse, dry, soak in acetone 10 minutes 3.Etch – Red Devil Lye 2 tablespoons per gallon DI H2O. 120g/L -Attach AL rod to lower to use as a handle. -NaOH bath 2-5 minutes, agitate every so often until a greyed/blk. -Spray DI H2O to rinse off over NaOH bath. -DI water bath covering lower, agitate, pour off and change water let soak for a few minutes. 4.Desmut – 10% Nitric Acid bath (Techniflora pH down) -3-5 minute turns white. Agitate in bath. -Spray bottle with DI water -DI water bath covering lower, agitate 5.Anodize -H2SO4 should be at 69° - 72°F, use glass aquarium thermometer. -Replace short AL rod on lower with longer rod for anodizing. -Battery charger - Negative (cathode) to lead/AL in bath, Positive (anode) to AR lower AL rod. Start at 6V for 5 minutes (mine held at 2A). Switch to 12V for remainder of time (mine held at 3.5A). Read amperage and calculate time. If power supply reads 3.5A: 720/3.5 = 206 amp min 81 sq in/144 in/ft = .5625 sq ft (81 sq in is the lower surface area) 206 x 0.5625 = 116 min in tank @ 3.5A Spray bottle with DI water over tank Soak in DI water, change water soak several minutes Dry several days before Gunkote process Thanks Blowout for posting your method.... I was hung up a little with the math...missing an accurate go by for the square inches on the lower. Mine was in the bath for right at 2 hrs. Hopefully with the new power supply I can just set and forget the amperage after that and not worry about it. Use this: 720/(your amps) x 0.5625 = minutes to keep in the bath If you were at 3.5A it's 116 mins and 2 hrs would be close enough. I re-read your first post and agree with another you could be loosing connectivity to the lower during anodizing. At 2A for the last hour, you might not be fully anodized. Take an ohm meter and check to see if there is connectivity across the surface of the lower. If there is, it isn't anodized. Not to worry... just go back and reanodize from the beginning. Degrease, lye, etc. The lye removes the previous anodized surface. I find when I start anodizing at 6V the meter pins and then slowly backs down over a few minutes. (I can't change amps, only volts on my charger) Then I switch to 12v and it jumps up some and slowly settles in around 5 minutes at 3.5A. Using a 1/4" AL rod and threading it to 1/4-28, it fits into the pistol grip screw position and you'll have a solid connection. I tighten with pliers too. If your water is getting hot, you could always use an air pump and put it in an ice chest with the lid not fully closed and the pump where it stays dry, so cold air is pumped into the acid bath. That should keep the temp down on even on a hot day. I do mine in the garage where it stays cooler on a hot day. Good luck with it. Thank you for the info...I will try again as soon as parts and supplies arrive. |
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Use this: 720/(your amps) x 0.5625 = minutes to keep in the bath If you were at 3.5A it's 116 mins and 2 hrs would be close enough. I re-read your first post and agree with another you could be loosing connectivity to the lower during anodizing. At 2A for the last hour, you might not be fully anodized. Take an ohm meter and check to see if there is connectivity across the surface of the lower. If there is, it isn't anodized. Not to worry... just go back and reanodize from the beginning. Degrease, lye, etc. The lye removes the previous anodized surface. I find when I start anodizing at 6V the meter pins and then slowly backs down over a few minutes. (I can't change amps, only volts on my charger) Then I switch to 12v and it jumps up some and slowly settles in around 5 minutes at 3.5A. Using a 1/4" AL rod and threading it to 1/4-28, it fits into the pistol grip screw position and you'll have a solid connection. I tighten with pliers too. If your water is getting hot, you could always use an air pump and put it in an ice chest with the lid not fully closed and the pump where it stays dry, so cold air is pumped into the acid bath. That should keep the temp down on even on a hot day. I do mine in the garage where it stays cooler on a hot day. Good luck with it. Quoted:
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Using an aquarium pump and air stone helps keep the acid cool too. I use a larger plastic container with a 5 gal bucket inside and fill the outside with water/ice as well. Here's my process, but I don't use any dye or seal and Gunkote afterwards. I've been thinking about dying the next two. Do not let part dry anytime during the anodizing process steps 1-4. 1.One day prior to anodizing - Add 1 part battery acid (H2SO4) to 3 parts DI H2O. Slowly add acid to H2O. 2 qts battery acid, 1 ½ gal DI water. The solution needs to cool down before anodizing. 2.Degrease – materials: dish soap, Purple Power or Greased Lightening, acetone Wash with Purple Power, rinse tap water, wash with dish soap, rinse tap water then DI H2O rinse, dry, soak in acetone 10 minutes 3.Etch – Red Devil Lye 2 tablespoons per gallon DI H2O. 120g/L -Attach AL rod to lower to use as a handle. -NaOH bath 2-5 minutes, agitate every so often until a greyed/blk. -Spray DI H2O to rinse off over NaOH bath. -DI water bath covering lower, agitate, pour off and change water let soak for a few minutes. 4.Desmut – 10% Nitric Acid bath (Techniflora pH down) -3-5 minute turns white. Agitate in bath. -Spray bottle with DI water -DI water bath covering lower, agitate 5.Anodize -H2SO4 should be at 69° - 72°F, use glass aquarium thermometer. -Replace short AL rod on lower with longer rod for anodizing. -Battery charger - Negative (cathode) to lead/AL in bath, Positive (anode) to AR lower AL rod. Start at 6V for 5 minutes (mine held at 2A). Switch to 12V for remainder of time (mine held at 3.5A). Read amperage and calculate time. If power supply reads 3.5A: 720/3.5 = 206 amp min 81 sq in/144 in/ft = .5625 sq ft (81 sq in is the lower surface area) 206 x 0.5625 = 116 min in tank @ 3.5A Spray bottle with DI water over tank Soak in DI water, change water soak several minutes Dry several days before Gunkote process Thanks Blowout for posting your method.... I was hung up a little with the math...missing an accurate go by for the square inches on the lower. Mine was in the bath for right at 2 hrs. Hopefully with the new power supply I can just set and forget the amperage after that and not worry about it. Use this: 720/(your amps) x 0.5625 = minutes to keep in the bath If you were at 3.5A it's 116 mins and 2 hrs would be close enough. I re-read your first post and agree with another you could be loosing connectivity to the lower during anodizing. At 2A for the last hour, you might not be fully anodized. Take an ohm meter and check to see if there is connectivity across the surface of the lower. If there is, it isn't anodized. Not to worry... just go back and reanodize from the beginning. Degrease, lye, etc. The lye removes the previous anodized surface. I find when I start anodizing at 6V the meter pins and then slowly backs down over a few minutes. (I can't change amps, only volts on my charger) Then I switch to 12v and it jumps up some and slowly settles in around 5 minutes at 3.5A. Using a 1/4" AL rod and threading it to 1/4-28, it fits into the pistol grip screw position and you'll have a solid connection. I tighten with pliers too. If your water is getting hot, you could always use an air pump and put it in an ice chest with the lid not fully closed and the pump where it stays dry, so cold air is pumped into the acid bath. That should keep the temp down on even on a hot day. I do mine in the garage where it stays cooler on a hot day. Good luck with it. You can purchase the correct size socket head cap screw for the pistol grip in aluminum. It would save a lot of work. LINK |
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I think I spent $10 for a 3' piece of 1/4" AL rod at Ace. Then used a die to thread it 1/4-28. I reuse the same rod over and over. It hasn't anodized on the threads after 3 lowers.
I also cut some smaller rods and drilled a hole in a 2x6 to make stands for spraying Gunkote. You can use it for a handle on the part too. Works better than hanging them. You can't etch anodized metal, so I always use bare metal 80% lowers. |
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