Best anodizing guide?

**JOGARA** · 02-10-2017

Just tried one of these in a 500ml glass jar and it worked pretty well.

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Took a good 10-15 mins to get up to temperature so would expect a lot longer with 5l tubs.
Runs at 12v and draws pretty much bang on 10A so 120watts.

Going to test wit 5L now!

**m_c** · 02-10-2017

The specific heat capacity of water is 4.184 joules/gram/deg, so to raise 5 litres of water from 20 to 80 degC, would take 1255200 joules (4.184 * 5000 * (80-20)), or 0.349 KWh. Now if you've only got 120W, that means it would take 2.91 hours (0.349 / 0.12) assuming you have zero heat loss.

However, unless you've got insulated containers, I'd doubt you'd ever get to 80degC.

**JOGARA** · 02-10-2017

Originally Posted by m_c

The specific heat capacity of water is 4.184 joules/gram/deg, so to raise 5 litres of water from 20 to 80 degC, would take 1255200 joules (4.184 * 5000 * (80-20)), or 0.349 KWh. Now if you've only got 120W, that means it would take 2.91 hours (0.349 / 0.12) assuming you have zero heat loss.

However, unless you've got insulated containers, I'd doubt you'd ever get to 80degC.

Pretty much spot on. Tried it for the hell of it and got the top third of the water to 50c/
The rest stayed at 16c (workshop room temp). That was nearly 1 hour.

I am thinking 1000w min really as I don't want to wait too long for it and once one puts the part into the bucket the temp will go down quite a bit. So need it to be fast enough to recover from that.

Wondering if something like this would work?
https://www.aliexpress.com/item/900W...809794841.html
Keeping in mind a 5L bucket is around 200-220mm tall?
Not sure if these are designed for water but should be okay as long as the top is kept above water line I believe.

**m_c** · 02-10-2017

With something like that, I'd be making sure they were well earthed, and powered via a good RCD.

Have you had a look at any of the youtube videos for ideas?
I've got these saved in my watch later list
https://www.youtube.com/watch?v=BtYHcsq7s5A
https://www.youtube.com/watch?v=GccTVfMiIIo
https://www.youtube.com/watch?v=TGi-nqNnENE

It's been a while since I watched them, so can't remember exactly what they covered, but they must of contained something worthwhile that I never deleted them after watching them..

**JOGARA** · 03-10-2017

Thinking about it.
Cleaner, Dye and Sealer don't care if they are in a metal container?
Why not just use stainless cooking pots and put them on those cheap hot plates?
http://www.ebay.co.uk/itm/Single-Ele...EAAOSw-K9ZIxN4

As variable knob too so could potentially not even need thermostat controller?

Obviously not put the acid/lye in these, they still need plastic containers.

**Zeeflyboy** · 03-10-2017

that's probably the way i'd do it personally yeah

**JOGARA** · 03-10-2017

Originally Posted by Zeeflyboy

that's probably the way i'd do it personally yeah

£11 for the hotplate, £8 for the 5L stainless pot. Total price is much better than Plastic tub plus heat element and controller...

**JOGARA** · 03-10-2017

**Desertboy** · 03-10-2017

Originally Posted by JOGARA

From what I read you don't want the acid hot at all. Both the etch and/or the anodizing tanks should be room temp as those processes get hot when reacting/putting amps though them.
The Desmut, Colour and Seal should be heated though...

Going off the Ron Newman guide that m_c sent be lists this;

Polish part using fine sand paper for shiny finish, or wire wool for matte (can also etch for a little longer for matte finish/hide imperfections)
Cleaner @ 140F 5 mins
Rinse (de-ionized water)
Etch in Lye for 10-30 seconds @ room temp
Rinse (de-ionized water)
Desmut @ room temp 1-3mins
Rinse (de-ionized water)
Anodize at room temp based off 720 rule
Rinse (de-ionized water)
Dye @ 140F for 15s-15m
Rinse (de-ionized water)
Seal @ 180F
Rinse (de-ionized water)
Hang to dry for 24 hours

Other guides I have seen do mostly the same procedure, though one suggested using "Sodium Bisulfate/Sodium Hydrogen Sulfate" instead of Sulfuric which I guess is safer?

As for heating the buckets, I like the one you linked, but I am limited on power in my current workshop. Wont be in my new one till end of November.
Pretty much can't draw more than 3000w in total.

Thinking of getting a couple 12v ones that I can then use one of these cheap controller boxes with. Safer too as those immersion ones don't always have earth on the metal case.
https://www.ebay.co.uk/itm/172822446...r=471604592191 (This is 220v ones yes, they do 12v too)

If you have a mains thermostat just tape the probe to the outside of the bucket accuracy will be good enough.

I use these
http://www.ebay.co.uk/itm/220V-10A-M.../142426824134?

daily very reliable never had one fail over 5 years.

**JOGARA** · 03-10-2017

Originally Posted by Desertboy

If you have a mains thermostat just tape the probe to the outside of the bucket accuracy will be good enough.

I use these
http://www.ebay.co.uk/itm/220V-10A-M.../142426824134?

daily very reliable never had one fail over 5 years.

I presume that as long as the temps are in the ballpark around 120-140F then it is okay? Don't have to be so bang on?

[edit]
Multi buy, 3 for 2 https://www.ebay.co.uk/itm/292039778...r=591027809178