Bokakob 54mm x 150cm column

[pulsetech]

I know the reflux chamber needs to be empty, i was reffering to puting the spp in the column, i thought that you need to do it from the top opening and the lower plate would retain some of the SPPs and redirect them to the output tube...

With a non-modular Bokakob dual slant plate column you will need a top retainer just below the bottom plate, fill from the bottom, and use a bottom retainer... I have had decent luck using a piece of SS scrubber at each end of my tall reflux column to hold the SPP in place... Haven't lost it into the boiler yet...!!!

Hope you were touching wood when you typed that Rad.

[apdb]

Hardy har har

[bionut]

So my small package from China arrived.
Now i got the compression fittings, the needle valve and the tri clamp that i need.









And the union that i will use to detach the liquor chiller when i don't need it or what to use it for something else. How can i now if the gasket is made out of PTFE or regular plastic? It looks like the same material the tri clamp gasket is made off. Is there any test to find this? If not probably i need to find some PTFE sheet and cut a gasket from it...
I also bought a coupling that can be used instead of the union.





Couple of questions:
How hard should it be to rotate the needle valve? It is pretty hard now, should i open it and grease it with something or what?
How much to tighten the triclamp? When i know it is tight enough (before i have vapour leaks :LOL: )

I am getting close to my cleaning run, just have to clean the SPSs (have grease on them) and etch them.

[still_stirrin]

g

...How hard should it be to rotate the needle valve?...

Not hard.

Try loosening the bonnet (the top nut on the stem), then twist the stem and see how you are. Sometimes those are over tightened and hard to turn. If its too tight it can actually damage the seal inside.
ss

[Danespirit]

On one of the pictures the compressionfittings look like brass, but they are stainless..funny how light changes things.
It all looks similar to what i use. The gasket in the ferrule is definatly PTFE.
The one in the union...ahh...it could be nylon, which i suspect it is..!
PTFE, will be more ridgid as nylon. If you can make a small mark with your fingernail in it...it is nylon and should be replaced.
You can also look at the edges, the PTFE are clean trimmed, nylon might have small fibrils hanging on the edge.
Also PTFE is real white like chalk, nylon usually is a little more "transparent" to look at.
As Still stirrin suggested, try to loosen the top of the valve.
Mine is similar, just male threaded and was a bit hard to turn...taking it appart and refitting it, solved the problem.

[Hound Dog]

As for the tri clamps, YMMV. I have to tighten the crap out of the ones at the base of my column. I find that if it is leaking a bit, I tap around the clamp with a small hammer seating it onto the ferrule tightly then tighten the screw some more. A little soft PTFE tape around the harder gasket might help to start with but why do it the easyway?

[bionut]

If that's the case why not take a silicon gasket and wrap it in teflone tape?

[Danespirit]

Hound Dog...try and place some very fine emerycloth, made for grinding with water on it (grit 800 or 1000) on a even surface.
Polish/grind your ferrule in circular motions....it should solve the problem.
I've done so on all my ferrules, as they tend to warp a bit from the TIG welding.
Bionut...if you wrap a silicone gasket with PTFE tape, there is still a chance of exposure (even if it's remote).
You are better off using safe materials like cork or uncoloured cardboard...

[Hound Dog]

Hound Dog...try and place some very fine emerycloth, made for grinding with water on it (grit 800 or 1000) on a even surface.
Polish/grind your ferrule in circular motions....it should solve the problem.
I've done so on all my ferrules, as they tend to warp a bit from the TIG welding.
Bionut...if you wrap a silicone gasket with PTFE tape, there is still a chance of exposure (even if it's remote).
You are better off using safe materials like cork or uncoloured cardboard...

Yea, I figured it was a bit warped because getting it to go into a 3" type L pipe was a bitch! The BFH (big f'ing hammer) and a block of wood I used to drive it in probably did it no good. If I were to do it again I would use the ferrules that go on the outside of the pipe that DAD300 posted about right after my last build.....

[bionut]

Hi guys, my project was in a stand by for a few months because i was busy with my wedding.







I think i have a problem with the packing, after i etched them in ferric chloride this is how it looks:



Is it rust or just ferric chloride rezidue left over because i didn't rinse it well? Can i suppose that the rust will be cleaned on the cleaning run or i need to clean them myself (how?) or make another packing?

[Odin]

Dont etch.

You are not looking for surface area but for something to hold reflux so you can run her fast instead of slow.

Odin.

[Bushman]

Did I miss it but what is your packing made from? I etched my copper packing and haven't noticed a problem after several years. On another note I hope your not collecting your product in that plastic jug.

[bionut]

It's stainless steel wire, 304 or 316, can't remind. I am guessing that i didn't neutralized and rinsed the ferric chloride good enough, so that may be just dried ferric chloride. Any idea about how can i test this?

I alrdeady etched the SPP, not much i can do about this now.
The plastic canister is used for fermenting my beer, eventualy my alcohol wash too

[rad14701]

What grade of SS wire did you use to make your SPP...??? Do you still have the specifications from the wire spool...??? Either the SS grade was poor or the SPP was in the ferric chloride soak for too long... Now might be a good time to try marbles or scoria (lava rock) for structured packing...

Posted the same time as bionut...

[Danespirit]

+1 Odin
What a shame with the SSP..
The grey stuff i see where your slantplates are, is residue from the soldering i assume..?
Did you solder the takeoff to the column?
If so, i would suggest another solution.
As you have attached it to the column, you will get heattransfer to it, which is bad...cause you want the heat away from your product.
It also works the other way around and you will get a cold spot on your column, were the takeoff is attached to it.
I do get the point..you probably did this to get the takeoff more rigid.
If you don't want a moveable support for the takeoff, clamp it to the column with some rubber between the clamp and column.
Attach the other end of the clamp to your Liebig in the same manner.
You would almost eliminate heattransfer between the takeoff/Liebig and column, but still get a sturdy connection (and it could be removed, if desired)
Your rig will also benefit from insulation.
It should be insulated all the way up to the first slantplate, from there and up you want to condense into liquid....thus no more insulation.

Happy new year..

[cranky]

I'm not sure what ferric chloride would do to stainless steel but to me it looks like rust. Could it be the SS needed pasivated after etching?

[bionut]

Yes, the whie stuff is some sort of oxide from the soldering. It can be whipes easily..
I didn't think about the heat transfer from the column to the output. I soldered it to male it more rigid, as it seems that the output soldering spot can break under the weight of the output and liebig.

Can i salvage the SPP somehow?

[cranky]

Can i salvage the SPP somehow?

I am the first to admit I know very little about this sort of stuff so I don't know what my advice is really worth. That said from what I can find in the interweb a nitric acid bath might do the trick of both removing the rust and passivating. If it were me I think I would get some nitric acid and try it on a sample and see what happens. Hopefully some of the smarter people here will chime in if my suggestion is not a good one.

[Hound Dog]

Looks pretty ruined.?

[bearriver]

I am under the impression that some acids will eat the nickel off the outside of the stainless. Bleach would be one such acid that is reported to do that. I wouldn't be surprised to learn there are others. In such cases the iron will be exposed then rust.

So if that is what happened to you, then you might be able to repassivate as Crancky stated. Nitric acid is dangerous so you may want to consider citric acid instead. Its much safer and applicable for the job. Here is a wiki link with some info about the passivation of stainless.

Edit: nevermind , I can't get the link to work. You can find it by googling "Stainless passivation" then click on the wiki result.

[ThomasBrewer]

The photos in this thread have been extremely helpful for newbs like myself. Would it be possible to have a mod download the photos from Flickr and edit the posts to point back to hosting here? The demise of Photobucket really ruined a wealth of information in other threads.

[bionut]

I am glad you found the photos helpful. I still use this column and with 1 meter of SPP i can collect at +96% abv. Great design!

[Iulistoi]

Nice equipment, great work!

We wait you to make more alcohol, describe the operation instructions and post new pics.