potassium hydroxide or KOH

[troy]

have been getting my KOH from braintan.com (oregon), but am looking for somewhere over here to get it from.
Any body got any ideas.

Also I am getting confused about all these axes avaliable out there - All I am looking for is a small hand axe that cuts , not splits wood for use in making my bow staves - any body know which axe I should be looking at?
Cheers

 

[ChrisKavanaugh]

Is this for harvesting the wood or doing rough finishing? If it's rough work a carpenter's hatchet. This is merely a scaled down broadaxe with a plane or chisel blade.

 

[Eric_Methven]

What are you using the potassium hydroxide for? Will sodium hydroxide not do? If so any DIY place such as B&Q or Homebase will have it labled as caustic soda.

If you want to make your own potassium hydroxide to use as lye for making soap, it's easy to make from wood ash and water. It's the old backwoods way of doing it before there were any shops. Let me know and I'll give you the technique for making it (and Grandma's lye soap recipe as well if you want.)

As for the axe, I'd recommend the Gransfors Bruks carving axe designed by Willy Sundkvist. It'll slice large or small chunks of your staves and leave a clean finish behind it's so sharp. I use mine in conjunction with a drawknife and spokeshave to make ash and yew longbows.

Eric

 

[troy]

I'm using the KOH to help in the process of dehairing skins - if sodium hydroxide can do the same as KOH, then that is great, but I know nothing about chemicals so please confirm if it could do the same job. I could and would use ash but unfortunatly the amounts I would need and the space I have do not make that feasible.

Cheers for the axe idea, I was looking at those axes, but was unsure which would best be suited for the job. I make rawhide backed meare heath bows out of any hard wood I can get and like to use an axe over a drawknife on the belly as I feel I have more control.

 

[hootchi]

I'm doing chemical physics at uni and NaOH is chemically the same as KOH (alkaline) but KOH is stronger, dissociates better in water, so a slightly stronger solution of NaOH and longer soak may be needed to strip the hairs.

All chemicals are dangerous and to be treated with caution as both are harmful and corrosive.

 

[Tantalus]

something niggling at the back of my mind here but can not remember

NaOH (sodium hydroxide) solid is hygroscopic, absorbs water from the air quite strongly, also heats up a fair bit while it does so

Needs airtight storage

Is this the same as KOH?

Tant

 

[troy]

Ok, This is where I demonstrate my ignoronce of Chemistry, but just to confirm NaOH is Sodium Hydroxide, Yes, and is labeled as Caustic Soda in the shops.

One other thing - is it safe to empty it out in my garden once used?

Thanks for all your help here. Cheers

 

[Eric_Methven]

Caustic soda (sodium hydroxide) is stronger than potassium hydroxide. You get potassium hydroxide from running water through wood ash and would have been the traditional way of dehairing a skin, just as it was the traditional way of making soap. You can certainly use sodium hydroxide to dehair but make a weaker solution of lye and wear rubber gloves and use eye protection.

When you are finished with it, you can safely pour the solution down the outside drain (filter the hair out first). This solution was designed to be drain cleaner anyway so it'll shift any grease out there.

Eric

 

[Realgar]

Needs airtight storage

Is this the same as KOH?

Tant

Not quite the same - NaOH will go as a far forming a solution ( if you can call a highly corrosive opaque syrup a solution ) from atmospheric water. KOH isn't that bad but it does absorb CO2 from the air - our lab grade stuff needs replacing once a year or so ( depending on how many times it's been opened ) as the pearls go grey with a thick coating of potassium carbonate.

Can anyone recall the old method for going from wood ash lye to caustic soda?

Both get excessively hot on mixing with water and both will strip your skin
Realgar

 

[troy]

After reading all the lovely stuff about this caustic soda and the fact that my kids join in now and again, I had a brain wave last night (should be another along in twenty years) and rang a few local chemical manufacturers for the fish trade and most sell it - so problem solved - cheers for the input.