As I understand it, cooking helps activate the gluten (think the stringy-ness that forms in bread dough when you pull it apart.)  That adds strength to the glue.   So non-cooked is still glue, but without the reinforcing strings of gluten.

In my paste, which is mostly methyl cellulose, I add a small amount of white glue (PVA glue) with laundry starch which forms long-chain polymers.  When mixed within the methyl cellulose ... it gives a similar stringy-ness effect. 

Uncooked flour and water paste is what Dan Reeder uses, however ... it does add a hardness (I think from the undissolved flour) ... `

-- b

The most common source of Methyl Cellulose is Elmer's Art Paste. Pretty readily available at most art stores or on Amazon. A box is under $5 and mixes up a gallon. Other sources are book binding supply companies.
Joey

Last edited by paper soup (2012-11-13 00:31:02)

koko,

Elmers art paste works fine, but I'm partial to Dow's Methocel A4M which I get in College Park at Bookmakers ...  http://www.bookmakerscatalog.com/catalo … esives.htm

Because I pick it up, I don't pay shipping charges, and without the shipping it's close enough in price, that I don't worry about the difference.  (One 1/2lb container makes about 2.5 gallons of paste). 

[My recipe used to be 6 MC : 1 Glue : 1 Starch ... it still is if using white glue other than 'Elmers New Improved' ... the new improved version of Elmers has more solids so it reacts more to the starch.  I now add only 1/3 part of starch to 1 part Elmers, and start with 6 parts MC, adding more to get the desired consistency if needed.  ]

Methyl Cellulose is used as a coating agent in foods / medicines.  My theory about what's happening in my paste is that when I mix the white glue and starch forming the long-chain polymers ... that starts to clump like melted cheese ... so initially I have a big wad of glue and starch around my stirring stick.  But as I continue to stir it smooths out and disperses -- leaving me with glue that resembled stringy egg whites.

The egg white consistency spreads easily -- allows me to slide pasted papers if I need to adjust something, and dries with a little more reinforcement from the polymer chains -- which reinforce the locking paper fibers themselves. 

That's my theory anyway.  Haven't looked at any of it under a microscope, but I did do comparison tests when I was first testing glue recipes ... and liked this one the best. 

I hope that answers your question ... if not, ask again.  : )

-- b

Last edited by bmaskmaker (2012-11-13 17:23:05)

Cooking makes flour-based adhesive stickier.  Without the heat, the tiny bits of flour just sit there, but with the addition of heat, they swell and get stickier.

It's simple and nontoxic, as long as you don't have creatures around that would be attracted to a food product.  Don't dawdle -- get your project made, dried, decorated and sealed.  Keep it out of the reach of pets. *rolling eyes*

Sue

Paper soup:  a lot.  The usual recipe is 1 Tbsp. MC mixed into 2 cups of cold water, and let set a few hours or overnight.  DO NOT use hot water!

Sue

Paper,

I make my batches in those 1/2 gallon Mix-A-Lot buckets ... and I get about 5 1/2 batches (so ~ 2 1/2 Gallons).  And, like the Elmers version, as long as your bucket is clean it doesn't 'go bad' because there's nothing in it to spoil.  (Once I mix my paste which has some laundry starch, that can go off, but straight methyl cellulose lasts a really long time.)

It comes in different viscosities.  I get the A4M which is more viscous ... I find that saves me a bit, because I can thin it with water if I want/need. 

: )

-- b

Last edited by bmaskmaker (2012-11-24 20:55:07)

: )

Yes, definitely covered.  I tried to see if I could use dried mc as a clear casting material and left some to dry in an ice cube mold.  Definitely dries out.  Didn't work as casting material ... too thin and flimsy.  : )

-- b