which liquid cement?

Add me to the list of Tenax supporters. It is great stuff, bonds quickly and strongly and flows like H2O into seams.

Looking to my LAST half emptied Slater' s MEK-PAK liquid polystyrene cement bottle, all this hubbub about M.E.K. makes me a little bit nervous...I hope I could order some more from Slaters' M-O shop...!
It 's, so far, the BEST liquid cement I found on the market....Fluid, strong, and not too much smelly !

freefall,
Liquid cements should pose no real problem, since you are probably using them in very small amounts, and at a relatively infrequent pace. Make sure to leave the cap on when not in use. I would try to avoid paint and other materials containing the solvents toluene and methylene chloride. Continue to leave your window open; you are providing some very good dilution ventilation. If you have other specific questions, please don't hesitate to e-mail me. Just click on the name "styrene" and it will take you to my profile. From there, simply click on "email" and go for it.

Stinger,
Because the respone to your question was a little lengthy, I e-mailed you direct.

Gip Winecoff

Gip - With regard to MEK: I use lacquer thinner extensively in my wordworking projects, both to thin lacquers and to clean formica and melamine. I know that many lacquer thinners contain MEK, and I have been told that Ketones absorb readily into the blood stream, and that our kidneys cannot remove them. They just stay in the body. Is this true? I always avoid anything that contains MEK (I can tell just by the smell if it's there or not). Also, does Acetone fall into this category? Thanks, Stinger

i do my modeling on the kitchen table,with a window open.i have a young family in the house should i worry with the solvents we use?

Apologies; posted this on another topic ...

Get some liquid cement; Testors or Tenax - or both. I have both on my bench and I found by having those two, I can have 3 glues at hand. Testors dries relatively slow, Tenax relatively fast. You can mix the two 50/50 and get a mid-range glue.

Thanks Gip. I was having a brain fart and forgot the definition of flashpoint. It's been a long time since chemistry class! (for some unknown reason I was thinking spontaneous combustion Shermanfreak will be glad to tell you the reason was old age!! )

Eric

Madda,
Professionally, I'm an industrial hygienist (anticipation, recognition, evaluation and control of potential health hazards in the workplace) and have been managing or otherwise dealing with the effects (toxicological, physical hazards, etc.) of hazardous chemicals since about 1983 when I first stepped into the safety and health community. I taught hazardous materials management for almost 5 years. I have a degree in environmental health with an almost-minor in chemistry (I should have taken analytical chemistry when I had the chance), so your dad is well ahead of me!
Gip Winecoff

Gip, you seem to have a pretty good command of chemicals, what do you do for a living? Just curious, my dad is a chemical engineer, and the stuff you post sounds like stuff he would say.

madda

erush,
The 25 degrees F is dead on. What that means is that at 25 degrees, MEK is producing enough vapors at the surface of the liquid that in the presence of some ignition source (spark, flame, static electricity, etc.) it will flash--not necessarily burn. This is in keeping with the definition of flash point: The lowest temperature at which a liquid will produce enough vapors capable of flashing in the presence of some ignition source. To help ease your mind consider that gasoline has a flash point of
-40F. That's what makes starting your (well, maybe not yours, personally) car in Frostbite Falls, MN achievable. On the other hand, I put gas in my car every other week in 95 degree weather with no problems. I would venture that you probably do the same. Keep in mind that vapor concentrations have to be high enough, and an ignition source present for the material to flash. Ignition and burning temperatures are just a little different. Hope this helps.
Gip Winecoff

QUOTE: Originally posted by styrene More likely, MEK will burn readily. Its flashpoint is 25 degrees F.

Gip I'm not trying to be picky either just want to clarify if that "25F" was a typo? Did you mean a higher temp than that? Some folks might be afraid to pull it out of the freezer

Eric

Claymore68,
Good advice!
Gip Winecoff

Styrene,

Thanks for the additional info. There is nothing wrong with using these or other chemicals and the tips are helpful.

Most of the stuff we use on a regular basis can be dangerous but when someone suggests industrial solvents etc. I believe warning is in order. My intent was not to be alarmist but to notify people of the possible dangers of working with these substances, especially in enclosed ares (an open window may not be enough). I have seen MEK send people to the hospital.

If anyone decides to use a new chemical they are not familiar with GET THE MSDS (Material Safety Data Sheet). BE SAFE


BTW Phosgene gas is also a nerve agent and is used as a chemical weapon.

Not to be completely picky.....
Methyl ethyl ketone (MEK) can react explosively to heat, but concentrations in air have to be pretty high (about 1.8%-about 18,000ppm) for that to occur. More likely, MEK will burn readily. Its flashpoint is 25 degrees F. Just like any organic substance, it's important to keep it away from heat or open flame.
Dichloromethane (also known as methylene chloride), when it decomposes (via heat sources), may produce chlorine gas, hydrochloric acid, carbon dioxide/monoxide, or phosgene. This compound doesn't burn, but may reach decomposition temperatures (>120 degrees C/) when involved in fires with other materials. It does, however, evaporate extremely fast, so inhalation of vapors should be minimized. It is a confirmed animal carcinogen (causes cancer) with an unknown relevance to humans. In my experience, this substance should be avoided as a hobby glue.

MEK, on the ohter hand, has a fairly low order of toxicity. It is not suspected as a cancer agent; still, inhalation should be avoided, or at least , minimized since it has a narcotic effect on the central nervous system and may be irritating to the eyes and mucus membranes at elevated levels. Repeated contact has the potential to produce dermatitis (drying, redness, and inflammation of the skin).

Tenax 7

QUOTE: I am very fortunate I can get both Dichloromethane and M.E.K (Methyl Ethyl Ketone) from work, both are good for modelling just avoid contact with skin.

Also keep them away from mucous membranes and heat sources. MEK can react explosivly to heat, but the Dichloromethane might seperate int it's component parts, Methane gas and Chlorine (Mustard) Gas Trichlorodiflouromethane (R-12) does this and we were told NEVER to smoke while servicing air conditioners.

I am very fortunate I can get both Dichloromethane and M.E.K (Methyl Ethyl Ketone) from work, both are good for modelling just avoid contact with skin.

I'm with Styrene; Tamiya liquid cement is my favorite. I use the regular stuff, though, not the thin.
Back in the States I loved the Testors liquid cement in the black plastic bottle with needle applicator.

I use Tenax7R and it works great. It's super thin, and completely dries in 10 seconds or so, just align your parts, and put a drop on the seam. Wonderful stuff.


madda

thanks for the replys.i think i will give microscale a go as i have seen that in my lhs.and it looks like water as noted.

Testor's Liquid Cement is great stuff; thin, easy to apply, and fairly cheap. By far the best I've found is Tamiya liquid cement. I have the extra thin stuff. It runs into cracks and joints like water, and bonds almost instantly. It smells very strong, and the label is in Japanese, so I don't know what ingredients there are. If you are interested, I'll try to e-mail Tamiya America, and request an MSDS.
Gip Winecoff

Most model manufacturers have their own liquid glue... I have used the Humbrol, the Revell with great success, but found a cheaper alternative in the local hobby-train shop. It's called Plastic Weld and it's produced by EMA. When I say produced, I should really say bottled by... The stuff is just Dichloromethane.

When I was a kid, the 'in' thing was to get some Trichloroethylene which worked wonders. Cheap. But highly toxic too...

I use Revell contacta liquid or Microscale's microweld, the later is like water and runs into joints easily. I wouldn't recommend using tube glue it's messy and hard to get it to go where you want without 'strings' of glue going everywere.