LEGO glue or sealant
snogards99
help with. The project involves building a large LEGO sculpture
requiring assembly with "glue" as it has to be on semi-permanent public
display and will be manhandled by kids. After 6 months of display, we
would like to recover the 50,000 LEGO pieces, so I am seeking a glue
that has the following requirements:
- Glue, adhesive, sealant or finish that holds bricks together
solid.
- does not eat ABS plastic (aka LEGO)
- clear and transparent so it does not effect aesthetics, should
dry to the same gloss of the original bricks
- water soluble (pieces can be soaked in hot water, possibly
requiring an agent also that is safe and environ friendly but ideally
just water) that completely recovers the bricks and does effect the
original finish.
- a non-instant 'open' dry time (say, 12-24 hours) to allow for
correction of mistakes
- Sprayable since idealy it would hold on the outside so I don't
have to reassemble glued -or- easy to apply (a glue stick or
multiple-use tube or dispenser) and work with (does not bond to
fingers, easy clean-up).
- relatively inexpensive (not Elmer's but not industrially
expensive)
- few fumes during use and none after drying
Does such a glue exist?
I have experimented with several glues and am currently using
watered-down Elmer's Washable glue sprayed in a light coating. It has
many of the above characteristics but the finish is slightly dull and
it's so watery that I cannot spray to an even coat (it drips and then
pools at the edges giving a uneven, bumpy look).
Thank you for your help!
snogards
Eli the Bearded
> I have a large LEGO project for school that I am hoping someone can
> help with. The project involves building a large LEGO sculpture
> requiring assembly with "glue" as it has to be on semi-permanent public
> display and will be manhandled by kids. After 6 months of display, we
> would like to recover the 50,000 LEGO pieces, so I am seeking a glue
> that has the following requirements:
An interesting problem. While the group choice (rec.toys.lego) reflects
your application, I can't help but wonder if there might be a more
fruitful location to ask this question.
> - Glue, adhesive, sealant or finish that holds bricks together
> solid.
> - does not eat ABS plastic (aka LEGO)
The usual answer to the first requirement is in direct conflict with
the second. Oatey brand plumbing adhesive, sold to glue bits of PVC
pipe together, bonds many other plastics very well. I keep a jar around
for repairing kids toys. I don't let the kids play with them for a day
or so after gluing, as the fumes are nasty. It works by melting the
plastic together, which is a bit of an overlap with "eat[ing] ABS".
> - clear and transparent so it does not effect aesthetics, should
> dry to the same gloss of the original bricks
> - water soluble (pieces can be soaked in hot water, possibly
> requiring an agent also that is safe and environ friendly but ideally
> just water) that completely recovers the bricks and does effect the
> original finish.
> - a non-instant 'open' dry time (say, 12-24 hours) to allow for
> correction of mistakes
> - Sprayable since idealy it would hold on the outside so I don't
> have to reassemble glued -or- easy to apply (a glue stick or
> multiple-use tube or dispenser) and work with (does not bond to
> fingers, easy clean-up).
> - relatively inexpensive (not Elmer's but not industrially
> expensive)
> - few fumes during use and none after drying
>
> Does such a glue exist?
Let's look at the requirements: clear, glossy, water soluble, slow dry,
cheap, low fumes. All of those could be met by simple syrup (ie sugar
and water or corn syrup and water). That wouldn't be a strong glue,
and long term it would probably collect dust on exposed areas, but it
might do the trick for you.
I don't quite understand what you are asking for in the bullet point
begining "sprayable...". Are you asking for something to coat the outside
of the bricks to hold them together post assembly? That's not really a
job for glue...
Elijah
------
simple syrup is sprayable, but might clog a sprayer
snogards99
Eli the Bearded wrote:
> Let's look at the requirements: clear, glossy, water soluble, slow dry,
> cheap, low fumes. All of those could be met by simple syrup (ie sugar
> and water or corn syrup and water). That wouldn't be a strong glue,
> and long term it would probably collect dust on exposed areas, but it
> might do the trick for you.
>
> I don't quite understand what you are asking for in the bullet point
> begining "sprayable...". Are you asking for something to coat the outside
> of the bricks to hold them together post assembly? That's not really a
> job for glue...
>
> Elijah
> ------
> simple syrup is sprayable, but might clog a sprayer
Thank you for the response.
After MUCH experimentation (I've tried spraying and reg. glueing
Elmer's Washable Glue AND Gel, Elmer's Glue All, and Aleene's Tacky
Glue) I've basically come to the conclusion that it's not possible to
glue the outside. Yes, I was hoping to find a clear coating that would
both hold the model and save time reassembling.
These glue's work well (the best is Aleene's Tacky) and result in a
nice coating if brushed on and a 'medium' hold. A medium hold being
that a child cannot pull them apart, but an adult can, it takes some
force. The result is a clear coating (no cloudiness) that comes off
easily when soaked in a bath tub of warm water. It's almost completely
smooth and not noticable with the same gloss as the original bricks,
when brushed properly.
An interesting note is that applying the glue on the outside actually
results in these glues working into the seams between the bricks
somewhat. It's not a perfect seal
When it comes to spraying these glues however they need to be watered
down so much (like a milk consistancy) that the result is a runny mess
on the non-pourous, slick bricks. The glue just runs off and pools at
the corners. When it dries it's uneven and bumpy. So much for the
'dream' of spraying something on this. I must have been crazy to think
that will work.
At this point, I think it is unavoidable to glue each brick in place to
maintain the original finish... adding alot more work to the projects.
That said, I am experimenting with Elmer's Washable Glue versus
Aleene's Tacky Glue, glueing a test model together and waiting an
entire week (despite the instructions, the actual full cure time for
these is a week as with most PVA glue, because of the semi-seal the
bricks make and the air pocket inside it takes much longer for these to
dry).
I will then do some strength tests. I think the result will be a
strong-to-medium hold (stronger than just sprayed) that can be broken
by 'adult' hands if needed at the week points. The model is so large
it will not fit in a bathtub without breaking into chunks.
The final test will be then to soak the brick chunks in a tub to see if
water can get into the seams such that it will fall-apart and the glue
will desolve completely, recovering the bricks easily.
Note that Elmer's Washable has GREAT reversabilty but has a POOR hold
on plastics. Aleene's is GOOD solubility but has GOOD hold.
I hope I'm not rambling and some day this post'll help someone. I'll
follow-up with the best option I find.
Thanks!
Christopher Witmer
Thanks for the write up. Exactly what I wanted to know. My son has a Lego set
he wants to us as more of a toy and I want to help him get there. Thanks
again!
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