more glue questions/Barge cement


Bud Rindfleisch
 

Todd,
    Can the Barge be used other than as a contact cement? How about set time if used that way?
     Thanks,
      Bud Rindfleisch


Todd Sullivan
 

Bud,

If you apply Barge to the two surfaces to be joined, let it dry, then press the two parts together, the joint will be very strong, but you have to get placement of the parts aligned correctly the first time, there's no second chance. 

I have also applied Barge and then pressed the parts together.  It takes maybe 20 minutes for the joint to become strong.  I do this when assembling resin carbodies together, as I want some time to be able to align things properly, such as a roof on a body.  I used the Barge sparingly, then go back and apply CA along the joint once the parts are correctly lined up.

Todd Sullivan


Tim O'Connor
 

All volatile contact cements including Goo --

apply to both parts. allow to dry to the touch (almost no tackiness). press together with force.
after a minute or so, forcible separation will result in destruction of the item. if the glued area is
small, you can 'unglue' (within a very short time period) by application of MEK with a brush

I learned about this from Jack Spencer who used contact cement to attach his sill steps which he
fabricated from MYLAR sheet!  (thin, strong, flexible). He also made Mylar overlays for some
offset hopper cars he did, because the material could hold rivet impressions, is as thin as paper,
and could be glued with contact cement.

Tim O'Connor

On 10/9/2021 9:37 AM, Bud Rindfleisch wrote:
Todd,
    Can the Barge be used other than as a contact cement? How about set time if used that way?
     Thanks,
      Bud Rindfleisch
--
*Tim O'Connor*
*Sterling, Massachusetts*


Tim O'Connor
 

Todd

It can be done but it's not recommended! Undried contact cement can attack the underlying material and
lead to joint failure or worse. People who fail to read the instructions for Goo often complain of the problems
they have with it.  😂

Hobby size corner brackets can hold items at a perfect 90 degree angle while the adhesive sets. I also use
small machinist squares (Micromark I think) for a quick 90 degree setup with CA.

On 10/9/2021 10:42 AM, Todd Sullivan via groups.io wrote:
Bud,

If you apply Barge to the two surfaces to be joined, let it dry, then press the two parts together, the joint will be very strong, but you have to get placement of the parts aligned correctly the first time, there's no second chance.

I have also applied Barge and then pressed the parts together.  It takes maybe 20 minutes for the joint to become strong.  I do this when assembling resin carbodies together, as I want some time to be able to align things properly, such as a roof on a body.  I used the Barge sparingly, then go back and apply CA along the joint once the parts are correctly lined up.

Todd Sullivan
--
*Tim O'Connor*
*Sterling, Massachusetts*


Robert kirkham
 

It would be good to see a clinic on using mylar in these ways - (and, incidentally, on what forms and where to purchase it from.)

Rob

On Oct 9, 2021, at 7:42 AM, Tim O'Connor <timboconnor@comcast.net> wrote:


All volatile contact cements including Goo --

apply to both parts. allow to dry to the touch (almost no tackiness). press together with force.
after a minute or so, forcible separation will result in destruction of the item. if the glued area is
small, you can 'unglue' (within a very short time period) by application of MEK with a brush

I learned about this from Jack Spencer who used contact cement to attach his sill steps which he
fabricated from MYLAR sheet! (thin, strong, flexible). He also made Mylar overlays for some
offset hopper cars he did, because the material could hold rivet impressions, is as thin as paper,
and could be glued with contact cement.

Tim O'Connor

On 10/9/2021 9:37 AM, Bud Rindfleisch wrote:
Todd,
Can the Barge be used other than as a contact cement? How about set time if used that way?
Thanks,
Bud Rindfleisch


--
*Tim O'Connor*
*Sterling, Massachusetts*


np328
 

    Tim's comments on post 187715 in the second sentence are well founded.  I recall in experiences from an earlier club layout, a member who assembled out of Design Preservation Miniatures modular parts, a skyscraper  perhaps 10 stories high. He assembled it with Goo and for a few weeks it stood upright and square. Then after a while it developed a slight lean. Another member put his hands around it and set it straight again, only for the structure to lean again next week now in a different direction. 
     Strange thing was, there was no joint failure. The structure held together, even when one member jokingly gave it a lateral twist!   
Where the DPM panels were joined, the plastic became quite malleable in that if you would press a screwdriver point or even a fingernail into the plastic, it did not take much pressure to leave a lasting impression. I am not a chemist and can't say if it attacks other plastics (or resin) in a like manner however of the DPM material, it seemed to absorb the volatiles quite easily. I don't think the Goo ever completely set.                                                                                                                                           James Dick - Roseville, MN 


Todd Sullivan
 

Hi Tim,

Hmmm.  I appreciate your warning, but I have not had any problems with this.  Perhaps I've been lucky.  I do use quite small amounts of contact cement, usually when gluing roofs to body sides and ends.  Just enough contact cement to hold the roof on and in place until I can get the CA wicked into the seams. 

Todd Sullivan.


Scott H. Haycock
 

Most contact adhesives are solvent-based. I wouldn't use them on plastic models. You can buy water-based contact adhesives in cans, but I've not seen any in tubes, like Barge Cement.

Scott Haycock
Modeling Tarheel country in the Land of Enchantm
ent

On 10/09/2021 3:53 PM Todd Sullivan via groups.io <sullivant41@...> wrote:
 
 
Hi Tim,

Hmmm.  I appreciate your warning, but I have not had any problems with this.  Perhaps I've been lucky.  I do use quite small amounts of contact cement, usually when gluing roofs to body sides and ends.  Just enough contact cement to hold the roof on and in place until I can get the CA wicked into the seams. 

Todd Sullivan.


Andy Carlson
 

In an unconfined situation, the solvented joints used with our modeling glues will dissipate into the open air. Problems arrive when the solvents are trapped and have nowhere to out gas, so they get absorbed into the the surrounding plastic. This is where a lot of damage can occur if not resolved correctly. The contact cements, which are tacking off before contact joining the two halves, are out gassing through this "tacking' procedure, thus allowing less trapped behind solvents. This I believe why contact cements work as well as they do for joining plastics together, having less solvent at the time of joining. In actuality, most solvent welded plastic joints need much less solvent then we often apply (If some is good, more is better). I remember having fits getting 0.005" styrene pieces to laminate to a larger styrene surface. The edges scalloped like crazy, and surface waves replaced the formerly planar flat fields. I cured this problem by performaning a similar flashing-off as what is recommended for contact cement; the degassed joining areas looked like there wasn't any further remaining solvent, but the thin styrene sheet bonded quite well with no distortions with what little solvent remaining being quite adequate.
-Andy Carlson
Ojai CA

On Saturday, October 9, 2021, 02:58:34 PM PDT, Scott H. Haycock <shhaycock@...> wrote:


Most contact adhesives are solvent-based. I wouldn't use them on plastic models. You can buy water-based contact adhesives in cans, but I've not seen any in tubes, like Barge Cement.

Scott Haycock
Modeling Tarheel country in the Land of Enchantm
ent

On 10/09/2021 3:53 PM Todd Sullivan via groups.io <sullivant41@...> wrote:
 
 
Hi Tim,

Hmmm.  I appreciate your warning, but I have not had any problems with this.  Perhaps I've been lucky.  I do use quite small amounts of contact cement, usually when gluing roofs to body sides and ends.  Just enough contact cement to hold the roof on and in place until I can get the CA wicked into the seams. 

Todd Sullivan.



_._,_._,_


Daniel A. Mitchell
 

I have had, and seen, numerous examples similar to your observation. The “Goo” definitely attacks many plastics. Oddly, even after the “Goo” has dried, the adjoining plastic remains damaged ... soft, rubbery, weak and often warped. Worse, the damage seems to keep spreading, and soaking deeper into the plastic. I’ve worked on items over 40 years old that were utterly destroyed … the “Goo” just keeps on eating into the plastic. The residual “Goo” being much harder than the damaged plastic around it. this cannot be just solvent penetration, but some form of chemical reaction.

Anyway, do NOT use “Goo” on plastic items. It’s fine on metal and wood, but NOT plastic!

Dan Mitchell
==========

On Oct 9, 2021, at 5:24 PM, np328 <jcdworkingonthenp@...> wrote:

    Tim's comments on post 187715 in the second sentence are well founded.  I recall in experiences from an earlier club layout, a member who assembled out of Design Preservation Miniatures modular parts, a skyscraper  perhaps 10 stories high. He assembled it with Goo and for a few weeks it stood upright and square. Then after a while it developed a slight lean. Another member put his hands around it and set it straight again, only for the structure to lean again next week now in a different direction. 
     Strange thing was, there was no joint failure. The structure held together, even when one member jokingly gave it a lateral twist!   
Where the DPM panels were joined, the plastic became quite malleable in that if you would press a screwdriver point or even a fingernail into the plastic, it did not take much pressure to leave a lasting impression. I am not a chemist and can't say if it attacks other plastics (or resin) in a like manner however of the DPM material, it seemed to absorb the volatiles quite easily. I don't think the Goo ever completely set.                                                                                                                                           James Dick - Roseville, MN 


Tim O'Connor
 


regardless of carrier (water or other solvent) what makes contact cement work is that the
adhesive remains after the carrier has evaporated. Todd has not had problems because the
cement doesn't attack or absorb into urethane resin... but that does not mean it has set up
permanently or well. But since it's just for temporary use and CA is applied afterwards, it
hasn't lead to any failures. I'm the opposite - I use CA for temporary bonds, and then apply
2-part epoxy or other flexible permanent adhesive (canopy glue, or silicone caulk)

Tim O'Connor
 

On 10/9/2021 5:58 PM, Scott H. Haycock wrote:
Most contact adhesives are solvent-based. I wouldn't use them on plastic models. You can buy water-based contact adhesives in cans, but I've not seen any in tubes, like Barge Cement.

Scott Haycock
Modeling Tarheel country in the Land of Enchantm
ent

On 10/09/2021 3:53 PM Todd Sullivan via groups.io <sullivant41@...> wrote:
 
 
Hi Tim,

Hmmm.  I appreciate your warning, but I have not had any problems with this.  Perhaps I've been lucky.  I do use quite small amounts of contact cement, usually when gluing roofs to body sides and ends.  Just enough contact cement to hold the roof on and in place until I can get the CA wicked into the seams. 

Todd Sullivan.


--
Tim O'Connor
Sterling, Massachusetts


Todd Sullivan
 

Thank you, Tim, for adding more insight to this conversation.

Todd Sullivan


np328
 

Todd,
      I would like to think that you, and others are safe in the manner you described using this adhesive. (post 187724) 
And I put out my post only as a heads up to prevent the experiences that Andy and Dan experienced.
Too often we have read here where a model is painstakingly made only to have some one step suddenly turn ugly.   
And acknowledging Andy's comment about the the good old American POV that "if some is good, more is better", does not always apply.   
                                                                                                                                                                                                                              James Dick    Roseville, MN