Gluing Korber Walls

Korber is a forum sponsor and Rich will post here. Just send him an email and he will help you. Plus I believe there have been prior posts on this topic.

Don:

Thanks - I did a simple search and found one thread from 2012 which had good things to say about gorilla glue. As mentioned above this is the glue Rich recommends. The thread also had a good comment by Alan Graziano about using hot glue after the gorilla glue cures. I was hoping there would be some more recent info.

Joe

Joe,

Thanks for sharing your findings. I was just getting ready to assembly a large structure and was wonder what material the panels where made out of and and what glue would be appropriate.

Older Korber kits used a different type of resin and had lots of issues of loss of adhesion of glues, as well as warping. I believe Rich has upgraded the new production. He'll chine in soon.

Good information. What about that glue they have been advertising on TV. You put it on and then cure it with a ultraviolet light as the Dentists use. Watching the commercial I don't think it would work on the outside but hidden inside maybe that would be a choice for adding strength. That is if it really does what it says...................Paul

I am building the Jaybar Corp. Kit #902, by Kober Models. On the back side of the directions, it states optional Hot Glue. That may hold the corners, but it may not look good. Looks like I will be doing a flat structure. If I had the real-estate I would like to do the roundhouse. 

Gary - Cheers from The Detroit and Mackinac Railway

Will be interesting to see if Rich has any gnu-glue comments...

I'm currently building/assembling Korber kit #969, General Light & Power Office.  I purchased this at the last York meet from Rich.  His instructions sayeth:

"Cyanoacrylate (CA) glue.  Also known as Super Glue, Gorrilla(tm) super glue works well.  We really like the new Gorilla brand super glue because it is thicker than most super glues, and allows you to put it on a seam while holding the part in your hand, and will not run when you turn the seam on the side to put two pieces together.  This glue is available in most retailers, including the larger home improvement stores."

The next bullet under "Materials Needed" list suggests the use of a CA glue accelerator (optional)

So, that's what I've been using...with square wood strips for reinforcement of all seams and floor/roof supports.  Nary a problem.

But, then, I haven't given the buildings the UPS/FedEx rugby scrum test, either.

The Korber building walls are a pourable resin, probably two-part, like most of this product genre.  I would never have expected a glue like Plastruct's Plastic Weld to have any success.  Nor Tenax 7r.  This resin, when cured, is not 'weldable' as with styrene, ABS, polycarbonate, et al. 

Roughing the bonding surface with sandpaper is a good idea, though.  It doesn't take much.

That said, I can relate to the shipping of buildings only to have them arrive in pieces.  Wife has been disposing of a large HO estate for a client.  LOTS of Walthers Cornerstone, Atlas, Faller, Kibri, et al kits were assembled for the layout.  Unfortunately, the deceased builder apparently never expected his buildings to do anything more than just sit in one spot on the layout.....well, duh!!  Ergo, he was very 'thrifty' with the use of cement in ALL of his seams and details of the buildings.  Needless to say, they haven't all fared well in shipping, but prospective buyers have been forewarned in the auction descriptions...and the buildings have been first placed in a large plastic bag before final packing for shipping to capture any parts coming loose. 

FWIW, always...

KD

The Classic Korber Kits are made out of resin. Liquid plastic cement and MEK will not dissolve resin. I recommend using either Epoxy or CA.

I suspect your problem with the Gorilla epoxy is that perhaps either the instructions were not followed to the letter i.e. thoroughly mix equal amounts and apply within 5 minutes and then wait a full 24 hours to cure, or the walls were not washed to remove any residual mold release compound. 

The problem with CA is that it has no shear strength. By applying a lateral force you can easily break the bond.

I've put together old Korber kits using J B Weld epoxy without any problems whatsoever. 

Gorilla CA claims that there is some rubber-like material in the mix to impart some impact resistance. That's CA's biggest drawback: it dries brittle. The UV cure would work UNLESS the shape of the joint blocks the UV from penetrating the joint. That's why it's shown primarily as a surface adhesive or filler. UV must hit all of the resin. Talk to your dentist. They're using light-cured resins all the time. 

When we took on the line, I tried the glue I had gravitated to for my own model building, the Gorilla Super Glue (Lite blue cap).  By coincidence they are based here in Cincinnati.

The glue as Trainman mentioned has a bit of give to it with the "rubber" material they include in the glue.  I use a CA accelerator to speed up the process once I get the part in place, but the glue set quickly with out it.

I also use this process on some of the injection molded polystyrene kits we have, and on some laser cut kits with similar results.

The walls today are a two part resin, and as you note the color is molded in to the compound with a tint.  Previously they had been made of a off white resin and painted.  This is the material for the classic Korber kits.  Many of the newer ones are laser cut, and the newest lines are plastic injection molded parts.

If i remember correctly i think Korber recommends model air plane cement.

I did some research on Gorilla Glue CA. It sounds like the company adds or bases the glue on urethane to give it its impact resistance. 

I have a bottle of Liquid Fusion polyurethane glue I use primarily for PVC pipes. I will give this a try today.

The Liquid Fusion separated with moderate hand pressure however since it is a urethane glue I am going to take a page from Alan Graziano's book and use it in place of the hot glue he recommends i.e I will use Gorilla Glue or Mike's Model Crafters for the walls and wood supports then run a bead of Liquid Fusion on the inside for added impact resistance.

Sounds crazy, but I have used CA glue and mixed it with Elmers wood glue, than apply to the joint, clamp for 2 minutes and it is solid as a rock....

Joe,

I glue with CA and then cap with a glue gun. I do not know what they call glue sticks other than glue sticks. CA cannot take any shock. If you drop something it can easily break. I have had great success using the two different glues.

J Daddy,

When you mix CA with Elmers, The Elmers glue acts as  an accelerator to make the CA harden quicker. I knew another modeler that used this method all the time and it worked well for him.

Alan Graziano

What is the mix ratio of CA to white glue? I will give it a try.

"The problem with CA is that it has no shear strength. By applying a lateral force you can easily break the bond."

"CA cannot take any shock. If you drop something it can easily break. "

Not advocating the use of CA necessarily, but just wondering what you guys are doing to your models that introduces such impact into them that you have to account for this...bouncing them off the floor, etc. 

Maybe buying a basketball would be good?

Maybe not dropping stuff would be a good practice to embrace? 

Korber Models posted:

When we took on the line, I tried the glue I had gravitated to for my own model building, the Gorilla Super Glue (Lite blue cap).  By coincidence they are based here in Cincinnati.

The glue as Trainman mentioned has a bit of give to it with the "rubber" material they include in the glue.  I use a CA accelerator to speed up the process once I get the part in place, but the glue set quickly with out it.

I also use this process on some of the injection molded polystyrene kits we have, and on some laser cut kits with similar results.

The walls today are a two part resin, and as you note the color is molded in to the compound with a tint.  Previously they had been made of a off white resin and painted.  This is the material for the classic Korber kits.  Many of the newer ones are laser cut, and the newest lines are plastic injection molded parts.

 

Since Rich told me about Gorilla super glue, I have used it on everything. My scratch built G scale engines were falling apart while being constructed using regular superglue, or the even the industrial glue that was recommended. I was advised to put hot melt on the inside of the shell to help with that. You can't do that on the fine details. With the gorilla glue, that problem went away.

I really want to thank Rich from Korber Models again for helping me make solid builds. I have run these engines outside and don't worry about things falling off anymore.

MWB:

I use the drop test sparingly and only to test joints mostly to simulate shippers bouncing boxes around. I always try to pack  to survive shipping but no packing is foolproof. Being a 'garage' business I have seen shippers pull up to the driveway to make deliveries and then on more than one occasion saw how they set up for the next delivery. The driver would disappear into the back of the van. Then I would see boxes being tossed up front hit the windshield and land on the dashboard. Shipping companies don't matter and fragile stickers don't have much influence.

Joe

Martin,

 I only mentioned CA not having any shear strength as something to be aware of when using it. I have no problem with any of my CA joints separating.

The Gorilla CA glue with blue top is the only CA glue I have had consistent success with, although I have not yet used it on a Korber kit. I have not tried using any accelerator with it. The Elmers & CA mix sounds interesting as does adding hot glue to the joints.

I have also had good luck with Testors Model Master Liquid Cement for Plastic Models (#8872C on package) on a couple of Ameri-Towne kits. I have not tried the drop test or shipped any of these items, but they did survive without damage after we moved a couple of years ago.

DennisB posted:

Martin,

 I only mentioned CA not having any shear strength as something to be aware of when using it. I have no problem with any of my CA joints separating.

I've not had any joints in models fail as yet myself, although I tend to use a mix of Goo and CA for troublesome materials and joints. 

I rarely ship structures, and don't do much custom work for others anymore (generally a PITA activity...) but I have shipped a pretty substantial number of scratchbuilt cars and all and have also yet to have anything fail in route due to shipping.  Then again, I grossly over-engineer the packing to point that one recipient complained about the amount of time it tool to unpack an engine.......

OTOH, I'm not altogether sure about joints in myself however having spent the last 2 months in a wrist brace / splint.....and maybe more to go.

So, as I said in my earlier response, simulating abusive treatment of my structures is not part of my model-building 'QS9000' process.  If and when they're to be shipped to der hinterlands, I'll be so much moldy refuse in a box......not my problem.  And we don't have much use for the Richter scale in Michigan.

OTOH, this summer I believe we (wife & I) will be doing more in creating a garden railroad in G (#!) scale.  In this case, frequent movement of the several structures....either for seasonal storage or as victims of a 2-Golden romp...will be more than likely a periodic occurrence.  So I'm always on the hunt for better tools.  I'll have to try the CA + Elmers, and/or CA + Goo on some of the garden structures. 

Good tips!

KD

dkdkrd posted:

And we don't have much use for the Richter scale in Michigan.

Wait for it.........we had another earthquake in VA just in the past couple of weeks.

OTOH, this summer I believe we (wife & I) will be doing more in creating a garden railroad in G (#!) scale.  In this case, frequent movement of the several structures....either for seasonal storage or as victims of a 2-Golden romp...will be more than likely a periodic occurrence.  So I'm always on the hunt for better tools.  I'll have to try the CA + Elmers, and/or CA + Goo on some of the garden structures. 

Good tips!

KD

I'd look into adhesives and materials used for maritime applications for outdoor models.