I’m having a heck of a time cementing flat panels together (by the thin edge). I’ve given up on doing it with wood panels (laser kit) and am now attempting it on plastic (styrene) panels. I lay them on a flat surface and use CA but the panels stick to the flat surface. The joint is so fragile that it seperates when I attempt to remove the panels from the flat surface.
I’d appreciate any suggestions anyone might have.
I don’t like using CA for styrene. Solvent cements (fast-working like Tenax 7R or slower like Testors or Plastruct Bondene) work well to dissolve the plastic along the edges and form a strong bond. Also, using pieces of plain styrene sheet for support across the joint will help in keeping the adjacent pieces both aligned and more strongly attached.
CA(super Glue) has no ‘shear’ strength. You have a chance with wood as the glue will get into the grain and make a good connection. Plastic parts need polystyrene glue(like the Testors liquid) that will attack the plastic and ‘melt’ it together. Tennex and Plastic Weld are also good choices.
I suspect you had a problem with the laser kit wood as it is very fine grained, and the edges were ‘seared’ by the laser cutting process.
Jim
If you’re not backing up the joints, try building on a piece of glass, wax paper can also be helpful if you keep gluing to the work surface. I still would back up the joints and use plastic cement,
I agree with Bob. Take a piece of the same material, a quarter-inch or so wide, and put it behind the joint. You don’t even need to glue the two panels together, just glue each of them to this support piece behind them and you’ll be fine.
It also has the advantage of keeping light from leaking through any thin gaps between the panels. When I build a structure kit, I put a square strip of balsa wood in each corner, both for structural strength and to keep my interior lighting from leaking out. In this case, since I’m usually gluing wood to plastic, CA is my preferred adhesive.
As already mentioned, solvent-type cement (I use lacquer thinner) is the best choice for styrene-to-styrene joints. Splice plates are useful for butt joints, but you can also build such assemblies on full-size backing sheets of styrene, which will add rigidity.
Working on glass or waxed paper is a good way to prevent most adhesives from bonding the work to the work surface.
The best bond for most dissimilar materials often depends on the nature of the mating surfaces. Where parts of dissimilar materials fit together (one part into another or one surface nesting inside another) ca or epoxy will provide a strong bond, whereas contact cement is a better choice for joining flat material to other flat material.
Wayne
Another thing that can help you is a splice clamp. I just took this picture quickly to show. This isn’t a part being glued at the moment. It’s just to show you an example. If I where doing this for real I would put a piece of styrene behind the joint to make it stronger.
I hate to see a good topic get pushed down and soon forgotten. Here is my problem. Here is my question. I am in the process of building an N scale model. For fun, I am painting the building with spray paint. A fun project for me to add multiple colors to a building masking off certain areas.
The Spray paint I used was KRYLON Fusion, For PLASTIC its says on the can.
The No-prep, superbond paint. “For plastic, wood, metal, wicker and more”~
“Dries in 15 minutes or less”
I guess no worries about this stuff pealing off.
Here’s a pic.
Here is my problem.
So I place a small amount of CA on the two pieces. Off hand I can’t remember if it was thin or gel. It doesn’t matter I really didn’t think it would hold anyways. I pick up the two pieces later on in the day and ‘Blink’ they break.
Hmm, no residue, I must have used the thin CA. Now I am a newbie and I think I’m in the right place here.
What the heck should I do?
I’m at the point where I am seriously thinking of spraying both halves with Krylon as a way of acting as cement. Or should I say Krypton Spray paint? It does say on the can “superbond paint” because it bonds to just about anything. How about : Does it bond to itself? Can I use the paint as a glue? "Dries in 15 minutes or
Using paint as glue isn’t a solution - it won’t hold. You are trying to make a butt joint and you need a splice plate behind the joint for strength. Is your plastic material styrene? The best glue for this type of joint would be one of the “welding” solvent types as mentioned in the posts above. I would cement the plate to one piece and after it dries cement the other and the joint.
Joe
In all my modeling (or full-sized building for that matter) over the years, I have never found a situation where adhesive of any type will hold one thin edge to another one. The basic problem is that adhesives in general have amazing strength to on-axis pulling (as in, trying to pull the glued panels to the right and left), but are horrible when it comes to lateral (shear) or torquing forces – like when you’re trying to lift those glued panels.
The solution – as a couple of people have noted above, is to use some form of a strong back or reinforcement BEHIND the joint, crossing the seam and being glued to both sides. This means that any shearing force or torque applied to the joint is still an on-axis force to the reinforcement, so your joint holds.
The type of adhesive used is much less important than the manner of its use.
The golden rule is to only glue large, flat surfaces together. If what you’re trying to glue doesn’t have them, figure out a way to make some.
I thank you both for your replies. I have a better understanding of the steps to take, as well as the Philosophy behind it all. I think the only thing that was not mentioned is perhaps to do a test on extra parts to get the feel of the glue and see how well things bond. As it is now, I just managed to find my bottle of Plastruct Plastic Weld. I’m so glad I had bought a bottle of it way back when. Figured it might come in handy.
Thanks again Keith
If in this situation, there are just too many windows/ openings to use a sufficient sized strip of styrene to back up the joint, use clear styrene instead. Precut and dry fit the clear reinforcement, place/ glue to one side, lay the second piece and hold or weight down. A hint to gluing clear is to apply thin cement w/ a small paintbrush. Allow the cement to be “wicked” into the joint while using care not to allow glue to run out into window opening. You may need to concentrate on the joint itself for initial setting, once dried, flip the piece over and carefully place the cement @ various points avoiding marring or running glue into the window openings.
I am personally enjoying this thread to no end. I’m glad I brought this model as an example.(see above pic)
Yeah, Newbie here. I find myself going right back to Modeling 101 with sanding parts with squaring off and the likes. Sanding the joint pieces and the ‘backing’ are so basic but probably the most important thing before you apply the Plastruct glue. The Plastruct glue seemed fine. A bit ‘over-night’ glue but fine and strong.
Now we all have our favorite glue for various reasons and applications. I have mine and to me very little is said on this glue. MICRO KRISTAL KLEAR. Goes on white, sets fast and dries clear, with various other applications including making window panes. On most sanded parts, when dry has great strength. Wipes up with water too.
Anyone care to comment on MICRO KRISTAL KLEAR or comment on their Best All-around Glue?
I’m the one who wrote the original post / question here. Thanks to everyone who replied. I used all the suggestions. I took my two panels and placed them on waxed paper on glass (for a perfectly flat surface), cemented them with Testors, then placed a piece of styrene over the joint for backing and cemented it in place with Tennex. It works fantastic! And I will reinforce my corners with wood or styrene.
Now, does anyone have suggestions for gluing thin pieces of wood (as in a laser kit)? I have my first (and last if I can’t solve this) laser kit which required attaching a piece 1/4" by 10" to multiple pieces about 1/2" by 2". Needless to say, it gave me fits before I gave up.
Thanks again to all who repied (and to those who added additional questions),
Glen
Glen, let me just say Thank You for posting this thread. I too am confronted with gluing two end pieces of styrene end to end. Not by choice but by necessity. Now, I certainly have a game plan on what I need to do. Thank you~
I model in N scale and have built plenty of wooden models. Krystal Klear is by far my number one choice for holding power, goes on white, dries clear with a relative quick drying time. Wipes up with water.
Keith