Glues

July 5, 2021

So I thought it would be interesting to just have a topic to discuss glues, what folks use for what. Godzilla knows I have played with many glues over the years and still folks pop up with new ones all the time! We have had this discussion about many glues all over the place, figure this may be the best place to have a focused discussion. This came up today on the n-scale list to create a resource of what works on what well, application, stability, strength, cleanup etc. I’ll try to pull out folks descriptions and comments into a list here in the first thread. If folks can give maybe the following data points on a glue along with what it works best in maybe we can make a nice reference for everyone. Just copy the list below and fill in your experience. With discussion we can try to get a good general reference then. Maybe we can compile them into a spreadsheet.

cheers

jeff

Name/company

General Description

Works on: what material and/or surface does it bond well to

Doesn’t work on: what materials and/or surfaces doesn’t it bond well to

Drying time: seconds, days

Strength: how good does it hold

Flexibility: is the bond at all flexible when dry

Color when dry: what color is the glue when dry

How It Works: how does the glue work chemically

Application: how to best apply it or tricks and tips.

Waterproof: can the cured glue stay set if exposed to water

Dilute: can it be diluted for use and what to dilute it with

Cleanup: can you clean off excess easily and is solvent needed

Stability: how long/well does the glue last in container after opening

Best used on: what materials/things is this your go to

Warnings: what to watch out for, hazards, toxicity, etc.

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Cyanoacrylate, CA, or Super Glues (many many companies)

CA glues are great for rapid bonding to a variety of surface with pretty strong bonds. It can dry in second to minutes and curing is accelerated by moisture (why it goes off very fast once in your skin). You can get it in varying thicknesses from very runny to very thick gels. Other Accelerators can make it cure almost instantly and if added to a fillet of baking soda it can create a very rapidly curing sort of mortar to reinforce corners on joints (but this does creat a bit of heat). It crazes/fogs clear plastics like styrenes and acetates.

Works on: Most all materials

Doesn’t work on: Slick, softer plastics like polyethylene, polypropylene, derilin, some vinyls. Thin ca glues do not work well on very porous surfaces like papers and wood, but thicker ca glues can, but joints with larger gaps even thicker ca glue does not tend to cure well and is brittle in big chunks of just dried glue in joints. Never use near clear styrene or clear acetate as even off gassing of ca glue will fog them. Glueing parts near clear plastics can cause crazing of the clear bits fast.

Drying time: Without accelerators usually less than a minute in normal humidity. Dryer humidity can take longer to set (fogging your breath on the joint can help). There are many accelerators to make bonding almost instantaneous. Baking soda can be used as an accelerant and solid medium. New 2 part ca glues of an accelerator and glue have come out for bonding more porous woods together quickly

Strength: Very strong in larger flat joints. More brittle on edge and butt joints. Making filets along corners of joints with baking soda infused with ca glue can make super strong joint supports. There are some CA glues that have additives for better shear strength.

Flexibility: Not flexible, pretty brittle once fully cured. Some of the thick forms are not quite as brittle when fully cured. Some CA glues have rubbers added to reduce the brittleness of the polymerized CA glue.

Color when dry: Clear to hazy white

How It Works: CA glue hardens when the monomers of cyanoacrylate esters polymerize which is usually catalyzed by water.

Application: Small amounts of ca glue can be delivered with the eye end of a sewing needle (eye acts as a reservoir for a small drop of glue) or with etched metal “glue looper” applicators (http://www.creativedynamicllc.com/the-glue-looper.html). Tiny tube nozzle hoses can be added to bottle to deliver small amounts. These can be made by drawing out small plastic tubes in plastic Q-tips with some heat (https://youtu.be/nkHm66qBG7c) or inexpensively bought in bulk. Toothpicks and small dental glue applicators (often times sold as “micro brushes”) work well to spread larger amounts of glue on parts.

Waterproof: Yes

Dilute: Can’t easily dilute CA glues but they usually come in very thick, thick and thin consistencies

Cleanup: Acetone. Once cured acetone can dissolve CA glue, but on many plastics enough acetone to break up the glue joint can also attack plastics and paint around the glue. Glue does not scrape off or carve well with a knife.

Stability: Usually lasts in a tube 6-12 months after opened. Keeping in a sealed bag with a desiccant pellets can help lengthen life of opened bottles/tubes. Higher humidity environments will cause open bottles to go off faster. Long term storage in the freezer can make CA glues last years, but should be allowed to reach room temperature before opening as condensation can form inside the bottle and set off the whole bottle.

Best used on: Small parts that you need to get stuck on fast. Large surface bonds where you need a really good bond. Good to mix and match stuff like metals and plastics. Thin CA glue wicks into already placed joints well (but it can wick everywhere so be sparing!). CA glue can be used as a wood surface stabilizer to seal and finish wood with a clear finish that can the be polished.

Warnings: Keep CA glue out of your eyes as will bond instantly to moist eyeballs! Also fumes are also harmful to the respiratory system so keep good ventilation when using (small 5v computer fan on the work bench blowing away from you can easily clear small amounts of fumes from being breathed in). Bonds to skin very fast as the moisture in your skin cures the CA glue.

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2 Part Epoxy (many brands like JB weld, Locktite, gorilla glue)

2 part epoxies are great glues where a strong bond is needed and it can space fill a bit. Equal amounts of each are put side by side on a scrap piece of cardboard and mixed well quickly with swirling and folding with a small stick or disposable spatula applicator for a minute or so. Once mixed you have a sort time until it begins to set (various brands/types have different set times). Epoxies are usually pretty thick and not easy to apply to tiny joints and can be very sticky and messy. Very hard to wipe off excess cleanly

Works on: most all materials

Doesn’t work on: slick plastics like polyethylene, polystryene, derilin, etc

Drying time: sets few minutes to an hour depending on type (fast 2-5 min, regular 10-15, slow 30-60 min) cures totally usually overnight

Strength: strong bond that can fill gaps

Flexibility: hard once cured not flexible. Glue itself is usually not very brittle

Color when dry: Clear to slight dark tint

How It Works: epoxy resin monomers are polymerized with the addition of a catalyst agent.

Application: usually spreader stick or small disposable applicator

Waterproof: yes

Dilute: can’t usually dilute epoxy, but you can get thinner resin

Cleanup: once cured it’s there… heat gun can lift some but would ruin most modeling materials except metals. Before it sets you can try to wipe or scrape it off but some will remain on the surface and when starting to set it will pull fibers out of paper towels and rags. Before the epoxy fully cures vinegar can be use to clean it off non-porous materials and skin, if that fails acetone works well. Bits of epoxy on clothing can sometimes be softened and picked off by soaking the epoxy area in boiling water for a bit.

Stability: Epoxies in tubes can just die usually ending up with mixed epoxy that never really cures and does not bond well. Best to always test a little bit if you have not used the epoxy in a while before going at your project.

Best used on: where strong joints are needed and where there are potential small gaps in the joint.

Hazards: none (wouldn’t eat it)

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E6000 (Eclectic products)

E6000 is like a thick rubber cement that sticks tighter to most any material but cures a bit flexible (not as flexible as rubber cement). Nice for joints that may need to flex a bit or something you may want to disassemble later as on smoother, non porous surfaces you can pry pars apart and cut thru the slightly soft glue and rub/scrape off old glue.

Works on: most all materials

Doesn’t work on: very slick plastics it will stick but can peak off

Drying time: 5-10 min to set well and overnight to totally cure

Strength: holds well to most any surface and very strong on fabrics

Flexibility: nice and flexible for things that need to have a tad of resilience. Glue joint can be cut easily

Color when dry: Clear To slight dark tint

How It Works: tetrachloroethylene solvent base with dissolved styrene and butadiene polymers. When the solvent evaporates the polymers reform making a sticky joint between the two parts, but not chemically bonding to the surfaces much.

Application: small applicator. Very thick and stringy

Waterproof: yes

Dilute: not dilutable

Cleanup: very sticky. Can take off with acetone or goo gone from smooth surfaces

Stability: goes off in a few months usually in tube after opening so best to get the small tubes not the big ones.

Best used on: anything that may need a bit of flex ina joint, works great in fabrics and holds even slick suface plastics ok. Can peal/scrape a lot of it off many smooth surfaces. Works well on things you may want to disassemble later.

Hazards: contains organic solvents, use in a well ventilated area.

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White/PVA Glue

Basic Elmer’s and many wood glues are water based Polyvinyl Acetate. Good all purpose glue that can be softened and removed with moisture.

Works on: paper, wood, fabric, leather, foam board, and styrofoam. Will stick to plastics but with a little shock it will usually pop loose

Doesn’t work on: does not bond well to metal, glass and plastics. PVA needs pours materials to seep into to form a bond once fully cured. PVA may hold some on smooth materials, but will pop loose with some shock or peel off.

Drying time: Dries fast - few minutes to set up and a hour or so to fully cure.

Strength: Holds well, strong bond.

Flexibility: glue drys hard with a bit of flexibility

Color when dry: Clear, but can yellow with age and prolonged UV exposure

How It Works: As water evaporates or is drawn out into the materials the PVA polymers coalescence into a matrix that infiltrates pores in the two materials being joined and provides a physical connection.

Application: toothpicks, micro applicators, brushes

Waterproof: No water will soften the glue and eventually dissolve it.

Dilute: can be thinned with water

Cleanup: Cleans with water while still wet. Damp cloth works.

Stability: years if bottle kept closed and temperatures not too high or low

Best used on: paper, wood and foamcore. Can hold some plastics but bond is not strong and can be popped loose.

Hazards: none (wouldn’t eat it, but PVA is used as a synthetic gum base in some chewing gums)

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Arleen’s Tacky Glue

A thick and very tacky PVA glue. Good all purpose glue that can be softened and removed with moisture.

Works on: paper, wood, fabric, leather, foam board, and styrofoam. Will stick to plastics but with a little shock it will usually pop loose

Doesn’t work on: does not bond well to metal, glass and plastics. Glue will pop loose with some shock or peal off

Drying time: Dries fast - few minutes to set up and a hour or so to fully cure.

Strength: Holds well, strong bond.

Flexibility: glue drys hard and not much flexibility

Color when dry: Clear, but can yellow with age or prolonged UV exposure

How It Works: As water evaporates or is drawn out into the materials the PVA polymers coalescence into a matrix that infiltrates pores in the two materials being joined and provides a physical connection.

Application: toothpicks, micro applicators

Waterproof: No

Dilute: can be thinned with water

Cleanup: Cleans with water while still wet. Damp cloth works.

Stability: years if bottle kept closed and temperatures not too high or low

Best used on: paper, wood and foamcore. Can hold some plastics but bond is not strong and can be popped loose.

Hazards: none (wouldn’t eat it, but PVA is used as a synthetic gum base in some chewing gums)

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Tamiya Craft Bond

White water based PVA glue. Dries clear. Perfect for dioramas and paper products. Very similar to white glues.

Works on: It is compatible with paper, wood, fabric, leather, foam board, and styrofoam.

Doesn’t work on: bonds to most materials that I have tried but best for paper, foam core, polybak (laser board)

Drying time: Dries fast - a minute or two.

Strength: Holds well, strong bond.

Flexibility: Compared to standard wood glues, this craft bond dries into a softer consistency to help provide shock protection.

Color when dry: Clear, but can yellow with age or prolonged exposure to UV

How It Works: As water evaporates or is drawn out into the materials the PVA polymers coalescence into a matrix that infiltrates pores in the two materials being joined and provides a physical connection.

Application: Glue bottle has a fine tip. Great for accurate application.

Waterproof: No

Dilute: it’s a PVA glue and can be thinned with water

Cleanup: Cleans with water while still wet. Damp cloth works.

Stability: a few months is the longest I've let one sit.

Best used on: Paper structures is what I use it for the most. Like Sankei buildings. Also, it does not transfer excessive water to paper, so the joints remain wrinkle-free. Looks like a white PVA glue but dries very fast and achieves a very strong (transparent of course) bond. Good for clear parts.

Hazards: none (wouldn’t eat it, but PVA is used as a synthetic gum base in some chewing gums)

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Scenic Accent Glue

This woodland scenery detail glue that is removable and flexible to hold small details like figures easily but have some give if they are touched. Allows you to pull up the figure and replant a few times. Seems to be an odd mixture of maybe a PVA glue and rubber fillers.

Works on: small details like figures or items that may need a more flexible bond.

Doesn’t work on: seems to stick to most stuff but its easy to pull off.

Drying time: Dries fast - few minutes to set up.

Strength: Holds loosely and flexibly. You can pull up object and tack down again a few times.

Flexibility: glue drys flexible

Color when dry: Clear

Application: toothpicks, micro applicators

Waterproof: yes

Dilute: don’t think thinnable

Cleanup: wipe clean. Residue can be peeled off.

Stability: probably a few years

Best used on: small details that need a flexible bond that can easily be removed and tacked done again a few times.

Hazards: relatively no odor

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Rubber Cement

Good old rubber cement is exactly what its name says, it’s rubber. Rubber compounds dissolved in a solvent line n-heptane dries to a flexible bonding agent of rubber. Allows for a flexible bond that can be peeled off most surfaces.

Works on: most all surfaces

Doesn’t work on: seems to stick to most stuff but its easy to pull off and not great as a very long term bond.

Drying time: Dries fast - few minutes to set up.

Strength: Holds loosely and flexibly. You can pull it off most surfaces except for very porous surfaces like fabrics.

Flexibility: glue drys flexible

Color when dry: Clear to slightly yellowed

Application: toothpicks, micro applicators, brushes

Waterproof: yes

Dilute: can be thinned with n-heptane rubber cement thinner

Cleanup: wipe clean. Residue can be peeled off.

Stability: probably a few years and can be revived with adding rubber cement thinner

Best used on: small details that need a flexible bond. Good for paste up of sheets of material.

Hazards: n-heptane is an organic solvent and should be used in a ventilated area.

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Polyethlene Solvent - Humbrol Liquid Poly, Slaters MekPak, etc

Powerful ethylene based liquid solvents that can glue practically any plastics, even very hard/smooth ones, by melting them together.

Works on: Most anything plastic: plasticard, injection moulded kits, plastic loco bodyshells, etc.

Doesn’t work on: Metals, fabrics, cellulose based materials (wood, card), not plastic based materials that the solvent cannot melt.

Drying time: Under a minute.

Strength: Virtually unbreakable as it melts the parts together forming a bond as strong as or stronger than the original plastic.

Flexibility: Totally inflexible.

Colour when dry: Clear, but mostly evaporates rather than drying

How It Works: Solvents causes plastic to depolymerize some and when solvent evaporates plastic repolymerizes and the two parts are fused together.

Application: As a thin liquid is best applied by brush. Some brands include a brush built into the lid (Humbrol) or sell a separate brush (Slaters). Regular paint brushes can be used but some brush materials may disintegrate when exposed to the solvent.

Waterproof: Absolutely waterproof.

Dilution: Cannot be diluted. Use in small, restrained amounts.

Cleanup: Will evaporate if spilled but large amounts may damage the surface before evaporating. Wipe up while in liquid form using disposable wipes.

Stability: Lasts for years if properly stored in the original airtight glass bottles it comes in. If improperly stored will evaporate in a matter of weeks.

Best used on: Polyethylene and Polypropylene. Hard plastics that resist the usual plastic glues. I find it very useful for assembling Tsugawa HO products that are made in a very hard, shiny plastic quite different to ordinary hobby plastics, to which the usual Revell or Tamiya will not form a strong bond. Also useful for applications where the joint has to support a lot of mass or stress, such as on a very large and heavy model, or an object that will be handled frequently.

Hazards: These are organic solvents so should be used in a well ventilated area. Small 5v computer fan on the bench blowing away from you should help remove and diffuse the evaporating solvents.

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Plastic Model Cement - Testors, etc

Toluene based solvent glue that contains dissolved polystyrene

Works on: polystyrene and ABS

Doesn’t work on: Metals, glass, polyethylene, polypropylene

Drying time: few minutes

Strength: very strong bond with polystyrene and ABS plastics, basically fuses them

Flexibility: Totally inflexible.

Colour when dry: Clear

How It Works: Solvents causes plastic to depolymerize some and when toluene solvent evaporates plastic repolymerizes along with dissolved polystyrene in the glue and the two parts are fused together.

Application: glue is thick so usually applied from the tube or with toothpicks or micro applicators.

Waterproof: Absolutely waterproof

Dilution: Cannot be diluted

Cleanup: on plastic once dry it needs to be cut off as fused with the plastic. Can be removed on other non plastic surfaces and skin with strong organic solvents like acetone.

Stability: Lasts for a few years if tube is well sealed

Best used on: Polystyrene and ABS plastics. Most plastic models

Hazards: Toluene is an organic solvents so should be used in a well ventilated area. Small 5v computer fan on the bench blowing away from you should help remove and diffuse the evaporating solvents.

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General Purpose “Impact” Adhesive - Uhu, Evostick, etc

'Universal' fast-drying high strength glue.

Works on: Almost any material; wood, paper, plastic, metal etc.

Doesn’t work on: Expanded foams such as polystyrene packaging or insulation foam. It dissolves them.

Drying time: Forms strong bonds in seconds which set solid after half an hour. Applying pressure to the assembly reduces drying time (hence 'impact' adhesive). Spills and excess dry to a gummy consistency in about half an hour.

Strength: Very strong given a large contact surface. Small contact surfaces can produce weak joints.

Flexibility: Fairly flexible, spills and excess can simply peel off, and parts glued with it can be peeled apart provided that not too much glue has been used.

Colour when dry: Clear and gummy. May stain surfaces a dirty brown after a few years.

How It Works: Exposure to air or pressure vapourises methyl acetate, causing the glue to set in a clingy, semi-solid layer between parts holding them together without being absorbed by or changing the parts themselves.

Application: Best applied directly to the joint from the tube nozzle. Very stringy and sticky so liable to make a mess if first decanted and then applied by a stick or other means. Some people decant it into applicator bottles with thin nozzles for fine application.

Waterproof: Yes.

Dilution: As a semi-liquid gel it cannot really be mixed with other substances and so cannot be diluted.

Cleanup: Very easy to clean up once dried as it forms a clear gum that can be peeled or rubbed off most surfaces.

Stability: Lasts for months provided the tube is firmly closed when not in use. Stability when decanted into bottle depends on how airtight the bottle is.

Best used on: Mixed media creations where very different materials are used together that won't naturally or easily bond. For example; fitting a plastic roof to a paper kit building. Also helpful where you want to be able to separate the parts in future.

Warnings: Releases methyl acetate vapours which are flammable and irritant. Do not use near fireplaces or candles or while smoking. Use in well ventilated area.

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Contact Adhesive - 3M and others

Strip of only pressure sensitive adhesive on a tape carrier strip. Like double stick tape but no film layer in the center, only adhesive. Used to attach car detailing strips, cell phone screens, etc.

Name/company: 3M VHB

General Description: Like a double-stick tape, the adhesive part only. It is an acrylic adhesive. Comes in rolls and sheets of different thicknesses.

Works on: Plastics, metals, glass, ceramic, paper, cardstock, wood. Better for non-porous surfaces, but will work on porous surfaces.

Doesn’t work on: Hard to use on non-flat, uneven surfaces.

Drying time: Instantly bonds. The bond strength improves over time - up to 1 hour at room temperature.

Strength: Very strong, but it can be de-bonded - especially when first applied.

Flexibility: Very flexible.

Color when dry: Varies. The 2 mil/50 um thick material is clear.

How It Works: The adhesive is inherently sticky. It is supplied on a paper carrier tape until ready to use.

Application: Comes on a roll with a paper carrier/backing. Surfaces should be clean and dry. I am using it at 2 mils/0.05 mm/50 um thick. This can be challenging to cut and handle. It is best to cut it to size on the carrier, then apply it to one surface and smooth. Peel off the carrier. Align to mating surface carefully. Press together and hold. Clamp for up to 1 hour for strongest adhesion, but clamping is not necessary. It will not slide. If you misalign the pieces, you will need to peel the two pieces apart and probably remove the adhesive and start over.

Waterproof: Claimed to be good for damp environments. I haven't used it in wet situations.

Dilute: Not applicable.

Cleanup: Peels or rolls off. Isopropyl alcohol may take off residue.

Stability: Guaranteed for 24 months after manufacture. I think it will last much longer if stored reasonably well.

Best used on: Flat surfaces. Applications where you can align the two pieces carefully before sticking together.

Warnings: May damage some surfaces when de-bonding - peeling off paint, etc. Will rip up surface of paper or cardboards if you attempt to peal it off.

Data: https://www.3m.com/3M/en_US/vhb-tapes-us/

Where I bought my roll: https://www.uline.com/BL_6063/3M-F9460PC-VHB-Adhesive-Transfer-Tape

This is more of this material than I am likely to use in a lifetime.

July 6, 2021

Name/company - Tamiya Craft Bond

General Description - White water based glue. Dries clear. Perfect for dioramas and paper products.

Works on: what material and/or surface does it bond well to It is compatible with paper, wood, fabric, leather, foam board, and styrofoam.

Doesn’t work on: what materials and/or surfaces doesn’t it bond well to - bonds to most materials that I have tried but best for paper, foam core, polybak (laser board)

Drying time: seconds, days - Dries fast - a minute or two.

Strength: how good does it hold - Holds well, strong bond.

Flexibility: is the bond at all flexible when dry - Compared to standard wood glues, this craft bond dries into a softer consistency to help provide shock protection.

Application: how to best apply it or tricks and tips. - Glue bottle has a fine tip. Great for accurate application.

Cleanup: can you clean off excess easily and is solvent needed - Cleans with water while still wet. Damp cloth works.

Stability: how long/well does the glue last in container after opening - a few months is the longest I've let one sit.

Best used on: what materials/things is this your go to Paper structures is what I use it for the most. Like Sankei buildings. Also, it does not transfer excessive water to paper, so the joints remain wrinkle-free. Looks like a white PVA glue but dries very fast and achieves a very strong (transparent of course) bond. Good for clear parts.

October 20, 2022

A follow up on Tamiya Craft Bond glue. A shipment arrived today from a Toronto hobby supplier. There is now English language instructions and safety warnings on the back of the package.

"Bond will harden in 15-20 minutes and reach maximum strength after 24 hours (at 20 degrees Celsius)."

Just for the record the supplier was Sunward Hobbies. Not a model railroad supplier, but a place where pick up small tools and other supplies for the layout.

https://www.sunwardhobbies.ca/tamiya-craft-bond-general-purpose-glue-87078/

Edited October 20, 2022 by bill937ca

January 20, 2023

Polyethlene solvent - Humbrol Liquid Poly, Slaters MekPak, etc

Powerful ethylene based liquid solvents that can glue practically any plastics, even very hard/smooth ones, by melting them together.

Works on: Most anything plastic: plasticard, injection moulded kits, plastic loco bodyshells, etc.

Doesn’t work on: Metals, fabrics, cellulose based materials (wood, card), not plastic based materials that the solvent cannot melt.

Drying time: Under a minute.

Strength: Virtually unbreakable as it melts the parts together forming a bond as strong as or stronger than the original plastic.

Flexibility: Totally inflexible.

Colour when dry: Clear, but mostly evaporates rather than drying

Application: As a thin liquid is best applied by brush. Some brands include a brush built into the lid (Humbrol) or sell a separate brush (Slaters). Regular paint brushes can be used but some brush materials may disintegrate when exposed to the solvent.

Waterproof: Absolutely waterproof.

Dilution: Cannot be diluted. Use in small, restrained amounts.

Cleanup: Will evaporate if spilled but large amounts may damage the surface before evaporating. Wipe up while in liquid form using disposable wipes.

Stability: Lasts for years if properly stored in the original airtight glass bottles it comes in. If improperly stored will evaporate in a matter of weeks.

Best used on: Hard plastics that resist the usual plastic glues. I find it very useful for assembling Tsugawa HO products that are made in a very hard, shiny plastic quite different to ordinary hobby plastics, to which the usual Revell or Tamiya will not form a strong bond. Also useful for applications where the joint has to support a lot of mass or stress, such as on a very large and heavy model, or an object that will be handled frequently.

January 20, 2023

Thanks space beaver! I’ll add it to the list. Been meaning to add the new loctite 2 part glue for poly ethylene. Put some on each piece and push together and fast fusion. It’s a polymerization and dines not see to the a solvent/fusion reaction. I’ve used it on a few parts around the house that take a lot of stress and it’s held very well!

cheers

jeff

January 22, 2023

Impact Adhesive - Uhu, Evostick, etc