Best Glue for Bakelite

What is the best glue to use for Bakelite?

Bakelite is a hard, infusible and chemically resistant plastic, and the Selleys recommendation for it is a two-part epoxy. Selleys 5 Minute Araldite Epoxy is the starting point. If you need more working time than five minutes allows, step up to Araldite Super Strong, a two-part epoxy that holds up to 150 kg/cm².

Before you buy anything, be completely certain the plastic is Bakelite. Selleys makes this the first condition of the recommendation, and there is a good reason: an epoxy that grips Bakelite firmly may not grip a modern moulded plastic at all, and the epoxies in the range will not bond PTFE, polyethylene or polypropylene under any circumstances. Vintage radio cases, telephone handsets, switch plates and camera bodies are commonly Bakelite; a similar-looking item made after about 1960 usually is not.

Choosing between the two

Property	Araldite Super Strong	Araldite Extra Time
Set time	5 minutes	60 minutes
Working life of mixed glue	2–3 minutes at 20°C	1 hour at 20°C
Initial bond time	30 minutes	6–8 hours
Maximum bond time	After 16 hours	After 24–72 hours
Holds up to	150 kg/cm²	150 kg/cm²
Temperature resistance	Up to 60°C	Up to 80°C
Colour	Dries clear	Dries translucent
Packaging	8 mL and 24 mL syringes, 35 mL tube	200 mL tube

Indicative data only, not intended for the preparation of specifications.

A note on working time

This page has historically described Araldite Super Strength as giving "a working time of up to 2 hours". The current technical data sheet for Araldite Super Strong 5 Minute Epoxy does not support that: the mixed glue remains usable for 2 to 3 minutes at 20°C and the product sets in 5 minutes.

If a long working time is genuinely what your repair needs — a shattered Bakelite case with several fragments to align, say — the product that provides it is Araldite Extra Time, which stays usable for a full hour and sets in 60 minutes. It is also the tougher choice thermally, rated to 80°C rather than 60°C. Its cost is patience: initial bond takes 6 to 8 hours and maximum strength 24 to 72 hours.

Why epoxy suits Bakelite

Bakelite is a thermoset. It does not soften and re-fuse when heated, which rules out solvent welding and hot-melt approaches that work on thermoplastics. It is also chemically resistant, so a solvent-based adhesive has nothing to bite into — it cannot partially dissolve the surface the way it can with acrylic or PVC.

That leaves mechanical and chemical adhesion to a prepared surface, which is exactly what a two-part epoxy does well. It also explains why the surface preparation step below is not optional. The published strength figures are measured on clean, abraded surfaces, and Bakelite that has been polished or waxed over decades will give a fraction of that.

How to do the repair

1. Abrade, clean and dry both faces. Fine abrasive along the break line, then remove all dust. Old Bakelite often carries wax or polish — remove it.
2. Dry-fit the pieces first and work out how you will hold them. With a 2 to 3 minute working window there is no time to improvise clamping after the glue is mixed.
3. For a syringe, snap out the cap from the plunger and cut the sealed tips at the end of the nozzle. For a tube, pierce each tube with the spike in the top of the cap.
4. Dispense equal parts of both liquids onto a clean disposable surface and mix thoroughly with a spatula. Do not mix in the plastic blister. Mix small quantities — larger amounts cure faster.
5. With Extra Time, mix, leave for 5 minutes, then mix again before applying.
6. Apply the mixed glue to both surfaces of the job, then bring them together.
7. Do not apply undue strain to the bond for 30 minutes (Super Strong) or 6 to 8 hours (Extra Time). Hold the join with tape or weights.
8. Leave until maximum strength is reached: 16 hours for Super Strong, 24 to 72 hours for Extra Time. Allow longer in colder weather.
9. Clean up uncured Araldite with acetone. Test acetone on a hidden area of the piece first — it will not harm Bakelite, but it will harm many of the plastics people mistake for Bakelite.

Limitations

• Will not bond PTFE, polyethylene or polypropylene plastics. If your item turns out to be one of these, Selleys directs you to All Plastics instead.
• The bond softens above the rated temperature — 60°C for Super Strong, 80°C for Extra Time — with strength restored when the temperature returns to normal.
• The product may discolour if exposed to UV. On a dark Bakelite item a visible glue line on a sunlit shelf will yellow over time.
• Allow longer bonding times in colder weather.
• Pre-test on leather and rubber to determine suitability.
• The Araldite data sheets carry no approval for food or drinking water contact. If the item is a serving piece, do not return it to that use.

Safety: on a two-part epoxy, the hardener is the hazard

Both Araldites named above carry the signal word Danger, and on both it is the hardener rather than the resin that earns it — which is the opposite of what most people assume.

Araldite 5 Minute: Part B, the hardener, is classified for skin corrosion, Category 1C (causes severe skin burns), eye damage, Category 1 (causes serious eye damage) and skin sensitisation, Category 1 (may cause an allergic skin reaction). Part A, the resin, is classified for skin and eye irritation and skin sensitisation.

Araldite Super Strong splits the same way. Part A is signal word Warning — H315, H319, H317, transport Class 9. Part B is Danger — H314, causes severe skin burns, with eye damage Category 1 and H317, transport Class 8 (corrosive). Both parts carry H317.

Read that against the two-to-three minute working window. You dispense, mix, apply to both faces and assemble a small fiddly vintage object held in your hand, all inside two to three minutes. Time pressure is what makes people mix with a finger, steady a piece bare-handed, or wipe a spatula on a trouser leg — which is how undiluted hardener reaches skin. Get the gloves on and the clamping dry-fitted before you mix, which this page already tells you to do for a different reason.

H317 is the classification that ends epoxy work for people. Skin sensitisation is not irritation that settles when you wash your hands. It is the immune system learning to react — generally permanent once acquired, and afterwards triggered by exposures far smaller than the one that caused it. It develops from repeated casual contact, so the person at risk is not someone who spills a syringe but someone restoring a collection of Bakelite pieces over a winter, handling a little uncured mix each time. Nitrile gloves every time, and mix on a disposable sheet you can throw away rather than a bench you will lean on later.

Eye damage at Category 1 is permanent, and the geometry here invites it: cutting the sealed tips off a syringe, piercing a tube with the cap spike, and squeezing two viscous liquids out at close range. Eye protection while dispensing. A splash needs a 15-minute flush and a Poisons Information call, not a rinse.

There is no milder epoxy in the range to switch to — Super Strong and Extra Time share the hardener profile, so product choice will not reduce this. Gloves, a disposable mixing surface and eye protection are the controls. One thing does change: the fallback this page names for plastics that turn out not to be Bakelite, Selleys All Plastics, is H225, highly flammable liquid and vapour, with H319 and H336 — so that route needs ventilation and no ignition source, which the epoxies do not.

Poisons Information Centre — 131 126 in Australia, 0800 764 766 in New Zealand.

Common questions about gluing Bakelite

How do I know if it is really Bakelite?

Selleys' condition is to be 100% sure before proceeding. If you are not sure, test the adhesive on a hidden area or an inconspicuous fragment first.

Which Araldite gives me the most working time?

Araldite Extra Time — the mixed glue remains usable for 1 hour at 20°C and it sets in 60 minutes.

How strong is the repair?

Both Super Strong and Extra Time hold up to 150 kg/cm² when fully cured on a clean, abraded surface.

Does the glue line show?

Super Strong dries clear and Extra Time dries translucent. On dark Bakelite a clear line is less visible than a translucent one, but neither is invisible.

Can I fill a missing chip as well as bond a break?

The Araldite data sheets cover bonding, not gap filling or moulding. For a missing section, treat filling as a separate job from the structural bond.

How long until I can handle it?

Do not stress the joint for 30 minutes with Super Strong, or 6 to 8 hours with Extra Time. Full strength comes later.

Can I sand or polish the cured epoxy?

Selleys does not publish sanding or finishing guidance for the Araldite range. Test any approach on a hidden area first.

How do I clean up a mistake?

Acetone on uncured product, before it sets. Once cured, removal is mechanical — see removing dried Araldite.

Why not a superglue?

Selleys nominates a two-part epoxy for Bakelite. Epoxy fills the small irregularities along an old break line, which a thin cyanoacrylate cannot do.