Since we love to talk about glues

xkaes · Jun 23, 2025

Instead of doing a SEARCH, I decided to start a new thread. Besides every situation is different.

I've got a piece of Bakelite that has fallen apart -- into three pieces -- probably from someone putting too much stress on a locking bolt.

Anyway, I'm wondering if there is a glue that will put Humpty back together again?

Kino · Jun 23, 2025

Bakelite is a tough one. When I was trying to repair old radios, I never really found a good glue for that material that was strong and not incredibly ugly after drying.

Might want to drill and place some wire pins in the part (in addition to the glue) if it takes any stress at all.

Avoid foaming glues like Gorilla Glue!

retina_restoration · Jun 23, 2025

xkaes said:
Instead of doing a SEARCH, I decided to start a new thread. Besides every situation is different.

I've got a piece of Bakelite that has fallen apart -- into three pieces -- probably from someone putting too much stress on a locking bolt.

Anyway, I'm wondering if there is a glue that will put Humpty back together again?

An epoxy resin is generally best for these kinds of plastics.

4season · Jun 23, 2025

I am a fan of the original, 2-part gray JB Weld. As a bonus, it can be shaped when it has set but not fully cured.

Dan Daniel · Jun 23, 2025

I think it was based on a recommendation here that I tried Milliput epoxy modeling putty. I needed to build out the corner of a Rolleiflex metal casting. The black worked well, and a little stippling with a Testors black modeling paint got me a nice match.

Milliput - The epoxy putty with a thousand uses in modelling, DIY and industry

Milliput is one of the world's leading producers of epoxy putties. It is adhesive to most materials, tough and durable, and self hardening.

www.milliput.com

But I did like Kino suggested- added some wire pins. Drilled a couple of holes into the main body, put music wire pegs in so that they would be fully covered after final shaping. I am a big believer in multiple securing methods if possible. Each will have a failure mode of some sort. I have also used drill holes to allow epoxy flow in to form 'pegs; to reinforce in a situation where other materials weren't possible. So if pins won't work, think abut making divots or such to give the adhesive more both grab area and structural support.

ivan35mm · Jun 25, 2025

yes, plastics with low surface energy (polypropylene, nylon, polyethylene, bakelite, etc) are notoriously difficult to bond.

you might have some luck with a special 2 component adhesives (check out Loctite 3035). this will require a dual applicator gun for cartridges.

i don’t recommend epoxy, unless you know how to properly surface prep, and even then, the bond still might fail…

if you wish to use epoxy, use West Systems G/Flex 655. but properly abrade/scuff the surface and degrease with appropriate solvent, so that the adhesives has something to help mechanically bond to the Bakelite

blee1996 · Jun 25, 2025

I use JB Weld 2-part epoxy glue with steel enforcement, and have been successful with all kind of materials.

F4U · Jun 25, 2025

No mention was made as to what the object is or the area of it that is broken.

snusmumriken · Jun 26, 2025

I've become quite a fan of UHU 'Hart' glue for small repair jobs, although I've not tried it on bakelite. It's a single component glue, quite thin, transparent and sets very hard. Comes in a tube.

I wouldn't suggest any epoxy myself, because it's difficult to avoid a thick and ugly glue line.

xkaes · Jun 26, 2025

F4U said:
No mention was made as to what the object is or the area of it that is broken.

Not that it makes a difference, but it is a ring around a lens with a lock bolt to keep the lens position in place. I suspect someone screwed in the lock bolt too tight and the ring split into three pieces.

I'll probably try the gray JP Weld since the bakelite is also gray. The lens can be used without the ring, it just can't be locked in place.

Nokton48 · Jun 26, 2025

I use JB WELD all the time, recently to repair Broncolor Light Stands. Incredibly useful for filling holes in Sinar Norma Lensboards.

APSC Sony Nex C3 JB Welded to Peco Rear Standard Plate by Nokton48, on Flickr

I bought this Nex C3 16mp Body for Fifty Bucks at World of Photography. Then I JB Welded it to a flat scrap black metal Plaubel Plate from my junk box. Then JB Welded the flat plate/APSC Back to a flat revesible Peco Junior Rear Plate. VOILA! "Poor Man's Medium Format Digital Back". Great for testing and trying different OLDE lenses.

F4U · Jun 26, 2025

xkaes said:
Not that it makes a difference, but it is a ring around a lens with a lock bolt to keep the lens position in place. I suspect someone screwed in the lock bolt too tight and the ring split into three pieces.

I'll probably try the gray JP Weld since the bakelite is also gray. The lens can be used without the ring, it just can't be locked in place.

I changed my life greatly when I bought a 3D printer and studied Freecad. Very soon, many of the things I had fretted about trying to figure out how to repair, I simply reverse engineered and produced a replacement for. In most cases my new part was actually better than the original.

r_a_feldman · Jun 26, 2025

blee1996 said:
I use JB Weld 2-part epoxy glue with steel enforcement, and have been successful with all kind of materials.

I have successfully used JB Weld with steel on the baffle hinge of a Weston Master (715) meter, which might be bakelite. I had the baffle off the meter and applied slightly more JB Weld than needed, sanding down the excess after it cured to match the contours of the hinge. I have also used JB Weld on a 35mm bulk loader that suffered multiple fractures.

xkaes · Jun 26, 2025

A lot of bulk loaders appear to be Bakelite.

bernard_L · Jun 27, 2025

I use 2-part epoxy.

Clean surfaces with alcohol
Smooth/shiny surfaces must be dulled with abrasive paper -- clearly not necessary for broken parts
Think and plan in advance how you will hold the parts together while the glue sets
Broken parts will often fall naturally into the correct relative position; but practice that assembly so you can do it without hesitation once it's for real (with the glue on)

DREW WILEY · Jun 27, 2025

If it's a threaded bolt section, consider holding the broken pieces together while the glue is setting with a nylon or teflon nut resistant to the glue, which can be subsequently backed off. Phenolic resin like Bakelite will accept a number of types of adhesive, while plastics like nylon, polyethylene, polypropylene, and teflon do not. One can always to a haze test with acetone or lacquer thinner in advance to determine susceptibility. There's a reason nearly all glues come in polyethylene containers.

The last serious assembly project I did with phenolic sheeting involved a non-foaming urethane glue, plus clamping pressure of course. But I always keep on hand a variety of epoxies too, including JB Weld.

xkaes · Jun 27, 2025

Fortunately, the threaded hole for the locking bolt is NOT in one of the three cracks. It would be much more difficult to put together if that had happened.

And I just found yet another item that can benefit from some JB WELD.

Since we love to talk about glues

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