Strand Patt 243

[Stuart91]

I've got a few Patt 243 lanterns which are going to be refurbished and used as props.

 

We're struggling to get into one of them, as one of the bottom hinges seems to be completely seized. We've tried all the usual techniques but it's not budging. I'm worried that if we're any more brutal with it, we're going to snap something and write it off.

 

I figure I could probably get in through the back panel, but I thought I'd see if any has advice or suggestions before attacking any further.

[Don Allen]

This Loctite is the best spray I have used to release rusted parts Loctite LB 8040 Freeze & Release , you need to allow time for it or an equivalent to soak in.

[Stuart91]

This Loctite is the best spray I have used to release rusted parts Loctite LB 8040 Freeze & Release ,

 

Thanks, that definitely looks like it'll be worth a try. (And if it doesn't work for this, I'm sure we'll find other uses for it)

 

At the moment, the surrounding metal on the front panel is flexing before there's any give on the hinge. I'm beginning to wonder if it's been bent or damaged somehow in the past.

[dje]

I'm worried that if we're any more brutal with it, we're going to snap something and write it off.

 

Just wanted to add this is a completely valid concern.

 

Old 243s are surprisingly brittle and I have damaged one the past pushing something too hard.

 

So I would definitely go for the delicate option - as you are.

[Junior8]

Have you tried WD40? If a cleaning solvent won't work the only way might be to try to knock the hinge pins out with a pin punch but they are Mazek and this is delicate.

[Dave m]

a 50/50 mix of acetone and ATF is a very good penetrating solution used on old vehicles.

Maybe set the lantern up with a small dam made of plasticine to surround and flood the ears. Wait a few days.

 

 

Plus repeated hot/cold cycles.

Air duster in a can used upside down makes dry ice if you don't have any circuit board freezer.

 

[gareth]

Be very careful with the insulating discs between the lampholder and lamp tray - they're very likely to be asbestos.

[Stuart91]

Thanks, everyone. We've managed to get around the problem by removing the lens, since we could pry the front hatch out just enough to get into the top retaining clip.

 

With the lens away, we had just enough space to change the lamp holders etc. around inside.

 

My ordered Loctite 8040 is yet to arrive, but I'm sure it will come in handy for something else in future. Bathing the hinge in WD40 didn't get us anywhere so it would have been interesting to try the Loctite out. If it arrives before the lamps need to move on to their next owner I'll have a shot at the hinge again just to see.

 

Gareth - good point about the asbestos, thanks for the heads-up. The insulation certainly looks like asbestos. Fortunately we were able to fix the new lamp holder into the threaded holes on the old one. (After removing all the electrical contacts) So this has meant we were able to leave the insulation untouched.

 

I'm quite pleased with how the project has turned out, and it's nice to be able to give these venerable lanterns the opportunity of a new lease of life. Thanks again for all the pointers.

[gareth]

Glad you managed to get it done OK. For clarity, it's not the insulation on the cable that I'm talking about - there's an insulating disc sandwiched between the bottom of the lampholder and the lantern chassis, and that's what may well be asbestos, The venue I worked at for many years ended up having to get a specialist contractor in to remove the asbestos insulators from our old 243s in a ventilated 'tent' in our loading bay before we could dispose of them. (Had to do likewise with our old 793 followspots as well, just in case anyone reading this has any of those! Which suggests that certain vintages of 252 projector will probably also have these.)

[Stuart91]

it's not the insulation on the cable that I'm talking about - there's an insulating disc sandwiched between the bottom of the lampholder and the lantern chassis, and that's what may well be asbestos,

 

Yep - I worded it poorly. What we've got in these lanterns looks more like a gasket of sorts, it's trimmed to the footprint of the lamp holder, more or less. Definitely looked like asbestos, but we were able to leave it undisturbed.

 

The flex itself has clearly been replaced at some point, so all the lanterns have nice silicone flex. All I had to do was replace the 15amp plugs with 13 for domestic use.

 

It's always nice to complete a job without having to call out the guys in the bunny suits. ;)

[Junior8]

My ordered Loctite 8040 is yet to arrive, but I'm sure it will come in handy for something else in future. Bathing the hinge in WD40 didn't get us anywhere so it would have been interesting to try the Loctite out. If it arrives before the lamps need to move on to their next owner I'll have a shot at the hinge again just to see.

 

Just for clarity if any small white metal/Mazak/Zamak components are frozen it won't be rust unless this is in the pin/fixing/fastener if ferrous it will be something else. It might be corrosion - this material will corrode in certain circumstances - but it will often be muck. In the case of a lantern hinge of this sort the alternate expansion and contraction can allow ingress of all sorts of dusts which then get compressed. If I recall aright there isn't much clearance in this component. I think I would always start with a quick drop of good old 3in1 and leaving it a day or two or simply knocking the hinge pin out and doing the same. Never force white metal.

Edited May 9, 2021 by Junior8