Jump to content

Fixing Hookclamps


Shaun Foster

Recommended Posts

Most of our lanterns have the hookclamp atached with only an M10 nut and bolt and I was looking to replace these with wingnuts. I was also wondering what washers to use and in what position. I have found some 9mm dia wingnuts and bolts, are these safe to use or do I need to use 10mm or 12mm. Also, Is it possible to get wingbolts as some of out hookclamps have M10 bolts in making them very arkward to rig.

 

Thanks

 

Shaun

Link to comment
Share on other sites

From the bottom up:

 

M10 Bolt

Flat Washer

Trunion Arm of the lantern

Flat washer

Hookclamp

Flat washer

Sprung washer

Wingnut

 

I guess that a 9mm bolt would be safe enough, but it would be intensely annoying to have some bolts that look similar, but aren't exactly the same...

 

And a good hardware store should sell you m10 wingbolts.

Link to comment
Share on other sites

The other thing with using 9mm bolts is that if you ever want to mount your lanterns on stands, they won't fit into M10 spigots so you'll have to replace the bolt at that point anyway. M10 hardwar is cheap as chips - save yourself some grief later on, fit the right stuff now.
Link to comment
Share on other sites

you could use the wonders that are nylock nuts instead...

The disadvantage of these soon becomes obvious during a fit-up, when you often need to remove hook clamps from lanterns to mount them on stands, boom arms, etc. With ordinary M10 hardware you can largely do this without the aid of tools, only using a spanner for a final tightening-down. With Nylocks, it's spanners all the way, and consequently much slower. :angry:

Link to comment
Share on other sites

QUOTE 

I have found some 9mm dia wingnuts and bolts

 

 

I very much doubt it. There is no such thing as a M9 thread; M8 yes, M10 yes but M9 no.

Are you sure you're not mis-measuring M10?

 

Or *shudder* imperial.

Link to comment
Share on other sites

Our supplier for fasteners, tools and engineering equipment is - BML. They have branches throughout the Midlands and are very resonrable for fastensers. Failing that (If your outside Wales or Midlands - Screwfix is as good as any other.
Link to comment
Share on other sites

I have found some 9mm dia wingnuts and bolts

I very much doubt it. There is no such thing as a M9 thread; M8 yes, M10 yes but M9 no.

Are you sure you're not mis-measuring M10?

They must be M8 then, I didn't think M9 existed ether but they seem to measure bigger than 8mm, but are definitely not 10mm. I don't think they are imperial ether as they look pretty new.

 

 

Thanks again for all the info, next job is trying to get some money ;)

Link to comment
Share on other sites

Guest lightnix
From the bottom up:

M10 Bolt

Flat Washer

Trunion Arm of the lantern

Flat washer

Hookclamp

Flat washer

Sprung washer

Wingnut

Almost, I've always done it this way...

 

M10 Bolt

Flat Washer

Trunion Arm of the lantern

Flat washer

Sprung washer

Flat washer

Hookclamp

Flat washer

Nylon locking nut

 

This way, you don't automatically get a handful of washers if you remove the hookclamp and it is easier to do up the nut (less friction). With Nylocks, you can "pre-tension" the pan, so that it is loose enough to be moved with one hand while up a ladder, but still tight enough to count as locked off; that's the whole point of using the sprung washer, or so I was told.

Link to comment
Share on other sites

[They must be M8 then, I didn't think M9 existed ether but they seem to measure bigger than 8mm, but are definitely not 10mm. I don't think they are imperial ether as they look pretty new.

 

 

Thanks again for all the info, next job is trying to get some money :rolleyes:

They could be 3/8" whitworth, roughly 9.5mm. This was the old lighting standard (well one of them) before metrification.

 

shane

Link to comment
Share on other sites

Definitely sounds like Whitworth... I know their more English than Metric but Ugh!

 

I hate to disagree with the order... but I'd go for:

 

M10 Bolt

Flat Washer

Trunion Arm of the lantern

Hookclamp

Flat washer

nut (wing/nyloc/standard - whichever takes your fancy)

 

This arrangement will allow the best lockoff possible by the increased surface area

contact between lantern and hook clamp...

 

Also bear in mind that apparently (from what I remember at college) most manufacturers won't give a weight loading for a wing nut because it is made from cast rather than rolled steel... (I'm willing to be corrected on this one) Nylocs are great if you happen to have a couple of Andy's handy spanners in your back pocket... (another plug... more beer required!) although Wingnuts are easy to tighten with them as well...

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.