Adjusting lens hood thread

[Joao]

Hello
I just bought a lens hood with a 29.5 mm thread diameter. It fits the inner thread in front of the camera lens but it wobbles a little, and if I pull it in certain positions it comes out . I do not trust it as it will certainly fall if I use it. I believe the threads (of the camera ? of the hood? both ?) might be worn out .
Question : Is there any easy way to ajust the hood or to slightly increase the thread(s) diameter(s) in order to attach the hood in a way that it does not fall ?? Any sort of thick material that I can apply ??

Obviously I am not thinking in attaching it permanently ....

Thank you for your input
Regards
Joao

 

[ruby.monkey]

Wrap the hood's thread with electrical tape until you get a tight fit.

 

[santino]

Maybe a bit of loctite... apply and let it dry. Then you should be able to unscrew the hood with a little bit of force.

 

[Joao]

Thank you

@ruby.monkey - electrical tape did the job for now. But I needed to cut a narrow (3-4 mm wide) stripe of tape and apply it on the thread. I'm afraid that it will not last long and will need to be replaced quite often

@santino - I was not aware of "loctite" products, they seem to have a thread sealant that may be a more definitive solution.

I am grateful for your tips

Regards
Joao

 

[Dan Daniel]

Are you taking the hood on and off all the time?


A paper tape like masking tape will also work, and is much less prone to slide off. Use a 'classic' thin masking tape, not a new blue or green temporary masking tape.

 

[Dwig]

Are you taking the hood on and off all the time?


A paper tape like masking tape will also work, and is much less prone to slide off. Use a 'classic' thin masking tape, not a new blue or green temporary masking tape.

Never ever use classic white paper "masking" tape for anything other than paint masking or a few other very very temporary uses. If left applied for an extended period the adhesive hardens and makes a big mess.


There are similar tapes from 3M that use a different adhesive that, while less durable against paint solvents, is safe for long period application. These are sometimes sold as "artists" tape. Here's a link to 3M's page for their product, #200: https://www.3m.com/3M/en_US/company...M-Paper-Tape-200/?N=5002385+3293194312&rt=rud

 

[View Range]

I recommend teflon pipe thread tape. It fills the gap and is not adhesive.

 

[xavyr]

I recommend teflon pipe thread tape. It fills the gap and is not adhesive.

Yep; that's the stuff right there.

 

[presspass]

Another vote for Teflon plumber’s tape. Wrap it in the direction of the thread so it won’t bunch up.

 

[farlymac]

Or you could get a hood with the proper size. Sounds like you have a 30mm filter mount.


PF

 

[David Hughes]

The (? blue) Loctite stuff sold by gun dealers for trigger adjustment securing is probably the best. Very useful for loose screws and nuts all over the place...


Regards, David


PS 2nd choice is the white sealant tape and that doesn't have a short shelf life but is fiddly to use precisely.

 

[raydm6]

Teflon tape recommendation is a good idea.

I'd be careful of using Blue Loctite (242) and to a lesser extent Purple Loctite (222) - which is really good for tiny eye-glass size screws by the way - in this application. Plus, the blue breaks up and gets powdery when dis-assembling and can be a bit of a dusty mess.

Also, an alternative - Vibra-Tite - an adjustable/reusable thread-locker, can be used to build up that slack in the threads:
https://www.vibra-tite.com/threadlo...ble-threadlockers/vibra-tite-vc-3-threadmate/

 

[Joao]

@Dwig - I don't take the hood all the time, but I replace it for a slip-on lens cap when I am not using the camera. I don't want a permanent fixed hood.

@farlymac - It is possible that a the size was not well measured. The 29,5 mm measure was the most apropriate size I could find with a caliper. I think that the wobbling is more due to wearing of the threads than to the wrong size. Moreover, this hood will also fit a Kodak Retina thread, so it will not be lost.


My next choice will be the Teflon tape mentioned in several posts above. The lack of adhesive will make it easier to cut it in the right size.
I will leave the Loctite liquids as my last option.

Thank you all for the sugestions

Regards

Joao

 

[Dwig]

@Dwig - I don't take the hood all the time, but I replace it for a slip-on lens cap when I am not using the camera. I don't want a permanent fixed hood. ...

Regards

Joao

I wasn't thinking you were. It's just that regular masking tape could make it nearly permanent if left on too long.


Also, I would not recommend either blue or red Loctite. They require too much force to break their grip. If you use Loctite, use the low strength purple.

 

[raydm6]

I wasn't thinking you were. It's just that regular masking tape could make it nearly permanent if left on too long.


Also, I would not recommend either blue or red Loctite. They require too much force to break their grip. If you use Loctite, use the low strength purple.

Yes, don't put RED Loctite on anything you want to take apart! If you do, you will need to apply >550deg.F heat to loosen the bolt.

Red Loctite is applicable for larger size bolts anyway that you won't find in cameras - 1/4 Dia. and greater.

As I wrote above also, I too agree with the use of Purple Loctite 222 as a maximum - but maybe not in this application.

 

[Rob-F]

Or you could get a hood with the proper size. Sounds like you have a 30mm filter mount.
PF

That's what I'm wondering. I didn't even know there was a 29.5mm filter thread. Is the hood made by the same brand as the lens?

 

[David Hughes]

FWIW, the thread locking Loctite was the only one available when I started using it. Looking at the range nowadays I am amazed.


Regards, David

 

[xavyr]

What camera and lens?

 

[farlymac]

@Dwig - I don't take the hood all the time, but I replace it for a slip-on lens cap when I am not using the camera. I don't want a permanent fixed hood.

@farlymac - It is possible that a the size was not well measured. The 29,5 mm measure was the most apropriate size I could find with a caliper. I think that the wobbling is more due to wearing of the threads than to the wrong size. Moreover, this hood will also fit a Kodak Retina thread, so it will not be lost.

My next choice will be the Teflon tape mentioned in several posts above. The lack of adhesive will make it easier to cut it in the right size.
I will leave the Loctite liquids as my last option.

Thank you all for the sugestions

Regards

Joao

Yeah, Kodak always measured the outside diameter of the filter ring, mostly because they were pushing the Series Filters and Adapters, that's how you get 29.5mm actual when Kodak says 32mm.

That said, for thread size approximation usually it's two mm smaller than the outside diameter of the filter mount, as most lens barrels are 1mm thick. There are exceptions, just like the Kodak Retinas, but generally deducting 2mm will give you the proper filter size.

PF

 

[Joao]

@farlymac: "... for thread size approximation usually it's two mm smaller than the outside diameter of the filter mount,.." The outer diameter of the barrel is 30,6 mm. My decision in choosing the hood was based on the inner diameter (29,4 mm) .
But I took good note of your advice on choosing the correct filter diameter.

@xavyr - The camera is a FSU Yunost (or Junost) made by GOMZ in the late fifties. Lens is a fixed T-32 3,5/45mm. In spite of being a recessed lens , it is very prone to flare



I already have the Teflon tape. Will try some shots tomorrow.

Thank you again

Joao