Help w/ Dimensions of Lighter O' Ring

[Alvin777]

Hello lighting friends.

I'm doing my best to revive a beautiful vintage lighter (the body has a rough diamond on a rock and that's sealed in acrylic), the gas would leak out (dangerous coz' there'll be flame around your hand) the valve where the length of the flame is adjusted coz' the O' ring's old (I even put food grade silicon grease used in lavatories). Upon measuring with a caliper, this is the current dimension of the O' ring (the O' ring is old, the original size may have become smaller or larger. OD = outside diameter, ID = inside diameter, CS = cross section):

OD: 4.92mm
ID: 3.5mm
CS: 0.75mm

O' ring height: 0.76mm

What could be the real dimensions when it was new? And where can I buy a compatible O' ring?

I came across a seller who sells these sizes, I wonder if one is compatible:

3 x 0.8mm 30Pcs
2.8 x 0.6mm 30Pcs
4 x 1mm 30Pcs
4.5 x 1.5mm 30Pcs
4 x 1.5mm 30Pcs
4.5 x 1mm 30Pcs

Their priced between US$2.33 to US$2.56

Thank you, God bless, Rev. 21:4

 

[scalpel_ninja]

Hello lighting friends.

I'm doing my best to revive a beautiful vintage lighter (the body has a rough diamond on a rock and that's sealed in acrylic), the gas would leak out (dangerous coz' there'll be flame around your hand) the valve where the length of the flame is adjusted coz' the O' ring's old (I even put food grade silicon grease used in lavatories). Upon measuring with a caliper, this is the current dimension of the O' ring (the O' ring is old, the original size may have become smaller or larger. OD = outside diameter, ID = inside diameter, CS = cross section):

OD: 4.92mm
ID: 3.5mm
CS: 0.75mm

O' ring height: 0.76mm

What could be the real dimensions when it was new? And where can I buy a compatible O' ring?

I came across a seller who sells these sizes, I wonder if one is compatible:

3 x 0.8mm 30Pcs
2.8 x 0.6mm 30Pcs
4 x 1mm 30Pcs
4.5 x 1.5mm 30Pcs
4 x 1.5mm 30Pcs
4.5 x 1mm 30Pcs

Their priced between US$2.33 to US$2.56

Thank you, God bless, Rev. 21:4

Usually the OD is the sum of the ID plus CSx2.

So it might be ID 3.5mm, CS 0.75mm, OD 5mm.

Also, any idea where and when the lighter was made? Country of origin might also direct if the measurements should be in mm or inches.

 

[scalpel_ninja]

If you have access to a physical hardware store, perhaps you can bring the old O-ring to compare and look for a 0.75 x 3 size.

 

[Fuzzywuzzies]

Any clues as to Imperial vs Metric will be a great start.
Quite a bit of my work involves custom sizes of O-rings, so I can say from experience that it's always best to measure the actual groove / mating parts on both sealing components, if at all possible.
I have you considered the compound required? (Nitrile, Viton, etc.). I use Viton with my Exotac fluid lighters.

 

[Alvin777]

Any clues as to Imperial vs Metric will be a great start.
Quite a bit of my work involves custom sizes of O-rings, so I can say from experience that it's always best to measure the actual groove / mating parts on both sealing components, if at all possible.
I have you considered the compound required? (Nitrile, Viton, etc.). I use Viton with my Exotac fluid lighters.

Hi thanks for the replies.

The groove (this is on the lighter part: above the thread on the hole where the valve for the flame length control is screwed in) if I measured the right part is: 4.4mm.

The shaft of the valve (where the original O' ring was, which has shattered into pieces coz' it's brittle) is 3.5mm on average.

Thanks again in advance.

 

[Alvin777]

Usually the OD is the sum of the ID plus CSx2.

So it might be ID 3.5mm, CS 0.75mm, OD 5mm.

Also, any idea where and when the lighter was made? Country of origin might also direct if the measurements should be in mm or inches.

Hi, thanks for all the replies. I checked only engraving at the bottom of the part where you push your thumb onto to ignite the lighter is: "GAS"

If I were to make this O' ring (many trial and error- until there is no more leak and flames on the hand), what material would I be looking around the house (interior tubing of a bike? though I don't have that, I have old car tires though for the rubber)

 

[Fuzzywuzzies]

Hmm. I don't like your chances of manufacturing an O-ring without specialised equipment; especially one that small.
Do you have any photos?

 

[Alvin777]

Hmm. I don't like your chances of manufacturing an O-ring without specialised equipment; especially one that small.
Do you have any photos (the photo is the exact same one as mine)?

 

[Fuzzywuzzies]

Here are the two smallest O-rings in standard kit, for both metric and imperial. I've included a shot of the stated dimensions for each as well, for comparison.
I've also sent away an enquiry to a supplier to see if we can find a Viton O-ring matching those dimensions. I'll let you know what comes back.

 

[Fuzzywuzzies]

Right-O. I can get a Viton O-ring in 5.0x3.0x1.0mm, or 5.5x3.5x1.0mm. Is that any help to you? More than happy to get some and send them to you - DM me if you like.

 

[Alvin777]

Hi, I'll keep that in mind (I have to be honest, among the things being restored, this is moderate priority compared to others unrelated to lighters to be revived). Thanks again for the offer. God bless, stay safe.