Looking for special glue

[Tranworld]

I have sourced a very cheap host torch which uses 3AAA but which I can easily convert to accepting 18650, I wanted to use 18650 since I have an ample supply of this type of cell.

The torch only cost about US$5 but has a reasonnably good LED and reflector. it has poor quality O rings which can be swapped for the better type and hence achieved good waterproofing.

There left just the front lens which is a simple push fit and perhaps (not sure) glued in, I have not been able to disassemble one yet as it it tight and I don't want to damage it. All I want to do now to seal the front lens off by applying a reasonnable bead of glue around the gap, but I don't know what is the best type of glue to use here.

a - Super glue will give off fume which will cloud the lens, I am not sure also of their waterproofing capability
b - silicone bath sealant is a little too difficult to spread without having it all over the lens itself
c - heat gun glue, well this may work BUT if it will melt if I left the torch in a car for example, here in Singapore the sun can reach heat it up to melting point
d - 2 part epoxy, too rigid and it may crack off.

I am sure some of you have a good idea somewhere, can you help?

 

[DM51]

Welcome to CPF, Tranworld.

I'll move your thread to the H&M section - someone there may have a solution for you.

 

[Omicron]

I have used window glazing compound around an aspheric lens, mainly to hold it in place. It would be at least water and weather resistant, but I'm not sure about sustained total immersion. It is easy to handle (I used a toothpick to work it in), a lot like clay.:welcome:

 

[Omicron]

On second thought, glazing compound may not stick to a plastic lens like it does glass.

 

[Hallmcc]

Try this stuff, it works great.

http://www.nrsweb.com/shop/product.asp?pfid=2291

 

[Cheapskate]

Silicone sealant can be applied very accurately in an o-ring like bead if you put some in a small syringe.

I would use epoxy for the job you have described. You can give some types a slight flexibility by using slightly more hardener than the the prescribed mix ratio calls for.

 

[Tranworld]

Thanks, the idea of silicone sealant applied from a syringe sounds good. Will try, it's not as if I am working on a US$100 torch here so it shouldn't matter if I experiment a bit

 

[Vinniec5]

How about RTV silicone in the pressurized can? The new power can system is very neat and it comes in different colors if needed Black/red/grey. loctite silicone can be found anywhere autoparts store/Kmart-Sears/online Looks like a can of spray cheese. We used to have alot of fun with that at when not actually sealing things with it. saves alot of time especially with oil & tranny pans

 

[Tranworld]

I don't know how the RTV pressurised can work, remember that I need to apply very precisely around a small diameter device, don't want any overspary here, beside I don't think I can find this in Singapore, they don't service car themselves and usually go to the service centre for that. Multi brick-a-brack store like K-Mart can't be found in Singapore.
But we do have a type of Japanese store called Daiso, they sell everything but everthing Japanese, so once again will need to see if there is an equivalent.

Thanks for the idea, will look for it, certainly the idea of pressurised can is good on its own as most sealant in a tube dried out after a while.

 

[Vinniec5]

Sorry i didn't know you were in Singapore but you could ask the parts dept at one of the bigger service centres or look for a shop that specializes in street racing I'll bet they know where to find it, if not here's a list of distributors that should be able to help you.



ARC Marine Pte. Ltd.
6, Tuas Avenue 9
Singapore 639171
Phone: 6862 6112
Fax: 6862 1027




Wah Lei Industrial Supply Co. Pte. Ltd.
12, Kian Teck Drive
Singapore 628829
Phone: 6265 0033
Fax: 6265 5369


Voss ( F.E ) Pte. Ltd.
Blk 803, King George's Avenue, #01-192
Singapore 200803
Phone: 6296 4992
Fax: 6298 2912




Unique Hardware Co. Pte. Ltd.
100 Woodlands Ind. Park E
Singapore 757837
Phone: 6748 8211
Fax: 6747 8026


Hong Teck Hin Hardware & Machinery Pte. Ltd.
265, Jalan Besar
Singapore 208938
Phone: 6294 3600
Fax: 6298 0821

 

[Tranworld]

Wow, thank you for the information, I will look for it today.

 

[Vinniec5]

Look for LOCTITE brand RTV Silicone in the pressurized can

 

[bshanahan14rulz]

I bet tape on the lens would help mask it off and make cleanup easier...

 

[Tranworld]

No, there is no pressurised can in Singapore

REF NOS : 1350609/Q/CL
Thank you for your inquiry. Please find our quote below.
1. LOCTITE 598 BLACK HIGH PERFORMANCE SILICONE GASKET MAKER - 300ML, P/N:25752 …… @S$40.00/btl (not spray type)

This is what I got after having specified SPRAY CAN type !

However I have worked out how to waterproof it by simply putting an O ring there and press fit the front lens back. Will do some pressure test today and let you all know. Remember that this is a cheap torch, it is not meant to be a diving torch so all I want is to improve it as much but as cheap as I can.

It has a surprisingly bright LED directly driven, with 3AA as its main power source, but which I have found a way to put in a 18650 instead. The LED is supposed to be 1W but is almost as bright as some of my other high end torches, it is already well heatsinked (with heat paste as well!).

I have plenty of 18650 coming out of unused laptop spare battery (never used, but laptop died, returned to company etc., my company used to supply me with a DELL laptop and 3 spares battery pack, of course the 3rd one rarely get used, if ever, when I returned the laptop they don't want any spare battery pack, so I kept them)

The body is made of good quality metal, with places or o rings, which I upgraded to good type, and just the front lens to seal off. It is meant to withstand rain, mud or even swimming pool but not much more than that.