Loose focus on [old] sci-fi 445nm 1W

[clansley]

Having just obtained my highest power laser to date (1W), I was a bit worried by a loose focus adapter as it can easily move from a non-reflective surface to a reflective one without moving the host!

From searching the forums I gather I should use 'Teflon tape' on the threads. Looking at Thread seal tape - Wikipedia, the free encyclopedia it seems there is some confusion over the term 'Teflon tape' - so I just wanted to be doubly sure that using PTFE tape (the tape plumbers use) is the right thing to do.

 

[Livinloud]

Re: Loose focus on sci-fi 445nm 1W

Yes the white tape normally found in a blue and white holder at any plumbing store, home depot, wal mart or even dollar store. Just make sure its not folded around by the lens or the beam will melt it

 

[clansley]

Re: Loose focus on sci-fi 445nm 1W

Yes the white tape normally found in a blue and white holder at any plumbing store, home depot, wal mart or even dollar store. Just make sure its not folded around by the lens or the beam will melt it

Cheers mate!

Update: tape now added and it's now perfect!

 

[Livinloud]

Re: Loose focus on sci-fi 445nm 1W

I use it on all my lens, gets rid of that little wobble and helps keep the lens from adjusting itself :beer:

 

[DTR]

Re: Loose focus on sci-fi 445nm 1W

Yep it will work good but suggest you only put it on the top 1/3 of the threads so that it just starts to thread into the module when you are near focus. If it is lower than that over time bits can fray and work their way down into the module. If any gets on the diode window it can damage the diode.:beer:

 

[clansley]

Re: Loose focus on sci-fi 445nm 1W

Yep it will work good but suggest you only put it on the top 1/3 of the threads so that it just starts to thread into the module when you are near focus. If it is lower than that over time bits can fray and work their way down into the module. If any gets on the diode window it can damage the diode.:beer:

The trouble is it wouldn't help me if I only put it on the top 1/3; Infinite focus is when I have it unscrewed by 4mm and it's very loose (the whole thread is only 8mm long). But I guess your message is to keep as much of the bottom clear as possible.

 

[BowtieGuy]

Re: Loose focus on sci-fi 445nm 1W

Are you using any kind of spring (internal/external) to help keep pressure on the lens barrel? Not sure if you're using one of the standard focusing adapters, or one of the custom ones which are much larger, and heavier.
I've heard of some people having to use a heavier spring when a large custom focus adapter is used.

 

[3Pig]

Re: Loose focus on sci-fi 445nm 1W

I've got an external spring on my 445, it sure makes focusing easier but I still get the same wiggle. Go for the plumbers tape

 

[clansley]

Re: Loose focus on sci-fi 445nm 1W

Are you using any kind of spring (internal/external) to help keep pressure on the lens barrel?

It has a large focus adapter.
There is a 14mm long (weak) spring behind the focusing barrel.

 

[DTR]

Re: Loose focus on sci-fi 445nm 1W

The trouble is it wouldn't help me if I only put it on the top 1/3; Infinite focus is when I have it unscrewed by 4mm and it's very loose (the whole thread is only 8mm long). But I guess your message is to keep as much of the bottom clear as possible.

Yep.:beer:

 

[Thejoker301]

Re: Loose focus on sci-fi 445nm 1W

Hi ,

I send it with springs I get from DTR. They usually work just fine.

But if you really want to get a more stable adapter just get an external spring. Or put Teflon like DTR advised.

Enjoy your laser , and if you need anything else let me know. Next time , you can just email me first I usually reply quickly to emails.

:beer:

 

[clansley]

Re: Loose focus on sci-fi 445nm 1W

Hi ,

I send it with springs I get from DTR. They usually work just fine.

But if you really want to get a more stable adapter just get an external spring. Or put Teflon like DTR advised.

Enjoy your laser , and if you need anything else let me know. Next time , you can just email me first I usually reply quickly to emails.

:beer:

Hi!

I would have emailed you if I had got it from you new, but as I got it second hand from "SN P", and it clearly didn't bother him so I thought I must be fussy and it might be wrong to contact you.

I will use teflon tape for now, but will also see if I can source an external spring and see how that goes too. :beer:

[Added "old" to original post, although I have no idea how old it is!]

 

[Pi R Squared]

I am using external springs from SL Accessories on 4 of my lasers and they work great, but the tape is cheaper. US customers can find them here: Accessories

 

[10fenny]

just make sure its not the liquid teflon tape. I have some at work for automotive and its pretty nasty stuff to be putting anywhere near a laser. You might hafta re-apply it every now and then too. teflon tape is made as pipe thread sealant so it not going to take being screwed in and out all the time.
I just had to do this to one of my lasers last week, for it was too easy to be bumped out of focus.