# how should I bore a SF 9p to 18mm?



## soupdragon (Jun 2, 2006)

It would be nice to run 18650 cells in the SF 9p body my question is how should I go about this. 

I dont have a lathe and would be using a drill and a vice

I can only find 18mm hss bits in the UK so would prob end up using some sandpaper and a dowel to get it slightly larger than 18mm 

I realise I'd need to leave a lip on the lamp end of the body for the negative spring to make contact

Is this gonna work or am I gonna end up with a mess and an unusable 9p body

Ta in advance


----------



## sandworm (Jun 2, 2006)

I bored out an inova xo3 to fit the 18650 and it works fine. I used a sanding cylinder and a dremel, although if you find a dowel that fits right and coat it with sandpaper you may make less of a mess than I did. One warning when you're fitting is to not force the battery in if it's a protected cell. The metal ribbon connecting the positive to the protection circuit rubbed through the shrinkwrap on mine and this can cause a bad short on the 9p. 



soupdragon said:


> It would be nice to run 18650 cells in the SF 9p body my question is how should I go about this.
> 
> I dont have a lathe and would be using a drill and a vice
> 
> ...


----------



## Protaeus (Jun 2, 2006)

When I bored out my m4 to accept 18650's I used:
An expanding hand reamer 17.75-18.25mm
An adjustable power drill
WD40.

You can also use the hand reamer by hand but its painful and takes forever to do.

To use the power drill you will need two people.

Set the hand reamer to a diameter which only just starts scraping the edges. Spray the inside of the torch with some WD40
Set the power drill to a high torque, low speed setting
Get one person to hold the torch (with gloves) while the other person uses the drill.
Keep repeating these steps, progressively expanding the reamer and applying wd40 after every go.

If you feel unsure about using a power drill, go by hand. This takes longer, but is almost fault proof.

The good thing about the wd40 is that it gives you a mirror finish.

edit: I bought my hand reamer used from the UK for about 10 pounds including shipping so you shouldnt have any problems finding one. Reaming is much more accurate than drilling and provides a rounder, smoother finish, not to mention that it is safer than a drill.


----------



## DBC (Jun 3, 2006)

This all sounds good but aren't there disadvatages to reaming?


----------



## wquiles (Jun 3, 2006)

DBC said:


> This all sounds good but aren't there disadvatages to reaming?


If you go too far, you will get way too thin right under the o-ring groove (on the tailcap side of the tube) and the whole tail could fall off and/or break easily because it is now too thin/weak  

Will


----------



## vortechs (Jun 3, 2006)

Protaeus said:


> When I bored out my m4 to accept 18650's I used:
> An expanding hand reamer 17.75-18.25mm
> 
> edit: I bought my hand reamer used from the UK for about 10 pounds including shipping so you shouldnt have any problems finding one. Reaming is much more accurate than drilling and provides a rounder, smoother finish, not to mention that it is safer than a drill.


 

Does anyone have advice on where to get a hand reamer of the appropriate size in the USA (and some instruction in how to use it)? Is this something that Home Depot or Lowes would carry or is it a mail-order type item? 

I'm interested in boring out a 'Golston 7W' for use with 18650 cells.


----------



## highorder (Jun 3, 2006)

FIRST:


> To use the power drill you will need two people.
> 
> Set the hand reamer to a diameter which only just starts scraping the edges. Spray the inside of the torch with some WD40
> Set the power drill to a high torque, low speed setting
> ...





THIS IS THE MOST UNSAFE THING I HAVE EVER HEARD ON CPF!

hands are NOT proper workholding equipment!

as far as tools, drills ALWAYS make a hole that is slightly larger than listed size. for the appropriate tools, look no further than http://www.mcmaster.com/ as for WD-40, its NOT a cutting fluid. you would be better off with any oil in the kitchen than WD-40.

I suggest you open the yellow pages and find a local machine shop that will help you out.


----------



## Protaeus (Jun 4, 2006)

No, its not the safest thing in the world, but I was comfortable with it and as I said, if you dont feel right about using the power drill, go by hand.

As it happened though, I would have done more damage to my hands doing it by hand. 

If you dont like it, dont use it. Im just telling him what I did and what my results were. Acoording to my own observation, WD-40 made a wonderful cutting fluid, allowing for a smoother cut and a finer finish.

I simply dont have the money to buy a lathe and I dont have any machine shops nearby. 

As for it being the most dangerous thing ever on CPF - I've seen people exposed to much worse than that. Using magnets as contacts for high energy 18650 cells sealed inside the body of a maglite is just one of them.


----------



## brunt_sp (Jun 30, 2006)

Great advice everyone. I'm thinking of doing the same with my 9P. I intend to also bore out an A19 extender to accept 2 X 18650s. Add a KT2 head and MN21 lamp for 500 lumens ! Any thoughts ?


----------



## scott.cr (Jun 30, 2006)

As Protaeus has said, WD-40 would be an appropriate cutting fluid for aluminum, no matter which method you choose to cut it.

However I should mention this: Does the convenience of doing it yourself outweight the inconvenience of potentially wrecking the light?

If it was lathe-bored it would be very easy to retain the lamp's negative contact. Not so with the reamer.

If you do however choose to ream it I can offer the following advice: Withdraw the reamer frequently and clear it of chips. The cutting flutes are straight, not twisted like a twist drill, and will not automatically evacuate chips like a twist drill. The chips will cause a major malfunction as far as surface finish and if allowed to build up sufficiently, can cause enough friction to break the reamer.


----------



## Morelite (Jun 30, 2006)

If you still need the 9P body bored, PM me. I have a lathe and can do it for you.


----------

