MagLite tapping

gallonoffuel

Enlightened
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Mar 11, 2008
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Northern MD
I've searched for a while and came up with some information, but not exactly what I'm looking for. I'm wondering if anyone has successfully cut down a D cell MagLite body and re-tapped with an actual tap instead of doing it on a lathe. I'd like to make a 1D. The other option (short of sending it out to a machinist) is to cut it into 3 sections and have my buddy TIG it up at work. My aluminum MIG work isn't that spectacular and would probably require a lot of cleaning up when I was done.

Thanks guys!

EDIT: After some more research, it appears that taps of this size are in the $80-100 range? If it actually works, it might be work buying anyway because I doubt this will be my first and last mod of this type.
 
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I say this as my cut down 4 D M@g is in the chuck to be rethreaded, if you have the funds, go for it. It would be a high interest item. Most of us are advanced hobbyists with all sorts of fun toys to make or modify other toys. It would take so much pressure off of all of us "non" machinists if there was a tap we could just simply use on our reduced size M@gs instead of sweating bullets trying to rethread.

If you decide to proceed with this please, please, please keep us up to date on how it worked to include pictures.

Bob E.
 
I say this as my cut down 4 D M@g is in the chuck to be rethreaded, if you have the funds, go for it. It would be a high interest item. Most of us are advanced hobbyists with all sorts of fun toys to make or modify other toys. It would take so much pressure off of all of us "non" machinists if there was a tap we could just simply use on our reduced size M@gs instead of sweating bullets trying to rethread.

If you decide to proceed with this please, please, please keep us up to date on how it worked to include pictures.

Bob E.

It would be almost impossible to keep straight.
 
You can't really use just a tap. The tail end of a Maglite has a 1.450 diameter oring surface for the first .150 Then it has approx .500 of threads.

The internal bore has to be 1.390 before single point threading. So unless they sell a drill bit that size I doubt it's possible. Then even if you get a drill bit and tap I highly doubt a hand drill would work safely.

Mac
 
Sorry to hijack, but I've found zero info on this through searching and contacting mag...

Anybody know what tap to use to clean up threads on a minimag?
 
I've seen a way this can be done but it's very dangerous and I don't recommend it. That said let me post a link.

LINK

If you scroll down the page you'll understand what I mean. Again, this is not a suggestion I just thought this was interesting.

You can't really use just a tap. The tail end of a Maglite has a 1.450 diameter oring surface for the first .150 Then it has approx .500 of threads.

The internal bore has to be 1.390 before single point threading. So unless they sell a drill bit that size I doubt it's possible. Then even if you get a drill bit and tap I highly doubt a hand drill would work safely.

Mac
 
I've seen a way this can be done but it's very dangerous and I don't recommend it. That said let me post a link.

LINK

If you scroll down the page you'll understand what I mean. Again, this is not a suggestion I just thought this was interesting.

:eek: :eeksign:
 
Eek indeed. I do have access to a lathe (its in my garage) but I've never used it and I dont think i'd be able to cut threads on it. However, I could possibly use it by cutting the front and rear sections of the body where I want, and turning down the inside of one end and the outside of the other end, making a slip fit. I'd then TIG weld in a few spots and grind smooth.

Or I could just pony up and have someone here cut it for me. But there's just something about paying people to do my work that I cant stand. :grin2:
 
It would be almost impossible to keep straight.
A tap holder (or large Jacobs Super Chuck) is the easiest way to hold a tap in the lathe tailstock. For an easy threading material like aluminum, the Super Chuck provides plenty of grip.

Bore the barrel ID to size & put the lathe in slow back gear (30 or 40 rpm works well). Lube the bore & the tap with your favorite tap lube. MOST IMPORTANT - don't lock the tailstock, but use hand pressure to push the tailstock/tap into the bore as the spindle is slowly turning. Thread to depth (a white mark on the top of the tap is a good depth indicator) and it's all done:D
 
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A tap holder (or large Jacobs Super Chuck) is the easiest way to hold a tap in the lathe tailstock. For an easy threading material like aluminum, the Super Chuck provides plenty of grip.

Bore the barrel ID to size & put the lathe in slow back gear (30 or 40 rpm works well). Lube the bore & the tap with your favorite tap lube. MOST IMPORTANT - don't lock the tailstock, but use hand pressure to push the tailstock/tap into the bore as the spindle is slowly turning. Thread to depth (a white mark on the top of the tap is a good depth indicator) and it's all done:D

With a lathe there's no problem, without one is what I was alluding to.
 
I don't know what the back end size of a tap to thread the inside of a Mag 'D' light, but I would guess that it is going to be bigger than what will fit in the tailstock of the lathe.( I could be wrong on this ) I personally would not attempt to use a tap over 3/4 inch, even in a lathe.

A single point threading tool in a lathe is the best way to go.

If you have a lathe in the garage, and it is a metal cutting lathe, I would suggest that you learn how to use it. Most metal lathes have the ability to cut threads.

As to welding pieces together, I would not do that either.

If you are interested in doing just a few lights, there are people here that can do a profesional job cutting and rethreading at a reasonable cost.
 
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I would guess that it is going to be bigger than what will fit in the tailstock of the lathe.
Almost all hand taps have a four-flat end shank. To make a tap to tailstock adapter, you need only a Morse taper shank that matches your lathe tailstock - bore to fit the tap shank, install two allen setscrews to hit two flats on the shank & it's done.

Tailstock tapping is easy, both for machine threads & pipe threads. I've run a 3" NPT in a tailstock, and run that same tap in a Morse MorSpeed radial drill (both had #5MT spindles). The tailstock is always better for round parts, but either will work.

A single point threading tool in a lathe is the best way to go.
A single point tool works OK, as does a solid carbide threadform tool.
 
Tailstock tapping is easy, both for machine threads & pipe threads. I've run a 3" NPT in a tailstock, and run that same tap in a Morse MorSpeed radial drill (both had #5MT spindles). The tailstock is always better for round parts, but either will work.

.

I have run large taps when I worked in a machine shop and we had some really large lathes, Most home setups, from what I have seen here, are not that large.
 
Our lathe is fairly large, and while I don't have the specs, my father uses it to turn down hinge pins and things for a CAT 933 loader and a Deere backhoe that are hard to get or expensive. I've never used it before though. I'd like to become proficient at using it, and perhaps this is the project with which to do that.

will, is there any reason besides aesthetics why you would be opposed to welding the pieces together?

I know my proposals are not the 'best' options, and I understand there are folks here that can do a professional job using the proper tools. I'm just exploring options that might be available for the do-it-yourselfer without all the right equipment. Thanks for everyone's input!
 
The welding would be more work than just cutting it down and re threading. also - there is the finished look..
 
is there any reason besides aesthetics why you would be opposed to welding the pieces together?
You have to remove all the anodizing before welding, which is most easily done with a light skim cut on both sides of the area to be welded. Then you have to decide if you're going to grind/turn the weld down - either will look strange.

Threading is the best option.
 
I have also done a lot of work with press fitting tubing together.

basically

bore out the inside diameter to 1/2 the wall thickness, turn down the part to be pressed in to .0003 - .0005 larger than the bore, The length to be bored and turned down should be at least 1/2 the diameter of the tube. for example - a 2 inch tube should have the length at least 1 inch. This will be neater than welding.

caution - this will result in the weakest option, but it will work. To be honest, doing all this work is much more difficult that just cutting it down and re threading.
 
While I was trying my first attempt at rethreading one of my M@gs, my neighbor (an accomplished sheetmetal guy with moderate metal working skill too) made a good suggestion as others here have done.

Do the press fit thing and use the best Loctite stuff you can find to keep it in place. He thought it was a green color instead of the blue or red most of us have seen for use on the car. I believe he said on the package it says basically after it drys, you will have to use a chisel to get it apart. So don't use it on anything you want to take apart.

After my first rethreading attempt (OK, it worked but was not pretty) I am inclinded to maybe give this a shot, but I think I may know what to do next time when rethreading......something to do with which way you move the tool, in or out while you thread. For you novice people, it makes all the difference in the world.

Bob E.
 
While I was trying my first attempt at rethreading one of my M@gs, my neighbor (an accomplished sheetmetal guy with moderate metal working skill too) made a good suggestion as others here have done.

Do the press fit thing and use the best Loctite stuff you can find to keep it in place. He thought it was a green color instead of the blue or red most of us have seen for use on the car. I believe he said on the package it says basically after it drys, you will have to use a chisel to get it apart. So don't use it on anything you want to take apart.

After my first rethreading attempt (OK, it worked but was not pretty) I am inclinded to maybe give this a shot, but I think I may know what to do next time when rethreading......something to do with which way you move the tool, in or out while you thread. For you novice people, it makes all the difference in the world.

Bob E.

Thought this might be some help Bob.

http://www.frappausa.com/PDF/Articles/Machining/Engine Lathe/150235.pdf
 

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