Probably stupid multiple 18650 question

So, I have a Malkoff MD2 hi/lo turnkey. I love it to death, but the body is too short for me to comfortably carry it as it slips all the way into my pocket instead of sticking out of the top. I want to get a longer body (I think this one would work right?

Obviously since I will be using two 18650's I can't use a pair of flat tops. But would it be safe/ok to use a flat top on the battery adjacent to the head, and a button top for the bottom one? If the batteries were the same mAh and both charged and used in pairs, I was thinking it would be ok.

The part that might be better for the MD2 is the extenders either the single cr123 or the 18650 sized, I am not sure that the 2x 18650 solar force body would work with the MD2 head.

I'm not aware that anything fits a Malkoff head other than a Malkoff body.
You could use an MD4 body for two 18650s as long as you ensure the drop in is good for 7.40 volts.
Can you not use two button tops? It's generally accepted that for best practice you should use similar cells from the same manufacturer if running in series. Some go as far as using them from the same batch.
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I've been using AW flat top18650s in series for years without any connectivity issues. They have small protrusions on he negative contact.

You can also put a small neobium magnets in between the cells if they don't work. I wouldn't use two different cells. Just because they have the same mah doesn't mean they'll discharge at the same rate. Also I'd get the md4 body. I don't think the md2 head will fit on solarforce body. The m61 will work fine on 2x18650 and will give full brightness till cells are dead. In this case protected cells are recommended because those cells will not drop in brightness even when they're discharged two low

peter yetman said:

I'm not aware that anything fits a Malkoff head other than a Malkoff body.
You could use an MD4 body for two 18650s as long as you ensure the drop in is good for 7.40 volts.
Can you not use two button tops? It's generally accepted that for best practice you should use similar cells from the same manufacturer if running in series. Some go as far as using them from the same batch.
P

Click to expand...

I thought the Malkoff heads were made to be used on Surefire bodies and the threading was the same?

peter yetman said:

I'm not aware that anything fits a Malkoff head other than a Malkoff body.
You could use an MD4 body for two 18650s as long as you ensure the drop in is good for 7.40 volts.
Can you not use two button tops? It's generally accepted that for best practice you should use similar cells from the same manufacturer if running in series. Some go as far as using them from the same batch.
P

Click to expand...

I may have to do that, I just already have some flat tops and hate to see them be unusable.

vicv said:

You can also put a small neobium magnets in between the cells if they don't work. I wouldn't use two different cells. Just because they have the same mah doesn't mean they'll discharge at the same rate. Also I'd get the md4 body. I don't think the md2 head will fit on solarforce body. The m61 will work fine on 2x18650 and will give full brightness till cells are dead. In this case protected cells are recommended because those cells will not drop in brightness even when they're discharged two low

Click to expand...

Hmmm, good point. I wonder if I might need to just sell the MD2 and get the M91 head and MD4 body?

Balog said:

I thought the Malkoff heads were made to be used on Surefire bodies and the threading was the same?

Click to expand...

No. The drop in were made to fit surefire hosts. They designed the md2 to fit the drop ins even better. The drop in goes in the head not the body like in a surefire

Balog said:

I thought the Malkoff heads were made to be used on Surefire bodies and the threading was the same?

Click to expand...

The threading IS the same, but in the SF the drop in is rebated into the body, on the Malkoff it is flush with the end of the body. The retaining ring is anyway.

Balog said:

I may have to do that, I just already have some flat tops and hate to see them be unusable.

Click to expand...

If your Flat Tops have the nipples on the -ve end you can do it like Grizz says. Or use the magnets, you can fix them with some Loctite, AFTER positioning them to ensure conductivity, or place a blob of solder on the +ve ends to act as a Button Top.

Balog said:

Hmmm, good point. I wonder if I might need to just sell the MD2 and get the M91 head and MD4 body?

Click to expand...

You can never have too many Malkoffs.
Why not get the MD4, see how you get on and buy the extra parts later, then sell the other bits?
That is the beauty of the Malkoff System - it's modular.
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Balog said:

Hmmm, good point. I wonder if I might need to just sell the MD2 and get the M91 head and MD4 body?

Click to expand...

Know the m91 will be brighter. You can still use the m61. Same brightness but double the runtime and full regulation

Thanks everyone. I wish you could buy the M91 with the MD4 body as a turnkey instead of just with the MD3 then ordering a separate body.

Just Email Gene or Cathy and tell them what you want. They'll sort it, don't worry.
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