10k spindle question

Over the years this question must have been asked many times, but the search function did not serve me well-or more likely, I asked the wrong question.

I have a late model 10k without any headstock mods. Lathe new to me.

A. Am I correct with the following?

1. The 10K spindle general taper is a 3MT.

2. The 6K collets fit without any sleeve or adapter. They just use a 6K size drawbar and the small front mounted "tit" to keep the collets from spinning.

3. The 3C sleeve (adapter?) has a 3MT on the outside of the unit.

B. I also have some 3C collets, a 3C sleeve (adapter?) and a 3C drawbar that is too short.

1. Does anyone know what length I need for the 3C drawbar in the SB 10K spindle to use my 3C collets? I have some 3C collet sizes that I do not have in the 6K collet size so I would like to use both sets of collets.

Lots of items, but I found a forum entry of 15years ago that left me confused.
Everything seems to fit for what I asked above, but I don't want to get anything jammed up if I am wrong.

Dan

6K large diameter is 1.160" - considerably larger than big end of #3 taper

The 10K is weird...as Mr. Oder noted the mouth of the spindle is way bigger than MT3....however it will still accept a MT3 to 3C adapter....not sure how wise it is to do so, as there isn't much engagement.

Ok. Thanks for the confirmation.
The 3MT seems to fit correctly, but there seems to be max confusion on the forum about the taper in a 10k lathe. I just needed to be sure.
I'll spend some time measuring the 3C drawbar.
Dan

Captain Dan

Type the same question or keywords into your main search engine to search any subject on P.M.
Google / Bing or whatever. You will get a lot more hits that bring you right back to those old Practical Machinist posts your looking for. It works for me. The forums search engine is not that productive.
Forum member Thermite has a good way of explaining why. I wont try to translate.

As stated above, the 10K spindle does accept a 3MT taper, but the first 1/2" of the spindle taper is steeper to accommodate the front taper of the 6K collet and acts as the closer.
The 3C nose piece/closer fits in the 10K spindle and the 9" (3C) draw bar works fine with this set up. I have a full set of 3C's, along with a set of 6K's (and 10K draw bar) and do use both with my 10K machine.
I Can measure the draw bar if you wish, but it is a standard 9" (hand wheel) version.
CWC(4)

Thanks, I forgot to mention that I have standard hand wheel drawbars.
Dan

I have a 10k. It came with a set of 3AT collets but the drawbar was for a Logan. I found a 3AT to 3MT taper adapter on ebay and it was a simple matter to modify the drawbar. Works great. My only complaint is that the knockout nut (AKA thread protector) is larger than the edge of the collets so it cant be used to knock out the collet. Have to do it the old fashioned way from behind.