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Drilling tailstock for Jet BD-920N?

Posted: Mon Mar 24, 2008 11:59 am
by ASB
I jsut purchased a used Jet BD-920N lathe and have spent the past few days playing with it. I have found one very serious drawback. Not sure if this is typical of the metal lathes, but the wood lathe I had before was a true piece of crap but I could turn the wheel on the tailstock and the thing would move like 8-10 inches, well on the new toy it only moves about 1\2 inch. Does anyone else have this lathe, and if so, do you do any of your drilling on it, and if so, how? I have been searching for accessories and can't seem to find anything. I guess what I want is the tailstock off my POS lathe on my new Jet, but of course that won't work. It came with the Jacob's chuck, but when I loosen the nut that keeps the tailstock locked in place just enough to move it it wobbles all over the place. I've tried putting the tailstock inside the apron, but when it's loose enough to move it wobbles like crazy. I'm drilling at 130 rpm so really don't think it's going too fast, just not stable.

On the positive side this thing is freakin' awesome for stem work, pens, inlays, extensions, whatever else.

Posted: Mon Mar 24, 2008 3:51 pm
by kkendall
The spec shows the tailstock travel to be 1-9/16".

Also - take a look here. You may find some useful tips:
http://groups.yahoo.com/group/9x20Lathe

Posted: Mon Mar 24, 2008 10:39 pm
by JHowell
That doesn't sound right. The tail stock should ride on one V-way, so even if it's not locked down you can just slide it on the ways and still track straight. You might make sure that the adjustment screws that center the tail stock are tight. Also make sure that the tail stock is centered on the spindle. Maybe post a picture or two. Not much can be done about the quill travel, but the wobbling when locked down doesn't sound like a typical metal lathe problem.

Posted: Mon Mar 24, 2008 11:23 pm
by RadDavis
It should travle more than a half inch. Mine goes about 1 1/2 inches or so.

I use it to get most holes going as far as it will travel and then just loosen it up and push the tail stock into whatever I'm drilling from there on.

It shouldn't wobble.

Rad

Posted: Tue Mar 25, 2008 9:59 am
by ASB
It only wobbles when I loosen the nut that holds it tight when I am attempting to slide it in further. I start with the bit just barely not touching the briar (and tailstock locked down) and power up the lathe then feed the bit as far as it goes with the wheel, loosen nut, slide up a bit (this is when it wobbles, chatters, gets out of line), retighten nut, then advance the bit again with the wheel.

The tailstock and headstock line up perfectly when TS is tightened down.

Maybe I ought to stop the briar from turning while I am advancing the bit manually (with the nut loosened) as this is when it chatters?

I also found a really nifty attachment surfing the net yesterday evening called the Millmate tailstock drill press at http://www.millmate.com/Tailstock%20Drill%20Press.htm but I think I can work around the problem rather than spend another $400 this week.

Posted: Tue Mar 25, 2008 10:40 am
by kkendall
ASB wrote:I also found a really nifty attachment surfing the net yesterday evening called the Millmate tailstock drill press at http://www.millmate.com/Tailstock%20Drill%20Press.htm but I think I can work around the problem rather than spend another $400 this week.
That nifty gizmo won't do you any good. They only come with a MT-3 and MT-4 shanks. The Jet lathe you have has a Morse Taper #2 spindle in the tailstock.

Another thing that would have probably been an issue is the amount of real estate that thing takes up. By the time you get a block of briar in your chuck, and add that thing, you'll probably be left with enough room for a 3" drill (I really don't know exactly how much would be left, but I know you'd be getting close!)

Sounds like there is a shim missing in the tailstock gibs (or the gibs need adjusting). There shouldn't be all that much wobble when the gibs are loosened.

Posted: Tue Mar 25, 2008 5:15 pm
by JHowell
There aren't any gibs in the tail stock, the clamp from below holds it down onto one flat and one V-way. The center adjust screws could be loose. Sounds like the wobble happens drilling the chamber, and that could have to do with the bit. If it cuts more on one side than the other, it needs to be locked down tight and it might wobble and chatter even then. Drilling with a normal twist drill should not cause any wobble, especially if you've started the hole on center.

One thing I've found that helps drilling is to start EVERY hole with a center drill. A center drill won't wander because it's very stiff relative to the small point that starts the hole. A twist drill will almost always wander before it starts. Even if it seems like you're drilling straight onto a level surface, using a center drill to start, without exception, will eliminate that percentage of holes that start off center.

Posted: Tue Mar 25, 2008 7:34 pm
by KurtHuhn
JHowell wrote:One thing I've found that helps drilling is to start EVERY hole with a center drill. A center drill won't wander because it's very stiff relative to the small point that starts the hole. A twist drill will almost always wander before it starts. Even if it seems like you're drilling straight onto a level surface, using a center drill to start, without exception, will eliminate that percentage of holes that start off center.
I started doing this at Jack's suggestion a while back, and it works like a charm!

Posted: Tue Mar 25, 2008 8:07 pm
by dougk52
I do a lot of metal turning. When drilling always use a center drill it will keep the bill drill true in the work piece. Brier is pretty darn hard stuff so a center drill is the way to go.

Posted: Tue Mar 25, 2008 8:18 pm
by KurtHuhn
KurtHuhn wrote:I started doing this at Jack's suggestion a while back, and it works like a charm!
Jeez, that really comes across as a Sunday morning infomercial, doesn't it. :oops:

Posted: Tue Mar 25, 2008 10:29 pm
by bscofield
KurtHuhn wrote:
KurtHuhn wrote:I started doing this at Jack's suggestion a while back, and it works like a charm!
Jeez, that really comes across as a Sunday morning infomercial, doesn't it. :oops:
i stood up and clapped like i was really impressed.

Posted: Wed Mar 26, 2008 2:38 am
by Frank
KurtHuhn wrote:
KurtHuhn wrote:I started doing this at Jack's suggestion a while back, and it works like a charm!
Jeez, that really comes across as a Sunday morning infomercial, doesn't it. :oops:
I want to buy one for myself, plus another one for the in-laws. Where do I phone in my Credit Card details? Does it come with a lifetime guarantee? :twisted:

Posted: Wed Mar 26, 2008 5:32 am
by KurtHuhn
Yes! All that and more! But supplies are limited, so have you're credit card readdy and call now! Operators are standing by! And as a special bonus, if you call in the next 5 minutes, we'll ship your order for free!

Posted: Wed Mar 26, 2008 3:28 pm
by ASB
Okay, after looking over the exploded part detail of the tailstock I realized there was something amiss (I was looking for the gibs and something else just clicked). There was something out of line that was keeping the quill from going back in all the way, monkeyed around with it last night and got it fixed. I got two blocks drilled and several stems fitted in about 4 hours (before I got this lathe that all would have taken me about 12 hours and the stems still would be very ugly and not very tight fitting). Thanks for all the help! I do always start with a center hole started except on the tobacco chamber, I am using Lamb drill bits there and they don't seem to drift much.