Headstock Runout

[Ed Urban]

A friend gave me Fisch 90-100 Midi Lathe. He said its about 8 to 10 years old, and maybe he made a couple dozen pens on it. He said its a piece or crap, can't even drill a pen blank because there is so much runout on the headstock. I did my own test using my Nova Chuck with the universal pen jaws and my drill chuck that produce perfect results on my Jet mini-lathe. I mounted them on the Fisch and sure enough the holes were over sized and the pen tubes would fall through as opposed to a friction fit on the Jet. Any suggestions as to how to correct the problem?

[Mark Greenbaum]

Possibly the belt is too tight causing deflection of the main output shaft. Or the shaft is bent (that would require disassembly to determine and straighten). Or if there's any bearing noise - bad bearing. Get a dial indicator and hand turn it to see what the T.I.R. is (Total Indicator Runout). Those are just a couple of things I'd be looking for to start.

[Dennis Ford]

The over sized holes could have been caused by poor alignment between the head-stock and tail-stock. The first step in correcting the problem is identifying the problem. If it is run-out, you are probably looking at replacing either bearings or bearings and spindle (I doubt the lathe is worth replacing the spindle). If it is alignment, the fix may be inexpensive but will likely not be easy unless the lathe is twisted slightly due to how it is mounted; that would be easy to fix.

[Brice Rogers]

I think that Mark and Dennis have given you some good advice.

However, I would like to add a bit to Mark's comment. You should try to measure TIR of the spindle by itself and then with the chuck mounted. If there is something funky with the threads, material on the "register" or seat of the spindle, it can throw off the chuck.

I was using my new grizzly chuck (T10811). I was holding something with the pin jaws (probably what I'd hold a pen with. I noticed about 0.010 TIR. I isolated the runout to a single jaw and found the with a shim of about 0.010" polyethylene (thickness of jug of water container), it miraculously went to near zero.

Some other things that could come into play is the drill bit, if the other things check out. On a typical drill bit, it is critical that each side of the cutting tip be exactly the same width. I have had some Harbor Freight bits that were visibly bad and would drill 0.015 or more oversize. Some good ways to minimize this (besides grinding the drill correctly) is to mark the exact center of the thing you are drilling, use a punch to dent the wood (significantly), and use a small stubby drill to start the hole (like a metal lathe centering drill) and then a large drill to slightly enlarge the hole. If you try to drill the hole with a single drill and in a single operation, it is very easy for the drill to be pushed off center by the grain of the wood.

[Brice Rogers]

To measure runout, it is easiest to use a dial indicator. They can be bought for under $20. If you don't have a magnetic base, you may need to figure out some way to rigidly hold it.

But a poor man's alternative would be to place your tool rest very close to the spindle or the chuck - - ideally, make it close enough that a piece of typing paper (about 0.003" or so) just rubs at the closest point. Then rotate the spindle to the point where there is the largest gap. Measure the space with a auto feeler gauge or multiple sheets of paper. You can actually tell a lot optically - - that is, by just eyeballing it with a sheet of white paper behind it. It will at least give you some sort of estimate at the amount of runout.

It is possible to have an otherwise good scroll chuck whose runout changes depending on whether the jaws are close in or far out. Also, if you are measuring runout with the chuck on, have it clamping down on something the same diameter as with which you were having problems. If it requires a key rather than a tommy bar, some people will moderately tighten one key spot and then (if there are two places) the other one as this will help to center the scroll a bit.

For applications other than making pens, a bit of runout isn't a big deal.

[Mark Greenbaum]

These are all great suggestions for detecting the real problem. The tailstock may be off center. The chuck may not be running true to center (not seated correctly or weird threads). Probably something very simple.

[Thom Sturgill]

Since you used a known good scroll chuck, jacobs chuck, and drill bit those can be eliminated, but used to help determine the problem. A dial indicator would be your best bet. Measure both at the face of the chuck (perpendicular to the bed) and at the face where the chuck seats (parallel to the bed). Also check that the bed is true. That's easiest with a set of 'winding sticks'. They will show any twist quickly regardless of level or lack of level. Checking that the points of the live and drive centers align when touching does not mean they align when separated. Use the drill bit in the jacobs chuck and check it against a drive center. So if it is off more than when the live center and drive center are touching.

[Dan Masshardt]

If you chucked up a piece of wood in the chuck on your good lathe and trued it up and then transferred the chuck to the other lathe, wouldn't the piece be out of true if the problem is in the headstock?

[Geoff Whaling]

A friend gave me Fisch 90-100 Midi Lathe. ...... He said its a piece or crap, can't even drill a pen blank because there is so much runout on the headstock.

Nice friend - giving you a source of frustration. The Fisch looks very similar to the Woodfast m305 midi lathe which has quite a good reputation here, but that does not mean they are the same lathe with identical manufacturing, and parts specifications or quality control.


Since you used a known good scroll chuck, jacobs chuck, and drill bit those can be eliminated, but used to help determine the problem. ......

Drilling operations will quickly highlight any deficiencies in the wood lathe, accessories and your technique creating oversize or “non-axial” holes, etc.

There have been some good points mentioned. Thom's comments re elimination of the chuck, jacobs chuck and drill bit are partly true.

Each time we install these on the lathe and position then lock down the tail stock there are sources of error which can cause misalignment - debris in the spindle threads or morse taper socket etc. One major cause of misalignment is a poorly mounted & set up lathe which creates lathe bed twist. For portable lathes this may vary each time the lathe is re-positioned.
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The design of most (all?) wood lathes do not make any provision to correct minor misalignment issues of the head & tail stocks.

(Ignoring lathe bed issues, twist etc) To drill holes accurately in pen blanks or spin top blanks the lathe must satisfy a couple of conditions, the axis of both the head stock spindle and the tail stock MT socket must be parallel, and co-linear i.e. aligned vertically & horizontally; the spindle threads concentric to the spindle axis; similarly the MT socket concentric to the tail stock quill; then the alignment boss on the tail stock parallel to the quill; then hopefully there is not excessive play between the bed ways slot and the tail stock boss etc.

Ideally these would all be manufactured perfectly but they are not, they are manufactured within “acceptable tolerances” to save on manufacturing costs, the same applies to chucks, jaws sets, jacobs chucks, live centers etc. Occasionally a lemon will sneak through.

I drill lots of holes in pen blanks and concentric holes to install spindles into laminated spin top discs. All lathes I have used have some misalignment error, some are terrible and imo obviously lemons delivered through poor manufacturing and poor quality control. I have learned to eliminate some sources of error but only minimize the effects of others.

Some practical tricks I have found that work for me when drilling on the lathe,



Square up the blank face to be drilled if possible.
Check the centre heights of a blank with a fine accurately marked centre hole and a live centre in the tailstock. Height misalignment can in some instances be corrected through machining or shimming.
Checking co-linearity is more difficult but setting up and drilling a few waste blanks to optimize each setup before using quality blanks helps.
Experiment & find which alignment position of the tailstock works best, by setting the boss on the tailstock hard against the near or far bed rail, or skewed fore or aft etc.
Mark / create a decent sized pilot centre, 2/3 rds drill dia, with the long point of a skew – this eliminates Jacobs chuck issues.
Do not drill pilot holes. Drill with the final size bit in one pass. Smaller diameter pilot holes and drilling in stages of increasing diameter tend to drift more due to wood grain issues.
Commence the hole while very slowly advancing the quill, then increase the drill feed rate once the drill point is well seated.


Seemingly trivial matters such as the blank face not being square to the drill axis can deflect the alignment of an advancing drill bit. I also prefer a collett chuck over both a conventional four jaw chuck with pin jaws (& a jacobs chuck) to hold pen blanks and also to hold drill bits.

No guarantees but it will give you the best results attainable with that gear. When we make things on a wood lathe we also manufacture within “acceptable tolerances.” Working out what is acceptable and practical with the gear we have is part of the game.

If you want consistent high accuracy for drilling operations then perhaps a quality metal lathe is the solution.

[Brice Rogers]

Geoff, very good advice. Sometimes when I'm drilling and can't afford to let the drill wander, I'll use a home made steady rest. I've also used my metal lathe a couple of times as well (as you suggested)

[Geoff Whaling]

Geoff, very good advice. Sometimes when I'm drilling and can't afford to let the drill wander, I'll use a home made steady rest. I've also used my metal lathe a couple of times as well (as you suggested)

I well & truly understand the aggravation this issue causes as I have dozens of laminated spin top blanks with off center holes. I have a considerable amount of time invested into them & they are just sitting there waiting for me to turn, rather than drill, a new accurately centered spindle hole. I even purchased a new Vicmarc VL150 lathe to overcome many of the issues. Its the best wood lathe I have used so far for drilling accurately, but still not as accurate as I would like. Though many of the issues are related to the drill bit wandering in the wood grain.

A small metal lathe is on the wish list, and after watching Bill Ooms demo his highly accurate wood turning on a small metal lathe at Turnfest I'm convinced that they are the way to go, but even the budget metal lathes have issues.

[Ed Sandle]

You need to find out if your lathe has run out first. You need to do that without the chuck on the lathe. Lathe run out is measured from the flat face on the spindle. One thousandth run out there, would be about 3-4 thousandths at the outer edge of a chuck. Lathe run out will be either the bearings, or the spindle its self. Either one, probably not worth fixing on a cheap lathe.