WM16B Draw Bar

Had to change the milling chuck for a drill chuck for the first time

The new Warco produced manual instructions are to loosen the draw bar cover by approximately three to four full turns and then to tap the head of the draw bar with a rubber mallet . Sound easy doesn't it .

Problem is the top of the draw bar is a 8mm square that projects only a couple of mm above the draw bar cover when it is tightened down. Unscrew the cover and the end of the draw bar is below the surface so nothing to hit,

Put brain cell in gear. Removed cap and draw bar. Skimmed 4mm from end of cap and similar amount from the collar below the 8mm square of the draw bar

. Putting it back together results in the 8mm square end of the draw now projecting above the cover. when screwed down . 8mm spanner can now turn the draw bar with the cover still firmly in place . Collar at the top of the draw bar now presses against the inside of the cover and breaks the taper

Brian .

Er, it's a captive draw bar, you don't need to hit it with a hammer. Just unscrew using the 8mm square and hold the spindle or chuck with another suitable spanner. Just undo, it will go stiff and with the application of a little more oomph it will pop the taper. Don't do it up too tight, only needs a light pinch to hold if the tapers are clean.

Has worked for my smaller WM14 for years.

John

Edited By Journeyman on 02/01/2021 16:38:44

John

I agree that the draw bar SHOULD be a captive design. The point I was trying to make that thanks to its design and manufacturing tolerances , as supplied it was not.. The bare 2mm projection of the 8mm square with its rounded edges together with the rounded edges of the supplied spanner made it impossible to grip the square. The WARCO instructions only serve to confuse the issue. Removing the cap would have given access to the top of the draw bar but releasing it "thee or four turns" as stated in the new glossy manual only shielded the top of the draw bar totally. The simple mods I made converted it to a workable system . The 8mm square now projects more than a spanners width above the cap allowing it to be rotated to break the MT3 taper.

Brian

Hi Brian, slightly misconstrued your OP, have got it now. Mine looked like this from new with the square nicely visible.

The cap has always been tightened right down and the draw-bar spins nice and freely with just a little vertical play. I must admit to not bothering to change the chuck often, for drilling I just use the almost permanently mounted ER25 chuck with suitable collet. Helps with headroom and doesn't take much longer to use than a drill chuck.

John

The drawbar square on my WM 16B protrudes a full 10mm, so no problem with the self ejection. Sounds as if the upper part of the drawbar could be wrongly dimensioned. A replacement isn't too hard to make, or perhaps just a thick washer between the drawbar and spindle might do the trick, but this would reduce the thread engagement with the MT arbour Incidentally I find that a 7/16" af hex.socket fits the square nicely, which speeds up tool changing by allowing the use of a ratchet.

Edited By Clive Brown 1 on 03/01/2021 11:43:56

Edited By SillyOldDuffer on 03/01/2021 11:52:08

iI guess I was a victim of Wun Hung Low quality control. ! Other that the draw bar issue I have found the 16B tp be excellent. I only have a 0.001" clock but that showed only a trace of movement when I checked the tramming.

I have added a thrust washer to the left hand end of the x axis screw , perhaps the lack of one is another example of careful assembly. and quill plate to give me a depth stop.

SWMBO considers it a great improvement over rmy previous mill, a VM . She says that it makes less noise than her sewing machine !

Brian

I used to use an Austin mini brake adjusting spanner when I had my WM16.

Mark P.

...Incidentally I find that a 7/16" af hex.socket fits the square nicely, which speeds up tool changing by allowing the use of a ratchet.

Same here with my WM16; have used socket with a 1/4 drive ratchet, 6" long handle, no need to apply 'ooomph' with any potential to kinetic energy transformer, & only tighten with the lightest of 'nips'

George.