drawbar question - help needed from fellow BF25 owners

[Henk]

Hi all,

Last Friday I purchased a BF25 L mill (http://www.buitelaar.nl/comasy/templates/product.aspx?contentid=237&productid=3620), it is sold under various names where mostly BF25 is in the name (e.g optimum / weiss). BTW, it is not obvious what the difference to the BF20 is (other than motor power).

After getting it into my garage, I noticed that the drawbar turns very unwillingly. If I try very hard I can almost turn it by hand - by far not freely.

Now my questions are :
1) After removing any tooling (MT3) from the spindle, I thought the drawbar should be able to rotate freely. Do I understand correctly?

2) I failed to understand how I could remove the drawbar in order to check for a bent drawbar. Any fellow BF 25 (or likewise) owner who could give me a hint?

Any help is greatly appreciated.

Regards
Henk

 

[Omnimill]

I'm not familiar with your machine but that doesn't sound right to me, I would have expected the drawbar to simply pull out once it's been unscrewed as you suggest. There must be a few folks on here with your type of mill so hopefully you will get a definitive answer soon!

Vic.

 

[Bluechip]

Henk

Not quite sure what your problem is, but ...

Looks a bit like my WM16 Warco.

It has a 'captive' draw bar. Try removing the top nut completely, then the captive drawbar will pull out.

I assume from your post you have no tooling in the Taper socket ??

Otherwise, if there is, you have to slacken the top nut by 1 1/2 to 2 turns or so, then (mine is 8mm AF) unscrew the square draw bar end. This ejects any taper tooling.

Sorry if it seems pedantic, you need the 25mm (?) AF wrench on the flats at the bottom of the spindle to hold the spindle while you do all this.

Dave BC

 

[cidrontmg]

Hi Henk, I have a BF-16 (Quantum) mill, and I think its drawbar system is +/- identical to a a BF-25. My interest in removing/changing the drawbar is that I have some MT2 tooling that have imperial (3/8" x 16TPI) threads, while the original drawbar is metric (M10). So I made another imperial drawbar for those tools, and change when I need.
Anyway, the drawbar should definitely be quite free to rotate when there´s no tooling attached. Two fingers, and mine spins just like that. How about a squirt of WD-40 in yours? Any freer?
Bluechip beat me to it, but just once more, to remove the drawbar, you need first to remove any tooling from the MT2(3) socket. Then, you hold the bottom end of the spindle with a wrench (where you would hold it when changing tools), in my case the flats are for an M28. At the drawbar end, where the square drawbar nut is, there´s also two machined flats, in my case for an M17 spanner. Just wrench it open, and there´s a longish sleeve that comes up from the drawbar end, which holds the drawbar in place. Now you can pull the drawbar out. And change it, if need be.
Yours just might be bent, or there´s a burr, or there´s grease gone solid, whatever, you´ll find out! But it should be very free to turn.
Hope this helps, can´t be 100% certain that yours is exactly the same, just making an educated guess ;D

 

[deverett]

Henk

My Wabeco mill uses a differential thread on the drawbar ends. The bottom has the usual 3/8" BSW or M10 thread and the top has a fine pitch thread. By using the hex key to unscrew the drawbar, the tool is ejected. To withdraw the drawbar from the spindle, I need to keep unscrewing the drawbar until it becomes disengaged. Not the most user friendly system to be sure. A captive nut on the top of the spindle is much easier to use, but...

Dave
The Emerald Isle

 

[bentprop]

Henk,I see you're dutch,so I'm thinking you may have your terminology crossed.
The "drawbar" is a long steel bolt,with about 20-25mm of thread at the bottom,probably M12 thread.This goes in from the top of the machine,under the black plastic cover,which just lifts off.
This screws into whatever tool you put in the "spindle",perhaps a collet chuck,most likely a Morse taper fitting.
With a variable speed machine,I imagine the spindle is permanently engaged,so that would mean it is hard to turn when the machine is switched off.Is that what you mean?

 

[Henk]

Thanks for the answers!

Bluechip : You are not at all pedantic in your last remark, I had not noticed any flat on the bottom end of the spindle...
cidrontmg : Looks like your suggestion is the same

I am currently at work, so I cannot check, but your suggestions ring true, and I will check immediately when I do come home.

Steamdave: I did try to continue unscrewing the drawbar, but to no avail, so it seems we have a different drawbar design

bentprop : The spindle does rotate, but you do feel the motor / gear "bumps" (for lack of better wording). By the way I actually had to look up the dutch word for drawbar (in the trilingual not very usefull manual), as I learned what a drawbar was mainly on this and likewise English language forums.

Thanks again,
Henk

 

[Bluechip]

Henk

If it helps, this is the drawbar assembly removed from my Warco WM16 mill.

Yours may or may not be the same. Maybe a look at the Parts Listing.?

My mill does the same when I turn the spindle. I think the high/low speed gears are er .. not too precise ???

I call it 'cogging' ;D

Somewhat like the effect of turning a stepper motor.

On high gear it's very slight, but on low gear it's quite noticeable.

Had the mill about 18 months, does not seem to be fatal.


Dave BC

 

[Henk]

Dave,

Looks like the same design type drawbar, at least according to the exploded view in the manual. However, in that view the top nut is absent.

But in your picture the top nut looks like mine so my hopes are high (I am still at the office - really wanting to have a look at home...).

Regards
Henk

 

[Henk]

I had a very quick look before dinner directly after I came home.

Disappointing : no flat part on the bottom of the spindle. The positive thing was that I was rather convinced (and hoped) that I would have spotted a flat there last night as well - no consolation however. Bummer. However, given your combined input I was encouraged that indeed the top nut was just that: a nut.

I just needed a way to stop the spindle turning. Wait! I had also purchased a collet chuck which provided a good flat after it was inserted and engaged. Now why didn't I think of that before?

Now I have the drawbar sitting on my bench and indeed it is the same type as Dave's.

It looks like the problem is caused by a combination of
1) crooked top nut
2) (only slightly) bent drawbar
3) Some "stuff" / rust whatever inside the spindle.

I only had a few minutes time to have a look this evening as I had to see the soccer semifinals. Coming evenignes, I will have a more detailed look, and keep you posted on any findings.

Again thanks for the help.
Regards
Henk

 

[lordedmond]

Why mess with it you just purchased it ,paid for it with perfect money , not faulty money

send it back or get them to sort it out for you , if its in the state you say then you will need new parts , try to convince them you have not broke it now you have it in bits


BTW I to have a new mill delivered the two extras draw bar where for a different model X3 instead of SX3 ( then are 25 mm shorter with a different top ), I just contacted the supplier who supplied the correct ones without any problem

Sorry for the statement but to many suppliers of these things seem to get away with faulty machines, due to the fact that we ( in general ) like to sort out the problems ourselves . you would not do the same with a new car or household goods so why do it with tools, you paid good money you should have goods in return that are fit for purpose

Stuart

 

[Henk]

Stuart,

>Why mess with it you just purchased it ,paid for it with perfect money , not faulty money

I fully agree - however I did not look forward to reloading the mill into my car. For a mill it is not that heavy, but ~130 kg is a lot to me. Alternative would be to remove the mill head and take that with me - which is what I would have tried had I not been able to remove the drawbar + topnut.

Vendor has already suggested sending drawbar to them for replacement (though no details who should be paying for shipment yet). So so far I have no issue with the vendor. Slightly disappointed yes, as he stated that all mills of this type have a wobbly top nut (BTW mine showed ~0.8 mm TIR wobble) - and it should not be a problem.

So next action is to return both the top nut and drawbar and try the replacements. I am undecided yet as to driving back (1,5 hours single trip) or send it back by mail.

Henk

 

[lordedmond]

There should be no "try" in the equation if the parts are faulty then they ( the supplier ) should replace at their cost postage both ways

as to the statement that all the nuts are wobbly I would take that with a pinch of salt.


I think I take a hard line with the suppliers because I need personal wheels to get about so wasting my time with faulty NEW machines gets my back up



just come in from making pipe fitting for 1/16 inch ( 1.6 mm ) pipe, cones and unions got to make about 50 for the loco ( 1/16 pipe is for the oil lines )

Stuart

 

[wla421]

Hi,

No help with your drawbar issue but I do have a question.

Does anyone know where I might be able to obtain a drawbar in 3/8" threads, that will fit my mill?

My Optimum BF20 L, is with M2 taper, the drawbar in M10 threads.

I have had a LOT of milling cutters given to my in Inch sizes, and I know where to obtain Inch collets, but they are in inch....I need a drawbar in inch.

Thanks,

George

 

[tel]

The simple way, George, is to get a piece of 3/8" all thread, cut it off to the appropriate length, loctite two nuts on one end and and you have it.