What's new
What's new

Weird Wohlhaupter UP4 MT4 + TOS FN22 problem

JFW

Aluminum
Joined
Dec 17, 2006
Location
Oslo
Hi guys,

Just picked up a Wohlhaupter UP4 boring head with a MT4 shank yesterday, and was so happy to get home to fit it up to my TOS FN22 (Deckel FP2 clone). To my surprise the taper on the Wohlhaupter is not long enough, so the shank won't fit! Is this a unique situation, or do others have similar experiences?

All the best,

Truls
 
Last edited:
What do you mean the shank won't fit? Is it to big around to fit the spindle or does it go too far in that the draw bar bottoms out? Does it look like this one pictured? I don't understand and with lack of information I never will; please elaborate.
Dan
 

Attachments

  • DSC00002.JPG
    DSC00002.JPG
    61.2 KB · Views: 592
Hi Danny,

Sorry for the lack of info in the original post. Essentially the taper is correct, but the shank is too short for the spindle-design. In other words: When I try to fit the shank into the spindle it bottoms out against the boring head body before engaging in the taper. Does that make more sense? I'll shoot some pictures tomorrow (late evening over here in Norway now).

Cheers,

Truls
 
Hi again, guys,

From what I can understand/observe, it's only missing a few millimeters to engange in the taper. What I think is the problem here is that the TOS does have a "drive-flange" below the spindle that eats up room. With a standard MK4 shank on a drill chuck, that's not a problem since the diameter of the shank is so that it fit's further up into the spindle, but with the Wohlhaupter the body of the tool itself hits the "drive-flange" before it engages in the taper. The tool is hardened, so getting the much needed millimeters would require it to be ground. Not worth it, I guess. So, off to the classifieds again. Quick video here: https://www.youtube.com/watch?v=nmlq2T9X93k

Cheers,

Truls
 
Hi again, guys,

From what I can understand/observe, it's only missing a few millimeters to engange in the taper. What I think is the problem here is that the TOS does have a "drive-flange" below the spindle that eats up room. With a standard MK4 shank on a drill chuck, that's not a problem since the diameter of the shank is so that it fit's further up into the spindle, but with the Wohlhaupter the body of the tool itself hits the "drive-flange" before it engages in the taper. The tool is hardened, so getting the much needed millimeters would require it to be ground. Not worth it, I guess. So, off to the classifieds again. Quick video here: https://www.youtube.com/watch?v=nmlq2T9X93k

Cheers,

Truls

I watched that video and have noted the shank on the boring head. I have never seen one with Morse taper that had a slot through it, Deckel uses a 20 X 2 MM buttress thread for a draw bar. Possibly for a special machine spindle, might find out it's worth more to sell it than you paid for it?
Dan
 
The slot is usual on Wohlhaupter MT shanks although I don't now its purpose. Probably some kind of retention device for specific drawbar less spindles.

As for the shank diameter, the "root" diameter of an MT4 taper should be somewhere around 31,6mm.

Check that dimension on your boring head attachment and you'll quickly know if you have a special MT3,75, or if it's your sleeves that makes the mess.
 
Hello Truls,

You have a different spindle in your TOS with that rectangular slot,this is some Czech invention what I have seen before.
They made in the past MT4 holders with corresponding flats which fits in the slot.

This is screenshot from the Narex VHU catalog:

5-10-2015 11-06-05.jpg

The taper is indeed longer you need, and your spindle is too long.

You may change your Wohlhaupter but only if it is hollow from top and you find an allen screw in the bottom. carefull it is Left threaded!

Succes!

Best regards,
Michael
 
FYI:
Retention slots through Morse tooling are used with older "Morse" spindle horizontal boring machines. Tool is inserted in the spindle and a retaining
"wedge" driven through the slot in both the spindle and tool for rentention.....Quite common on older boring machines such as "Lucas, G&L etc......
These machines did not have draw bars and were built to use existing Morse tooling (drills etc.) and used the slot and wedge system for tool retention plus
a wedge/ drift to remove same......Later versions were built to have NMTB spindle tapers that took better advantage of milling machine tool holding.

You are quite sure you have a "Morse" tool shank, yes????? Should say so on the boring head.

Cheers Ross
 
FYI:
Retention slots through Morse tooling are used with older "Morse" spindle horizontal boring machines. Tool is inserted in the spindle and a retaining
"wedge" driven through the slot in both the spindle and tool for rentention.....Quite common on older boring machines such as "Lucas, G&L etc......
These machines did not have draw bars and were built to use existing Morse tooling (drills etc.) and used the slot and wedge system for tool retention plus
a wedge/ drift to remove same......Later versions were built to have NMTB spindle tapers that took better advantage of milling machine tool holding.

You are quite sure you have a "Morse" tool shank, yes????? Should say so on the boring head.

Cheers Ross
Interesting read; I had wondered how those big machines worked using morse tapers and what kept them from falling out.
So much for the added value to the boring/facing head idea.
Dan
 
This thread is probably long dead.
But this information may come in handy for someone that reads it.
Some Tos FN22 machines were also manufactured with metric spindle tapers!
The Me32 taper at first glance looks just like an MT4.
It has 1:20 taper and the large diameter of the taper is 32mm. Me32 tooling also often comes with those drive flats.
 
This thread is probably long dead.
But this information may come in handy for someone that reads it.
Some Tos FN22 machines were also manufactured with metric spindle tapers!
The Me32 taper at first glance looks just like an MT4.
It has 1:20 taper and the large diameter of the taper is 32mm. Me32 tooling also often comes with those drive flats.


On the video he shows that a MT4 drill fits So I do not think this is a Me32 taper 1:20
But thanks for the info anyhow

Peter
 








 
Back
Top