Deckel FP2 Quill Stiff

[dsatchell]

Hi ,
My FP2 (1970 version) has an extremely stiff quill. Based on a other posts, I've soaked it in penetrating oil, and removed the spindle unit (quill and spindle). I've check the locking lever, (it is working fine), cleaned out the interior with spray lube (not much grit there). After cleaning out the head, I placed the quill back in and the tightness is apparent as soon as the quill is put back into the head casting (first mm or 2), I needed to use a screw press to push it back in (making sure it was aligned with the key).
So now that it's back in, I have no difference in how stiff it is. I would guess that is takes about (maybe more) 10 to 15 lbs, on a 8" lever to move it (up or down). When I engage the locking ring, it feels almost the same (as if it's not making a differentce, but when the quill was out, I can feel that the locking ring is functioning (tightening and loosening).
I'm thinking that the fit is not correct but before I disassemble it again, I'm wondering if maybe this is what it is supposed to be.?
The head is definitly beat-up relative to the rest of the machine whcih is in very good condition. I suspect that the seller swapped out parts, and was wondering if maybe the quill/spindle was switched and therefore is not a matched fit.
Thoughts and guidance would be appreciated.

 

[AlfaGTA]

Measure the quill OD. Check to see if it’s round and parallel,top to bottom.
Measure the housing ID ,check to see if the bore is round and parallel.
A good bore gage is to advantage here!
Carefully measure at the quill clamp to be sure it is not distorted or small.
You did not mention if this was the vertical or horizontal spindle,and if the other quill moves as it should.
Cheers Ross

 

[dsatchell]

Hi Ross,
It is the vertical spindle that has the issue, the horizontal spindle works well. I'll pull it out again and do the measurements. Post when done.

 

[dsatchell]

Hi, I did a few measurements and noticed an 'item'. The OD of the spindle is 2.753 (+/- 0.0005) inches and the ID of the bore is (see note 1) 2.754 (+/ 0.004). Can you let me know if these measurements are accurate enough for an assessment? Note 1 is that I've discovered yet another tool that was ruined due to my basement flooding, so I had to make the measurement for the ID with calipers. One item I discovered in this removal is that the flat nut on the small (of the two internal gears) had fallen off (I had replaced it but did not notice a piece of metal from a washer that was lodged in the top quill gear rack. I rooted it out and then stoned the deformation on the spindle with a precision ground flat. Generally, this improved the movement of the quill to about 1/2 the installation length, but after that, it was as difficult as before. I'm going to pull it again and then measure with a new (to me) boring gage once I get it, as I don't think the ID measurements are adequate. The other item I noticed, is that there is a roughness in the bearings, I'm guessing that all of the light oil I've been using has washed some junk into the bearings. Are there any particular issues or challenges with pulling and replacing the bearings ( from the drawings I see 2 needle and 2 round (not sure what type yet)?

 

[AlfaGTA]

Replacing the spindle bearings may be problematic.
Deckel spindles do not have replaceable inner or outer races for the spindles. Needles run directly on the ground surface of the spindle (OD) and the ground surface of the quill (ID). To account for manufacturing tolerances the clearance between ID and OD is adjusted by using needle rollers in graded size steps. These are special and generally not available from normal bearing supply sources.
When I say “steps” I am talking size changes in the micron range. Small enough that measurements with normal shop instruments are not reliable.
Generally the size of needles needed is derived by test assembling and gauging the assembled spindle play.
Replacement needles can be acquired from the usual Deckel specialists (FPS, Singer etc)
The caged needle assemblies are marked with a code indicating a size plus or minus the nominal diameter of the needles in microns.
If spindle runs rough, suggest disassembly, clean, lube (special Kluber) and reassemble.
Singer will preform this service but it requires shipping the spindle assembly to Germany and return.
Have posted a thread on spindle rebuild
Do a search.
To do this class of work you will need at the least a good quality 10’s reading test indicator and magnetic base (Noga)
And a clean well lit work space.
Would not continue to rotate the spindle if it is rough as that could add damage to the fine finishes and precision parts.

Calipers are not accurate enough to gauge quill and housing clearances. Nor are they accurate enough to gauge the truth of the parts (round/parallel)
You are looking for issues in the tenths range.

Cheers Ross

 

[dsatchell]

Hi, I found this thread (is the one you referred to?)

Deckel spindle bearings

Iam thinking of getting a Deckel. I was looking at a view of the spindle bearing set up. This is a very simular set up to one that I work on often. The rollers at the nose can be delt with using a lap piloted by the ball bearings at the rear. With care this can be done to extreem acuracy with...

www.practicalmachinist.com

For the mentioned spindle run out test, did they put a bar in the spindle and then push from a specific distance, or just push on the spindle (e.g. with a thumb from inside).

Super information, I'm considering cleaning the bearings. I'd like to take some measurements of the current run out to gage what I'm seeing.
That was my thought as well with the calipers, thanks for the recommendation on the setup.

 

[AlfaGTA]

A lap will increase the ID is the quill if it has any effect at all, so you need a way to compensate for the change. Obvious solution is oversize rolling elements. Shops that do this work on a regular basis have stocks of stepped sized needles allowing test assembly to verify final assembly.
On Deckel spindles I use a tenths indicator, mag base on the quill, indicator against the side of the spindle at the working end. Normal hand pressure pushing opposite.
.0002-.0003 movement without grease (light oil to prevent microscopic point welding)
End float should be set to .0004-.0005”.
These spindles are setup without preload unlike angular contact ball bearing setups.
Cheers Ross

 

[dsatchell]

Finally received the dial bore gage, what I found were three locations in the ID of the vertical head stock that were about 0.3 thou above the normal readings. two around each side of the opening for the quill pinion, and 1 near one side of the key way. because, I did not measure any significant difference in the overall diameter, I used a precision ground round stone to burnish down the high spots. This worked well. Following the burnishing, I think it reduced the load needed to move the quill by about half. I'm going to measure again and touch up as needed. I suspect that the piece of the lock washer I found in the head had been dragged down into the quill or possibly some material came in through the quill pinion.

Thank you again for the insight and help