A friend who drives a 1955 Chevy pickup had a lot of trouble getting a new lever for his steering gear. The steering gear that is installed in his Chevy does not appear to be the original anymore. Unknowingly, he had ordered an original lever from the USA, but it didn't fit.
The problem is that the lever is mounted with a conical spline and is positioned over four index faces.
Luckily the serrations in the original lever were smaller so it was possible to machine larger serrations into that lever.
I solved the problem on a MIKRON WF3DCM with HDH 150Q control by making a special tool with four cutting edges, so that I could machine four teeth in one position of the dividing head. The advantage of the MIKRON is that the tool holder can be positioned with a holder, secured against twisting.
The first tool was made of hardened 115CrV4 steel. But this wore out too quickly, so I made a tool with four cutting inserts.
First, I made a few test pieces out of aluminum to try out the best fit directly on the vehicle. Otherwise you would have had to remove the steering gear.
The appropriate fit was then produced using two programs. One for the conical bore and a second parameter program for broaching the conical gearing.
The knife moves in a diagonal Z and Y downward movement according to the cone. The delivery takes place in Y.
If one tooth is finished, the coordinate system swivels by 90°. The process is repeated 4 times. So, for 32 teeth I only had to swivel 8 times.
I have a 144MB video of the process but have no idea if I can embed videos here.....
Manufacturing in this way is certainly not very economical. But what don't you do for a friend or a '55 Chevy...
Parameters:
3 FN 0 : Q10= +29,200 upper diameter
4 FN 0 : Q20= +27,800 lower diameter
5 FN 0 : Q30= +24,000 depht
6 FN 0 : Q40= +0,050 delivery
7 FN 0 : Q60= +9,775 tool radius
HAIDENHAIN 150Q code for my conical slotting
0 BEGIN PGM 8095 MM
1 TOOL DEF 80 L+0,000 R+9,775
2 TOOL CALL 80 Z S 31,500
3 FN 0 : Q10= +29,200
4 FN 0 : Q20= +27,800
5 FN 0 : Q30= +24,000
6 FN 0 : Q40= +0,050
7 FN 0 : Q60= +9,775
8 FN 2 : Q15= +Q10 - +Q20
9 FN 4 : Q50= +Q15 DIV +2,000
10 FN 4 : Q11= +Q10 DIV +2,000
11 FN 2 : Q12= +Q11 - +Q60
12 FN 1 : Q13= +Q50 + +Q40
13 L Z+10,000 R0 F1000 M
14 L X+0,000 Y+0,000 R0 F2000 M
15 L Z+2,000 R0 F1000 M
16 L Y+Q12 R0 F1000 M
17 L Z+0,000 R0 F100 M
18 LBL 1
19 LBL 2
20 L IY-Q50 IZ-Q30 R0 F1000 M
21 L Z+2,000 R0 F1000 M
22 L IY+Q13 R0 F1000 M
23 L Z+0,000 R0 F100 M
24 CALL LBL 2 REP 29 /29
25 L Z+2,000 R0 F1000 M
26 L X+0,000 Y+0,000 R0 F2000 M
27 CYCL DEF 10.0 DREHUNG (rotation cycle)
28 CYCL DEF 10.1 IROT+90,000
29 L Y+Q12 R0 F1000 M
30 L Z+0,000 R0 F100 M
31 LBL 0
32 CALL LBL 1 REP 3 /3
33 L Z+10,000 R0 F1000 M
34 L X+0,000 Y+0,000 R0 F1000 M30
35 END PGM 8095 MM
Cheers