Bridgeport Series 1 Interact. Refit/update . Opinions please.

[battwell]

What control are you going with?

[Chaz]

What control are you going with?

Centroid Acorn.

[Chaz]

Hi,

So Centroid ordered, looking at motor options. DMM do a Nema 42 replacement that has the correct shaft length and diameter which helps (roughly 50mm and 5/8th inch) - how are you dealing with pulleys and mounting options for your new motors?

The DMM stuff is pricy too, so looking at options.

Thanks

[swarf-boy]

Had 2 different thoughts on pulleys. ( but that's all they are right now.)

A) Make a shaft extension piece and stick original gear on the
end. ( quick & simple, but depends on length)

B) Make a new gear with an extended boss.
( seems a more engineered solution, but more expensive
and a lot more time to machine from solid. Also I would
have to make a single tooth form tool. Fortunately I already
have a H/V rotary table with dividing plates)

Sickeningly, this would be a great job for the 4/5 axis machine that I hope to end up with ,but isn't that always the way!


Re mounting, my servo motors have a stupid raised boss on the front face. Going to turns this off in the lathe.

X & Y axis should be OK with a flat face.

Z AXIS mounting plate is part of main head casting and has a circular pocket machined in to accept the old SEM motor. ( no way I am stripping that lot off to mess with. Thinking of just making an exact size disk to drop into pocket to level out the surface. Then bolt motor straight on.
The bolt pattern on new motors is a little larger, so just thought of rotation the bodies 45°, marking and drilling a new PCD to suit.

[Chaz]

Had 2 different thoughts on pulleys. ( but that's all they are right now.)

A) Make a shaft extension piece and stick original gear on the
end. ( quick & simple, but depends on length)

B) Make a new gear with an extended boss.
( seems a more engineered solution, but more expensive
and a lot more time to machine from solid. Also I would
have to make a single tooth form tool. Fortunately I already
have a H/V rotary table with dividing plates)

Sickeningly, this would be a great job for the 4/5 axis machine that I hope to end up with ,but isn't that always the way!


Re mounting, my servo motors have a stupid raised boss on the front face. Going to turns this off in the lathe.

X & Y axis should be OK with a flat face.

Z AXIS mounting plate is part of main head casting and has a circular pocket machined in to accept the old SEM motor. ( no way I am stripping that lot off to mess with. Thinking of just making an exact size disk to drop into pocket to level out the surface. Then bolt motor straight on.
The bolt pattern on new motors is a little larger, so just thought of rotation the bodies 45°, marking and drilling a new PCD to suit.

Thanks. I was thinking the same for Z (mine is off however) so if I Can get my spindle to fit in there, ill enlarge the holder. The problem with your approach might be the shaft length as the motor is moved away from the pulley location (might be OK, pending on what you do with the shafts).

[swarf-boy]

Old DC SEM motor Top 2500rpm & 3.4NM torque
and new AC Servo bellow it = 4.0NM torque.
Also note difference in shaft length.


Z axis mounting bracket part of head casting


compared to motor front plate (note raised centre boss).


AC servo in place, showing boss interfering with fit.


Z axis pulley, above spindle ( looks a pig to change out)


original pulley as fitted to SEM motors.


pulley disassembled.


Spindle motor. although it shows Star / Delta link positions, there is no terminal block inside housing.

[Chaz]

Thats the Z Pulley, not spindle pulley :-)

How are you going to make up for the shorter shaft? Our machines look identical, apart from your slightly more powerful motors.

My motor has wires that allow for different options, but this is with the outer metal shield removed, will take pics this weekend.

[swarf-boy]

That's what I meant.
Its a real pain uploading photos on here, and I do it all on my phone. I had it all done, but clipped the back button and lost it all again (LoL), so did it again in a hurry.

[Chaz]

Pic with the motor's outer cover removed. You can see the wires coming out allow for change in connection.

[Chaz]

I'm trying to decide what motor to go for.

80 Size - 19mm shaft but 35mm long.
90 Size - 16mm shaft, same length.

Both those have near identical specs.

110 Size is almost a direct replacement but the shaft is 19mm and longer which is I think is ideal. This is for a 1.5 KW setup, around $100 per setup more expensive (not much of a concern).

Which would you go for?