Bridgeport Series 1 MDI Conversion

[swarf-boy]

Just been checking out your acorn control.
Interesting unit. Quite a lot in the Kit.

Options seem to get strangely pricey though
( $45 for a dual circuit E-stop, being a stand out).

See those 4 series drives look to have built in S curve feature.
Didn't know that was a feature in drives. ( every day is a school day, as they say).

[Chaz]

Just been checking out your acorn control.
Interesting unit. Quite a lot in the Kit.

Options seem to get strangely pricey though
( $45 for a dual circuit E-stop, being a stand out).

See those 4 series drives look to have built in S curve feature.
Didn't know that was a feature in drives. ( every day is a school day, as they say).

Yep, mine was ordered on Wednesday, import tax is a bit harsh, might be delivered today or Monday latest.

I have some potential Panasonic servo motors sorted, will check over the weekend and see if they will work then i need to sort out mounting / pulleys.

[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?

[swarf-boy]

Lots of consideration to take into account.

My machine worked well with the original motors, (it was fully functional on 3 phase when purchased). As previously mentioned, I was also very conscious of electrical max demand of finished machine, as well as keeping running costs reasonable.

The 1.5KW version might have been a choice otherwise, as you could just pull the rotors out of the motors and machine the shaft ends down.
Or fit different pulleys, as mine are tapered collet type. Having said that, I could probably bore out originals and broach a key way in to fit those 19mm shafts. Extra length makes no difference on Z or Y on my Interact. Your MDI has a longer X axis cover for the manual handles, so it may make no issues there either.

Only things that may catch you out is the rotor inertia and the possible effect of having so much Torque. ( although you might find a 4NM version in 110ST.

I partly figured that if my 90st 4NM versions ended up being too small in the end, I could always use them on the next project ( cnc lathe).

Guess its all a gamble really. The only good thing ( in my view) is that as they are 220V AC, there is no need for huge power supplies and torriods. Time will tell

Mark.

[Chaz]

Lots of consideration to take into account.

My machine worked well with the original motors, (it was fully functional on 3 phase when purchased). As previously mentioned, I was also very conscious of electrical max demand of finished machine, as well as keeping running costs reasonable.

The 1.5KW version might have been a choice otherwise, as you could just pull the rotors out of the motors and machine the shaft ends down.
Or fit different pulleys, as mine are tapered collet type. Having said that, I could probably bore out originals and broach a key way in to fit those 19mm shafts. Extra length makes no difference on Z or Y on my Interact. Your MDI has a longer X axis cover for the manual handles, so it may make no issues there either.

Only things that may catch you out is the rotor inertia and the possible effect of having so much Torque. ( although you might find a 4NM version in 110ST.

I partly figured that if my 90st 4NM versions ended up being too small in the end, I could always use them on the next project ( cnc lathe).

Guess its all a gamble really. The only good thing ( in my view) is that as they are 220V AC, there is no need for huge power supplies and torriods. Time will tell

Mark.

Thanks. Good points. Torque can be limited. I'd rather have too little than too much - that said, is rotor inertia a real concern?

Thheir 0.8 KW is 2K RPM, the 1.2 has the same rotor inertia. The next one down is 0.6 KW, so too small in this frame size.

[Chaz]

In the end I was able to get some Panasonic stock from the supplier of my previous kit used on my other mill (Thor)

I will have 2 x 0.75KW and 1 x 1.0KW available. Ill likely install the 1.0KW setup on Thor and then have the same three for the Bridgeport.

[Chaz]

Managed to get two of these 800 x 600 x 300 enclosures for fairly cheap. Perfect for this (I was thinking to use the original box), but this will work too.

Testing a layout. Any thoughts / concerns with what I am proposing? The VFD will be placed externally.

Thanks