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BT40 tooling in a CT40 toolchanger and spindle?

rpseguin

Stainless
Joined
Jun 28, 2006
Location
Napa, CA
I’m looking at a Small VMC, but it’s a CT40 spindle and toolchanger and I have BT40 tooling.
Can you run BT40 tooling in a CT40 spindle and toolchanger?
I think I remember reading something that you could possibly change some parameters (height presumably?) and possibly some other things to get it to work.
What hardware changes need to happen?
What parameter changes (Fanuc control)?
 
I too know what it's like to have each type in one shop. Kind of like metric/SAE wrenches and sockets. Need to buy a set of each.

Like Rooster said, manual changing will work if you have exactly the right pull stud. Not always the easiest thing to find.

If you're really serious, many MTB's offer their machines in BT or CAT. My experience with this is you only need to change out the claws at the end of the changer arm to fit your tool style. And again, get the right pull stud. If you do this, be sure to check out your Z axis height before punching in that first M6. There also may be a little signage on the machine about tool shape and pull stud that won't be correct anymore, so should be changed as well.

Dave
 
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I too know what it's like to have each type in one shop. Kind of like metric/SAE wrenches and sockets. Need to buy a set of each.

Like Rooster said, manual changing will work if you have exactly the right pull stud. Not always the easiest thing to find.

Thanks!
I thought pull studs were semi standardized other than the angles.
Is it just a matter of getting the right angle pull studs, or is there some other difference that is important? Length?

If you're really serious, many MTB's offer their machines in BT or CAT. My experience with this is you only need to change out the claws at the end of the changer arm to fit your tool style. And again, get the right pull stud. If you do this, be sure to check out your Z axis height before punching in that first M6. There also may be a little signage on the machine about tool shape and pull stud that won't be correct anymore, so should be changed as well.

Dave

The machine I’m looking at has an carousel/umbrella type toolchanger. (I wishe it were the sidemount/swingarm type).

So, I’d need to change every holder position in the carousel then, right?
And find/change Z axis height parameter(s) for tool change.
Anybody know what parameter the tool change Z axis height is on Fanuc?
 
You could use the tools but only in a manual capacity. The flanges are way different and will jam up in an auto toolxhange.

Thanks!
The toolchanger is a carousel/umbrella type.
I’m sure it would probably be expensive to change out every position on the carousel.
 
Thanks!
I thought pull studs were semi standardized other than the angles.
Is it just a matter of getting the right angle pull studs, or is there some other difference that is important? Length?



The machine I’m looking at has an carousel/umbrella type toolchanger. (I wishe it were the sidemount/swingarm type).

So, I’d need to change every holder position in the carousel then, right?
And find/change Z axis height parameter(s) for tool change.
Anybody know what parameter the tool change Z axis height is on Fanuc?

doesnt make any difference what kinda control it is. as some machines have there own defined parm # for tool height not a funuc factory standard
you might start by saying what machine it is and maybe a year.
as some machines you have to replace the carousel, some you can just turn over others you just change clips

bt are metric threaded studs cat are sae threaded studs. also why they all have the same angle (BT and cat) they have different gage heights/lengths

for example a supermax mill requires a different carousel , a fadal just needs to have clips changed etc etc
 
Thanks!
I thought pull studs were semi standardized other than the angles.
Is it just a matter of getting the right angle pull studs, or is there some other difference that is important? Length?
Hello rpseguin,
The length of the Tool Holder from Taper Gauge Line to the face where the Pull Stud flange contacts is shorter for a BT40 Tool Holder. Accordingly, for a given make of machine the difference in the Pull Stud for BT and CAT specification is the length from the face of the Pull Stud flange that contacts the end of the Tool Holder to a reference on the Pull Stud Knob. Therefore, the position of the Pull Stud Draw Bar, relative to the face of the Spindle Nose is the same for BT and CAT specification machines. Basically, only the length of the Pull Stud, their Thread and Tool Change Gripper Slippers are different between the two specifications of machines

The machine I’m looking at has an carousel/umbrella type toolchanger. (I wishe it were the sidemount/swingarm type).

So, I’d need to change every holder position in the carousel then, right?
And find/change Z axis height parameter(s) for tool change.
Anybody know what parameter the tool change Z axis height is on Fanuc?

Being a Side Mount, or Umbrella Style Tool Change will make no difference as to whether the height for the Tool Change has to be modified. In the overwhelming number of cases, it involves changing the position of the Spindle rather than a change in the height position of the Tool Change mechanism.

The parameter to change will depend on how the position for Tool Change is achieved by either the PMC, or Tool Change Macro. Some machines with an Umbrella Style Tool Change use a hydraulic, or pneumatic arrangement to move the mechanism up and down, relative to a stationary Spindle. Mostly, the Tool Change mechanism has no movement parallel with the Z axis, but the Z axis moving Up and Down to eject and capture the tool. Whatever the method used, the Spindle Nose and hence, the Tool Change Ring of any tool that may be in the Spindle, must be at a position that matches the position of the Tool Change gripper.

The Position of the Spindle Nose can be adjusted by altering the Z Reference Return Position (G28) and or a Second Reference Return Position (G30). As second, third, etc. Reference Return Positions are set as Relative Distances from the G28 Position, changing the G28 (Reference Return Position) will also change the G30 Position.

Regards,

Bill
 
Buy new holders. It is the cheapest and best solution. When installing new machines we can often change from CT to BT or vice versa on the machine. The tool arm, spindle nose and often the tool storage system are all changed out and then software is updated.
 
its gonna depend on the machine, I just got a new to me machine that used CT holders and changed it over.

according to the people that know I would have to put all new grippers in it, when I got it here I tried the BT holder and it fitted really well, tweeked the tool change height and away it went.
 
I guess it depends on how the machine and toolchanger are built. Some carousels don't use the V to engage the tools, just clamp on the top and bottom of the flange, for example. Most machines that I've seen would require a LOT of parts changed to make the conversion. One big difference is that CAT tools have a maximum diameter for a specified length on the side of the flange opposite the taper, and BT tools don't. So BT machines are more lenient on the tools that they can use.
 
There is no way a CT tool gripper will fit a BT flange "well". The groove in a BT is nearly twice as wide as the groove on a CT.

I don't have any CT tooling here to compare, all I know is that the machine that was running CT tooling at its last home is now running BT. the tools are just as secure as they are in the native BT machine next to it.

merely pointing out that in some cases its easy to swap over, I'm sure in some cases its a nightmare!
 
The bridgeport I had was CAT 40. The carousel was loaded with CAT 40 when I bought it. I ran CAT 40 the whole time I owned it.

Wasn't till I was digging through the manuals trying to fix an issue that I noticed..... BT 40???!!!!

Sure enough, the machine was built BT 40. Called the guy I bought it from. Oh... yea, somewhere down the line someone made it CAT 40. Only difference was the height position for the tool change?
 








 
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