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JoeLee
03-04-2011, 08:00 PM
I just set up the horizontal milling arbor on my Bridgeport as I have to do some slotting. It's easy to adjust the right angle head as it has ground surfaces on either side so you can indicate it in. But what I was wondering is how about indicating the arbor from front to back to make sure it's paralell with the table. Is it nessicary??? or does the back collet bearaing line it up good enough??? Even after mounting the arbor you can still nudge the quill up and down a few thou. but I feel the arbor should be indicated paralell with the table.

JL....................

chipmaker4130
03-04-2011, 08:31 PM
Mmmm... Can't remember for sure, but I think my Burke unit, which is very much like the BP stuff will be right on with the quill retracted until the right angle unit contacts the quill housing. Do you have machined surfaces in those two places?

JoeLee
03-04-2011, 08:46 PM
Not with mine, the top of the right angle attachment is about 1/4" from the bottom of the quill housing. The rear bearing support sets the height of the arbor since it's a fixed height but there is room to play at the quill, but you cant rely on the rear bearing holding the arbor paralell. Your set up sounds nice, less indicating and guess work. I suppose once I get mine zeroed in I could make a gage block for future set ups. The RA attachment does have a ground surface on each side but that isn't for height.

JL.............................

Forrest Addy
03-04-2011, 09:00 PM
Yup. Right angle head, arbor, and end support right?

Dial in the cheek of the head (the machined place). Dial in the naked arbor if precision is needed. The end support bearing slides laterally to bring in the far end of the arbor. Move the quill up or down a trifle to make the arbor parallel to the table.

Setting the arbor accurately to the table and saddle axis helps prevent saw jamming and breakage, particularly on deep cuts.

Is the collet indexing set-screw still in your right angle head? If so you may want to remove it. It's quite common for the R8 to slip in the spindle breaking off the dog point of the screw and rolling it around between the shank and the spindle. Yours can jam things up quite nicely making it very difficult to extract the arbor. Remove the setscrew. It has little torque capacity and a great potential for damaging the inside of your spindle.

JoeLee
03-04-2011, 10:09 PM
Yup. Right angle head, arbor, and end support right?

Dial in the cheek of the head (the machined place). Dial in the naked arbor if precision is needed. The end support bearing slides laterally to bring in the far end of the arbor. Move the quill up or down a trifle to make the arbor parallel to the table.

Setting the arbor accurately to the table and saddle axis helps prevent saw jamming and breakage, particularly on deep cuts.

Is the collet indexing set-screw still in your right angle head? If so you may want to remove it. It's quite common for the R8 to slip in the spindle breaking off the dog point of the screw and rolling it around between the shank and the spindle. Yours can jam things up quite nicely making it very difficult to extract the arbor. Remove the setscrew. It has little torque capacity and a great potential for damaging the inside of your spindle.

Yes the set screw is still in the RA angle spindle. I take it that the small hole in the side of the RA attachment housing is for removing that set screw.

JL..................

John Stevenson
03-05-2011, 05:36 AM
Needs to be dialed in on the Bridgy, Correct way in keeping with the machine is to mount to dial gauge on a length of licorice twist.

Not sure if it makes any difference being RH or LH twist ?

.RC.
03-05-2011, 06:09 AM
To me it seems there could be complications considering the turret spins around as well...

Is your turret dead square with the table? The only alignment indicators I can think of to use to align it is the dovetails..

Since I have a horizontal support due in the mail any time now (had the right angle head for years, very handy item) I am interested in this thread...

Mine is an ISO30 spindle so no worries about spinning the arbor...

JoeLee
03-05-2011, 09:48 AM
To me it seems there could be complications considering the turret spins around as well...

Is your turret dead square with the table? The only alignment indicators I can think of to use to align it is the dovetails..

Since I have a horizontal support due in the mail any time now (had the right angle head for years, very handy item) I am interested in this thread...

Mine is an ISO30 spindle so no worries about spinning the arbor...

That brings another thought to mind.......... I never thought of checking the turret, I've never moved it as it's set on "0" but that is just the graduation mark on the ring. I indicated the RA attachment perp. to the table by running the table in and out, it zeroed out fine. Then I put the long arbor in the attachment and tightened up the nut, then I just pulled the rear support in toward the end of the arbor untill the arbor end slid into the collet bearing and then locked the rear support down. Given the fact that the arbor is true there should be no binding, any adjustment of the rear support bearing or up/down adjustment of the quill from there would just be springing the arbor for a desired reading.

JL................

.RC.
03-05-2011, 03:15 PM
Actually on second thought the turret would not be that critical....As the support has some sideways adjustment, and although it would mean some minor misalignment of the arbor as it goes through the support bushing, it would be very minimal..