Best Way To Mate A Grizzly/bald Eagle Spider To Backplate

Bamban

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I am putting together a Taiwanese 10x24 lathe, the project includes VFD/3P system and building a spider chuck. The lathe was gifted to me motorless and chuckless. BIG thanks to our member, mksj, the motor part is under control.

For the spider chuck I finally found a backplate on eBay, and bought the Grizzly 5 inch Bald Eagle spider chuck. The problem, though both have mounting holes in them but the bolt centers do not match, I have to drill and tap the back plate to match the spider mounting holes. The center holes are different diameters.

The question. What is the best way to set up and mate the 2 pieces together and ensure the they are on the same axis when bolted togetherFederal PC 23 10x24 Backplate.png Bald Eagle Spider.jpg ?
 
To answer we need to know what tools you have to work with. I would mount the back plate to the lathe and use the tail stock with a live center to hold the chuck to the back plate. indicat it in and use a transfer puntch to mark new holes.
 
Thank you.

I have a Bridgeport, super spacer with 3J, rotary table, a Blake, a self centering Bison vise, Kurt 6 inch, and drills and end mills.

The problem the lathe I will use this is not in operation yet, I need to finish this spider so I have a chuck to use when I start checking the lathe out.

I have another lathe but it is a D1-4 spindle.

Could I do this on the mill?
 
Shure you can do it on the mill. A couple of ways with what you have. If you have a dro that does bolt circles would be one way. Or you you have a rotary table.
You can use that center the back plate on the RT in the mill. mesure the bolt circle of the chuck end drill it. Scence you have another lathe you could make a pluge to screw in to the face plate and slide the chuck over it and drill the holes that way.
 
What are you going to use that chuck for. I looked on grizzly's site and thay say chamber reaming small barrels. But it doesn't look like it will hold well enough for any typ of machining.
 
Shure you can do it on the mill. A couple of ways with what you have. If you have a dro that does bolt circles would be one way. Or you you have a rotary table.
You can use that center the back plate on the RT in the mill. mesure the bolt circle of the chuck end drill it. Scence you have another lathe you could make a pluge to screw in to the face plate and slide the chuck over it and drill the holes that way.

Thank you.

This is the first attempt for me to mate these 2 pieces together, I appreciate the options you brought up. I have to see if the DRO has the capability to do bolt circles.
 
When I have to drill a bolt circle eather wth adro or RT I will take a spotting drill and lightley marke each hole and check it before I drill it.
 
I would mount backplate . Then counterbore the 6 inch backplate just enough to capture the 5 inch dia of the other plate. Then drill holes on mill. jimsehr
 
Thank you.

I have a Bridgeport, super spacer with 3J, rotary table, a Blake, a self centering Bison vise, Kurt 6 inch, and drills and end mills.

The problem the lathe I will use this is not in operation yet, I need to finish this spider so I have a chuck to use when I start checking the lathe out.

I have another lathe but it is a D1-4 spindle.

Could I do this on the mill?
NOTE - you can't fit the Bald Eagle BE1125 spider to a D1-4 back plate, as it is drilled for four (4) holes and the D1-4 back plate is three (3) hole arrangement. No mater how you turn it, it will not clock (lign-up) without touching a hole in the back plate for drilling/threading/mounting. The only way is to get an extra thick backplate or use a thick faceplate that will allow you to drill up to a hole on the opposite side with out interfering with the D1-4 locking tabs/pegs. The Bald Eagle item is useless! SEE MY UPDATED INFO ON POST #16 USING THE EXTRA THICK BACKPLATE
 
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