How interchangeable are B-port risers.

So we have B-port mills and many brands like Jet, Enco, no-name and known names.
Many appear to be copies or clones. Some appear very close but have more metal in some places. Some I think may have less metal.

But will a riser from one fit another without some "massaging" ?
A machine without a riser block is just about useless to me and I have always spent the long dollar and bought the matching one with the machine.
Perhaps money to be saved on e-yuck nowadays.

Are the clones that look alike the same dimensions or is there a metric/english difference?
Asking for been there done that.
I have wondered about if I was leaving money on the table or waiting for long deliveries with a machine on the floor that I can't efficiently use sometimes.
I've never measured them across the brands and models that I have owned which now that I think about it makes me......
Bob

CarbideBob said:

But will a riser from one fit another without some "massaging" ?

Click to expand...

I wouldn't bet the farm on it nor would I say positively no.
Jet appears to be different because somebody made one and posted the dimensions. http://www.practicalmachinist.com/vb/general/scratch-built-riser-jet-jvm-836-1-mill-312837/

Somebody had posted a drawing of a stock BP riser, but I can't find. Here's what is being sold on Ebone Milling Machine Riser Block 6" for Bridgeport-Type Knee Mills 6inch | eBay

JR

I have an old Beaver vbrp, made in england with a nmtb 30 spindle. I have been wondering if I could adapt a bp riser to it as well

I have a riser for a Kondia around here somewhere that does not fit a Bridgeport.

Personal experience here , a BP riser will NOT fit a Sharp ! And a Webb riser needs to be modified to fit a BP as the male pilot is to big .

Blazemaster said:

I have an old Beaver vbrp, made in england with a nmtb 30 spindle. I have been wondering if I could adapt a bp riser to it as well

Click to expand...

The difference between the Beaver mills and the Bridgeport ones is that the Beaver uses a circular T slot with four T bolts to secure the head, whereas the Bridgeport uses a single spider and a cam to secure the head.

I'm in the process of making an 8" riser for my Mk1 VBRP. I got a couple of 10" id by 14" OD 15mm thick blanks plasma cut by a local general engineering company and I will be welding 100mmx100mmx8mm angle pieces between the two rings to make the riser. The corrugated/zig-zag construction produced by making the vertical spacers from angle will allow access for the clamping screws. After milling the two ends parallel, I'll drill one end for clearance holes for the clamping screws to the column casting and tap holes in the other end to take the original two part T slot rings. All of these operations can be done on a rotary table on the mill.

If you've lifted the ram off the top of the column, you'll probably know what I'm getting at...

Catalogs

about page 4 shows a bunch of different machines with riser dimensions

I guess I need to practice sizing my uploads....click the link in my last post that just says "Catalogs" the link is good to hqtinc.com tool catalog.

I posted some Bridgeport round ram riser dimensions several years ago: BP Round Ram Riser dimensions