# Bridgeport Right Angle Attachment Mounting



## Hit-N-Miss Tom (Dec 29, 2017)

I have a MSC, Bridgeport like machine, and am attaching for the first time a Right Angle Attachment for some horizontal milling. It appears the quill is fully into it and bottoming out on its inside base, with its R8 type center shaft into the quill. When I engage the bolt (longer one that goes through the quill to hold the collet and came with the unit) I believe I am only getting a few threads to connect and I don't feel enough threads are engaging. It certainly is nothing like normal R8 collet use for end mills.

Does anyone know about how many threads (or turns) should be engaging?


----------



## 4GSR (Dec 29, 2017)

You need about an 1/2" of thread engagement as a minimum.  If you are getting less than this toss the bolt or sock head cap screw and get you a longer one to replace it. Don't surprise that you may have to modify a screw to get the length needed.


----------



## BGHansen (Dec 29, 2017)

Hi Tom,

Here's a thread with my set up.

http://hobby-machinist.com/threads/right-angle-head-set-up.64232/#post-533099

My Eisen (Gem Power) right angle head came with a draw bar extension.  My draw bar engaged at least 1/2" and probably closer to 3/4" or more.  I held the spindle of the RAH with a spanner wrench while tightening the draw bar.

You may want to pull your draw bar for starters and check the threading into the RAH on the bench.  Mine didn't thread in very well but I tried installing it to my Bridgeport anyhow.  Well, snapped the draw bar off in the arbor of the RAH.  My draw bar was shop made from at least 4140 if not 1080.  I ended up pulling the RAH apart and drilled out the draw bar end with a carbide end mill, then an EZ-out.  Probably more than you wanted to know, but I'd recommend checking the thread on the bench for starters.  I ended up making another draw bar with the threads a little undersized so it would thread better into my head.  I couldn't get a 7/16"-20 tap to go very deep into the head.

The attached thread doesn't show a great picture of the draw bar extension; it's a 3/4" socket on one end, 3/4" hex on the other.  You should be able to use a 3/4" socket with an extension and run it down with a ratchet.

Bruce


----------



## Frank Ford (Dec 29, 2017)

I use a power drawbar on my mill, and the last thing I wanted to do was take all that gear off the top just to use a right angle attachment, so I made some a simple modification to the attachment.  Without any loss of function, I can now mount the right angle setup quickly and easily:




Here's the full story:  http://www.frets.com/HomeShopTech/Projects/HorizMillAttach/horizmillattach.html


----------



## Hit-N-Miss Tom (Dec 31, 2017)

4gsr said:


> You need about an 1/2" of thread engagement as a minimum.  If you are getting less than this toss the bolt or sock head cap screw and get you a longer one to replace it. Don't surprise that you may have to modify a screw to get the length needed.





Frank Ford said:


> I use a power drawbar on my mill, and the last thing I wanted to do was take all that gear off the top just to use a right angle attachment, so I made some a simple modification to the attachment.  Without any loss of function, I can now mount the right angle setup quickly and easily:
> 
> View attachment 252372
> 
> ...


I don't think I will be using horizontal too much, but what you did sounds very interesting to check out. Thanks!


----------



## Hit-N-Miss Tom (Dec 31, 2017)

BGHansen said:


> Hi Tom,
> 
> Here's a thread with my set up.
> 
> ...


I spent some time messing around with it Saturday and believe I was having the same problem with threads. I didn't break my arbor (yet) and after reading your problem I am sure I will be chasing some threads, and rechecking off the machine. Thanks!


----------



## Jonathans (Jan 3, 2018)

Thanks for sharing a great solution for those of us that use power drawbars Frank.


Frank Ford said:


> I use a power drawbar on my mill, and the last thing I wanted to do was take all that gear off the top just to use a right angle attachment, so I made some a simple modification to the attachment.  Without any loss of function, I can now mount the right angle setup quickly and easily:
> 
> View attachment 252372
> 
> ...



Its now on my to do list


----------

