[4]

BRIDGEPORT M HEAD SPINDLE WEAR PROBLEM

[3]
[10] Like what you see?
Click here to donate to this forum and upgrade your account!

Currahee26

New Member
Registered
Joined
Apr 14, 2017
Messages
22
Greetings. I have an older round ram, M head Bp mill. The spindle is so worn out inside that my Morse taper # 2 (MT2) collets go all the way up inside almost to their widest end before they clamp the bit. So far I can live with this but it consumes almost all of my bit length. My biggest problem is with a NON COLLET tool, such as my MT2 fly cutter and MT2 keyless chuck. they literally rattle around inside the spindle even when inserted all the way! They wont take any milling load and will simply spin off the drawbar. Any suggestions? If I could find a new M head spindle, I'd just buy it and problem solved. So far only used ( and probably also wallowed out) ones on line I've seen. I managed to wrap a very thin tin shim around the shank of the fly cutter and it wedged in OK to work. Such a contraption would make changing other tools and collets a PITA.......in my opinion.........Thanks for reading
 

markba633csi

Gold
Registered
Joined
Apr 30, 2015
Messages
3,573
That's a toughie. Perhaps a plating shop could plate it back? Or spray-plasma and re-grind. Don't know the cost
 
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
How different is the m head to a j head? I have a Bridgeport j head sitting on my garage floor I bought for space parts. I used up all the spare parts I needed and I’m left with an empty head, full pulley drive head, and a decent complete R8 spindle I don’t need. If it’ll fit, I’m sure we could make a deal.
 

Ed ke6bnl

Brass
Registered
Joined
Nov 20, 2014
Messages
551
might be more reasonable to replace the entire head with a J head, I have a round ram with a J head. I got it that way.
 
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
Well... I have a whole j-head. Albiet, missing most of the innards, mostly the quill power feed stuff. The drive head will need to be torn down, it's very stiff. I have not looked at it all. If there's a mild interest in it, I can take pictures.
 

Bob Korves

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Jul 2, 2014
Messages
6,494
Greetings. I have an older round ram, M head Bp mill. The spindle is so worn out inside that my Morse taper # 2 (MT2) collets go all the way up inside almost to their widest end before they clamp the bit. So far I can live with this but it consumes almost all of my bit length. My biggest problem is with a NON COLLET tool, such as my MT2 fly cutter and MT2 keyless chuck. they literally rattle around inside the spindle even when inserted all the way! They wont take any milling load and will simply spin off the drawbar. Any suggestions? If I could find a new M head spindle, I'd just buy it and problem solved. So far only used ( and probably also wallowed out) ones on line I've seen. I managed to wrap a very thin tin shim around the shank of the fly cutter and it wedged in OK to work. Such a contraption would make changing other tools and collets a PITA.......in my opinion.........Thanks for reading
Wait, doesn't an M head use R8 collets? Make sure the serial number has a M at the beginning of it. If it does, maybe try a R8 collet for fit. If it has a H at the beginning of the s/n, then it a H head and you should talk to me about some nice unobtainium collets I have...
 

chips&more

Active User
Registered
Joined
Mar 19, 2014
Messages
2,524
The taper being that worn does not make sense to me. What does is the assumption it has a #2 Morse taper and it probably does not. The M head came with 3 different tapers to my knowledge, a #2 Morse, B&S 7 and a B-3. Sorry Bob, don’t think there was ever a R8 in a M head. I would look again at the taper you have…Dave.
 
Last edited:

Dredb

Active Member
Registered
Joined
Jan 6, 2018
Messages
94
I agree with the last 2 posts, can't see any way the spindle taper could wear like that, it's either been butchered or it's not MT2. In addition to the MT2 and B&S tapers there were also some specials but no R8 on these, the spindle is not big enough. Best thing to do is take a cast of your spindle taper and measure it. A J head would be a nice upgrade for your mill. I use an M head on my non Bridgeport mill, I like it, it's fine but the J head is in a different league altogether.
 

Currahee26

New Member
Registered
Joined
Apr 14, 2017
Messages
22
HMMMM!
Some very intriguing ideas and observations! I'm not sure why I thought/think it's a MT2! I think it may have been the manual I found on it.
It was being used as a drill press and had a non drawbar loaded keyed chuck hammered up into it. (NOT by me!) It didn't even come with a drawbar! I found one on eBay (Maralice ). I've been surmising that the pounding just wallowed out the spindle. Now that I know what B&S #7 (thanks Markba633csi) size is, I will either try and figure out how to take a cast (Dredb) and or find a B&S #7 and see if it fits. I have so many other questions about this mill and its normal functions, but for now Ill address the spindle issue. It had been in the repair shop in Miami Fl at the USOA (US Overseas Airways). They had GREASED it for years and I had to clean all the oiling ways to oil it properly. The left and right movement of the table is sloppy but I have tightened it up as best I can for now. Ill get your advice on that issue later.
Thanks to you all for your time and help.
 

markba633csi

Gold
Registered
Joined
Apr 30, 2015
Messages
3,573
You can hear the machine breathing a sigh of relief: "finally, some people who know how to care for me"
LOL
 

Currahee26

New Member
Registered
Joined
Apr 14, 2017
Messages
22
I replied last night here with NEW FINDINGS, but the post is missing! hmmm Oh well, Ill try again. I re read the manual for the round ram/M head Bp mill and it says that the M head could be ordered with one of three spindles ! Part number 2204820 was a #2 MT, Pn ***4821 was a #7 B& S and Pn ***4822 was a B-3!! So, I'm going to try a #7 B&S collet first and see what happens. I wouldn't have looked up the parts list if it weren't for your suggestions about different sized spindles!
SO< thanks again to all who took the time to reply
dlB
 

Currahee26

New Member
Registered
Joined
Apr 14, 2017
Messages
22
WEll, as it turns out gents, the #7B&S taper fits perfectly! It sticks out of the snout of the spindle almost half an inch more than my MT #2 collets do!
That gives me considerably more force on the clamping and virtually no spin on the fly cutter or drill chuck.
Thank you all again for your time and assistance.
Peace
dlB
 

Currahee26

New Member
Registered
Joined
Apr 14, 2017
Messages
22
Thanks for posting this Link on "M" Head Collet Sizing. VERY informative!! As it turns out my M head came with a spindle that takes #7 B&S collet as I stated in an earlier reply I was able to find as many as I needed on eBay. Just had to search a few sellers "stores" to find the listing but it was easy and not very expensive.

Thank again for all input
dlB
 
[6]
[5] [7]
Top