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torker
01-13-2009, 12:22 PM
Hey guys!
Geez..I'm having second thoughts here.
I took the M head off my VN yesterday and was going to make an adaptor to fit it on my Ohio horizontal.
I didn't think it'd be that big a deal but now that I've measured it all up...it's going to be a bigger job than i thought.
I have the 1" thick plate all marked out and ready to cut...
Now I'm thinking...this M head is pretty light...MT2 spindle..need to buy a new motor (old one is 575V). I don't even know if the M head bearings ar ok...no real way to test it other than tearing it down (not an easy job)
The only advantage I can see over my R-8 mill drill is that I'd have the knee to work from.
Can anyone point out any real advantage that I may have missed?
BTW...THE VN is not an option yet...needs it's own new building and it's all 575V also.
Thanks!
Russ

torker
01-13-2009, 05:26 PM
Hmmm..not a lot of support here for the old M head huh?
If it was a J head...I wouldn't have even asked :D It woulda been on there already.
I looked at KBC for an offshore copy of a J. Whew! They want almost as much for a head as they do for a whole Bridgey clone. Yikes!

Peter N
01-13-2009, 05:43 PM
Sounds like you may be better off selling the M Head Russ, and I'm sure there would be plenty of takers if you advertised it in the right place.

Alternatively, as you already have a 1" adaptor plate almost ready, why not make this a 'swivel' plate, find a nice knackered old pedestal drill, and make an M head pillar drill with swivel capacity?
I'm sure it would be more than useful for drilling odd angled holes on some of your fabrication jobs, and MT2 is perfect for that.

Peter

torker
01-13-2009, 05:46 PM
Peter...LOL ! I just happen to have a wornout pillar drill. I'll have to see how it will fit!

x39
01-13-2009, 06:35 PM
I'm not particularly fond of M heads, I really don't know why Bridgeport even continued making them with the advent of the J.

Bguns
01-14-2009, 03:21 AM
The Smaller Quill gets into tighter Places, and No J Head ran 12000 like the High Speed M Head...

Bearings are no Big Deal, And only A Spanner needs to be made to get Spindle Locknut off.

It is a Light Unit, but I have been Plowing thru 3/4 CR Plate with a 1/2 in Rougher..... Making a J Head Adapter :)

I will Put the M Head on my Old #1 Cinc. It will be a good match, Size and Power wise, to rest of Mill...

If You Have It, Use It...

torker
01-14-2009, 08:20 AM
Bguns...Thanks for that!
I asked because I've been reading about the M head....some said you would have a very hard time using a 1/2" drill bit in them...they couldn't take the "abuse".
Seemed rather silly to me. My old Jet drill press often has 1" S&D drill bits in it and it has lasted for 20 years. Nope...it's not stood up well but it's good enough for fab work. The only thing...my drill press does turn slower than the M head.
Still kicking this over.
The Ohio has a bent spindle and another shaft inside...having a verticle head on it would restore a lot of it's capabilities.
The all axis power feed on the old mill are very nice and work well.

LOL! I push my mill drill pretty hard. I don't know if you saw my previous post but I really do cut 3/4" plate....with 1/2" corncobs...full depth passes when cutting slots.
It has enough power to run 3/4" roughers making the same cut if i needed it.
There is no way the M head will do this.
I've seen it reffered to as "The toolmakers" head.
There's a guy from Cowgary who comes here...quasi...I think he has a BP from about the mid 80's that has a factory installed M head.
I guess...in the end...I'll never know unless i try it...
Russ

lazlo
01-14-2009, 09:33 AM
The Smaller Quill gets into tighter Places, and No J Head ran 12000 like the High Speed M Head...

Did the High-speed M-Head have special bearings?

torker
01-14-2009, 10:00 AM
Did the High-speed M-Head have special bearings?
Robert...the little bit of info I've found out about the high speed head...it used a 3600 rpm motor. The regular M head uses a 1200 rpm motor.
I've been looking into a suitable C frame replacement motor...the 1200 rpm is the kicker..I've found 1750 and 3600 rpm motors but would like a 1200 for obvious reasons (slower spindle speeds)
I've seen no mention of special bearings in the high speed head but I'm betting they are a higher spec bearing.
I'll have to ask...I'm almost betting those bearings had preload of somekind...:D

lazlo
01-14-2009, 10:14 AM
I've seen no mention of special bearings in the high speed head but I'm betting they are a higher spec bearing.
I'll have to ask...I'm almost betting those bearings had preload of somekind...:D

That's the reason I was asking Russ -- the Millrite had a high-speed spindle option, but it had a different bearing configuration.

People ask all the time on the PM Bridgeport sub-forum what's the highest safe spindle speed, and the experts there usually recommend a max of 5400 RPM or so...

The Bridgeport uses a pair of light preload 7207's, and according to the bearing manual, a light preload should be good to upwards of 30,000 RPM. I think the reservations may be directed at the other components in the head, but if the stock M-Head can do 10,000 why not the J-Head?

torker
01-14-2009, 10:19 AM
I'm wondering if it isn't because the M head is a far simpler head than a J.
There really is nothing to them.

Bguns
01-15-2009, 01:28 AM
High Speed M Head also used Flat belt...

Torker, put a Little VFD on it, I just helped a Buddy do His M Head VFD on a B&S Mill. You can run belt up a notch or 2 to get some proper Belt Wrap/Power in Steel... You Need a New Motor anyway, Get a 1 hp Surplus C face motor with a Short shaft and weld on extension... And VFD away..

Don't Know about High Speed Bearings, but Have normal Numbers for Factory preloaded proper Angular Contacts if your bearings are Bad. I think they were rated to 12k or so anyway..

The Little Spindle Means Smaller Bearings, meaning they can Spin faster without Bearing speeds getting crazy and Mist oil Lube or expensive Cooling etc...

Will Drill 1/2 just fine, And a Corncob at 1/2 in with 3/4 Depth of cut in Steel will go, just not to Proper Torker Speed :)

I use my Big Cincy for Bigger work, but the M Head Gits er done...

Any Chance of Regrinding you Horiz Spindle Taper in place, to get some use out of it?

torker
01-15-2009, 01:34 AM
Bguns...you got my attention now. It wouldn't be that bad then if i could do that stuff with it.
I'm still needing a motor tho...I would have a devil of a time to power up that 575V motor.
A 3ph 220V/with VFD would be the ticket alright. I'll have to keep looking.

Bguns
01-15-2009, 01:36 AM
I found a 1.5hp one for my J Head at SurplusCenter.something :)
Weighs about the same as The original M Head 1/2 HP US Motor..

Old pic but that is 3/4 Steel there.. Only the straight end cuts were full depth.
Rotary Table did not like Full depth on radius :)

http://i95.photobucket.com/albums/l142/m37b1/snow2783.jpg

M Head rated for 1/2 in Drilling, Old J head 3/4, Late 2J 7/8ths...

M Head rated at 1 cubic inch per Min Milling, Old J Head 1.5, 2J 2.0

Boring Cap M Head 1.5 in(Probably belt wrap limited on Low rpm Belt position......) J, 2J 6.0 in

From M-105H Bridgeport Maual dated 81 .

doctor demo
01-15-2009, 02:35 AM
Hmmm..not a lot of support here for the old M head huh?
If it was a J head...I wouldn't have even asked :D It woulda been on there already.
I looked at KBC for an offshore copy of a J. Whew! They want almost as much for a head as they do for a whole Bridgey clone. Yikes!
Take Your mill/drill head and mount it on the Ohio then put the M head on the mill/drill base and if You have an old beat up radial arm saw You could put together a surface grinder:D .
Don't hate Me Russ , It is all Fast Tracks fault:eek: .

Steve

torker
01-15-2009, 08:25 AM
Steve...LMAO! Nah...I can't allow a radial arm saw in my shop...next thing you'd know...I'd weld my homebrew cutter grinder to the damn thing...then cnc it....and I'd spend the rest of my life making round things into square things...

lazlo
01-15-2009, 08:28 AM
The Little Spindle Means Smaller Bearings, meaning they can Spin faster without Bearing speeds getting crazy and Mist oil Lube or expensive Cooling etc...

That's a really good point. The Dumore toolpost grinder spindles have a pair of opposing 7203's (angular contact bearings) and they go up to 30,000 RPM.

torker
01-15-2009, 08:33 AM
OK...you guys talked me into it. I'm moving the Ohio into the machine room today (Yes dockrat...It'll fit :) ) and I'll go ahead and mount up the M head...kinda fitting anyway...an M head on a 1930 mill!
Russ

wierdscience
01-15-2009, 08:39 AM
An M head is also nice and small,perfect for mounting to a lathe cross slide later.

wierdscience
01-15-2009, 08:50 AM
but if the stock M-Head can do 10,000 why not the J-Head?

I know some one who tried to wring 10k out of a B-port spindle.The splined end of the quill shaft turns into a wet noddle and any vibration turns it into an egg beater inside the drive spline bore.The drawbar head lacking precision runout doesn't help either.

It ran nice and quiet with the quill run all the way down(maximum support at the top of the spline) with the quill all the way up it sounded like a limb shredder.

lazlo
01-15-2009, 08:53 AM
Ah, thanks Darin -- that makes sense. I think you know why I'm asking about this :)

MickeyD
01-15-2009, 10:06 AM
When I had a 2J cnc machine the spindle would warm up noticeably if I ran it over 4500 rpm for any length of time. I suspect they used grease packed vs. oiled bearings.

wierdscience
01-15-2009, 10:50 PM
Ah, thanks Darin -- that makes sense. I think you know why I'm asking about this :)

Is a B-port about to be overclocked?:)

wierdscience
01-15-2009, 10:58 PM
When I had a 2J cnc machine the spindle would warm up noticeably if I ran it over 4500 rpm for any length of time. I suspect they used grease packed vs. oiled bearings.

Most of the older 2j heads I am familiar with had oil bearings.Just no way to keep the oil in and no way to get oil up in the top set nor the upper bearing,basically a total loss system.It was an oil daily item and IIRC those heads had a 90* Gitts oiler dead center the quill bore near the top.When it was filled it dropped a few drops down the top of the quill.

Later models went to grease,since greases had improved.I have always wondered what some polimide seals and a some turbine oil would do.

torker
01-18-2009, 02:34 AM
Well that was long night! I'm building the adaptor plates to put the M head on the ol' Ohio.
I think it's going to be a good addition....of course I'd far rather have my VN in there but it'll never even come close to fitting in there.
I'm hoping to have something worthwhile for pics in a day or two...lotta heavy milling.
My interest in the old machine has picked up considerably since i moved it into the machine room. A LOT cleaned environment than out in the dusty old fab shop.
I almost hated using it out there...took forever to clean the fine grit that always got into it before I could use it.
And I've dreamt up a crane for it...an overhead that will lift the dividing head and will also lift the M head off when I need to use the overarm support.
I'll keep you posted as I progress.
I have to miss some machine time tomorrow...well i think i better.
The misuss is coming home from Vegas tomorrow.
I'm sorta thinking she may be just a bit choked if I don't go pick her up :D
Russ

doctor demo
01-18-2009, 03:30 AM
.
I have to miss some machine time tomorrow...well i think i better.
The misuss is coming home from Vegas tomorrow.
I'm sorta thinking she may be just a bit choked if I don't go pick her up :D
Russ
You could send the Gurl to pick her up:D . Oh and by the way Russ you do know ''what happens in Vegas stays in Vegas'':eek: .

Steve

torker
01-18-2009, 08:19 AM
LOL! Nope...the gurl is running dayshift at the motel. Steve...it's "MEXICO"....

doctor demo
01-18-2009, 02:52 PM
LOL! Nope...the gurl is running dayshift at the motel. Steve...it's "MEXICO"....
Russ I think You need some time off in post#25 You said ''Vegas'' and now You say Mexico.
Vegas or Mexico, You better take some warm clothing to the airport with You. It aint gona be 85 deg. out like it was when she got on the plane:eek: .

Steve

torker
01-18-2009, 08:28 PM
Steve...LOL !...I meant the song..."What happens down in Mexico...stays in Mexico" (Toby Keith)