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7.5H.P., 1 13/16 dia. thru A36

Greg White

Titanium
Joined
Jan 22, 2007
Location
Pinckney Mi.
I might be looking at 300 holes 1 13/16 dia. thru 1 3/4 thick A36 burnouts, 6holes per pc.
Matsuura, BT40, 1987 year built, no tsc.
I am asking for suggestions on tooling?

1/2 pilot drill,stuff a twist drill after it?

H.S.S. spade drill into solid?

I dont think I want indexable carbide drill? not enough H.P.?
not lookin for super fast, more steady and reliable.
How should I have it?
Gw
 
If you have a geared spindle get after it with the drill.

Might try a 3/4 variflute solid carbide with at least a .03 radias and pocket them.
 
I drill 1 1/2 holes in a36 all day with an insert drill and 5hp K&T vert mill old as dirt. I run it at 250 rpm and hand feed it, I can make a hole in under a minute with no pilot hole. the mill doesnt even struggle.
 
I drill with a 1 13/16 insert drill on my Matsuura 710 all the time but it is a gear head
 
Its a gear head,mine is a 800.

Gw


You can add a coolant inducer toolholder that you would have to retrofit to your spindle cap, or you can go with a BT to Morse Taper toolholder, and then get a Morse taper holder from Allied. The MT holders have provissions for a Rotary Inducer on them.

I used this trick on some 1-3/16" holes in 4140 on a 5hp geared head mill a few yrs back. I ran the tool through the changer and added M0's on both sides of the process. At M0 I would simply hook up a hydraulic quick connect (Pioneer brand - get at your Johnny Deere (or other color?) dealer) and I tossed a stack pump in the coolant tank that would build some decent pressure, and unwired the chip conveyor and used that for the pump. So I would hook up the hose, push go and push the start button for the pump. When done, shut the pump off and take the connector loose, and push GO and it would change the tool and continue with the rest of the program.

Actually I had two differ'nt drills like that on that part. Worked great - other than you had to be there to hook it up and unhook it...

I would think that you could pull a 1-13/16 with a 7.5/gear in A36.

That was on this block - used as a shot pin assy on the 50 cal turret on top of one of the Navistar trucks sent to the sandbox.

NavistarMRAP.jpg



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Think Snow Eh!
Ox
 
I visited a friend who works at a shop that makes structural parts for bridges, and they also have an old Matsuura 800 VMC. They were running a job that was 1-3/4" thick A36 steel, needing 1-7/8" wide x 5" long slots through the plates. The way they were doing it was to use a Walter B4212 insert drill (2xD) to punch a hole at each end of the slot, then drill through the web at the center of the slot. That last hole was an interrupted cut, so I was surprised at how the drill held up making that third hole though they did slow the feed rate to 1/2 the rate of the fully round holes. After the three holes, in with a 1-3/4" multi-insert milling cutter to interpolate the final size.

That machine also has no coolant through spindle but I guess it worked ok being a 1:1 ratio depth. Plenty of flood coolant seemed to work just fine. I wouldn't worry about needing coolant through the spindle with a hole that less than 2xD as long as the flood coolant is effectively flushing chips out.
 
If you will be babysitting it what about an annular cutter? I would be leery of one if you were not babysitting it in case the plug didn't pop out. But I have been amazed at how fast I can drill nice clean larger holes using my 3hp manual mill with them.
 
the parts won,t
be sand blasted nor normalized,so the tourch slag would be nasty.

Ox ,cause you said Allied I am ass suum ing your suggesting a single shot thru with a spade drill?

Well where would you start for rpms and feed per rev. @ 1 13/16 dia.? Clear for bolts.
They are gonna be round like a weld on pipe flange,maybe 18" od,donna know id.

MSC ,spade tip and holder cheaper than a good twist drill...
Thanks guys for thinkin wit me
Deathly afraid of a annular cutter, i like gravey, Iam buds wit the owner.
don't want to buy a indexable, to stressful now Iam a senior.
Gw
 
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the parts won,t
be sand blasted nor normalized,so the tourch slag would be nasty.


Which is why you would conventional mill the holes, rather than climb mill, so that the cutter teeth are actually cutting under that slag rather than coming down on top of the slag. I've done this for years and it works great.
 
I hear you Dave, the burn outs are being supplied without holes to me, more work for me?
Cutter still gotta bust thru slag to get started,iffin I had to I would of course doit.
Gw
 
I hear you Dave, the burn outs are being supplied without holes to me, more work for me?
Cutter still gotta bust thru slag to get started,iffin I had to I would of course doit.
Gw

I understand, Greg. It only pokes through momentarily though, and is nothing for a carbide end mill. But, if they are being supplied to you by someone else, you gotta deal with what you got. Personally, I think a spade drill would be working pretty nice for ya, if you have the torque for it.
 
Ox ,cause you said Allied I am ass suum ing your suggesting a single shot thru with a spade drill?

Well where would you start for rpms and feed per rev. @ 1 13/16 dia.? Clear for bolts.
They are gonna be round like a weld on pipe flange,maybe 18" od,donna know id.

Gw


"By the book"

S=130-240SFM depending on which insert and hardness. (HSS/Cobalt - not carbide)
F= .018

I usually run on the low side of the S range just b/c I baby my tools as a rule, but ....

I really didn't follow the rest of the question?
"Burnout" aint flat?


BTW - I would agre that you could likely be fine with a stuby drill with no coolant through for such a shallow hole.
I was just offering an idea how to give you the coolant option on your machine.

---------------

Think Snow Eh!
Ox
 
OX cant you see my print?:) (I dont know how)
18 inch dia. with maybe 12" idX1 3/4 thick, big washer 1 3/4 thick, I am drillin thru 1 3/4 on a B.C. eh?

Yes on the vert. 16,000lbs worth 1987 Matsuura, bt 40 taper,7.5 H.P. 2 speed gear box, I want to(iffin its rite) to use a spade drill ,no pilot hole,seems the cheapest route???? aint lookin for the fastest(indexable Carbide inserted drill,no)
thanks again, I am all ears here folks
Gw
 
I take it that there is some tongue-in-cheek in your "print" statement?
No - I don't see no stinkin' print...

I ass_u_me that you have 25-26" of daylight under the spindle?

18" part?

The shortest holder that I can come up with is:

Allied drill body #21030 is a "Stub Length" holder, but has a 1.500 strait shank.
It has an OAL of 7-39/64"
with an under the shank dim of 4-59/64"

The shank is 2-11/16" long x 1.500 diameter.

http://www.alliedmachine.com/searchResults.aspx?itemNumber=21030s-150f

Guessing that you don't have room for a 3" projection BT holder, you could turn the shank down to 1" and use a stub length BT holder.

OR - I called AMEC to see if they offer anything better suited, and they said that they could turn the shank down to 1" as required for you.

There would be a "center" (1/4" pipe tap) in the shank that a guy should be able to stuff it in the lathe (OD grinder?) and peel away. That will only leave you a >1/4" wall so you may want to feed on the low side?

I don't think that you can get a 1-1/4" stub length holder in the "BT-40" size?


If you have 30" of daylight under your spindle, then you can prolly go with standard tooling.



I dont think I want indexable carbide drill? not enough H.P.?

You don't think that you could pull that?
They cut free'er than a spade. Of course you wouldn't have the help of the gear-box like you would the spade...

???


18 inch dia. with maybe 12" idX1 3/4 thick, big washer 1 3/4 thick, I am drillin thru 1 3/4 on a B.C. eh?

B.C. ???
Between Centers?
British Columbia?

Are you puting one hole/part, or making swiss cheese outta this thing?



A Google pulled up limited hits on BT40 Stub 1.25", but it is listed here:
http://www.basstool.com/PDF/CATALOG/1052-1113.pdf



Briney (Bad Axe, Mich) lists a BT40 1.25 shank x 2" guage length. (At least near as I can tell from their web page)
https://mrc.geminigroup.net/apps/MRCBRINEY.I01102s?slnk=1&WIPRDL=37

A stub length will still prolly be a 1" guage length?



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Think Snow Eh!
Ox
 
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