Heavy thread cutting on light lathe

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

Bentwings

Well-Known Member
HMEM Supporting Member
Joined
Jun 18, 2020
Messages
879
Reaction score
136
Location
Minnesota
Please understand my comment about the CNC had nothign to do with modern machinery, but the method applied to achieve equal cutting forces on each pass. My 10" Clausing 4900 struggled to perform when the bearings became loose. Fortunately, it uses taper rollers and correcting preload was simple.
When doing some of the stuff we do in our little home shops with light tools and machines it’s necessary to finesse things and not do massive cuts that even a little larger equipment is capable of. Most of us have been in shops where chips are hauled around the shop in 55 gallon barbells by fork lift or heavier moving things. Instead of a barrel we might have an old cereal bowl for chips , toss them in the recycle trash can. Drilling and tapping an m 2 screw thread as an example in some brass flat stock . . Getting piston rings seated in a tiny bore . I’m running into this issue too. I know exactly what I need but conveying my needs to my boys is some times hard . The chip is not much bigger than my kitty fur. A days scrap fits in a sandwich bag.
I’m sure everyone has shop stories of nightmare projects . Cnc has made many things easier no doubt but it still takes knowledge of how to make things large or small.

Byron
 

Lloyd-ss

Well-Known Member
HMEM Supporting Member
Joined
Mar 8, 2019
Messages
284
Reaction score
159
Location
Charlottesville, VA
It is very helpful to see so many different suggestions for a single challenge. Often, we are trying to get our machines to do things that they never were supposed to be able to do. I have always said that knowing the "tricks" is the secret. Some we learn ourselves, others, are graciously shared by other members.

On my bench top grizzly lathe, for very heavy work, or interrupted cuts, I made a solid steel block tool post that temporarily replaces the compound and gets rid of an amazing amount of chatter. I don't use it very often, but when I need it, it sure is nice.

Another thing that I do for threading, and I know this will make some of you cringe and shake your head, but if I have to cut a few identical large inside and outside threads, that must be interchangeable and precise, I will order a matching tap and die from China. They are reasonably inexpensive on ebay. Then I machine the threads to within a few thou and only use the tap or die to do the final cleanup to bring the thread into size, give it a pretty finish and profile, and finish the root and crest. Honestly, it gives me some peace of mind knowing that the thread is correct, especially on heavily loaded parts.
 
Joined
Apr 2, 2020
Messages
2,678
Reaction score
810
Location
Sunderland , UK.
I bought a set of thread chasers for finishing machined threads. They will not cut 95% of the metal out but will finish to the finished thread profile better than I can do otherwise. Try Tracy Tools in Dartmouth, UK, for thread chasers...
K2
 

Bentwings

Well-Known Member
HMEM Supporting Member
Joined
Jun 18, 2020
Messages
879
Reaction score
136
Location
Minnesota
It is very helpful to see so many different suggestions for a single challenge. Often, we are trying to get our machines to do things that they never were supposed to be able to do. I have always said that knowing the "tricks" is the secret. Some we learn ourselves, others, are graciously shared by other members.

On my bench top grizzly lathe, for very heavy work, or interrupted cuts, I made a solid steel block tool post that temporarily replaces the compound and gets rid of an amazing amount of chatter. I don't use it very often, but when I need it, it sure is nice.

Another thing that I do for threading, and I know this will make some of you cringe and shake your head, but if I have to cut a few identical large inside and outside threads, that must be interchangeable and precise, I will order a matching tap and die from China. They are reasonably inexpensive on ebay. Then I machine the threads to within a few thou and only use the tap or die to do the final cleanup to bring the thread into size, give it a pretty finish and profile, and finish the root and crest. Honestly, it gives me some peace of mind knowing that the thread is correct, especially on heavily loaded parts.
I bought a set of thread chasers for finishing machined threads. They will not cut 95% of the metal out but will finish to the finished thread profile better than I can do otherwise. Try Tracy Tools in Dartmouth, UK, for thread chasers...
K2
using a tap as threading tool has been very popular on small lathes it was a trick I used on my early entry into tool making . I had a 2-56 thread on stainless steel right in the middle of sbout 4” long shaft. I had to make a special follower rest that telescoped as I went down the threads then there was the bating nut or internal threads be though the lathe was a brand new Harding tool room lathe with all the attachments it was a real trick to make these parts . They were a poor design in the first place . The company had been having them made outside at rediculous price . The manufacturing meeting was my almost first go around at being the subject of discussion. I was no champion of debate so things got hot criticizing the head of engineering , but it was a successful solution at the time.

It’s always interesting to see what others do in difficult situations using tools beyond their design intent is not a fault try not to get hurt in the process.. I’m in the misfile of a nasty little fix on my new steamer. Too pushing our small lathe and mill to the limits seems like daily thing. However it certainly brings out creativity. It’s realy nice when my young grandson does some work around. I don’t discourage it at all. He has done some neat things with less than optimum equipment.

Byron
 

awake

Well-Known Member
HMEM Supporting Member
Joined
Sep 4, 2019
Messages
1,739
Reaction score
741
Location
North Carolina
Another thing that I do for threading, and I know this will make some of you cringe and shake your head, but if I have to cut a few identical large inside and outside threads, that must be interchangeable and precise, I will order a matching tap and die from China. They are reasonably inexpensive on ebay. Then I machine the threads to within a few thou and only use the tap or die to do the final cleanup to bring the thread into size, give it a pretty finish and profile, and finish the root and crest. Honestly, it gives me some peace of mind knowing that the thread is correct, especially on heavily loaded parts.
No cringing here - I do the same thing at times, especially for smaller thread sizes.
 

Bentwings

Well-Known Member
HMEM Supporting Member
Joined
Jun 18, 2020
Messages
879
Reaction score
136
Location
Minnesota
Both you and your grandson are lucky. He will always remember these good times with his grandpa.
speakilg of using tools beyond normal function, I’d like opinion of this.
I have a small drill press that has a remarkable spindle. It has as near as I currently can measure no real looseness or run out . I’ve not seen anything like this. It has had very little use . 5 speed step pulleys near new belt. Tilt table round column. 1 hp. I have an X Y table that is very good again no real play and it dials smoothly nice clamp kit new.
I have very limited space roughly half a kitchen table. So I’m looking on internet and found a indexing rotary table with small 3 or 4” chuck. It tilts and has a tail stock. I won’t be doing any production work just “ need it now” hobby stuff most of what I would ever make could be made in 1 cu ft of space beyond machine . Maybe including machine. . Threads I can drill and start. I think I could cut grooves even cut off with slitting saws. I might have to make or purchase an arbor . I can mount a small machinist vice for work holding. Initial test shows reasonable cut with 4?flute 1/4” end mill . I tried a carbide burr and it will cut aluminum with tap magic oil problem .drilled 1/2” hole through 1x1 1/8 wall steel tube without complaining. There are powered rotary table but I think that might be out of range. Cost and usefulness . I simply can’t have a lathe and or mill. There just is not enough room . My boiler project has to remain at my sons shop as I won’t have equipment for it other than what this proposed thing can handle. The rotary table is pretty reasonable and has good reviews. I’m projecting being able to do very light round work, possibly adding my own motor drive to the rotary. It won’t be programmable. I should be able to do minor mill type things maybe mill flat on round shaft drill even bolt patterns . No cnc plans . The way I see this is it hinges on how good the drill press really is typically these are far from very good at all . I’ve done some work on 50 yr old worn out craftsman drill press that amazed me. Most of what I’ll do is modifying something with few made from scratch items nothing complicated or close tolerance . Rc model plane parts are often hard wood. . I can get an aluminum tool plate for a custom table if necessary .

Part of me just says sen stuff out and have someone else do it but then it’s not a hobby

So what do y’all Think? Another nut case ? Better off taking a nap? I what

Byron
 
Last edited:

ShopShoe

Senior Member
Joined
Oct 1, 2010
Messages
1,236
Reaction score
318
Bentwings,

There's been a lot of discussion about using a drill press as a mill. It all seems to boil down to what holds the cutter you want to use.

If you have other than a drawbar retaining your tooling, there is a risk that it will come loose under the side stresses of moving the work past the cutter. Or, it can at least wobble around and give very imprecise results. To repeat, the drill press is for applying downward force to drill a hole. (Unless you are talking about specialized milling drill presses or mill/drills which cost as much or more than a milling machine.)

I have used a rotary table and a cross-slide vise on my drill press, but only for setting the workpiece for the locations where I wanted holes drilled. I did put an endmill in the drill chuck one time to try to cut a slot and the taper-mounted chuck promptly came loose: It was scary, but I was saved by the fact that the endmill through the slot I was cutting in an aluminum electronics housing kept it from flying free.

You can drill holes with a mill, you can mill with a lathe when you have a milling attachment. Generally combination lathe/mill machines are less desirable, but you can use one if you have extreme space limitations. It is up to you to decide what to do.

--ShopShoe
 

Bentwings

Well-Known Member
HMEM Supporting Member
Joined
Jun 18, 2020
Messages
879
Reaction score
136
Location
Minnesota
Bentwings,

There's been a lot of discussion about using a drill press as a mill. It all seems to boil down to what holds the cutter you want to use. Thank you I do agree I’ve not had good luck using drill press outside of it envelope . I did work in a repair shop that had a really big radial drill it had an X Y table that was used in red rolling repaired stuff and some milling but it did have draw bar. I’ve not seen collets or even drill chucks as large as this thing had . It was a brute of a machine . I YHINK it came from the railroad car shops or mining industry . I don’t remover how big the motor was but it was very big. It had a vee block , an adjustable angle table and cube block all took a pretty big fork lift to move around.

Byron

If you have other than a drawbar retaining your tooling, there is a risk that it will come loose under the side stresses of moving the work past the cutter. Or, it can at least wobble around and give very imprecise results. To repeat, the drill press is for applying downward force to drill a hole. (Unless you are talking about specialized milling drill presses or mill/drills which cost as much or more than a milling machine.)

I have used a rotary table and a cross-slide vise on my drill press, but only for setting the workpiece for the locations where I wanted holes drilled. I did put an endmill in the drill chuck one time to try to cut a slot and the taper-mounted chuck promptly came loose: It was scary, but I was saved by the fact that the endmill through the slot I was cutting in an aluminum electronics housing kept it from flying free.

You can drill holes with a mill, you can mill with a lathe when you have a milling attachment. Generally combination lathe/mill machines are less desirable, but you can use one if you have extreme space limitations. It is up to you to decide what to do.

--ShopShoe
 

SmithDoor

Well-Known Member
Staff member
Global Moderator
Joined
Feb 12, 2009
Messages
1,462
Reaction score
232
Location
Clovis Ca
The lathe-mill combo has place like small place and on a ship.
I have small bench Chinese bench drill/mill that works great after some rework. Surprising how well works too.

Dave

Once upon a time I had a lathe-mill. After several years banging my head on the mill-head it finally dawned that for me this is not a desirable combination machine.
 

ajoeiam

Well-Known Member
Joined
Aug 14, 2020
Messages
639
Reaction score
184
Location
blank (like some others I've noticed)
Bentwings,

There's been a lot of discussion about using a drill press as a mill. It all seems to boil down to what holds the cutter you want to use.

If you have other than a drawbar retaining your tooling, there is a risk that it will come loose under the side stresses of moving the work past the cutter. Or, it can at least wobble around and give very imprecise results. To repeat, the drill press is for applying downward force to drill a hole. (Unless you are talking about specialized milling drill presses or mill/drills which cost as much or more than a milling machine.)

I have used a rotary table and a cross-slide vise on my drill press, but only for setting the workpiece for the locations where I wanted holes drilled. I did put an endmill in the drill chuck one time to try to cut a slot and the taper-mounted chuck promptly came loose: It was scary, but I was saved by the fact that the endmill through the slot I was cutting in an aluminum electronics housing kept it from flying free.

You can drill holes with a mill, you can mill with a lathe when you have a milling attachment. Generally combination lathe/mill machines are less desirable, but you can use one if you have extreme space limitations. It is up to you to decide what to do.

--ShopShoe

Well - - - - if you look at older boring mills - - - - they ALL used taper shank tool holding systems - - - - NO drawbar!!!
Now these aren't the boring mills from the 80s and the 90s but if this system was used for some at least 50 years (30s to the 80s) - - - - hmmmmmm - - - - why is it NOT possible to use similar today?
 

ShopShoe

Senior Member
Joined
Oct 1, 2010
Messages
1,236
Reaction score
318
ajoeiam,

I think you do have a point. I did use a drill press with a morse taper and morse taper drill bit one time in my life and it was a diffrent experience than a more recent machine. My bad experience was with a drill press with a jacobs taper holding a chuck in which I installed the endmill. I was referring to a machine similar to the latter example in my earlier post.

It boils down to what an individual wants to do in his or her own shop. That individual is the only one who knows what his own machines and abilities can truly handle. As always: "Your Mileage May Vary."

--ShopShoe
 

SmithDoor

Well-Known Member
Staff member
Global Moderator
Joined
Feb 12, 2009
Messages
1,462
Reaction score
232
Location
Clovis Ca
The spindle on the drill press is different. The Morse tapper is below the bearings. A mill spindle is in quill.

Today's Chinese drill press have Morse tapper in the quill must like a BridgePort mill.

I would not say a drill press is same as a good mill but will job. But a Bridge Port mill is a light mill too and has own problems over a good heavy duty mill.

I seen photo of a few good drill press mills from 1950's and 1960's.

Most stop doing this conversion since low cost mills from China.
As prices go up this conversion will comeback.

Myself I started will milling attachments on my lathe for years.
It work great for keyway milling.
Milling keyway and a few types milling can be done in Aloris Tool post too.

Dave

ajoeiam,

I think you do have a point. I did use a drill press with a morse taper and morse taper drill bit one time in my life and it was a diffrent experience than a more recent machine. My bad experience was with a drill press with a jacobs taper holding a chuck in which I installed the endmill. I was referring to a machine similar to the latter example in my earlier post.

It boils down to what an individual wants to do in his or her own shop. That individual is the only one who knows what his own machines and abilities can truly handle. As always: "Your Mileage May Vary."

--ShopShoe
 
Last edited:
Joined
Apr 2, 2020
Messages
2,678
Reaction score
810
Location
Sunderland , UK.
I have a cheap mill-drill, and simply it isn't a "proper job"... But for light cuts, with care and attention it can be made to do a very good milling job. As a bench drill, it is as good as any I have used.
But it is well worn ( previous 2 owners forgot the slides need lubrication, I guess!).
Maybe one day I'll replace it with something better, but as I have just enough space for that, and it becomes the bench when not in use, then maybe when I move to a bigger house/workshop.... (Sometime, never?).

K2
 

L98fiero

Well-Known Member
HMEM Supporting Member
Joined
Oct 18, 2013
Messages
344
Reaction score
129
Location
Keswick, Ontario
Well - - - - if you look at older boring mills - - - - they ALL used taper shank tool holding systems - - - - NO drawbar!!!
Now these aren't the boring mills from the 80s and the 90s but if this system was used for some at least 50 years (30s to the 80s) - - - - hmmmmmm - - - - why is it NOT possible to use similar today?
The 1950s 100mm HBM I ran had a #5 Morse taper and no drawbar but it did have a locking wedge that fit in the extraction slot, the step up to the new HBM with ISO40 tooling was a huge improvement.
 

Bentwings

Well-Known Member
HMEM Supporting Member
Joined
Jun 18, 2020
Messages
879
Reaction score
136
Location
Minnesota
ajoeiam,

I think you do have a point. I did use a drill press with a morse taper and morse taper drill bit one time in my life and it was a diffrent experience than a more recent machine. My bad experience was with a drill press with a jacobs taper holding a chuck in which I installed the endmill. I was referring to a machine similar to the latter example in my earlier post.

It boils down to what an individual wants to do in his or her own shop. That individual is the only one who knows what his own machines and abilities can truly handle. As always: "Your Mileage May Vary."

--ShopShoe
I’ve seen a couple people have used the jacobs taper I YHINK there is a collet holder too . The issues seems that if you are doing something with vibrating tooling like a hole saw or did cutting end mill in drill chuck the chuck falls out just when you need it. The fix I’ve seen was to drill though the spindle wall tap it some convientvdize snd use it as a set screw . Grind a flat on the jacobs shank . I saw one with a brass point but most use a grade 8 socket head screw or bolt I’ve had the chuck fall out on old craftsman drill presses generally guys smash the chuck in often with a heavy brass hammer . The drill press I’ve inherited has jacobs that is stuck . It’s probably rusted. Actually a dowel pin runs pretty true for a drill press and jacobs drill chuck . It had a drill bit stuck in it I finally got a good chuck key and got it out but the chuck is pretty rough . Again probably rust . I can now at least clean it. I don’t have a chizzle that I get the thing out with yet but my son did he would bring one over . Then I’ll look at what’s there snd what is available I may do the drill and tap thing as the spindle doesn’t seem very hard. . That thin lock tite I have may work to stick a new chuck or arbor in . It wicks like super glue so I may warm .
Byron
 

SmithDoor

Well-Known Member
Staff member
Global Moderator
Joined
Feb 12, 2009
Messages
1,462
Reaction score
232
Location
Clovis Ca
I have had few tools like over the years . I just scrape the bed ways and back to new again with oil now.

Dave


I have a cheap mill-drill, and simply it isn't a "proper job"... But for light cuts, with care and attention it can be made to do a very good milling job. As a bench drill, it is as good as any I have used.
But it is well worn ( previous 2 owners forgot the slides need lubrication, I guess!).
Maybe one day I'll replace it with something better, but as I have just enough space for that, and it becomes the bench when not in use, then maybe when I move to a bigger house/workshop.... (Sometime, never?).

K2
 

Latest posts

Top