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Made my first tiny parts. Have some questions....

CVRIV

Aluminum
Joined
Feb 19, 2021
There's no measuring dial on the large hand wheel used to move apron in the x direction. How do you measure movement in the direction?

Do ya'll even use the dials?

I made some tiny washers and just used a dial caliper to messure the diameter of the part. I also used the depth gauge portion of the dial caliper to measure each cut-off or parting of a washer. Is that usually how its done?

I wanted the washers to be 1mm thick, but they're about 1.1mm thick which fine for me right now.

I drill the aluminum rod out using a 5mm drill bit. The hole is a little larger. The holes are about 5.5mm while the shaft of the drill bit is only 4.9mm. I aligned the tail stock the best i could so it dead center. I placed a dead center in thevmain shaft and another center in the tail stock. I aligned the point so that they were nearly perfectly pointed at each other.

The drill bit has to be walking while cutting. How to stop it? I appear to have an equal amount of chips in each flute.

Thanks.

0508211939a_HDR.jpg
 
You can stick a magnet base dial indicator on the front of the ways near the chuck and watch the dial as the carriage pushes on it. A travel stop can also be used to stop the carriage in the same spot every time. Other ways are a trav a dial on carriage, or a DRO....
 
You can stick a magnet base dial indicator on the front of the ways near the chuck and watch the dial as the carriage pushes on it. A travel stop can also be used to stop the carriage in the same spot every time. Other ways are a trav a dial on carriage, or a DRO....

I have a travel stop. Im going to have to figure this one out. Thanks for the input.
 
The parts look good man good job

Thank you. I bought a bench grinder, with a nice stand, to touch up some of the tools that were already ground. Once I shaped then nicely, the lathe cut soooooo much better. Kind if addicted now.
 
I drill the aluminum rod out using a 5mm drill bit. The hole is a little larger. The holes are about 5.5mm while the shaft of the drill bit is only 4.9mm. I aligned the tail stock the best i could so it dead center. I placed a dead center in thevmain shaft and another center in the tail stock. I aligned the point so that they were nearly perfectly pointed at each other.

The drill bit has to be walking while cutting. How to stop it? I appear to have an equal amount of chips in each flute.

Thanks.

As you have just found, drills are terrible for making accurate holes. Generally, when I need to make an "exact fit" hole I will drill it under sized and then use a boring bar to take it to size.

JMHO

-Ron
 
Lock the carriage, set the compound rest to 90* and away you go.

Carriage stop or indicator for repeated passes on larger parts.

Use a purpose-made center drill to start the hole. They are made very hard (and brittle) to resist walking. Change to a small twist drill to make a pilot hole. Step up to your final size or just under. Finish by boring or reaming.

Careful with reamers - they're precision tools and it's easy to ruin their accuracy if misused. Never back them out. Always spin them forwards.

Blue sharpies and scribes (or a little 'kiss' with whatever tool you have set up) are your friends on old non-DRO lathes.

Calculate, cut a little shy, measure the error, recalculate and dial in your final cut. Be aware of tool spring and the effect more aggressive cuts will have on it. A deep cut will tend to be a thousandth or three shy of what you actually dial in depending on your tool/machine rigidity and material hardness - whereas a light finishing pass will normally be dead on or pretty close. This effect can invalidate your final measurement and dial-in if you're not mindful of it. E.G. dialing in 12 thousands after a heavy cut with 1-2 thousandths of tool deflection will result in a final cut of 13-14 thousandths - a big deal if you're boring for a press-fit.
 
There's no measuring dial on the large hand wheel used to move apron in the x direction.

Do you mean Z axis?
SB's all have dials for x unless somehow yours is missing?


How do you measure movement in the direction?

As addressed by others, also....

Use a stop, use the micrometer on the stop, and use (gage) blocks, shims, or micrometer standards between the stop & the carriage.
Long travel dial indicator or dial or digital caliper fixed to ways as other mention.

Do ya'll even use the dials?

Yes.
But gross/large measurements checked in process with mics.
Most of us are driving old SB's with well worn leadscrews. :)
Be sure to take the slop out in the same direction each time, too, of course.

I made some tiny washers and just used a dial caliper to messure the diameter of the part. I also used the depth gauge portion of the dial caliper to measure each cut-off or parting of a washer. Is that usually how its done?

That is a little less positive, but if it works, it is one correct method.
They look very nice.

I drill the aluminum rod out using a 5mm drill bit. The hole is a little larger. The holes are about 5.5mm while the shaft of the drill bit is only 4.9mm. I aligned the tail stock the best i could so it dead center. I placed a dead center in thevmain shaft and another center in the tail stock. I aligned the point so that they were nearly perfectly pointed at each other.

Read some of the many postings, probably in the rebuilding and scraping forum, about aligning light lathes, including twist in the ways. Also aligning the TS. There's too much, posted too often, to repeat here.

as a short-cut, put a test bar between centers, and indicate it at each end.
Alternately and to determine dynamic conditions, put a piece of scrap between centers, and reduce the middle portion of the bar "somewhat". Then turn smooth ring at the headstock end, and without changing anything, one at the TS end. Measure, & compensate.

The drill bit has to be walking while cutting. How to stop it? I appear to have an equal amount of chips in each flute.

Even small scratches in the end of a bar can catch and displace a drill with any slenderness ratio.
As others mention, always use a center drill first.
With a center drill & a drooping TS, the actual drill may appear to step up as it enters the C-drilled hole. This is as it should - given the conditions it is finding the actual center of rotation even though being presented off-center. But from that point, it should not wobble or walk. It will drill more or less oversize, and more or less bell-mouthed if measured with equipment that can detect the conditions. Also as Conrad mentions, single point boring will cure it and is used for accurate work.

For work similar to yours, a chucking reamer can be faster than boring. The long shank defelcts as does a drill, so the reamer centers in the drilled hole. For short lengths of work even if the TS condition is not ideal, the reamer will make a round hole on size. Deeper holes, it can still bell-mouth if the TS barrel center/tooling is not aligned in both horizontal & vertical planes.

Your work looks nice, you must be doing most things right.

:)

smt
 








 
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