Sup gents. I'm making a part on my mini lathe that requires

>>1136041
>off to the right
*left

Derp.

Did she dull out on ya?

>>1136054
and/or it's not exactly aligned like OP thinks it is

>>1136041
What metal is the stock and what type of bit are you using? Is the bit properly matched for that type of metal? Getting that wrong just ends in tears.

>>1136041
sharpen the drill

if you dont need all 16 of that drill bit you should just chop it down

it doesnt sound like its being held properly in the tailstock
especially if its just held by setscrews

think about getting 2 drills or shorter drill or something so you can do it in steps like shiort bit medium bit long bit to avoid dulling the really long bit

>>1136054
>>1136141
>>1136128
It's sharp.

The part is 4140 annealed, bit is 118 degree HSS. Again, it's fine, sharp, it still cuts right when it's in the tailstock. I can move the bit into the tailstock chuck and drill into the hole like usual, then move it to the carriage and it doesn't cut, then move it back into the tailstock chuck and it cuts fine.

>>1136124
Possible, but I've lined it up pretty well with a Mitutoyo test dial. I also checked it wasn't moving off center when pressure was applied by pushing it against a little aluminum plate.

>>1136154
I start the hole with a jobber, then move to a regular drill length. When the hole is a good 4" deep I get the long drill bit.

Cutting it down at the shank would help a little, but it still doesn't really do much for the carriage-mounted-drilling-not-working thing.

>>1136041
bent, dulled, or you have some metal galled to the cutting edge.
You'll also save the jobbers bit by using a center bit to start the hole.

>>1136170
Nope, nope, nope, and I started with a #3 combo center drill, jobber drill, then regular drill, then went at it with the long drill.

>>1136169
>>1136170
Ah, ok.
Your tailstock is going to do a good job of sending the force strqight in. the carriage and tool post will deflect, especially on a lathe that light. if you can't get a straight bite in annealed 4000-series... whoo boy. Try a butter knife instead.

>>1136172
>Nope, nope, nope, and I started with a #3 combo center drill
OK, good.
Then the remaining possibility is deflection.

>>1136175
>>1136177
That was also my line of thought, so I tightened the gibs on the cross and compound slides completely (so I can't even move them if I try). The carriage gibs are pretty good, bit less than a thou of play in any direction, that little slop shouldn't matter, but I could be wrong.

>>1136041
Oh, that's one of the tiny Sieg-made lathes. The carriages and tool posts on those are about as rigid as cardboard. They're not awful, just know the limitations. You're just going to bend the bit mounting it like a tool.

>>1136179
it's not looseness in the gibs that's the problem, there's just not enough metal there to keep things from flexing once you add some force. Fundamental limitation of the tool.

>>1136180
>>1136181
[And if you're thinking, "that sucks!" hey, you could be trying to do metalwork on a Sherline. Then you would truly hate life.]

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>>1136184
>you could be trying to do metalwork on a sherline

Tell me about it, I have to build entirely new machines pretty much to get any kind of usefulness out of them.

>>1136180
>they're not awful, just know the limitations
As the owner and OP, I have to say that they are indeed awful. Nothing on the lathe is hardened, ways are butter soft, I've dented them when I dropped a brass rod on them. The cross and compound dovetails are also tapered, so you either have it well adjusted but after an inch or so it seizes up or you have it set with more slop to get the whole 3 inches. The tailstock "quick clamp lever" bends the tailstock body in any and all directions, so lining up the tailstock is impossible when using the quick clamp lever; I've thrown it the fuck across a room and now I just use a nut and wrench, if you use the same torque it's pretty repeatable.

I would not recommend buying a mini metal lathe of any company unless you're stuck between a rock or a hard place in the "I can't have anything bigger" way. I would gladly take a clapped out colchester or hardinge even if half the gear teeth were broken and even if the ways were worn in every direction like ten thou everywhere in random directions, and even if it was just crying rust out of every orifice, but I can't move thousands of pounds of steel in a small apartment up stairs.

>>1136184
Honestly I've shopped around mini lathes and they're all basically identical in how bad they are when doing real work.

>>1136180
>>1136181
Yeah you're probably right for lack of rigidity in the slides/tool post. Shit just doesn't seem like it added up though, I mean it's less than a quarter inch diameter bit, everything is locked down and lined up.

I thought I had lost my surprise for how terrible mini metal lathes are, but I guess I found something new to be surprised about.

>>1136190
>As the owner and OP, I have to say that they are indeed awful.
They're pretty much exactly what you'd expect for the price. I bought one with expectations set accordingly, and it has not disappointed. No hidden gotchas, but no pleasant surprises either. I wouldn't call them good, but I can't call them awful in that the thing has delivered what it was supposed to.
They're a chunk of cheap iron, relatively competently machined into a light duty lathe. No more.

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>>1136193
>They're pretty much exactly what you'd expect for the price
Well I think I thought this particular model (LMS Hi-Torque) would be a bit better. There's a guy on youtube that did like an hour demo, showing it off, and it seemed like it would be quite a lot nicer than the crap I had access to locally.

What sold me on it most of all was the spindle controls for speed and CW/CCW. I have to say that even if there's like half a second of delay between flipping the switch and the spindle doing what you wanted, that it makes single point threading really nice, see webm.

What the videos forgot to mention was everything else.

>relatively competently machined
Maybe I got one made five minutes before quitting time on Friday or something because fuck pretty much everything under the hood is so rough I've gotten a better finish with a corncob endmill, and most of it is so tapered or just off in various ways just to ruin my day when I'm trying to line something up. I've had to take most of the lathe parts to work so I could take a skim off the top because it just doesn't fucking line up.

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>>1136197
That's the exact same Sieg, different color, different accessories.
>Maybe I got one made five minutes before quitting time on Friday
Maybe. I've heard they vary-- the bench mill I got from them was missing a few bolts because whoever was supposed to tap the hole... just didn't. So the next guy didn't bother putting a bolt in. Shipped it anyway.

All these cheap Chinese tools are really just kits. The mills, lathes, laser cutters, whatever... you can polish a pretty shiny turd out of them, but none of them are just ready to go out of the box.

>>1136207
>you can polish a pretty shiny turd out of them, but none of them are just ready to go out of the box.

Another Seig owner here. Can confirm for kit machine.

Mine isn't horrible where it counts; the ways are straight and the machine is a lot more square than I thought it would be (out ~2 tenths/inch). But the ways on the cross slide and compound have garbo fit, especially with the shitty gibs. The tool tends to get pulled forward due to the bad fit there. Had to remove the paint on the lower mating surface for the carriage's gib (which itself I had to lap flat).

Converting it to CNC currently, and discovered the leadscrew was so tight, it was almost impossible to turn by hand. I figured it was a bad fit in the mounts, turns out they were just badly misaligned. Milled out the screw holes for them a little and carefully adjusted them as I tightened them down. Screw now spins so freely you can spin it by brushing your finger against it, yet has almost no slop. Same story for the half nut.

Haven't even done half the things I could to make it decent. Really don't want to put in the work to fix the ways, but, eugh...

>>1136041
>trying to drill a gun barrel on a commutator lathe
if you're going to be stubborn, you're going to have to be patient too.

>>1136235
Wisest words I've heard on /diy/ in a while.

>>1136235
It's not a gun barrel, I have plenty of those already, buying them is a much better idea than making them without a proper gun drill setup and a rifling machine. Both of those are shitton expensive and it would be impossible to get those in a tiny apartment.

I've been detail shy because talking about the part (it's an extended gas key for an LR-300 type rifle) isn't really required for solving the problem at hand. Explaining what the part is, why it needs to be done this way, why can't I just buy one, and so on would also not really solve the issue at hand or really do anything constructive, plus this isn't /k/.

>>1136241
No worries, you gave more detail when asked, unlike most assholes who post here. So you're legit, we're trying to help. Well, I'm trying to help at least, not much I can add tho.

>>1136242
I can understand a lot of people not wanting to talk about shit, even if they're not doing anything illegal, some folk just want to keep their ideas to themselves if they're trying to do something that might make them money.

I do I thank you all for your input, and agree that there's not much to be done. I'll pretty much just have to go on at my current pace with the drill in the tailstock.

Thanks fellas.

>"Parts"
These "parts" wouldn't have to also withstand high pressures?

>>1136689
Technically yes. No, it's not a suppressor or a gun barrel, yes it's /k/ related, but it's not a firearm or anything regulated/controlled.

I got a thread up on OPchan about it (it's on the first page) if you want to read more/ask questions/discuss.