Please recommend some places to get stock.

[ShineOnYouCrazyDiamond]

yeppers - thanks for the warning. I think I just experienced that twice. I've been doing okay turning the C145 but just tried to part it with HSS parting tool. It grabbed the rod and nearly ripped it out of the jaws.

I can't tell if it grabbed on the side or dug in.

Now to go and buy some new fuses........

Any tips for the copper parting? Best l liquid/oil to use and how much and often to add while parting?

 

[calipsoii]

Any tips for the copper parting? Best l liquid/oil to use and how much and often to add while parting?

Afraid not, perhaps Barry can chime in or something. I was working C101 (no CuTe available) and after that terrifying experience I refuse to work with it anymore. Parting off is terrifying enough without worrying that I'm going to get bar stock or a chuck tossed through my head.

I just use a liberal application of RapidTap cutting fluid, a slow but steady infeed, and I vary the spindle RPM until it "sounds" right (usually 200-300 RPM). On my machine I can tell from the chatter when things are about to get hairy. Make sure your parting tool is perpendicular to the piece too. The few times I've had it very slightly angled it's started chattering inside the cut and eventually snagged and broke.

 

[CMAG]

Also make sure your cutter is on center or a hair below center, never above center.
easy way to do that is pinch a 6 inch steel ruler (or 030/ .035 feeler gauge) between tool and chucked round bar if the ruler stands strait up and down you are center if the top or ruler leans over bar you are high

 

[ShineOnYouCrazyDiamond]

Great tips - thanks.

I was searching for help and found this video https://www.youtube.com/watch?v=-RZRq0olsxM.

I also worked to check that I was on center and flat with the work. Thing that happened at one point is the vibration caused the compound rest to jiggle and move a few thousandths. Do you think I need to check the gibs for tightness?

 

[CMAG]

most likely the handle on your compound moved in the direction of the backlash and the slide never moved
take up the backlash set dial to zero and watch to see direction dial moves.
also when you take up backlash if possible keep the handle at the bottom the weight of the handle may help keep the wheel from turning, and check to see if you can adjust friction on the hand wheel.
check gibs if you suspect a issue there but be sure you know what your doing.
Intresting vid the animation also shows if running forward why I was told to keep cutters a hair below center

 

[gadget_lover]

I knew that we had discussed this before. It took a bit of searching...

http://www.candlepowerforums.com/vb/showthread.php?353516-Lathe-Parting-Tool-Woes

On a small lathe it is critical to lock down everything that should not move before you part off a piece. The tool post, compound and even the cross-slide can move under the pressures created as the parting tool bites into the work IF the gibs are not tight. I used an indicator on the carriage to measure the VERTICAL movement of the topslide and crossslide and found that it moved a lot more than I expected until the gibs were properly adjusted.


Daniel

 

[ShineOnYouCrazyDiamond]

After I watched some more videos and read through more threads on parting I also realized that I was parting off very far from the chuck (relatively speaking). Just a side affect of not having the ability to push work through the head stock. I guess I'll just have to accept a little more wasted stock and work on slightly smaller pieces at a time.

 

[CMAG]

Sometimes I cut stock long enough for 2 part's, machine one end flip it machine other end then saw in half instead of parting then face cut the saw cut ends to size and finish turning/milling

 

[ShineOnYouCrazyDiamond]

Not a bad idea.

I ordered a 4" chuck so that I can get about 0.875" through the chuck, if not through the head. That'll give me a little more room to move some pieces back and not be working so far out.

Quick question for you guys in terms of order of operations. If I am going to be working on something that I need to face, then turn the sides and also bore a center hole what would be the preferred order of operations? Would it be face, then bore, then turn - or - face, then turn, then bore?

 

[ShineOnYouCrazyDiamond]

I'm also wondering..... How the heck do you guys keep your depth and width measurements straight without a DRO? The mini lathe is 0.04" per turn and it's confusing as hell especially since the control moving the saddle along the ways is not marked at all. You have to rely on the slide and compound for measurements and as soon as you move the saddle a little everything which is zero'd out gets lost.

 

[m4a1usr]

Some really good tips in the above posts. I adhere to almost all the afore mentioned. Learned them the hard way unfortunately but I guess that's how a lot of us learn. The one thing I didn't see mentioned (or I missed it?) is material temperature when working with it. Especially when parting. I have always gotten much better results if I just allow the piece to cool down if I'm doing critical cuts. Like a last finish pass or similar. Since we have no built in cutting lubrication system like the bigger lathes a decent understanding of material elasticity will save a bunch of headaches just when you need to be very careful.

Copper has always been my biggest problem child. I have aluminum and brass down pretty good. And learning to just slow down once the product takes shape cannot be overstated. You've probably already experienced just letting something drop down 20 or 30 degrees cuts a whole lot easier.

 

[gadget_lover]

I don't have a set pattern for turn/face/bore.

In general, I'll face it before starting so I have a reference point for all of my work. My drawings are all referenced as X inches from that end.

The order of turn, then bore is dictated by how close you need the bore to be concentric to the outside of the light. When possible, you want to leave the work in the chuck after turning so that the drilling or boring or threading HAS to be concentric with the outside. A typical 3 jaw scroll chuck will be off by several thousandths when you remount your work for additional operations. If you have a high end chuck or use collets you can remount the light and still be centered the same.

When it comes to depth and width measurements, a pad and pen will be helpful. I upgraded my micro mill and mini lathe to using 20 tpi lead screws (as part of another upgrade) , so each turn is .050. I find that easier to calculate.

A carriage stop is a handy thing to have. That keeps the saddle from moving past a certain point when you are working. I made mine out of a small block of aluminum that clamps to the bed. I use it with the half-nuts so that the saddle can't move left or right when I'm parting.

Daniel

 

[CMAG]

You can use a dial indicator and magnetic base like a dro

 

[CMAG]

you can use a dial indicator with magnetic base as DRO
As Gadget said face first so you can gauge off that surface and your center drill does not walk

 

[DrafterDan]

I use a dial indicator on a mag base as a stop marker. Much nicer on the equipment if I don't happen to disengage the half-nut in time....

But using a dial sure make the calculations easier, at least for me

 

[m4a1usr]

Well another thumbs up for 6061dude! Ordered some 1-1/8th brass stock this past Sunday for long time on hold project and it came in today. You gotta love his priority mail service. He always processes orders in less than 24 hrs too. Now to get busy with making that Surefire 9AN clicky adapter.

 

[CMAG]

I use a dial indicator on a mag base as a stop marker. Much nicer on the equipment if I don't happen to disengage the half-nut in time....

But using a dial sure make the calculations easier, at least for me

+1 stop's are for manual feed only.
drafter what model lathe you have ?, looks like my old MSC branded 12x24 trying to find parts with no luck

 

[DrafterDan]

CMAG, this is actually my fathers' lathe. It is a Chinese unit, Shenwai model SW-350b. It's pretty old and cranky, but accurate enough for flashlight bits. Thankfully we have not had to replace any major components, long may that last.

He and I built a complete metalworking shop so he could work on his British sports cars. It's funny that I'm almost 50, but still rely on dear old dad My only grip is that he uses my nice finishing inserts to hog out brass all the time.....

This was his last major project. Built from scratch - except for the fiberglass body panels. A Lotus 7

 

[Tre_Asay]

I am probably a little late but check any metal supplier, they usually have scrap pieces of aluminum (round and square stock) for cheap.
Price wise will beat using premium alloys until you get the hang of it.
Then again I have not done any real machining so take it with a grain o' salt.

 

[CMAG]

CMAG, this is actually my fathers' lathe. It is a Chinese unit, Shenwai model SW-350b. It's pretty old and cranky, but accurate enough for flashlight bits. Thankfully we have not had to replace any major components, long may that last.

He and I built a complete metalworking shop so he could work on his British sports cars. It's funny that I'm almost 50, but still rely on dear old dad My only grip is that he uses my nice finishing inserts to hog out brass all the time.....

This was his last major project. Built from scratch - except for the fiberglass body panels. A Lotus 7

Nice:thumbsup: ride