Machined pengun - Dimply

[LeMaudit]

This is costing me a lot of brass

Told you to practice with wood and plastic!

From Wikipedia:

The use of a suitable lubricant is essential with most tapping and reaming operations. Recommended lubricants for some common materials are as follows:

Carbon steel
Petroleum-based or synthetic cutting oil.
Alloy steel
Petroleum-based cutting oil mixed with a small amount (approximately 10%) of kerosene or mineral spirits. This mixture is also suitable for use with stainless steel.
Cast iron
No lubricant. An air blast should be used to clear chips.
Aluminum
Kerosene or mineral spirits mixed with a small amount (15-25%) of petroleum-based cutting oil. WD-40 and 3-In-One Oil are acceptable substitutes in some cases.
Brass
Kerosene or mineral spirits.
Bronze
Kerosene or mineral spirits mixed with a small amount (10-15%) of petroleum-based cutting oil.

Notice that I spelled tapping correctly, not taping! Hint Hint LeMaudit There is a difference in tape and tap!

I don't undeftand you fir! I zaid faping, what'f the problem wif zat?

[jackssmirkingrevenge]

It is about time you are using a lathe!
How many years ago did I tell you to get a damn lathe?

You did, you did... but see, it's happened

Told you to practice with wood and plastic!

How does cutting wood and plastic teach me about brass

The use of a suitable lubricant is essential with most tapping and reaming operations

That is clearly what she said well, it seems unless I can dig some paraffin out of the garage I'm stuck for the weekend :-/

Also, I seem to be generating a lot of brass shavings. Did I say brass shavings? I meant epoxy filler

[LeMaudit]

How does cutting wood and plastic teach me about brass

Brass, little. But proper use of the tools? A lot
And that way you keep your precioussssssss brass.

unless I can dig some paraffin out of the garage

don't you have some paint thinner, to clean brushes?

It is reported as an old trick to use milk for brass and copper. I never tried it.

Did I say brass shavings?

bra shaving?

[jackssmirkingrevenge]

And that way you keep your precioussssssss brass.

My precioussss!!!

Methinks I'll use the two bits I have for practice and try to cut threads on the other side.

don't you have some paint thinner, to clean brushes?

I'm sure there's something somewhere.

It is reported as an old trick to use milk for brass and copper. I never tried it.

I'm not pouring milk on my brand new lathe!

bra shaving?

Yes.

edit: found some white spirit.

[LeMaudit]

One think obvious maybe...

put some grease on the rails so the tailstock can move easily... and push the tailstock while you turn, as you want it to advance at the same time as the thread is cut.

Yes, White Spirit will do.

And yes, practice is good

[jackssmirkingrevenge]

One think obvious maybe...

put some grease on the rails so the tailstock can move easily... and push the tailstock while you turn, as you want it to advance at the same time as the thread is cut.

Tailstock is sliding nicely but no joy with either end of the die. Diameter is 11.70mm

How do you chamfer the end to help things?

[velocity3x]

Jack,
Have you given thought to acquiring a tool grinder to keep your lathe tools sharp?

[LeMaudit]

How do you chamfer the end to help things?

I don't.

I've threaded lots of rods the way you do it, before I bought the die support. No obvious reason it does not work.

[jor2daje]

Did you get a decent quality tap and die set? Even low quality should handle brass but you never know. Also if starting the thread is the only problem make the part a little oversize then part off or cut down the crappy part Of the thread

And are you locking the tailstock or sliding it by hand like lemaudit said? If not it won't thread correctly

Edit looking at your picture I think the piece you are threading is too large in diameter for the die are you sure it's the correct die?

[jackssmirkingrevenge]

Jack,
Have you given thought to acquiring a tool grinder to keep your lathe tools sharp?

It's on my ever expanding shopping list...

Did you get a decent quality tap and die set? Even low quality should handle brass but you never know. Also if starting the thread is the only problem make the part a little oversize then part off or cut down the crappy part Of the thread

After some discussion with LeMaudit, we came to the conclusion that:

a) my tap and die set is the product of defecation

b) 1/2" or so threads is around the limit that can be cut using the method described.

And are you locking the tailstock or sliding it by hand like lemaudit said? If not it won't thread correctly

It's not locked, I was sliding it by hand.

looking at your picture I think the piece you are threading is too large in diameter for the die are you sure it's the correct die?

Yep, 12 x 1.75 - LeMaudit tried to do the same with a 1/2" die and had similar results. Or at least he claimed he did, in order to convince me to buythis and further his commision with Sherline

I did manage something better though, starting it off on the "wrong" end then manually continuing with the tapered end while the part was clamped in a vice, using white spirit as cutting fluid.

Bedtime now but I'll give the proper part another go tomorrow. Any objection to threading before drilling the central hole?

[jor2daje]

Haha least you got som half decent results the thread cutting attachment looks like a great investment it's on my list right after the rotary table. I saw a cool video with a guy who made a quick change gear box for it so you don't have to fiddle with change gears and setup so much, though you may still have to crank the handle

[LeMaudit]

Or at least he claimed he did, in order to convince me to buy this and further his commision with Sherline Wink

I only get the $10000 commission after my 1000th addict. Nada before that number. You see I have still a long way to go

Sherline!! who want a Sherline? Sherline for everyone, brand new... shiny... SHERLIIIIINE...

[ramses]

Milk does work on copper, but I suggest you use it in a well ventilated area. I nearly vomited last time. Then I resorted to rather ridiculous speeds, carbide, and plain water as lubricant.

For future threading, you could lock the tailstock, then use the ram to force the die holder against the workpiece.

[jackssmirkingrevenge]

Sherline!! who want a Sherline? Sherline for everyone, brand new... shiny... SHERLIIIIINE...

You have no idea how amazingly close that representation is to how it looks like in my head

For future threading, you could lock the tailstock, then use the ram to force the die holder against the workpiece.

Tried that, didn't work

Going to give the part another go.

edit: not too happy about the thread, major diameter is 11.1mm and I'm pretty sure I hadn't turned it down that far... hmm. Anyway, part done. ish.

[inonickname]

BTW, on the note of lubricants, if you have enough power and carbide bits sometimes it better to cut no lube. For example I use carbide bits and run them hot on purpose, so the chips are curling off thick and a burnt blue colour, or black. Carbide cuts most efficiently hot (but you want lubricant when you come to do your final cuts).

Might not be an option for you, seen as you don't have the two horses on tap