Cheap eBay threading tools

[Maker]

This kind of thing, anyone got any experience with them?

I need to cut some fine internal threads, too fine to use a readily available tap (10 and 18mm at 0.7mm pitch off the top of my head) and too fiddly for me to grind my own HSS bit.

Are these things all over eBay worth getting? I only need one of each size in aluminium and in brass so my other option would be make a couple of taps - I am leaning towards this idea as I've never cut an internal thread on a lathe before and I don't want to bugger it up.

 

[optima21]

I've only bought small boring bar inserts (not for threading), but they dont have enough clearance, so you'll have to mount then with huge amounts of rake or way above centre height.

 

[mike os]

They are quite adequate. ..

 

[grim_d]

All my carbide insert holders (apart from parting tool) are the cheapest Chinese available on eBay.

Every single one of them is spot on.

Don't have an internal threading one yet but I definitely want one.

 

[knighty]

for ali and brass you could make some taps out of bolts?

 

[Kram]

Ive got a chinese internal threading holder and branded inserts - not chinese. I think I got the smallest one I could find. Inserts fit perfectly. had it couple years have not tried to use it yet. Threading is something I want to do but requires a bit more time for setup and learning than I usually have..

 

[Maker]

for ali and brass you could make some taps out of bolts?

I could if I had some M18x0.75 bolts.

I did start to make a tap to do it and then filed the relief on the wrong side of the flutes. Haven't gotten around to making a new one yet as cutting metric threads on an imperial lathe (Can't disengage the leadscrew) is very tedious.

 

[zx9]

They are ok , same as a boaring bar, don't have any more bar hanging out of the holder than you absolutly need to but aluminium and brass they will be fine. QUOTE="Maker, post: 1200798, member: 22649"]I've never cut an internal thread on a lathe before and I don't want to ****** it up.[/QUOTE]
Have a couple of practice pieces first but it is not difficult to get the hang of, if I could cut a successful internal thread using the Drummond before I even attempted an external thread I am sure a man with your lathe experience will have no problems.

 

[MattF]

I've only bought small boring bar inserts (not for threading), but they dont have enough clearance, so you'll have to mount then with huge amounts of rake or way above centre height.

Same as Optima', I've got an insert boring bar, but they're a pain for anything small. Personally, I'd be going with a thin rod, drilled through at 90% or whatever angle you fancy, for a thin HSS rod to be inserted. Drilled and tapped through the end for a securing grub screw to secure the HSS. Insert holders need a stupid amount of clearance in comparison to that method. You're obviously more prone to flex on the tool,, but clearance wise you only need to allow for the diameter of the rod + however much of the HSS you have protruding from it.

I've got some knocking about somewhere. I'll take a photo when I find one, to illustrate. So is it not a standard thread you're trying to cut? Taps are simpler if it is.

 

[zx9]

Same as Optima', I've got an insert boring bar, but they're a pain for anything small. Personally, I'd be going with a thin rod, drilled through at 90% or whatever angle you fancy, for a thin HSS rod to be inserted. Drilled and tapped through the end for a securing grub screw to secure the HSS. Insert holders need a stupid amount of clearance in comparison to that method. You're obviously more prone to flex on the tool,, but clearance wise you only need to allow for the diameter of the rod + however much of the HSS you have protruding from it.

I've got some knocking about somewhere. I'll take a photo when I find one, to illustrate. So is it not a standard thread you're trying to cut? Taps are simpler if it is.

It is an 18mm internal thread he is making so a 8mm or 10mm bar will have plenty of clearance.

 

[MattF]

It is an 18mm internal thread he is making so a 8mm or 10mm bar will have plenty of clearance.

He's doing a 10mm too.

 

[roofman]

All my carbide insert holders (apart from parting tool) are the cheapest Chinese available on eBay.

Every single one of them is spot on.

Don't have an internal threading one yet but I definitely want one.

View attachment 149884

I would like to have the same type of toolpost and holder as you have there matey for my Harrison..do you have any links please? oh and do you have enough holders

 

[zx9]

He's doing a 10mm too.

I missed that bit, I suspect it will be 10x.75 https://www.tracytools.com/taps-and-dies/metric-taps-dies/10-x-75-metric not .7

 

[mike os]

Tbh for small diameter a tap is a better and far easier option

 

[grim_d]

I would like to have the same type of toolpost and holder as you have there matey for my Harrison..do you have any links please? oh and do you have enough holders

Create multifix. www.createtool.com

It's a Chinese knock-off of the Swiss multifix but they are excellent quality, cost more than the Aloris clones but I'm really happy with it.

Go direct to create as they are much cheaper even with shipping and customs than any UK supplier.

And no, I don't...I still find myself swapping tools around. Got all my insert tooling housed but find myself trying different stuff with hss more now so run out of space.

 

[Maker]

Same as Optima', I've got an insert boring bar, but they're a pain for anything small. Personally, I'd be going with a thin rod, drilled through at 90% or whatever angle you fancy, for a thin HSS rod to be inserted. Drilled and tapped through the end for a securing grub screw to secure the HSS. Insert holders need a stupid amount of clearance in comparison to that method. You're obviously more prone to flex on the tool,, but clearance wise you only need to allow for the diameter of the rod + however much of the HSS you have protruding from it.

I've got some knocking about somewhere. I'll take a photo when I find one, to illustrate. So is it not a standard thread you're trying to cut? Taps are simpler if it is.

Something like this?

The point in the side is a snapped 1/4" centre drill, I'll try it on a bit of scrap ali in a minute.

I missed that bit, I suspect it will be 10x.75 https://www.tracytools.com/taps-and-dies/metric-taps-dies/10-x-75-metric not .7

I see they have the 18mm tap I'd need too, it is tempting just to get that and be done with it. Out of stock though.

 

[MattF]

Yup. I took a photo or two of one of mine, and only just realised I haven't posted them.

 

[Maker]

Worked perfectly.


It's for the boss that knob is attached to.

Next job is to bore and thread a hole in the side to accept another shaft (Represented by a (Too big) stainless tube), ideally at about 30 degrees from perpendicular, haven't figured out how to do that yet.

The steel shaft on the right will be attached to the other end of the angled tube so it's parallel to the bore in the brass bit. The brass bit fits onto an identical shaft with the locking knob on the reduced portion, a spring loaded pin in the groove on the opposite side to the knob (Screwed into the 10mm hole) and there's another knob to make that screws into the top of the shaft (Which also needs boring out and rethreading to 18x1mm).