Here is a list of all the postings Steve Crow has made in our forums. Click on a thread name to jump to the thread.
|Thread: How many Hammers|
That is one handsome hammer!
|Thread: Metric tap and die set|
I've got a M2 to M6 set from Tap and Die Co. Made from HQS ( don't ask - just search the forum).
I use the (split) dies mainly on silver steel and they do a fine job. Nice box too.
|Thread: Thread Size Help|
That's some site. The very first page I looked at, I saw the thread I want! It' s a 3/32 100tpi sewing machine thread!
I'm sure taps for that are easily available.......
Thanks everybody, I had considered inventing my own thread (M2.3 x 0.25 sprang to mind) but I don't have access to a grinder so the thought of making a tap of that size is a little daunting. If I had a bit more time on my hands I would give it a go, especially as the nut will be brass.
Thanks Jason, I like the M2.5 x 0.4 idea as I already have taps and dies. I like to work in metric but I mix and match when it comes to very small stuff to get a wider range of sizes. Hence the use of a 3/32 bearing.
Also there are some great thread charts linked above. Very comprehensive yet Tracy Tools stock threads that don't seem to exist anywhere else!
I'm trying to find a thread (with available taps) with a major diameter of less than 2.4 mm and a minor of 2mm.
It's for a shaft that passes through a 3/32 bearing which needs a nut that clears a 2mm section.
And it would make life much easier if it was 60 degrees as well.
I'm not bothered about the die as I can single point cut it.
I've looked at the usual places. Zeus charts, Tracy Tools and Google but can't find anything.
There must be some fairly fine 3/32 thread out there.
|Thread: Why are insert toolholders so expensive?|
Oh. I hope my mild steel holder is up to the job!
They are on offer at the moment but only as a kit with 4 inserts, none that I need.
I have just made a toolholder for a grooving insert as I didn't want to spend £70 to buy one. Link - Scroll down for pictures.
I know there are some very reasonable prices out there (JB for example), but once you start looking at name and industry stuff, you're nearly at 3 figures.
Most don't seem to have any weird geometry or seem particularly difficult to make.
Am I missing something here? Exotic materials maybe?
I can understand the need for something really rigid with boring bars but general turning tools?
I'm sure I'll be enlightened shortly.
Edited By Steve Crow on 10/09/2019 19:13:09
|Thread: Home Made "Inserts" -Feelin' Groovy.|
A quick update.
I didn't have a huge amount of success with my home made inserts and for an ongoing project I need to cut some consistent size grooves in a variety of materials including EN16T and silver steel. Also I wouldn't mind being able to part pivot steel.
I don't like to spend more time sharpening than turning so I cheated and bought a "Mini-Thin" 0.5mm insert and the torx screw in case it was an odd size (it was).
Once I'd recovered from the cost, I knocked up a toolholder from 3/8" square bar.
I've not tried it out yet but if I'm happy with it I might get the threading insert. Should be good for making screws from pivot wire.
It's got me thinking about making other toolholders now for other types of inserts.
Edited By Steve Crow on 10/09/2019 18:53:12
|Thread: Any one used a digital microscope for micro turning on a lathe|
Bill, I am also blessed (?) with myopia. Anything under 8 inches is pin sharp, everything over that and I'm in varifocal land.
Also my lathe is tiny and most of the real small stuff I do is in collets so I can get right up close.
I mentioned my hobby to my optician who told me he tests the people from an assay office and other "close" trades and makes special close-up specs for them.
I got a pair made and they are perfect for the 6 to 18 inch range.
Also, I never do any naked eye work, no matter how benign, without safety specs. Because I've worn specs for most of my life, I forget they are "not there" and had a couple of near misses with needle files, for example. I got a pair of those posh ones you see on the Arc-Euro ads and they a very light and comfortable and very clear too compared to those scratchy old ones of yore.
How do dentists know what they need? Maybe check an amateur dentists forum!
|Thread: Drawbar Thread|
Thanks Jason, I was hoping someone would say that! M6 it is then.
I suppose the difference is that with the WW, you are closing a split tapered collet, hence the finer (40 tpi) pitch.
I need to make a drawbar for some homemade MT1 arbours for use on a Sherline.
Now, looking a 8mm WW drawbars, I'm assuming that a fine thread would be advantageus.
Is this correct or could I get away with a metric coarse thread? Just to save me buying fine taps and die.
|Thread: Any one used a digital microscope for micro turning on a lathe|
I find the Optivisor headset excellent for when I'm turning very small parts.
You choose the lens by focal distance rather than magnification so you can select one that is comfortable to work with. This helps prevent any aches and pains from being scrunched up. Very comfortable on the head too.
Good stereo vision, decent width and depth of field and you can "look under them" for a naked-eye view without lifting the visor.
If you get an opportunity to try a pair, please do. They are the only form of magnification I've ever really got along with.
|Thread: Pivot Steel - Machinability|
You are very warm indeed, especially if I can thread the stuff! Also parts for an engine to power it. And for a planned experimental Brocot escapement.
Maybe also small tools like special punch/anvil things for my staking set and, now I know I can turn it so easily, "toolmakers "reamers for use on brass.
All sub 3mm stuff.
I'd planned to make a lot of these out of silver steel but with all the heat treating and (my pet hate) descaling and cleaning, hopefully pivot steel (regardless of it's demise in quality) will save me a lot of time and effort.
Thank you Michael, I do see old stock occasionally on Ebay.
Mind you, I'm not making balance staffs from it!
What is pivot steel?
I've always assumed it was a high carbon steel like silver steel but at a spring temper.
I've not been able to find out much on the net. There is a standard, EN 4454, but beyond that, nothing.
Can anyone enlighten me?
Edited By Steve Crow on 01/09/2019 17:10:10
Jason, the small parts in question are all quite slender and sub 3mm diameter and are not suitable for EN1A and the like.
At the moment , I'm making them from silver steel and heat treating them.
To be able to eliminate all the messing about and the risk of distortion in very appealing.
In addition, when turning long slender sections, that pivot steel does not want to flex. It surprised me how long an unsupported piece I could get away with.
It takes a nice polish too.
I recently used carbide inserts to turn pivot steel with very satisfying results. Link
This has got me thinking about using it more for small parts.
Surely it should single-point thread easily with an insert?
How about milling and drilling with solid carbide cutters? These can be picked up at less than the price of HSS endmills through ebay sources.
If anybody has used these methods or has other observations regarding using carbide, please let me know.
Also, has anyone any comments on the allegedly variable quality of pivot steel "from certain countries" as one poster has it? Mine's from Cousins.
Edit: The link above goes to the top of the page. Scroll down for my post and pictures.
Edited By Steve Crow on 01/09/2019 14:14:46
|Thread: Shape of insert on Sherline Lathe|
Thank you Michael. This was primarily an experiment and demo for myself also.
But, the dimensions are not random. I have a potential use for each diameter starting from the smallest. As one is damaged, I face it off and use the next one for a different purpose. Waste not, want not.
This might interest you Chris.
For the first time, I had a go at turning blue pivot steel with an insert tool on my Sherline rather than with a hand graver on my watchmakers lathe.
I used a DCMT (55 degree) insert with a 0.4 radius. The pivot steel was around 2.6mm OD and I turned it with about 15mm hanging out of the collet.
The diameters are 0.45, 1.2, 2.0 and 2.4 mm. The 3 smaller sections are 2mm long.
I experimented with different depths of cuts. It comes off beautifully with a 0.25 cut (0.5 mm total). Also finishing cuts of 0.01 mm are fine. Nice finish too.
It might not be a suitable method for completing a balance staff but you might be able to use it for roughing one out before finishing between centres.
After this, I intend to use pivot steel a lot more rather than silver steel. Amazing things those inserts! I've got to say, I'm a total convert.
Edited By Steve Crow on 30/08/2019 16:01:45
Edited By Steve Crow on 30/08/2019 16:02:28
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