Thread: Knurled Screws for Graduated Dials

Originally Posted by Steamwhisperer

Hi Bruce,
so, not only are we as one in imperial, but screwcutting as well
My apprentice master hated runout grooves unless the situation required so insisted on tool withdrawal as the preferred method. It does take some practise but once mastered looks great. Like you I prefer to screwcut rather than use a button die and it is only recently I have started using the angular approach. Normally I would plunge cut until about half the thread depth then use slight top slide movements coupled with gradual depth cuts on the compound until I reached full depth. After a while you get to know when you are close to the finished thread. I love the idea of being able to put any thread I like on any diameter I like.

Phil

Phil
Thanks for your reply.
Sometimes, I will use the angular approach which gives a nice cutting action.
When the thread is small in dia I often use the plunge cut. So no definite method.
I do not get great results with button dies either, & its nice screwcutting in the lathe.
By the way still looking for a shaper, but in the meantime going to therapy classes.
regards
Bruce

Neat job I need to try and do that on my lathe. When I am screw cutting I use an indicator so I know the actual thread depth

Originally Posted by Anorak Bob

I take it that you boys are using high speed steel. Coitus interruptus with carbide is bound to be troublesome. It is all too easy to snap the end off in the work if coordination is not perfect.

Always Bob,
the apprentice master didn't like carbide either. He also wouldn't let me use coolant as he said I could use the practise in tool grinding and re-setting. It's funny, I never thought I would hear the term 'coitus interruptus' in engineering but when you think about it, it is really quite apt. Cruising along doing something thats fun then pulling out at the last minute under great duress...just like screwcutting without a runout groove. Or maybe my mind just wandered over to the darkside.

Phil

Originally Posted by Anorak Bob

I take it that you boys are using high speed steel. Coitus interruptus with carbide is bound to be troublesome. It is all too easy to snap the end off in the work if coordination is not perfect.

BT

Bob
Yes still using HSS
I have 2 pieces of ASSAB HSP Sweden HSS (had for yonks, a long time) with a 55 degree on one end & 60 degree on the other I have them held together by a piece of doublesided sticky tape.
Both toolbits are at the correct centre height to clamp into the lathe toolpost.
Not what one would call an "Engineering Masterpiece" but it works & I reckon these 2 pieces have cut stacks of threads & will outlast me.
Easy to touch up off hand on the grinder. I just grind them to a gauge angle. The 60 degree gauge was a nice old Brown & Sharpe puchased recently from the USA on E bay. Read your details on the carbides for Andre, but I get lost in all of the carbide jungle, however I am sure they are good.
regards
Bruce

Being the complete cheat that I am, I begin by cutting a thread in the lathe, but finish it with a die (if I have it) mounted on the tailstock. That way it will be accurately nice and parallel (not drunkenly tilting off to one side, as could happen by hand threading only), and the finish is better than I can manage on the lathe. It's also easier than doing the whole thread with the tailstock-mounted die only.

Jordan

Originally Posted by Steamwhisperer

Always Bob,
the apprentice master didn't like carbide either. He also wouldn't let me use coolant as he said I could use the practise in tool grinding and re-setting. It's funny, I never thought I would hear the term 'coitus interruptus' in engineering but when you think about it, it is really quite apt. Cruising along doing something thats fun then pulling out at the last minute under great duress...just like screwcutting without a runout groove. Or maybe my mind just wandered over to the darkside.

Phil

It's funny. I "pulled" that post because I thought some may find it inappropriate.

Originally Posted by Abratool

I have 2 pieces of ASSAB HSP Sweden HSS (had for yonks, a long time) with a 55 degree on one end & 60 degree on the other I have them held together by a piece of doublesided sticky tape.

Bruce,
I might try making up a double-ended thread cutting tool like yours before I go down the carbide insert road. They look like 3/8. Is that right?
Chris

Bruce had copied me an email he sent to Chris regarding the variation in screw lengths that might occur between the 9 and the 260. Here are a few photos.

The last photo shows the 1958 9's cross slide screw at top left. For some reason I didn't make one for the compound on that lathe. On the right are the screws from the '69 ARL and the bottom three are the screws Bruce needs to make for his beige No.O mill.

The late 9s and the 260 share the same larger graduated collars.

Hope this helps.

BT

Hey Bruce,

Have you ever been tempted to acquire a quick change toolpost?

Bob

Originally Posted by Anorak Bob

Hey Bruce,

Have you ever been tempted to acquire a quick change toolpost?

Bob

Bob
Been tempted many times, however I find they take up a fair bit of space.
A bit like the Turret Attachment we have communicated about previously.
So I just have the "Lock" toolholders they accept 1/4" square HSS toolbits I have 3 of them which satisfies most jobs.
Also use some 1/2" square HSS with packings adhered to be at the right centre height. The boring bars are similiar with pieces I have milled to the correct height to save searching for packing pieces.
A quick change toolpost would be nice, but the space thing has been the hold back.
regards
Bruce

Originally Posted by jack620

Bruce,
I might try making up a double-ended thread cutting tool like yours before I go down the carbide insert road. They look like 3/8. Is that right?
Chris

Chris
Yes they are 3/8th" square.
regards
Bruce

Originally Posted by Anorak Bob

Bruce had copied me an email he sent to Chris regarding the variation in screw lengths that might occur between the 9 and the 260. Here are a few photos.

The last photo shows the 1958 9's cross slide screw at top left. For some reason I didn't make one for the compound on that lathe. On the right are the screws from the '69 ARL and the bottom three are the screws Bruce needs to make for his beige No.O mill.

The late 9s and the 260 share the same larger graduated collars.

Hope this helps.

BT

Bob
Cant remember if you Loctited the brass end pieces on to the screws?
Bruce

Nup.

Just a push in fit for when the next bloke or the bloke after him wears them out and they need replacing.

Back to the QCTP. With the dough you saved by not buying the 270 shaper you could pick up a nice Rapide or Dickson. If you reckon you need more room at times simply fit your square block or even the lantern post.

im in awe of you blokes that can make stuff on lathes mills ect ect i have a mate who turns up my work for me he has a nice lathe and a cnc at home .the amount of times i have gone around there with a hand drawn picture and me telling him what i want and whats its for and he just makes it lol.

been a mechanic i need special tools made up for one jobs and bits turned up for my race car so i would just like too say i tip my hat to you blokes you blokes make life easy for mugs like me when i need something .
cheers dean