PDA

View Full Version : 10EE Screwcutting gearbox



John Stevenson
04-01-2009, 01:40 PM
Anyone got a 10EE that they can look at the box for me ?
I have a CVA which is the English copy and according to the screwcutting chart it can cut 19 tpi straight out the box.

My box goes from 18 to 20

Rang Tim Leech up and his two CVA's have 19 on the box ?

So there are two gearboxes but only one chart in the UK

So if someone has a 10EE WITHOUT 19 in the box have they got a chart for the extra pitches ?

.

kvom
04-01-2009, 02:17 PM
My round dial doesn't have 19 tpi. Here is a post on PM from Peterh:


The basic Round Dial box gives the following pitches:

6, 6-1/2, 6-3/4, 7, 7-1/2, 8, 9, 10, 11 and 11-1/2 tpi A'

12, 13, 13-1/2, 14, 15, 16, 18, 20, 22 and 23 tpi B'

24, 26, 27, 28, 30, 32, 36, 40, 44 and 46 tpi C'

This is modified by the "end gears" as follows:

With the 48 teeth end gear on the reverse shaft and the 24 teeth end gear on the box shaft:

3, 3-1/4, 3-3/8, 3-1/2, 3-3/4, 4, 4-1/2, 5, 5-1/2 and 5-3/4 tpi A

6, 6-1/2, 6-3/4, 7, 7-1/2, 8, 9, 10, 11 and 11-1/2 tpi B

(12, 13, 13-1/2, 14, 15, 16, 18, 20, 22 and 23 tpi C) Not used

With the 24 teeth end gear on the reverse shaft and the 48 teeth end gear on the box shaft:

12, 13, 13-1/2, 14, 15, 16, 18, 20, 22 and 23 tpi A

24, 26, 27, 28, 30, 32, 36, 40, 44 and 46 tpi B

48, 52, 54, 56, 60, 64, 72, 80, 88 and 92 tpi C

lazlo
04-01-2009, 02:37 PM
The square dial has a bunch more feeds, but I'm looking at the nameplate for the Inch/Metric and it doesn't have 19 TPI either: it goes 18 to 20.

I'm guessing the CVA is a copy of the round-dial 10EE, right?

Timleech
04-01-2009, 04:02 PM
The square dial has a bunch more feeds, but I'm looking at the nameplate for the Inch/Metric and it doesn't have 19 TPI either: it goes 18 to 20.

I'm guessing the CVA is a copy of the round-dial 10EE, right?

That's how they started, but were obviously developed/adapted for the UK market. It seems that 19 tpi doesn't exist in US standard threads, but it does in UK threads, notably BSP.

Mine are later lathes than John's, they were built by another company after CVA had gone out of business though the 'version' was first made by CVA/Kearney & Trecker.

Tim

quasi
04-01-2009, 07:29 PM
My Rivett 10-20f has 19 tpi in its gearbox, if that makes you feel any better.http://bbs.homeshopmachinist.net/images/icons/icon7.gif

wierdscience
04-01-2009, 10:21 PM
Got one at work I will check,it's not running so I haven't looked at it in awhile.

John Stevenson
04-02-2009, 03:55 AM
What's the term RTFM ? :rolleyes:
So looking thru the book last night on the machines same as Tims and it gave an example on how to cut odd pitches and they used 19 as an example [ ?? that machine can cut 19 ? ]

However The CVA and I suppose the 10EE has a secondary set of gears for metric, BA, module etc which are all 32 DP it make them fit in the space, I have this set but it turns out that there are others in the standard set at 16DP which I don't have.

The big TOS can do 19 but it's a pain to make a small union nut on.

looks like I've got to learn how to do internal threads on the little CNC lathe. :mad:

So far with looking / book reading/ wasting my time typing etc I'm about 2 hours into making just this one small union nut which I'm not going to get paid for .

It's off the toilet in a yankee motorhome for Malc the scrappie, but then again that's what friends are for.

.

Timleech
04-02-2009, 04:39 AM
What's the term RTFM ? :rolleyes:
So looking thru the book last night on the machines same as Tims and it gave an example on how to cut odd pitches and they used 19 as an example [ ?? that machine can cut 19 ? ]

However The CVA and I suppose the 10EE has a secondary set of gears for metric, BA, module etc which are all 32 DP it make them fit in the space, I have this set but it turns out that there are others in the standard set at 16DP which I don't have.

The big TOS can do 19 but it's a pain to make a small union nut on.

looks like I've got to learn how to do internal threads on the little CNC lathe. :mad:

So far with looking / book reading/ wasting my time typing etc I'm about 2 hours into making just this one small union nut which I'm not going to get paid for .

It's off the toilet in a yankee motorhome for Malc the scrappie, but then again that's what friends are for.

.

John, I think you ought to have been up half the night making the missing gears :D :D

That's not the first case I've come across of a machine being updated but the manual only halfway updated to match the machine.

I had a quick look through my odd taps, just in case, nearest is 1 1/4" x 20 so no help there.

Tim

Mark McGrath
04-02-2009, 05:02 AM
Just went and checked my CVA.I have 19 tpi threading.The machine is a 1A, Ser 111, Serial number 1331. Which I think is mid sixties.
There were two versions of these lathes,a toolroom version and a workshop version,possibly the workshop version has less threading pitches available.

Mark.

Edit:
I have three CVA manuals.One without a cover,so don`t know the exact model.One for a 1A and one for a 1A Ser111.
One with no cover lists 50 pitches 3-92tpi not inc 19
One for 1A lists 50 pitches 3-92tpi not inc 19
One for 1A Ser 111 (my machine) lists 50 pitches 3-88tpi and states at the side it includes 19tpi
Going by the inspection chart for my machine it is a 1961 model.

John Stevenson
04-02-2009, 07:15 AM
Thanks guys, now sorted.
Did a dummy with an old brass bush on the CNC as it wasn't obvious how internal threading worked.
Wasn't too happy about swapping root dia for OD but it worked OK

It looked to be 1/2" gas size but with 19tpi instead of 11.

Tim, don't think I'll bother with any gears as this is the first time I have been caught out and now got the CNC.
If it's too big for the CNC then I'd favour getting gears for the small TOS as it has nicer clutches than the CVA.


.

Mark McGrath
04-02-2009, 08:03 AM
"It looked to be 1/2" gas size but with 19tpi instead of 11.

Is 1/2" gas not 14tpi down there then?

John Stevenson
04-02-2009, 10:23 AM
No 14 tpi in Scotland and as soon as you get to Scotch Corner you get your passport stamped, change your money and 1/2" gas changes to 11 tpi. :D

not having good day, bloody customers are being a pain again - as always.

.

John Stevenson
04-03-2009, 11:34 AM
So I'm working on the small TOS today doing some decent sized pins, 50mm diameter down to 35mm about 150mm / 6" long

As I was working I was thinking about this 19 tpi problem if it came up again, my mind works like that, and decided this TOS was the better machine to do as it has better clutches and a neutral in the box, something the CVA doesn't and it's a lot harder to turn that one by hand or the chuck key [ handy for very short threads ]

Dug the book out and the formula is there to work odd threads out but I can't do that in my head so tonight's job, get a list of gears and sit down with Excel. Print a sheet up and fit it inside the end cover, no room with the rest of the charts on the front.

Hogging big cuts off and the work wants to move back in the chuck so fit the work stop. Simple short taper that fits the headstock, tapped to take a length of all thread that can be adjusted for length and a large washer and nut on the arse end,.

Set length, open end cover to fit nut and washer and look what I found - :rolleyes:

http://www.stevenson-engineers.co.uk/files/gaschart.jpg

Was it South Bend who had a book called "Know your lathe" ? Duh :p

.

small.planes
04-03-2009, 03:42 PM
11 1/2? I can see that one coming up all the time? (what's it for?)

Dave

Mark McGrath
04-03-2009, 04:09 PM
11 1/2? I can see that one coming up all the time? (what's it for?)

Dave

It does come up quite a lot if you are making pipe fittings.It`s common in NPT threads.Much like 11 tpi is common on BSP here.
Probably also used a lot in the Long Eaton area for certain metric pitches.(saves changing gear on the CVA) :-)