25point4TPI

This topic has 42 replies, 11 voices, and was last updated 16 October 2015 at 18:00 by Ady1.

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7 September 2015 at 15:19 #7790
Ady1
Participant
@ady1
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7 September 2015 at 15:19 #203422
Ady1
Participant
@ady1
I've been goofing around with a c (c++?) package and tried to find how many perms under 100 teeth could hit 25.4 tpi

accuracy is 6 decimal places (float format)

Might be handy for someone, there's more than you'd think

The outputs are headstock->banjo->banjo->leadscrew

So the top one is:

headstock 23 then 59/50(in/out) 59/62(in/out) leadscrew 82

Found a match 25.400000 n[23.000000] n[59.000000] n[50.000000] n[59.000000] n[62.000000] n[82.000000]
Found a match 25.400000 n[23.000000] n[73.000000] n[70.000000] n[97.000000] n[89.000000] n[83.000000]
Found a match 25.400000 n[23.000000] n[73.000000] n[83.000000] n[97.000000] n[89.000000] n[70.000000]
Found a match 25.400000 n[23.000000] n[97.000000] n[83.000000] n[73.000000] n[89.000000] n[70.000000]
Found a match 25.400000 n[23.000000] n[73.000000] n[89.000000] n[97.000000] n[70.000000] n[83.000000]
Found a match 25.400000 n[23.000000] n[73.000000] n[89.000000] n[97.000000] n[83.000000] n[70.000000]
Found a match 25.400000 n[23.000000] n[97.000000] n[89.000000] n[73.000000] n[70.000000] n[83.000000]
Found a match 25.400000 n[23.000000] n[97.000000] n[89.000000] n[73.000000] n[83.000000] n[70.000000]
Found a match 25.400000 n[27.000000] n[59.000000] n[74.000000] n[89.000000] n[77.000000] n[79.000000]
Found a match 25.400000 n[27.000000] n[59.000000] n[77.000000] n[89.000000] n[74.000000] n[79.000000]
Found a match 25.400000 n[27.000000] n[59.000000] n[77.000000] n[89.000000] n[79.000000] n[74.000000]
Found a match 25.400000 n[27.000000] n[89.000000] n[77.000000] n[59.000000] n[74.000000] n[79.000000]
Found a match 25.400000 n[41.000000] n[51.000000] n[52.000000] n[67.000000] n[94.000000] n[91.000000]
Found a match 25.400000 n[41.000000] n[67.000000] n[91.000000] n[51.000000] n[94.000000] n[52.000000]
Found a match 25.400000 n[41.000000] n[67.000000] n[94.000000] n[51.000000] n[91.000000] n[52.000000]
Found a match 25.400000 n[49.000000] n[61.000000] n[69.000000] n[67.000000] n[95.000000] n[97.000000]
Found a match 25.400000 n[49.000000] n[61.000000] n[69.000000] n[67.000000] n[97.000000] n[95.000000]
Found a match 25.400000 n[49.000000] n[61.000000] n[95.000000] n[67.000000] n[69.000000] n[97.000000]
Found a match 25.400000 n[49.000000] n[61.000000] n[95.000000] n[67.000000] n[97.000000] n[69.000000]
Found a match 25.400000 n[49.000000] n[67.000000] n[95.000000] n[61.000000] n[97.000000] n[69.000000]
Found a match 25.400000 n[49.000000] n[61.000000] n[97.000000] n[67.000000] n[69.000000] n[95.000000]
Found a match 25.400000 n[49.000000] n[61.000000] n[97.000000] n[67.000000] n[95.000000] n[69.000000]
Found a match 25.400000 n[49.000000] n[67.000000] n[97.000000] n[61.000000] n[69.000000] n[95.000000]
Found a match 25.400000 n[49.000000] n[67.000000] n[97.000000] n[61.000000] n[95.000000] n[69.000000]
Found a match 25.400000 n[51.000000] n[41.000000] n[52.000000] n[67.000000] n[94.000000] n[91.000000]
Found a match 25.400000 n[51.000000] n[67.000000] n[52.000000] n[41.000000] n[94.000000] n[91.000000]
Found a match 25.400000 n[59.000000] n[23.000000] n[50.000000] n[59.000000] n[62.000000] n[82.000000]
Found a match 25.400000 n[59.000000] n[27.000000] n[74.000000] n[89.000000] n[77.000000] n[79.000000]
Found a match 25.400000 n[59.000000] n[27.000000] n[77.000000] n[89.000000] n[74.000000] n[79.000000]
Found a match 25.400000 n[59.000000] n[27.000000] n[77.000000] n[89.000000] n[79.000000] n[74.000000]
7 September 2015 at 15:19 #203423
Ady1
Participant
@ady1
Found a match 25.400000 n[59.000000] n[89.000000] n[77.000000] n[27.000000] n[74.000000] n[79.000000]
Found a match 25.400000 n[59.000000] n[89.000000] n[77.000000] n[27.000000] n[79.000000] n[74.000000]
Found a match 25.400000 n[59.000000] n[59.000000] n[82.000000] n[23.000000] n[50.000000] n[62.000000]
Found a match 25.400000 n[61.000000] n[49.000000] n[69.000000] n[67.000000] n[95.000000] n[97.000000]
Found a match 25.400000 n[61.000000] n[49.000000] n[69.000000] n[67.000000] n[97.000000] n[95.000000]
Found a match 25.400000 n[61.000000] n[67.000000] n[69.000000] n[49.000000] n[95.000000] n[97.000000]
Found a match 25.400000 n[61.000000] n[67.000000] n[69.000000] n[49.000000] n[97.000000] n[95.000000]
Found a match 25.400000 n[61.000000] n[49.000000] n[95.000000] n[67.000000] n[69.000000] n[97.000000]
Found a match 25.400000 n[61.000000] n[49.000000] n[95.000000] n[67.000000] n[97.000000] n[69.000000]
Found a match 25.400000 n[61.000000] n[67.000000] n[95.000000] n[49.000000] n[97.000000] n[69.000000]
Found a match 25.400000 n[61.000000] n[49.000000] n[97.000000] n[67.000000] n[69.000000] n[95.000000]
Found a match 25.400000 n[61.000000] n[49.000000] n[97.000000] n[67.000000] n[95.000000] n[69.000000]
Found a match 25.400000 n[61.000000] n[67.000000] n[97.000000] n[49.000000] n[95.000000] n[69.000000]
Found a match 25.400000 n[67.000000] n[51.000000] n[52.000000] n[41.000000] n[94.000000] n[91.000000]
Found a match 25.400000 n[67.000000] n[61.000000] n[69.000000] n[49.000000] n[95.000000] n[97.000000]
Found a match 25.400000 n[67.000000] n[61.000000] n[69.000000] n[49.000000] n[97.000000] n[95.000000]
Found a match 25.400000 n[67.000000] n[41.000000] n[91.000000] n[51.000000] n[94.000000] n[52.000000]
Found a match 25.400000 n[67.000000] n[41.000000] n[94.000000] n[51.000000] n[91.000000] n[52.000000]
Found a match 25.400000 n[67.000000] n[49.000000] n[95.000000] n[61.000000] n[97.000000] n[69.000000]
Found a match 25.400000 n[67.000000] n[61.000000] n[95.000000] n[49.000000] n[97.000000] n[69.000000]
Found a match 25.400000 n[67.000000] n[49.000000] n[97.000000] n[61.000000] n[69.000000] n[95.000000]
Found a match 25.400000 n[67.000000] n[49.000000] n[97.000000] n[61.000000] n[95.000000] n[69.000000]
Found a match 25.400000 n[67.000000] n[61.000000] n[97.000000] n[49.000000] n[95.000000] n[69.000000]
Found a match 25.400000 n[73.000000] n[23.000000] n[70.000000] n[97.000000] n[89.000000] n[83.000000]
Found a match 25.400000 n[73.000000] n[97.000000] n[70.000000] n[23.000000] n[89.000000] n[83.000000]
Found a match 25.400000 n[73.000000] n[23.000000] n[83.000000] n[97.000000] n[89.000000] n[70.000000]
Found a match 25.400000 n[73.000000] n[97.000000] n[83.000000] n[23.000000] n[89.000000] n[70.000000]
Found a match 25.400000 n[73.000000] n[23.000000] n[89.000000] n[97.000000] n[70.000000] n[83.000000]
Found a match 25.400000 n[73.000000] n[23.000000] n[89.000000] n[97.000000] n[83.000000] n[70.000000]
Found a match 25.400000 n[73.000000] n[97.000000] n[89.000000] n[23.000000] n[70.000000] n[83.000000]
Found a match 25.400000 n[73.000000] n[97.000000] n[89.000000] n[23.000000] n[83.000000] n[70.000000]
Found a match 25.400000 n[89.000000] n[27.000000] n[77.000000] n[59.000000] n[74.000000] n[79.000000]
Found a match 25.400000 n[89.000000] n[59.000000] n[77.000000] n[27.000000] n[74.000000] n[79.000000]
Found a match 25.400000 n[89.000000] n[59.000000] n[77.000000] n[27.000000] n[79.000000] n[74.000000]
Found a match 25.400000 n[97.000000] n[73.000000] n[70.000000] n[23.000000] n[89.000000] n[83.000000]
Found a match 25.400000 n[97.000000] n[23.000000] n[83.000000] n[73.000000] n[89.000000] n[70.000000]
Found a match 25.400000 n[97.000000] n[73.000000] n[83.000000] n[23.000000] n[89.000000] n[70.000000]
Found a match 25.400000 n[97.000000] n[23.000000] n[89.000000] n[73.000000] n[70.000000] n[83.000000]
Found a match 25.400000 n[97.000000] n[23.000000] n[89.000000] n[73.000000] n[83.000000] n[70.000000]
Found a match 25.400000 n[97.000000] n[73.000000] n[89.000000] n[23.000000] n[70.000000] n[83.000000]
Found a match 25.400000 n[97.000000] n[73.000000] n[89.000000] n[23.000000] n[83.000000] n[70.000000]

Not figured out which is the "best/easiest" one to set up yet though
7 September 2015 at 15:45 #203425
Neil Wyatt
Moderator
@neilwyatt
Too much information

But the missing piece is – what pitch leadscrew? Presumably a metric one?

Neil
7 September 2015 at 19:00 #203454
frank brown
Participant
@frankbrown22225
Just looked at your output. I noticed :-

I've been goofing around with a c (c++?) package and tried to find how many perms under 100 teeth could hit 25.4 tpi

accuracy is 6 decimal places (float format)

Might be handy for someone, there's more than you'd think

The outputs are headstock->banjo->banjo->leadscrew

So the top one is:

headstock 23 then 59/50(in/out) 59/62(in/out) leadscrew 82

Found a match 25.400000 n[23.000000] n[59.000000] n[50.000000] n[59.000000] n[62.000000] n[82.000000]
Found a match 25.400000 n[23.000000] n[73.000000] n[70.000000] n[97.000000] n[89.000000] n[83.000000]
Found a match 25.400000 n[23.000000] n[73.000000] n[83.000000] n[97.000000] n[89.000000] n[70.000000]
Found a match 25.400000 n[23.000000] n[97.000000] n[83.000000] n[73.000000] n[89.000000] n[70.000000]
Found a match 25.400000 n[23.000000] n[73.000000] n[89.000000] n[97.000000] n[70.000000] n[83.000000]
Found a match 25.400000 n[23.000000] n[73.000000] n[89.000000] n[97.000000] n[83.000000] n[70.000000]

Notice the last two outputs, identical except for last two terms, 70, 83 then 83, 70 . (.8433, 1.15871). I can''t get head around if the final ratio of 70:83 gives 25..4 TPI, how does 83 :70 also give 25.4 TPI .

Program would be clearer if "000000" was replaced by "" and more useful if the accuracy was reduced to, say .001.

Frank

Edited By JasonB on 07/09/2015 19:16:31
7 September 2015 at 19:23 #203458
JasonB
Moderator
@jasonb
There are several other pairs of "results" with the same issue, last two on the first post for instance./

Also some have the same issue with teh first two gears eg

59-23, 50-59, 62-82 can't be the same as

23-59, 50-59, 62-82 can it?

Edited By JasonB on 07/09/2015 19:27:21
7 September 2015 at 22:01 #203496
John Stevenson 1
Participant
@johnstevenson1
Something seriously wrong with the program to get these results.

I have taken the first 12 entries and run them thru a spreadsheet. Don't know what pitch screw was going to be used so just done the driver over driven times driver over driven, times driver over driven.

Even if this is wrong I should get the same answer for each line but I don't.
8 September 2015 at 01:27 #203507
Ady1
Participant
@ady1
But the missing piece is – what pitch leadscrew? Presumably a metric one?

tsk tsk tsk TPI is 8, sorry 'bout that

Found a match 25.400000 n[23.000000] n[73.000000] n[89.000000] n[97.000000] n[70.000000] n[83.000000]
Found a match 25.400000 n[23.000000] n[73.000000] n[89.000000] n[97.000000] n[83.000000] n[70.000000]

First one:

(73/89)*23=18.8651etc

(97/70)*18.8651=26.1417etc

83/26.1417etc=3.17499

3.17499*8tpi=25.3999

Second one:

(73/89)*23=18.8651etc

(97/83)*18.8651=22.0472

70/22.0472=3.17499

3.17499*8tpi=25.3999

duh

I got my outputs and my inputs printout muddled up, so it's in the correct order for calculating, but the compound gears need to be swapped round for constructing on the banjo

*sigh*

So the top one is:

headstock 23 then 50/59(in/out) 62/59(in/out) leadscrew 82

Edited By Ady1 on 08/09/2015 01:46:24
8 September 2015 at 02:04 #203508
Ady1
Participant
@ady1
Also some have the same issue with teh first two gears eg

59-23, 50-59, 62-82 can't be the same as

23-59, 50-59, 62-82 can it?

———————————–

59 23-50 59-62 82

23 59-50 59-62 82

first:

(23/50)*59=27.14

(59/62)*27.14=25.82677

82/25.82677=3.17499

3.17499*8tpi=25.3999tpi

second:

(59/50)*23=27.14

(59/62)*27.14=25.82677

82/25.82677=3.17499

3.17499*8=25.3999tpi

It all seems ok to me, (only playing about though)

Without splitting the program up it takes about 10 hours and does around 265 billion permutations

Floats seem to be really slow, I can get around 5 trillion integer checks done in an hour on a bog standard desktop .

(Tried it with basic but I was going to grow old before it finished)

Edited By Ady1 on 08/09/2015 02:30:50
8 September 2015 at 09:02 #203524
Bazyle
Participant
@bazyle
Trouble is if you are going to the trouble of making non standard change wheels like 23 and 59 you might as well do a 127 and have done with it.

I remember doing a program for the BBC computer (2 MHz clock) and waiting until 3 am for it to beep me awake at 3 am. Now the biggest wait is for the bloated operating system to load.
8 September 2015 at 10:23 #203540
Ady1
Participant
@ady1
Trouble is if you are going to the trouble of making non standard change wheels like 23 and 59 you might as well do a 127 and have done with it.

A 127 is gigantic and a real pain to make, ideally, nothing over 75 would be best for a hobby lathe

I can feel another c project coming on…..

23 is easy, I already have a 46. 59 however would need a banjo permutation.

I wonder if…we could go backwards from the leadscrew to cut awkward gears like 59 at the headstock end

Edited By Ady1 on 08/09/2015 10:44:41
8 September 2015 at 11:18 #203549
Michael Gilligan
Participant
@michaelgilligan61133
Posted by Ady1 on 08/09/2015 10:23:45:

A 127 is gigantic and a real pain to make, ideally, nothing over 75 would be best for a hobby lathe

.

Ady,

Martin Cleeve used a clever work-around … His 127 and its driver were 'reduced pitch'

… See here

I am very tempted to try the same idea, but using a Timing Belt for that final reduction.

MichaelG.

Edited By Michael Gilligan on 08/09/2015 11:33:33
8 September 2015 at 11:33 #203552
Ady1
Participant
@ady1
I'm now looking at a "decision making process"

I have 20 25 30 33 35 40 (teeth) and so on…. as my available gears…

I want to make a 59 tooth gear

What new gears can I make with my available gears…. which can be combined with my original gearset to make a 59 tooth gearwheel kinda thing

i.e. "What's the easiest available route for my equipment"

I've only been using this compiler (the 9MB one) for a couple of weeks, it works great in XP, very stable

(All my previous attempts at c were crippleware nightmares)

Edited By Ady1 on 08/09/2015 11:37:49
8 September 2015 at 13:28 #203567
Bazyle
Participant
@bazyle
As I can't load software on my company computer I am restricted to VB in Excel. 'Spose I should buy myself a new box but that's the cost of lots of more tools.

Ady I thought you had an old Drummond so would use a 100 for slow feed. A 127 would enable even slower feed.
8 September 2015 at 15:06 #203575
Ajohnw
Participant
@ajohnw51620
There are 2 programs on lathes co uk that will do this quickly and efficiently. One for lathes with a gearbox and one for those without.

http://www.lathes.co.uk/latheparts/page14.html

They did go missing for a while but should be back now as people found copies for him – so ask if not there.

John

–
8 September 2015 at 16:12 #203582
Neil Wyatt
Moderator
@neilwyatt
If you want to cut gears to a reasonable standard the most useful sizes of change wheel are 60,61,63,64,65,66.

If you can get one of those in the train there will always be ways of tweaking the pitch up or down by steps of ~1.5% which means no gear need be more than 0.7% out, which is fine for most real life applications.

If you get a run of readily usable gears in single steps near 66 teeth, say from 55 to 66 then for most pitches you will be able to incorporate two gears from the series allowing you to vary the pitch in steps of well under 0.1%, smaller than your machining accuracy.

Neil
10 October 2015 at 11:22 #207277
Ady1
Participant
@ady1
Added an error function to the program, in this case

0.0001 either side for 59tpi, changegears 20 to 65 with 59 excluded

The most useful thing is its speed, 2-3mins

(I have had speed problems with the plugging in gears program because of float/integer issues)

Found a match 59.000000 n[22.000000] n[23.000000] n[48.000000] n[47.000000] n[58.000000] n[63.000000]
Found a match 59.000000 n[22.000000] n[23.000000] n[48.000000] n[47.000000] n[63.000000] n[58.000000]
Found a match 59.000000 n[22.000000] n[47.000000] n[48.000000] n[23.000000] n[58.000000] n[63.000000]
Found a match 59.000000 n[22.000000] n[47.000000] n[48.000000] n[23.000000] n[63.000000] n[58.000000]
Found a match 59.000000 n[22.000000] n[23.000000] n[54.000000] n[47.000000] n[56.000000] n[58.000000]
Found a match 59.000000 n[22.000000] n[23.000000] n[54.000000] n[47.000000] n[58.000000] n[56.000000]
Found a match 59.000000 n[22.000000] n[47.000000] n[54.000000] n[23.000000] n[56.000000] n[58.000000]
Found a match 59.000000 n[22.000000] n[47.000000] n[54.000000] n[23.000000] n[58.000000] n[56.000000]
Found a match 59.000000 n[22.000000] n[23.000000] n[56.000000] n[47.000000] n[54.000000] n[58.000000]
Found a match 59.000000 n[22.000000] n[23.000000] n[56.000000] n[47.000000] n[58.000000] n[54.000000]
Found a match 59.000000 n[22.000000] n[47.000000] n[56.000000] n[23.000000] n[54.000000] n[58.000000]
Found a match 59.000000 n[22.000000] n[47.000000] n[56.000000] n[23.000000] n[58.000000] n[54.000000]
Found a match 59.000000 n[22.000000] n[23.000000] n[58.000000] n[47.000000] n[48.000000] n[63.000000]
Found a match 59.000000 n[22.000000] n[23.000000] n[58.000000] n[47.000000] n[54.000000] n[56.000000]
Found a match 59.000000 n[22.000000] n[23.000000] n[58.000000] n[47.000000] n[56.000000] n[54.000000]
Found a match 59.000000 n[22.000000] n[23.000000] n[58.000000] n[47.000000] n[63.000000] n[48.000000]
Found a match 59.000000 n[22.000000] n[47.000000] n[58.000000] n[23.000000] n[48.000000] n[63.000000]
Found a match 59.000000 n[22.000000] n[47.000000] n[58.000000] n[23.000000] n[54.000000] n[56.000000]
Found a match 59.000000 n[22.000000] n[47.000000] n[58.000000] n[23.000000] n[56.000000] n[54.000000]
Found a match 59.000000 n[22.000000] n[47.000000] n[58.000000] n[23.000000] n[63.000000] n[48.000000]
Found a match 59.000000 n[22.000000] n[23.000000] n[63.000000] n[47.000000] n[48.000000] n[58.000000]
Found a match 59.000000 n[22.000000] n[23.000000] n[63.000000] n[47.000000] n[58.000000] n[48.000000]
Found a match 59.000000 n[22.000000] n[47.000000] n[63.000000] n[23.000000] n[48.000000] n[58.000000]
Found a match 59.000000 n[22.000000] n[47.000000] n[63.000000] n[23.000000] n[58.000000] n[48.000000]
Found a match 59.000000 n[23.000000] n[22.000000] n[48.000000] n[47.000000] n[58.000000] n[63.000000]
Found a match 59.000000 n[23.000000] n[22.000000] n[48.000000] n[47.000000] n[63.000000] n[58.000000]
Found a match 59.000000 n[23.000000] n[47.000000] n[48.000000] n[22.000000] n[58.000000] n[63.000000]
Found a match 59.000000 n[23.000000] n[47.000000] n[48.000000] n[22.000000] n[63.000000] n[58.000000]
Found a match 59.000000 n[23.000000] n[22.000000] n[54.000000] n[47.000000] n[56.000000] n[58.000000]
Found a match 59.000000 n[23.000000] n[22.000000] n[54.000000] n[47.000000] n[58.000000] n[56.000000]
Found a match 59.000000 n[23.000000] n[47.000000] n[54.000000] n[22.000000] n[56.000000] n[58.000000]
Found a match 59.000000 n[23.000000] n[47.000000] n[54.000000] n[22.000000] n[58.000000] n[56.000000]
Found a match 59.000000 n[23.000000] n[22.000000] n[56.000000] n[47.000000] n[54.000000] n[58.000000]
Found a match 59.000000 n[23.000000] n[22.000000] n[56.000000] n[47.000000] n[58.000000] n[54.000000]
Found a match 59.000000 n[23.000000] n[47.000000] n[56.000000] n[22.000000] n[54.000000] n[58.000000]
Found a match 59.000000 n[23.000000] n[47.000000] n[56.000000] n[22.000000] n[58.000000] n[54.000000]
Found a match 59.000000 n[23.000000] n[22.000000] n[58.000000] n[47.000000] n[48.000000] n[63.000000]
Found a match 59.000000 n[23.000000] n[22.000000] n[58.000000] n[47.000000] n[54.000000] n[56.000000]
Found a match 59.000000 n[23.000000] n[22.000000] n[58.000000] n[47.000000] n[56.000000] n[54.000000]
Found a match 59.000000 n[23.000000] n[22.000000] n[58.000000] n[47.000000] n[63.000000] n[48.000000]
Found a match 59.000000 n[23.000000] n[47.000000] n[58.000000] n[22.000000] n[48.000000] n[63.000000]
Found a match 59.000000 n[23.000000] n[47.000000] n[58.000000] n[22.000000] n[54.000000] n[56.000000]
Found a match 59.000000 n[23.000000] n[47.000000] n[58.000000] n[22.000000] n[56.000000] n[54.000000]

There are about 170 combinations in total

Edited By Ady1 on 10/10/2015 11:32:48
10 October 2015 at 11:22 #207278
Ady1
Participant
@ady1
Found a match 59.000000 n[23.000000] n[47.000000] n[58.000000] n[22.000000] n[63.000000] n[48.000000]
Found a match 59.000000 n[23.000000] n[22.000000] n[63.000000] n[47.000000] n[48.000000] n[58.000000]
Found a match 59.000000 n[23.000000] n[22.000000] n[63.000000] n[47.000000] n[58.000000] n[48.000000]
Found a match 59.000000 n[23.000000] n[47.000000] n[63.000000] n[22.000000] n[48.000000] n[58.000000]

Found a match 59.000000 n[23.000000] n[47.000000] n[63.000000] n[22.000000] n[58.000000] n[48.000000]
Found a match 59.000000 n[25.000000] n[25.000000] n[44.000000] n[29.000000] n[49.000000] n[62.000000]
Found a match 59.000000 n[25.000000] n[25.000000] n[44.000000] n[29.000000] n[62.000000] n[49.000000]
Found a match 59.000000 n[25.000000] n[29.000000] n[44.000000] n[25.000000] n[49.000000] n[62.000000]
Found a match 59.000000 n[25.000000] n[29.000000] n[44.000000] n[25.000000] n[62.000000] n[49.000000]
Found a match 59.000000 n[25.000000] n[25.000000] n[49.000000] n[29.000000] n[44.000000] n[62.000000]
Found a match 59.000000 n[25.000000] n[25.000000] n[49.000000] n[29.000000] n[62.000000] n[44.000000]
Found a match 59.000000 n[25.000000] n[29.000000] n[49.000000] n[25.000000] n[44.000000] n[62.000000]
Found a match 59.000000 n[25.000000] n[29.000000] n[49.000000] n[25.000000] n[62.000000] n[44.000000]
Found a match 59.000000 n[25.000000] n[25.000000] n[62.000000] n[29.000000] n[44.000000] n[49.000000]
Found a match 59.000000 n[25.000000] n[25.000000] n[62.000000] n[29.000000] n[49.000000] n[44.000000]

Found a match 59.000000 n[25.000000] n[29.000000] n[62.000000] n[25.000000] n[44.000000] n[49.000000]
Found a match 59.000000 n[25.000000] n[29.000000] n[62.000000] n[25.000000] n[49.000000] n[44.000000]
Found a match 59.000000 n[26.000000] n[29.000000] n[51.000000] n[29.000000] n[51.000000] n[62.000000]
Found a match 59.000000 n[26.000000] n[29.000000] n[51.000000] n[29.000000] n[62.000000] n[51.000000]
Found a match 59.000000 n[26.000000] n[29.000000] n[62.000000] n[29.000000] n[51.000000] n[51.000000]
Found a match 58.999916 n[22.000000] n[23.000000] n[48.000000] n[47.000000] n[58.000000] n[63.000000]
Found a match 58.999916 n[22.000000] n[23.000000] n[48.000000] n[47.000000] n[63.000000] n[58.000000]
Found a match 58.999916 n[22.000000] n[47.000000] n[48.000000] n[23.000000] n[58.000000] n[63.000000]
Found a match 58.999920 n[22.000000] n[47.000000] n[48.000000] n[23.000000] n[63.000000] n[58.000000]
Found a match 58.999920 n[22.000000] n[23.000000] n[54.000000] n[47.000000] n[56.000000] n[58.000000]
Found a match 58.999920 n[22.000000] n[23.000000] n[54.000000] n[47.000000] n[58.000000] n[56.000000]
Found a match 58.999920 n[22.000000] n[47.000000] n[54.000000] n[23.000000] n[56.000000] n[58.000000]
Found a match 58.999920 n[22.000000] n[47.000000] n[54.000000] n[23.000000] n[58.000000] n[56.000000]
Found a match 58.999916 n[22.000000] n[23.000000] n[56.000000] n[47.000000] n[54.000000] n[58.000000]

Found a match 58.999916 n[22.000000] n[23.000000] n[56.000000] n[47.000000] n[58.000000] n[54.000000]
Found a match 58.999920 n[22.000000] n[47.000000] n[56.000000] n[23.000000] n[54.000000] n[58.000000]
Found a match 58.999920 n[22.000000] n[47.000000] n[56.000000] n[23.000000] n[58.000000] n[54.000000]
Found a match 58.999916 n[22.000000] n[23.000000] n[58.000000] n[47.000000] n[48.000000] n[63.000000]
Found a match 58.999912 n[22.000000] n[23.000000] n[58.000000] n[47.000000] n[54.000000] n[56.000000]
Found a match 58.999916 n[22.000000] n[23.000000] n[58.000000] n[47.000000] n[56.000000] n[54.000000]
Found a match 58.999916 n[22.000000] n[23.000000] n[58.000000] n[47.000000] n[63.000000] n[48.000000]
Found a match 58.999916 n[22.000000] n[47.000000] n[58.000000] n[23.000000] n[48.000000] n[63.000000]
Found a match 58.999912 n[22.000000] n[47.000000] n[58.000000] n[23.000000] n[54.000000] n[56.000000]
Found a match 58.999912 n[22.000000] n[47.000000] n[58.000000] n[23.000000] n[56.000000] n[54.000000]
Found a match 58.999912 n[22.000000] n[47.000000] n[58.000000] n[23.000000] n[63.000000] n[48.000000]
Found a match 58.999916 n[22.000000] n[23.000000] n[63.000000] n[47.000000] n[48.000000] n[58.000000]
Found a match 58.999916 n[22.000000] n[23.000000] n[63.000000] n[47.000000] n[58.000000] n[48.000000]
Found a match 58.999916 n[22.000000] n[47.000000] n[63.000000] n[23.000000] n[48.000000] n[58.000000]
Found a match 58.999916 n[22.000000] n[47.000000] n[63.000000] n[23.000000] n[58.000000] n[48.000000]
Found a match 58.999916 n[23.000000] n[22.000000] n[48.000000] n[47.000000] n[58.000000] n[63.000000]
Found a match 58.999916 n[23.000000] n[22.000000] n[48.000000] n[47.000000] n[63.000000] n[58.000000]
Found a match 58.999916 n[23.000000] n[47.000000] n[48.000000] n[22.000000] n[58.000000] n[63.000000]
Found a match 58.999916 n[23.000000] n[47.000000] n[48.000000] n[22.000000] n[63.000000] n[58.000000]
Found a match 58.999920 n[23.000000] n[22.000000] n[54.000000] n[47.000000] n[56.000000] n[58.000000]
Found a match 58.999920 n[23.000000] n[22.000000] n[54.000000] n[47.000000] n[58.000000] n[56.000000]
Found a match 58.999916 n[23.000000] n[47.000000] n[54.000000] n[22.000000] n[56.000000] n[58.000000]
Found a match 58.999916 n[23.000000] n[47.000000] n[54.000000] n[22.000000] n[58.000000] n[56.000000]
Found a match 58.999916 n[23.000000] n[22.000000] n[56.000000] n[47.000000] n[54.000000] n[58.000000]
Found a match 58.999916 n[23.000000] n[22.000000] n[56.000000] n[47.000000] n[58.000000] n[54.000000]

Edite
10 October 2015 at 11:23 #207280
Ady1
Participant
@ady1
Found a match 58.999916 n[23.000000] n[47.000000] n[56.000000] n[22.000000] n[54.000000] n[58.000000]
Found a match 58.999916 n[23.000000] n[47.000000] n[56.000000] n[22.000000] n[58.000000] n[54.000000]
Found a match 58.999916 n[23.000000] n[22.000000] n[58.000000] n[47.000000] n[48.000000] n[63.000000]
Found a match 58.999912 n[23.000000] n[22.000000] n[58.000000] n[47.000000] n[54.000000] n[56.000000]
Found a match 58.999916 n[23.000000] n[22.000000] n[58.000000] n[47.000000] n[56.000000] n[54.000000]
Found a match 58.999916 n[23.000000] n[22.000000] n[58.000000] n[47.000000] n[63.000000] n[48.000000]
Found a match 58.999916 n[23.000000] n[47.000000] n[58.000000] n[22.000000] n[48.000000] n[63.000000]
Found a match 58.999912 n[23.000000] n[47.000000] n[58.000000] n[22.000000] n[54.000000] n[56.000000]
Found a match 58.999912 n[23.000000] n[47.000000] n[58.000000] n[22.000000] n[56.000000] n[54.000000]
Found a match 58.999912 n[23.000000] n[47.000000] n[58.000000] n[22.000000] n[63.000000] n[48.000000]
Found a match 58.999916 n[23.000000] n[22.000000] n[63.000000] n[47.000000] n[48.000000] n[58.000000]
Found a match 58.999916 n[23.000000] n[22.000000] n[63.000000] n[47.000000] n[58.000000] n[48.000000]
Found a match 58.999920 n[23.000000] n[47.000000] n[63.000000] n[22.000000] n[48.000000] n[58.000000]
Found a match 58.999920 n[23.000000] n[47.000000] n[63.000000] n[22.000000] n[58.000000] n[48.000000]
Found a match 59.000057 n[25.000000] n[25.000000] n[44.000000] n[29.000000] n[49.000000] n[62.000000]
Found a match 59.000057 n[25.000000] n[25.000000] n[44.000000] n[29.000000] n[62.000000] n[49.000000]
Found a match 59.000057 n[25.000000] n[29.000000] n[44.000000] n[25.000000] n[49.000000] n[62.000000]
Found a match 59.000061 n[25.000000] n[29.000000] n[44.000000] n[25.000000] n[62.000000] n[49.000000]
Found a match 59.000057 n[25.000000] n[25.000000] n[49.000000] n[29.000000] n[44.000000] n[62.000000]
Found a match 59.000053 n[25.000000] n[25.000000] n[49.000000] n[29.000000] n[62.000000] n[44.000000]
Found a match 59.000057 n[25.000000] n[29.000000] n[49.000000] n[25.000000] n[44.000000] n[62.000000]
Found a match 59.000057 n[25.000000] n[29.000000] n[49.000000] n[25.000000] n[62.000000] n[44.000000]
Found a match 59.000050 n[25.000000] n[25.000000] n[62.000000] n[29.000000] n[44.000000] n[49.000000]
Found a match 59.000053 n[25.000000] n[25.000000] n[62.000000] n[29.000000] n[49.000000] n[44.000000]
Found a match 59.000057 n[25.000000] n[29.000000] n[62.000000] n[25.000000] n[44.000000] n[49.000000]
Found a match 59.000057 n[25.000000] n[29.000000] n[62.000000] n[25.000000] n[49.000000] n[44.000000]
Found a match 59.000088 n[26.000000] n[29.000000] n[51.000000] n[29.000000] n[51.000000] n[62.000000]
Found a match 59.000092 n[26.000000] n[29.000000] n[51.000000] n[29.000000] n[62.000000] n[51.000000]
Found a match 59.000092 n[26.000000] n[29.000000] n[62.000000] n[29.000000] n[51.000000] n[51.000000]

Edited By Ady1 on 10/10/2015 11:34:18
10 October 2015 at 11:23 #207281
Ady1
Participant
@ady1
Found a match 59.000057 n[29.000000] n[25.000000] n[44.000000] n[25.000000] n[49.000000] n[62.000000]
Found a match 59.000061 n[29.000000] n[25.000000] n[44.000000] n[25.000000] n[62.000000] n[49.000000]
Found a match 59.000057 n[29.000000] n[25.000000] n[49.000000] n[25.000000] n[44.000000] n[62.000000]
Found a match 59.000057 n[29.000000] n[25.000000] n[49.000000] n[25.000000] n[62.000000] n[44.000000]
Found a match 59.000088 n[29.000000] n[26.000000] n[51.000000] n[29.000000] n[51.000000] n[62.000000]
Found a match 59.000092 n[29.000000] n[26.000000] n[51.000000] n[29.000000] n[62.000000] n[51.000000]
Found a match 59.000088 n[29.000000] n[29.000000] n[51.000000] n[26.000000] n[51.000000] n[62.000000]
Found a match 59.000092 n[29.000000] n[29.000000] n[51.000000] n[26.000000] n[62.000000] n[51.000000]
Found a match 59.000057 n[29.000000] n[25.000000] n[62.000000] n[25.000000] n[44.000000] n[49.000000]
Found a match 59.000057 n[29.000000] n[25.000000] n[62.000000] n[25.000000] n[49.000000] n[44.000000]
Found a match 59.000092 n[29.000000] n[26.000000] n[62.000000] n[29.000000] n[51.000000] n[51.000000]
Found a match 59.000092 n[29.000000] n[29.000000] n[62.000000] n[26.000000] n[51.000000] n[51.000000]
Found a match 58.999916 n[47.000000] n[22.000000] n[48.000000] n[23.000000] n[58.000000] n[63.000000]
Found a match 58.999920 n[47.000000] n[22.000000] n[48.000000] n[23.000000] n[63.000000] n[58.000000]
Found a match 58.999916 n[47.000000] n[23.000000] n[48.000000] n[22.000000] n[58.000000] n[63.000000]
Found a match 58.999916 n[47.000000] n[23.000000] n[48.000000] n[22.000000] n[63.000000] n[58.000000]
Found a match 58.999920 n[47.000000] n[22.000000] n[54.000000] n[23.000000] n[56.000000] n[58.000000]
Found a match 58.999920 n[47.000000] n[22.000000] n[54.000000] n[23.000000] n[58.000000] n[56.000000]
Found a match 58.999916 n[47.000000] n[23.000000] n[54.000000] n[22.000000] n[56.000000] n[58.000000]
Found a match 58.999916 n[47.000000] n[23.000000] n[54.000000] n[22.000000] n[58.000000] n[56.000000]
Found a match 58.999920 n[47.000000] n[22.000000] n[56.000000] n[23.000000] n[54.000000] n[58.000000]
Found a match 58.999920 n[47.000000] n[22.000000] n[56.000000] n[23.000000] n[58.000000] n[54.000000]
Found a match 58.999916 n[47.000000] n[23.000000] n[56.000000] n[22.000000] n[54.000000] n[58.000000]
Found a match 58.999916 n[47.000000] n[23.000000] n[56.000000] n[22.000000] n[58.000000] n[54.000000]
Found a match 58.999916 n[47.000000] n[22.000000] n[58.000000] n[23.000000] n[48.000000] n[63.000000]
Found a match 58.999912 n[47.000000] n[22.000000] n[58.000000] n[23.000000] n[54.000000] n[56.000000]
Found a match 58.999912 n[47.000000] n[22.000000] n[58.000000] n[23.000000] n[56.000000] n[54.000000]
Found a match 58.999912 n[47.000000] n[22.000000] n[58.000000] n[23.000000] n[63.000000] n[48.000000]
Found a match 58.999916 n[47.000000] n[23.000000] n[58.000000] n[22.000000] n[48.000000] n[63.000000]
Found a match 58.999912 n[47.000000] n[23.000000] n[58.000000] n[22.000000] n[54.000000] n[56.000000]
Found a match 58.999912 n[47.000000] n[23.000000] n[58.000000] n[22.000000] n[56.000000] n[54.000000]
Found a match 58.999912 n[47.000000] n[23.000000] n[58.000000] n[22.000000] n[63.000000] n[48.000000]
Found a match 58.999916 n[47.000000] n[22.000000] n[63.000000] n[23.000000] n[48.000000] n[58.000000]
Found a match 58.999916 n[47.000000] n[22.000000] n[63.000000] n[23.000000] n[58.000000] n[48.000000]
Found a match 58.999920 n[47.000000] n[23.000000] n[63.000000] n[22.000000] n[48.000000] n[58.000000]
Found a match 58.999920 n[47.000000] n[23.000000] n[63.000000] n[22.000000] n[58.000000] n[48.000000]

Edited By Ady1 on 10/10/2015 11:35:13
13 October 2015 at 11:41 #207622
Ady1
Participant
@ady1
Introducing an "allowable error" makes things miles easier

Using a gearset of

20 25 30 35 40 46 50 55 60 63 65

for 25.4tpi on an 8tpi leadscrew and 0.001 error gives almost 400 returns

Found a match 25.396826 n[63.000000] n[20.000000] n[60.000000] n[30.000000] n[40.000000] n[50.000000]
Found a match 25.396824 n[63.000000] n[20.000000] n[60.000000] n[30.000000] n[50.000000] n[40.000000]
Found a match 25.396826 n[63.000000] n[25.000000] n[60.000000] n[30.000000] n[50.000000] n[50.000000]
Found a match 25.396826 n[63.000000] n[30.000000] n[60.000000] n[20.000000] n[40.000000] n[50.000000]
Found a match 25.396824 n[63.000000] n[30.000000] n[60.000000] n[20.000000] n[50.000000] n[40.000000]
Found a match 25.396826 n[63.000000] n[30.000000] n[60.000000] n[25.000000] n[50.000000] n[50.000000]
Found a match 25.396826 n[63.000000] n[30.000000] n[60.000000] n[30.000000] n[50.000000] n[60.000000]
Found a match 25.396826 n[63.000000] n[30.000000] n[60.000000] n[30.000000] n[60.000000] n[50.000000]
Found a match 25.401600 n[63.000000] n[25.000000] n[63.000000] n[50.000000] n[63.000000] n[63.000000]
Found a match 25.401600 n[63.000000] n[50.000000] n[63.000000] n[25.000000] n[63.000000] n[63.000000]
Found a match 25.401600 n[65.000000] n[25.000000] n[63.000000] n[50.000000] n[63.000000] n[65.000000]
Found a match 25.401600 n[65.000000] n[25.000000] n[63.000000] n[50.000000] n[65.000000] n[63.000000]
Found a match 25.401600 n[65.000000] n[50.000000] n[63.000000] n[25.000000] n[63.000000] n[65.000000]
Found a match 25.401600 n[65.000000] n[50.000000] n[63.000000] n[25.000000] n[65.000000] n[63.000000]
Found a match 25.401600 n[65.000000] n[25.000000] n[65.000000] n[50.000000] n[63.000000] n[63.000000]
Found a match 25.401600 n[65.000000] n[50.000000] n[65.000000] n[25.000000] n[63.000000] n[63.000000]
13 October 2015 at 11:49 #207623
Ady1
Participant
@ady1
Even the elusive 59tpi becomes possible on a crappy gearset with an error of 0.01

58.996361 n[25.000000] n[25.000000] n[60.000000] n[55.000000] n[65.000000] n[65.000000]
58.996365 n[25.000000] n[55.000000] n[60.000000] n[25.000000] n[65.000000] n[65.000000]
58.996361 n[25.000000] n[25.000000] n[65.000000] n[55.000000] n[60.000000] n[65.000000]
58.996361 n[25.000000] n[25.000000] n[65.000000] n[55.000000] n[65.000000] n[60.000000]
58.996361 n[25.000000] n[55.000000] n[65.000000] n[25.000000] n[60.000000] n[65.000000]
58.996361 n[25.000000] n[55.000000] n[65.000000] n[25.000000] n[65.000000] n[60.000000]
58.996365 n[55.000000] n[25.000000] n[60.000000] n[25.000000] n[65.000000] n[65.000000]
58.996361 n[55.000000] n[25.000000] n[65.000000] n[25.000000] n[60.000000] n[65.000000]
58.996361 n[55.000000] n[25.000000] n[65.000000] n[25.000000] n[65.000000] n[60.000000]
13 October 2015 at 12:11 #207625
Bazyle
Participant
@bazyle
Well I for one have no idea what you're on about. Got lost half a million decimal points ago.
13 October 2015 at 13:14 #207631
John Stevenson 1
Participant
@johnstevenson1
Your maths is way out.

58.996361 n[55.000000] n[25.000000] n[65.000000] n[25.000000] n[60.000000] n[65.000000]
58.996361 n[55.000000] n[25.000000] n[65.000000] n[25.000000] n[65.000000] n[60.000000]

No way you can reverse the last two gears and still have the same ratio
13 October 2015 at 13:31 #207639
Neil Wyatt
Moderator
@neilwyatt
Problem is here:

Also some have the same issue with teh first two gears eg

59-23, 50-59, 62-82 can't be the same as

23-59, 50-59, 62-82 can it?

———————————–

59 23-50 59-62 82

23 59-50 59-62 82

first:

(23/50)*59=27.14

(59/62)*27.14=25.82677

82/25.82677=3.17499

3.17499*8tpi=25.3999tpi

second:

(59/50)*23=27.14

(59/62)*27.14=25.82677

82/25.82677=3.17499

3.17499*8=25.3999tpi

It all seems ok to me, (only playing about though)

It looks to me like you are not calculating the ratios correctly (you have got some of the ratios upside down). I get the two setups to give completely different ratios;

59 23-50 59-62 82

(59*50*62)/(23*59*82) = 1.6437

23 59-50 59-62 82

(23*50*62)/(59*59*82) = 0.2498

Neil

Edited By Neil Wyatt on 13/10/2015 13:33:25
Author

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