# New index for Harold Hall's web site.



## workshopman (Jul 28, 2012)

I know some who visit this forum also occasionally visit my web site and may find the following of interest.

My website having grown far beyond what I first envisaged I began to realise the method of finding items in the metalworking section was far from adequate. Basically, I had kept the projects and processes separate and listed them just in the order that I added them to the site. This resulted in them being in totally random order, I am sure many of you have realised this.

I decided therefore that a book style index, being in alphabetical order, would be a great improvement, especially as I was even finding it a problem sometimes to locate a page myself. 

In doing this, I have amalgamated both the projects and processes in a single index. However, it is easy to determine if an entry is a project or a process as I have used different coloured buttons with inscriptions that make this clear. 

Making the change has also enabled an item to be index with differing titles, typically, &#8220;Three jaw chuck soft jaws&#8221; and &#8220;Soft jaws for a three jaw chuck&#8221; making it less important where in the index an item is searched for.

Also, I have now indexed items embedded within pages on another subject. For example, pages mainly on making a Tee slot cutter may have a few paragraphs on hardening and tempering, both can now be listed. 

To avoid having to update two listings the original lists have been deleted. However, if you have bookmarked the lists the pages still exist but just with a link to take you to the new indexes.

The task has been a time consuming and complex one and it is almost inevitable that I have made a few errors. Should you find a link takes you nowhere or to the wrong page then do feel free to put me in my place. I do though intend to double check its content over the next few weeks.

Hope you find the new index useful!

The index can be found here http://www.homews.co.uk/page463.html

SEE POST BELOW FOR A WORKING LINK!

Harold


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## kuhncw (Jul 28, 2012)

Harold, thank you for developing this index and posting it.

Regards,

Chuck


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## edtherom (Jul 28, 2012)

I get a 404 when I click on it.


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## kellswaterri (Jul 28, 2012)

Hi Harry, link broken...
                             John.


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## sssfox (Jul 28, 2012)

For some reason, it posts http://www.homemodelenginemachinist.com/ to the beginning of the address.
If you delete that, it works.


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## Journeyman (Jul 28, 2012)

Hi Harold
The link text is correct but the embedded bit seems to have added the HMEM link to it so that the whole thing reads:
http://www.homemodelenginemachinist.com/www.homews.co.uk/page463.html
which obviously doesn't make sense!

Cheers, John


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## kellswaterri (Jul 28, 2012)

cutting and pasteing to Google works for me.


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## workshopman (Jul 28, 2012)

Sorry, had exactly the same problem described by John with the UK ME forum at one time. Let's try again. If it does not work please cut and paste as kellswaterri suggests, in which case, perhaps someone more used to this forum may like to explain how it can be done and paste the link for me.
Try http://www.homews.co.uk/page463.html

Harold


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## wheeltapper (Jul 28, 2012)

Works for me. Great job.
Roy


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## dsquire (Jul 28, 2012)

workshopman said:


> Sorry, had exactly the same problem described by John with the UK ME forum at one time. Let's try again. If it does not work please cut and paste as kellswaterri suggests, in which case, perhaps someone more used to this forum may like to explain how it can be done and paste the link for me.
> Try http://www.homews.co.uk/page463.html
> 
> Harold


 

I added *http://* to the beginning of the link and it works. I edited the file for you.

Thanks for provideing the link and indexing the files.

Cheers 

Don


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## lemelman (Aug 6, 2012)

Hi Harold,
The "ChangewheelSetup_1.pdf" referenced in the Screw Cutting pages would make more sense if you labelled the gears to match the designations R1 R2 R3 N1 N2 N3 of the Changewheel Combinations charts. As it stands, there is no correspondence between  gears A, B, C, D, E, F, and R1, R2, R3, N1, N2, N3.


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## workshopman (Aug 15, 2012)

I think that I should first, as the subject  Gary and I are discussing is a diversion from this thread, explain to other viewers the background.


 I wrote some years back a program that would calculate the threads per inch achieved for every possible combination of 14 gears. This being over 66.000. From these I select only those values between 6 and 50tpi, still resulting in 37.293 combinations.  These I list on my website.


 The lists show that there are in almost all cases many combinations that achieve the same result, ideal for the workshop owner who does not have a complete set of changewheels.  Also, if cutting a metric thread, or turning a worm gear, there are many values that are very close to the precise metric pitch required.     


 As an example, if wishing to cut 2BA (yes they are metric) having a pitch of 0.81mm there are 6 combinations giving 31.3596 tpi This equates to a pitch of 0.80996mm an error of 0.00004mm. If gears are not available there are many others almost as accurate.


 The lists do though only quote the drivers and driven leaving it to the workshop owner to choose how they are arranged on the quadrant. However, there is a drawing that suggests the most likely approach to come up with a suitable arrangement.


 The pages also list combinations for those who have a lathe with a metric leadscrew


 The site is at  at  www.homews.co.uk/page28.html 

 I will publish my comments to Gary in the following entry.

Harold


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## workshopman (Aug 15, 2012)

I am sorry Gary for having been so long in replying to your post but other things have been demanding my attention for a few days. 

 I, like you, would prefer the listing to define the actual order of the gears to be placed onto the lathes quadrant. Unfortunately, this would add an additional layer of complication to the program.  Also, as I will attempt to explain, it would not be straight forward.


 First, to ensure that every possible combination is arranged and calculated, the program has to sequence through the available gears in a logical manner, I will try to explain.


 If we take the six gears, that's three drivers and three driven, and place the six smallest gears in them in sequence a resulting TPI can be calculated. If then the third driven is increased by one size a further TPI value can be calculated, this then repeated until the third driven reaches the 14th and largest gear.


 Next, the third driver can be upped one size and the sequence again repeated with the third driven. This process being repeated until we get back to the first driver which still has the smallest available gear in that position.  From here the first driver is upped one size and the whole process repeated, and continually repeated until a calculation is finally made with the six largest gears. This can be seen from the published lists as, for each combination, the three drivers and the three driven are each in a order of smallest first and the largest third.  Its a little more complex than that but this gives the basic idea.


 At this stage we now have a list in excess of 66000 combinations but with the resulting TPI values in random order. This then is sorted to so that we end up with a logical listing, smallest to largest TPI values that is .


 As is obvious from the above this can in no way represent the order the gears are placed onto the quadrant, if this had been attempted within this process it would be so easy to miss out some combinations.


 The program could then be extended to see how each combination could be fitted to the quadrant. However, as most of the combinations could be arranged on the quadrant in more than sequence the final listing could be doubled or even tripled. Of course, some criterion could be established to review each combination  and choose only one but all this is a non starter for three reasons.


 1. It is now over 20 years since I wrote the program, which was done whilst editor of MEW, and passed the code onto another when I left. It was a DOS program and all I now have is a compiled copy.  


 2. If I had the code it is doubtful if my brain is now agile enough to achieve the required result in a reasonable time.  


 3. There maybe some lathes that have peculiar changewheel arrangements that may not suit the norm.  


 My drawing is mainly intended to show the basic requirements, which engage and where there must be clearance. Admittedly, I do show a combination with the three drivers in reverse order to my listing and could then have given them the same references Dr1, Dn1, etc. rather than A, B,  etc. but that would imply that that order would work every time. This I am not sure.


 To prove a setup will work you do not have to actually fit them to the quadrant, just couple the pairs together and lay them on the bench engaging the gear that you wish to. Then, check there is clearance between the gears where required, if OK transfer them to the lathe.  


 Harold


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