Lo-Fi's dividing head calculator

Lo-Fi

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H-M Supporter - Silver Member
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Dec 23, 2019
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Not your usual project here, I know, but I got fed up with using incomplete charts and manually figuring out what I can and can't divide with the plates I have, so I've been coding up a calculator!

You feed it a list of hole patterns you have available and the ratio of your dividing head, then what you want to divide and it'll tell you if it's possible, which plate to choose and how many turns/holes. If there are multiple solutions, it'll list them. The really clever stuff is yet to come - it'll calculate differential dividing too for divisions you can't get with plates alone if fed a list of change gears.

Windows only, as I'm already familiar with C# and Visual Studio, but it ought to be easy enough to port if someone feels like it. I'll open source it with a free pre-compiled executable once I'm happy that it's at least good enough for an initial release. Hooray for these wonderful software development tools being FREE!

Excellent video on differential dividing here:


I'm really excited to get cutting some gears :)

Stay tuned!
 
Quick screen grab. Early stages yet, but it's working for simple dividing.

Dividing Calc.PNG
 

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Just realised a few posts in this thread got lost in the great forum outage, and I've developed it further from there anyway.

You can manually add your hole patterns, or import from a CSV file. Same with gears if you've got a dividing head that takes change gears for differential indexing like mine:

1.PNG

You can set your dividing head ratio, though it defaults to 40:1 as that seems most common.

Enter what you'd like to index by and it'll do all the calcs based on what you've told it you have and show what's possible. The row in bold shows that we need to use the 31 hole plate, rotating one full turn and 9 holes to achieve that:

2.PNG

If multiple solutions are possible, it'll show that too:

3.PNG

We can use the 21 or 33 hole plate to index 30 divisions.

Here's a case which can't be simple indexed. But it can be differential indexed with the available plates and gears:

4.PNG

The "Approx" field shows what we'd set up for as approximate simple indexing, with the gear setup outlined in the bottom right. The reverse rotation field shows if an extra idler is needed to reverse the rotation between the spindle and plate.

Kinda cool, but laborious if you're trying to figure out what you can and can't do. So here comes the clever stuff. Clicking on the "gear info" button brings up another form where you can specify a range of gear sizes (though you can ignore that they're "gears" if you're indexing something else) and a table will be generated showing in bold those tooth counts that can be simple indexed and bold italic for those that can't, but can be differential indexed.

5.PNG

It's set up to show info for metric gears, so you can change the module field and the table gets updated with the relevant info. I should probably add a few more fields in.

Selecting two rows will give the correct centre distance for those two gears.

7.PNG

Double clicking on a row will set the first form up with info for that indexing job.

I'm working on getting it to suggest which plates might be most helpful for plugging the gaps in your current collection.

Still double checking it, but I'll release it soon open source once I'm happy I'm not giving out garbage info. It's been spot on for me so far! All but one of these (the one that came with the dividing head) has been cut with info out of the app.

2020-02-06 19.51.14.jpg

Including the 39 tooth which was differential indexed!

2020-02-06 19.43.09-1.jpg

Tables now seem very tedious...

TTFN :D
 
So whatever happened to this? I was just sitting down to code one of these things myself, because I'm tired of using spreadsheets of unknown provenance that aren't designed well.
 
It verks!

Happy to send over. Code is super hacky as I've not got round to doing anything about that, but you're very welcome to it.
 
Actually, you'll appreciate this, @dewbane ... That 39 tooth wheel turns out to be a 41 tooth wheel because I forgot to add an idler gear while differential indexing, so it added 1/40 of a turn each time, rather than subtracting.
 
Actually, you'll appreciate this, @dewbane ... That 39 tooth wheel turns out to be a 41 tooth wheel because I forgot to add an idler gear while differential indexing, so it added 1/40 of a turn each time, rather than subtracting.

I no longer feel so alone!

If you want to shoot the code to rosegarden.trumpeter@gmail.com I'll take a gander.

Wow. I was going to brag on my "kudo rank" in the open source community, but my reputation has gone swirling down the loo. I used to be second only to Linus Torvalds, and now I'm just a random nobody. I guess they made their algorithm smarter. It correctly recognizes the fact that I am a mere has-been as a code jockey.
 
Lol! I rake it out and send over :)

Really should open source it, I suppose. It'll be all the better for it.
 
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