5 ms·

Gear Generator

150 points by danshapiro 11y ago

danshapiro 11y ago
The best part of this is that you can output the gears as SVGs. For example, gear + Glowforge = http://community.glowforge.com/t/gears/143/4 http://community.glowforge.com/t/gears/143/4
- exodust 11y ago
  Wow, okay... that just happened. Instead of wanting a 3D printer, I now want one of these 3D laser printers. Tested video gives a good overview... youtu.be/0R3mMUsHFvU Need to see more reviews showing negative aspects. There's always negatives. Edit: found a negative: shipping price. To Australia it's US$1380 for the model with air filter. That's crazy. Almost 2 grand Australian dollars for shipping.
  - danshapiro 11y ago
    Founder/CEO here (the guy in the Tested video). Happy to answer any questions! Shipping stinks - we don't make a penny on it; it's just expensive to send big boxes around the world.
    - exodust 11y ago
      Ok thanks. This thread was about the gear generator so I won't ask anything here. I'll go to glowforge.com if I need to know more.
11thEarlOfMar 11y ago
Sweet. Do you have an example of a planetary gear reduction?
- danshapiro 11y ago
  Funny you should ask - I made a friend a laser cut model of his Prius transmission for his birthday. Cutting it (on a pre-Glowforge laser): https://goo.gl/photos/pxJKDipWPtj6RXvZ7 https://goo.gl/photos/pxJKDipWPtj6RXvZ7 Results: https://goo.gl/photos/NUivutAWsQe3GHfW8 https://goo.gl/photos/NUivutAWsQe3GHfW8
  - 11thEarlOfMar 11y ago
    Nice!
unwind 11y ago
Looks fantastic, and was seriously fun to fiddle a bit with. One bug though: you can't back out from the site, the history is flooded with geargenerator.com addresses. Had to close the tab (Firefox 40.0.3 on Windows).
- dspillett 11y ago
  > the history is flooded with geargenerator.com addresses I'm seeing this a lot in apps these days. In many places I think it is intentional: where the entire state of the current view can be encoded in the URL it effectively gives you a "free" undo feature and can be quite useful (like when I'm playing with potential new running routes in Google maps).
  - peterclary 11y ago
    Yes, and that can be useful. However, if you use the back button to return to a previous URL it doesn't appear to update the settings from the URL. This means you can't use the back button as an Undo button.
    - degenerate 11y ago
      Agree - I'd much prefer an "undo/redo" button inside the app, instead of flooding my history state. They can change the URL all they want (for linkability) but leave my damn history alone!
osullivj 11y ago
Very cool! The guys at http://romaxtech.com http://romaxtech.com should take a look at this...
amelius 11y ago
One thing I'm wondering about: do opposing gears always need to have the same form for the teeth? Also, what are the constraints that lead to the form of the teeth? I can imagine that one constraint is that the teeth must "roll" onto each other. But are there more constraints?
- fnordfnordfnord 11y ago
  The "rounded" design allows constant contact to be maintained between two gears. If they were of the simpler design with flat faces on the teeth, they would simply wear to this shape anyway, but in the process they would also end up with slack between them. A helical twist is also usually employed which improves the transition between adjacent teeth, and consequently reduces noise. Ever hear a transmission with a loud whine in reverse gear? IIRC, it's because they didn't use the helical twist trick on the reverse gear. I have no idea why they wouldn't though. If we're lucky, an ME will be along in a bit and explain all of this for us much better.
  - Asbostos 11y ago
    Yep. Straight cut gears are cheaper to make. Since people don't do as much reversing as going forward, it's probably a good compromise on cost vs comfort.
    - fnordfnordfnord 11y ago
      Makes sense to me.
- msandford 11y ago
  Opposing gears don't have the same form unless they have the same number of teeth. This isn't obvious when you look at the first gear pair, but look at the pair doing the 10:1 reduction. The teeth of the small gear are undercut quite a bit while the teeth on the big gear aren't undercut at all. The only real constraint is that the teeth must roll into one another as you concluded.
- IshKebab 11y ago
peterclary 11y ago
This is amazing! Well done and thank you!
KaiserPro 11y ago
This is majestic. I've been battling with making my own gears in Modo for a while (the inbuilt primitive scales the teeth size as well as number of teeth) However this allows me to create ratios AND test them at the same time. This is invaluable. When I get time I shall be using this for my laser cuttings.
phkahler 11y ago
Is that correct? The tip of the gear tooth seems to rub up against the other as it approaches. Shouldn't there be a small clearance there? or is there? Also, is there a way to export to a format that can be loaded into SolveSpace?
- Asbostos 11y ago
  Any clearance there would result in backlash. I suppose you need some to allow for manufacturing tolerance though.
  - phkahler 11y ago
    That's fine, but when I first looked at it, it seemed like they were sliding. Now I see that it may be rolling as desired.
fnordfnordfnord 11y ago
Neat. Now I want to be able to give the gears mass, and configure the "engine's" power output; and or maybe helical gear teeth.
jonjenk 11y ago
I've created a lot of 3D printed gears over the last few years and one of the best tools I've found is from Rainer Hessmer. http://hessmer.org/gears/InvoluteSpurGearBuilder.html http://hessmer.org/gears/InvoluteSpurGearBuilder.html It allows you to specify additional parameters like backlash, clearance, and profile shift. It also allows you to output in DXF which tends to be more of a standard in the engineering world.
oldpond 11y ago
Very nice.
crome 11y ago
Here s a referral link you can use to get 100$ off, im super stoked on this!! :) http://glowforge.com/referred/?kid=kmrbvD http://glowforge.com/referred/?kid=kmrbvD

150 points by danshapiro 11y ago

The best part of this is that you can output the gears as SVGs. For example, gear + Glowforge = http://community.glowforge.com/t/gears/143/4 http://community.glowforge.com/t/gears/143/4

exodust 11y ago
Wow, okay... that just happened. Instead of wanting a 3D printer, I now want one of these 3D laser printers. Tested video gives a good overview... youtu.be/0R3mMUsHFvU Need to see more reviews showing negative aspects. There's always negatives. Edit: found a negative: shipping price. To Australia it's US$1380 for the model with air filter. That's crazy. Almost 2 grand Australian dollars for shipping.
- danshapiro 11y ago
  Founder/CEO here (the guy in the Tested video). Happy to answer any questions! Shipping stinks - we don't make a penny on it; it's just expensive to send big boxes around the world.
  - exodust 11y ago
    Ok thanks. This thread was about the gear generator so I won't ask anything here. I'll go to glowforge.com if I need to know more.

11thEarlOfMar 11y ago

Sweet. Do you have an example of a planetary gear reduction?

danshapiro 11y ago
Funny you should ask - I made a friend a laser cut model of his Prius transmission for his birthday. Cutting it (on a pre-Glowforge laser): https://goo.gl/photos/pxJKDipWPtj6RXvZ7 https://goo.gl/photos/pxJKDipWPtj6RXvZ7 Results: https://goo.gl/photos/NUivutAWsQe3GHfW8 https://goo.gl/photos/NUivutAWsQe3GHfW8
- 11thEarlOfMar 11y ago
  Nice!

unwind 11y ago

Looks fantastic, and was seriously fun to fiddle a bit with. One bug though: you can't back out from the site, the history is flooded with geargenerator.com addresses. Had to close the tab (Firefox 40.0.3 on Windows).

dspillett 11y ago
> the history is flooded with geargenerator.com addresses I'm seeing this a lot in apps these days. In many places I think it is intentional: where the entire state of the current view can be encoded in the URL it effectively gives you a "free" undo feature and can be quite useful (like when I'm playing with potential new running routes in Google maps).
- peterclary 11y ago
  Yes, and that can be useful. However, if you use the back button to return to a previous URL it doesn't appear to update the settings from the URL. This means you can't use the back button as an Undo button.
  - degenerate 11y ago
    Agree - I'd much prefer an "undo/redo" button inside the app, instead of flooding my history state. They can change the URL all they want (for linkability) but leave my damn history alone!

osullivj 11y ago

Very cool! The guys at http://romaxtech.com http://romaxtech.com should take a look at this...

amelius 11y ago

One thing I'm wondering about: do opposing gears always need to have the same form for the teeth? Also, what are the constraints that lead to the form of the teeth? I can imagine that one constraint is that the teeth must "roll" onto each other. But are there more constraints?

fnordfnordfnord 11y ago
The "rounded" design allows constant contact to be maintained between two gears. If they were of the simpler design with flat faces on the teeth, they would simply wear to this shape anyway, but in the process they would also end up with slack between them. A helical twist is also usually employed which improves the transition between adjacent teeth, and consequently reduces noise. Ever hear a transmission with a loud whine in reverse gear? IIRC, it's because they didn't use the helical twist trick on the reverse gear. I have no idea why they wouldn't though. If we're lucky, an ME will be along in a bit and explain all of this for us much better.
- Asbostos 11y ago
  Yep. Straight cut gears are cheaper to make. Since people don't do as much reversing as going forward, it's probably a good compromise on cost vs comfort.
  - fnordfnordfnord 11y ago
    Makes sense to me.
msandford 11y ago
Opposing gears don't have the same form unless they have the same number of teeth. This isn't obvious when you look at the first gear pair, but look at the pair doing the 10:1 reduction. The teeth of the small gear are undercut quite a bit while the teeth on the big gear aren't undercut at all. The only real constraint is that the teeth must roll into one another as you concluded.
IshKebab 11y ago

peterclary 11y ago

This is amazing! Well done and thank you!

KaiserPro 11y ago

This is majestic. I've been battling with making my own gears in Modo for a while (the inbuilt primitive scales the teeth size as well as number of teeth) However this allows me to create ratios AND test them at the same time. This is invaluable. When I get time I shall be using this for my laser cuttings.

phkahler 11y ago

Is that correct? The tip of the gear tooth seems to rub up against the other as it approaches. Shouldn't there be a small clearance there? or is there? Also, is there a way to export to a format that can be loaded into SolveSpace?

Asbostos 11y ago
Any clearance there would result in backlash. I suppose you need some to allow for manufacturing tolerance though.
- phkahler 11y ago
  That's fine, but when I first looked at it, it seemed like they were sliding. Now I see that it may be rolling as desired.

fnordfnordfnord 11y ago

Neat. Now I want to be able to give the gears mass, and configure the "engine's" power output; and or maybe helical gear teeth.

jonjenk 11y ago

I've created a lot of 3D printed gears over the last few years and one of the best tools I've found is from Rainer Hessmer. http://hessmer.org/gears/InvoluteSpurGearBuilder.html http://hessmer.org/gears/InvoluteSpurGearBuilder.html It allows you to specify additional parameters like backlash, clearance, and profile shift. It also allows you to output in DXF which tends to be more of a standard in the engineering world.

oldpond 11y ago

Very nice.

crome 11y ago

Here s a referral link you can use to get 100$ off, im super stoked on this!! :) http://glowforge.com/referred/?kid=kmrbvD http://glowforge.com/referred/?kid=kmrbvD