I need two tiny gears

[Mjolinor]

I am sure that someone would cut those gears for you on a laser cutter. You are talking maybe 25 seconds cutting time and about 10 cents worth of plastic. You need to find a laser cutter forum or a makerspace that has one, there are thousands, these laser cutters are only a few hundred dollars now, cheaper than 3d printers.

[Tonyj]

You guys are great on your support here. Did not know I was going to do all this talking about this in just one day. Wow!

The cost comes in on the designing of your product into the computer for the laser or 3D printer to make. But you would think most people would already have some kind of gear design to work off of to save me some money. Yeah, it should not cost much at all for the material to make this at this tiny size.

Tony

[Mjolinor]

You could easily design what you want yourself.

Download openscad (preferred) or freecad (second choice) and install the gear plugins that people have written and that is all you need. You will feel a lot better about it having done it yourself too.

[curious aardvark]

yeah yeah - I'll have a go, and no I live in the uk.

But I like a challenge :-)

But you really need to start thinking in measurements. I mean: how thick - your answer: 'thin'.
lol that doesn't really help.

I can print from 0.1mm on up. parts that are 2mm thick are actually surprisingly strong.
I can also print - for something that small - in carbon fibre reinforced nylon. Not sure if it would be rigid enough, but by god it'd take a long time to wear it out :-)

I'll go look at the pics next to a proper rule ;-)

So I make those wheels about 6mm in diameter - but I still can't see any gear teeth ?

[Tonyj]

Curious aardvark, thank you for taking this on. But I did not know you were from UK. I was hoping to find some one here in the USA for I do not have to mess with shipping over seas. Is this forum from UK? I search USA 3D printing forum and this one came up first.

You did bring up a good point about getting the right measurements for people know what they have to put together, than trying to figure it out in that picture. I was thinking about making two circles with my word program that would be the right over all size of the two gears. In other words, print out paper gears that are the sizes I need made up. Then let people know what I need done.

I have already emailed some people for help. But I have yet heard back from them.

I like your effort you are putting in to this for me, but I rather work with someone in the usa, because I am going to need more gears if these two gears work first. That would be to much shipping over seas.

Thanks thou!
Tony

[Tonyj]

Hey Curious aardvark, this just pop in my head. Did you plan on just making the FILE of the gears I need for me to help me out? If so, then there would be no shipping. Then I can give that file to a person in USA to print out, if their printer is good enough.


Thanks,
Tony

[Tonyj]

Mjolinor, a laser cutting service just got back with me about my gears. They also said it would be a good idea for me to design my own gears and then give them the file to laser cut the gears. They said the minimum order is $25.00 that would give me a patch of gears made up for me, if I have a design already made up for them.

They said "geargenerator.com" could be a good place to start to build your own gear design. I have yet been there. I am going to it after I post this reply.

Bad news is that they said they are not sure how well they will come out at this tiny size. I still have yet had some one straight out tell me that they CAN 3D print or laser cut any thing this small. Hmm..

I would hate to pay $25.00 for something that will not work. I will keep looking I guess.

I want to thank you two for all your advice you been giving me. Means a LOT! I will get these gears made up some day.

Thanks,
Tony

[Mjolinor]

This is a good example of how finely you can cut with a laser cutter.

http://imgur.com/a/MUNUB

The main part of the tower is made from 8 flat panels, each diagonal brace is 0.5 mm thick.

[curious aardvark]

. I still have yet had some one straight out tell me that they CAN 3D print or laser cut any thing this small. Hmm..

maybe because you've yet to actually tell anyone exactly what size you need :-)
The problem is at your end - not anyone elses.

were you to say something like: 'I need gears with 6 teeth, 6mm diameter and 2 mm thick with a 1mm hole through the middle.
Then I suspect you'd get a lot more replies :-)

This is an international forum, people here from all over the world :-)

Okay as I'm a nice guy here's a quick openscad script I just done that makes gears.

// CA's mini gears
$fn=100;

nt=8; // number of teeth
tt=1.2; // width of gear teeth
lt=1.5; // length of gear teeth
gd=6; // overall gear diameter
gt=1; // gear thickness
ch=1; // centre hole size
ns=100; // sides in central hole - 6 for hex fitting, 100 for round

difference() {
cylinder(d=gd-lt*1.5,h=gt);
cylinder(d=ch,h=gt,$fn=ns);
} // end diff

difference() {
for(r=[1:nt]) {
rotate([0,0,(360/nt)*r]) translate([0,lt,gt/2]) cube([tt,lt,gt],center=true);
}
cylinder(d=ch,h=gt,$fn=ns);
} // end difference

Copy and paste everything in the quote window into openscad and press f5 to see a quick render and f6 to render for export. Can be exported as .stl, off, amf, dxg etc
All numbers are in millimetres.

Changing the numbers at the top changes exactly what it says to the right of the number :-)

Picture of gear with settings currently in script:

small gear.jpg

Work out what size gear you want. Find out what format the laser cutter people or whoever want it in. generate it, export it and viola - job done.
It might need tweaking, let me know if a particular set of numbers does something weird.
I tend to wing the maths and just fettle till it does what i want it to, by which time I generally have no idea how I got there :-)

And just for a laugh, when my current print is done I'll try and see just how small a gear I can print :-)

[Tonyj]

Curious aardvark, what I said was not for this forum. It was for the other people that already got with me about it before I came here. They already had a good idea how small this gear was going to be with out me giving them a design. Then I just got that Laser guy saying that they are not sure how it will come out. To me it seems like they should know what their machine can or can not do. That is all I was trying to say.

It is all good my friend. But I fully understand having a design for them will for sure point them in the right direction. With that said, thank you for putting this together for me. I will take a look at it.

Yeah, take a picture of that gear you print out and share it with us on here. I would like to see it.

Mjolinor, that is a cool looking tower made by a Laser cutter. Wow!

Thanks,
Tony