# 3D printed gear



## cobbadog (Nov 3, 2018)

G'Day everyone, a new guy here form NSW Australia. I am interested in your views on the making of a small gear/s using a 3D printer. I have NO experience in this field but what I am after is a set of up to 3 gears and no larger than 25mm with a selected amount of teeth to suit a 3mm pitch lead screw on my 14th hand Chinese lathe for a thread chasing dial to help me with making some common metric threads.
I am open for any ideas and thoughts and even offers of help. 
Thanks in advance,
Cobbadog


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## cox24711 (Nov 4, 2018)

Hello Cobbadog welcome to the forum, 
Sorry I don't have much experience with 3D printers I have only used the one at school handful of times, and what I can tell you is that they are a pain and I don't think they would last very long at all when meshing with a lead screw.
but here is a link to where I get my metal gears for my projects,
https://www.ebay.com/str/worldwindow2010/
 They are extremely cheap compared to boston gears. but they are surprisingly good quality, made out of good steel or aluminium, (the steel ones are even hardened) and they will almost certainly have what you are looking for.

I hope this is some help to you
Greg


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## lohring (Nov 4, 2018)

Here's a test of a change gear on an Atlas lathe.  It looks promising and would probably be even better with a different material than PLA.
Lohring Miller


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## lohring (Nov 4, 2018)

PS  That looks like a great source for gears, bearings, and similar parts.  Is the quality reasonable?

Lohring Miller


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## cobbadog (Nov 4, 2018)

Hi Guys and thanks for the replies. I had already watched tublacains' video and is why I asked about 3D printing a couple of gears. After his experiment and the particular type of product he used in the printing you would have to prefer a solid gear over one that is not solid. Another YouTube clip showed a drive gear for a RC car and it worked out to be a success under the short testing he did. As I absolutely know nothing about 3D printing I have since learnt that different properties of material can be sprayed and even a type of nylon is also doable. 
Greg I looked at that site and I was amazes at what they do make and the pricing is great but there is one small problem. For an unknown reason he will not ship to Australia, maybe was refused entry at some stage!
Quality of these gears would not be an issue for me as the pressure of the drive against the lead screw is very minimal. There is no resistance at all just a 2mm shaft slowly rotating in a metal block and a drop of oil every now and then.


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## Cogsy (Nov 4, 2018)

One trick I have found recently with PLA filament is a 1 hour soak in the oven at about 80 C 'anneals' the printed part and gives much higher mechanical strength and temperature resistance. I have a part taking relatively high force inside my dishwasher and PLA just wasn't working until I tried this process. If your gear is lightly loaded it will probably work fine, and would be very quick and cheap to make. Give it a go. If you don't have a printer, as long as you come up with a file to print I could do it for you and post it over.
Alternatively, you can always make yourself a simple 'hob' and cut the gears out of metal, provided you have a means of indexing and a mill to spin the cutter.


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## cobbadog (Nov 5, 2018)

Hi Cogsy,
Thanks for the added info and offer to make. I dont have a 3D printer nor a program to do so but with a tip I was given on another site there are companies maybe local if not but in China that mass produce metal and printed gears so I need to continue my search for exactly what size cogs I need then a supplier.
It was very kind of you to offer, thanks.
Cheers cobbadog


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## dkwflight (Nov 5, 2018)

Hi
Perhaps
some one could run off a 3D gear for you in AU?
What gears are you looking for?
Dennis


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## dkwflight (Nov 5, 2018)

Little machine shop gear set.  LMS ids in the US.
https://littlemachineshop.com/products/product_view.php?ProductID=1523&category=
Amadeal in the UK sels a version of the mini lathe
Warco also


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## lemelman (Nov 5, 2018)

A friend broke a gear in a shredding machine - it was a case of either a new machine or create a 3D model of the required special gear and 3D print it. The gear was printed in PLA and worked fine, and is still going strong.
My machine will print Nylon, but I havn't tried it yet. PLA is remarkably strong.


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## tjwal (Nov 5, 2018)

A 3D printed gear will work fine on a thread chasing dial.  I printed this one. https://www.thingiverse.com/thing:1306037  The teeth aren’t perfect but it works fine.

On a side note a Mod 1 gear meshes reasonably well with my 8tpi leadscrew so it will likely work with your 3mm one.


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## XD351 (Nov 5, 2018)

Try this place 
www.smallparts.com.au/store
I have purchase from them without any issues , just type in gears in their search engine .


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## Cogsy (Nov 5, 2018)

cobbadog said:


> Hi Cogsy,
> Thanks for the added info and offer to make. I dont have a 3D printer nor a program to do so but with a tip I was given on another site there are companies maybe local if not but in China that mass produce metal and printed gears so I need to continue my search for exactly what size cogs I need then a supplier.
> It was very kind of you to offer, thanks.
> Cheers cobbadog


According to tjwal's post, the gear he used should fit your leadscrew, and the design is already published. If you like I could print up a couple tonight and chuck them in the post.


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## XD351 (Nov 5, 2018)

Ok i had a little play today and checked the leadscrew  on my hafco al320 lathe and a 3mm pitch thread gauge fitted perfectly , i then had a dig through my collection of gears but only had a small pinion gear that matched . I had recently pegged a box of plastic gears in the bin but i think most of them would be too fine pitch anyway but left me thinking what on earth actually managed to get me to part with them - a mystery to solve ! Anyhow as i was walking out to lock up the shed i thought i would check my C2  sieg clone and strangely enough the change gears fit the leadscrew of the AL320 perfectly ! My sieg clone has the metal gear kit and i thought i could give you one of the plastic gears it came with but guess where they went ? Thats right out the door with the other plastic gears [emoji24]
So you could try :
Hare and forbes to see if they have any old stock from when they sold sieg lathes . Or the thread dial unit off an AL320g , i did look for this and their spare parts listing says call them .
Ausee , they sell sieg lathes and have them in plastic as single units - price ranges from around $5 up to around $15 or so ( the metal ones usually come as a set ) .
Try Ebay .
Or maybe someone has uploaded a file to thingiverse for the C2 lathe change gears.


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## tjwal (Nov 6, 2018)

Cogsy 
The gear I printed was for an 8 tpi  leadscrew.  This is a bit coarser than 3mm so the gear might not work. 
If I remember correctly for an 8tpi screw the DP of the gear is 26.x. A Mod1 gear works out to a DP of 25.4, which is close enough to work,
 And will be a better fit for a 3mm pitch screw.  The pressure angle of Mod1 change gears will be 20 degrees which isn’t a perfect fit (should be 14.5) but for a thread dial it’s not an issue.

Cheers
John


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## cobbadog (Nov 6, 2018)

WOW guys, so much help and I dont know how to thank you enough. This is the dial I purchased locally and when it got here the pinion gear is so fine I thought that it would not engage with a 3mm pitch lead screw. It was sold to suit a Sieg C2 and C3 so it just might engage but I cant try it out until later today to see if it will engage. My next problem that I am working on is what size gear and how many teeth I need on them to do the common metric threads. The numbers that keep popping up are 28, 30 and 32. That is a very kind gesture to print out a couple of gears but I do not want to waste your time and product if it is not suitable, also at the same time I would want to cover the costs of this along with postage.  I will also research hare n forbes and small engine parts for suitable gears but I need to confirm the gear sizes.
Once again I thank you all for your input and helpful advise.
Cobba
P.S. Is there a way to private message members here?


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## Cogsy (Nov 6, 2018)

You can private message, simply click on a members' name and a pop-up will appear. Click on the option 'Start a conversation'. That will open a text box to type in, then hit the 'Start a conversation' button at the bottom of the text box and it will send. When you receive a message it will show in the top right corner of any page (the little envelope icon will have a number next to it).


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## cobbadog (Nov 6, 2018)

Cheers Mate, you have been very helpful.


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## cox24711 (Nov 7, 2018)

cobbadog, he does ship to Australia you just got to ask him to
that's what I did when I bought my gears from him.


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## bmac2 (Nov 7, 2018)

Hi guys. I don’t have a 3D printer but thought I should chime in and mention that there is a Gear Extension for Inkscape.

https://www.wikihow.com/Draw-Gears-in-Inkscape


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## cobbadog (Nov 7, 2018)

Again a big thanks for the hints and tips to tracking down the gear/s I'm after. I will chase it up later today as work is now screaming at me.


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## CFLBob (Nov 8, 2018)

Maybe this is late, but has anyone tried 3D printing a gear in plastic (PLA or whatever your printer works with) and then investment casting it?  

I'm thinking maybe a low density print, not as strong as the material could be, invest it in the the kind of investment that jeweler's use and then casting the gear in brass or aluminum?  Not sure it would handle casting steel, but I think there is such as thing as investment casting steel. 

I don't know anything about this kind of investment, just that the seller is one the biggest names in the jewelry industry and is reputable.  Offered in case no one knows what I'm talking about.


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## lohring (Nov 9, 2018)

There are three filaments that I know of for 3D printed patterns for lost wax casting.
Polycast, Moldlay, and Machinable wax.  Polycast seems to be available only for industrial users.  Moldlay seems to be easier to use than Machinable wax.  I haven't tried any of them since my investment casting equipment isn't set up.  

Lohring Miller


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## CFLBob (Nov 9, 2018)

lohring said:


> There are three filaments that I know of for 3D printed patterns for lost wax casting.
> Polycast, Moldlay, and Machinable wax.  Polycast seems to be available only for industrial users.  Moldlay seems to be easier to use than Machinable wax.  I haven't tried any of them since my investment casting equipment isn't set up.
> 
> Lohring Miller



Thanks for those links!  Very cool.  

I don't have a 3D printer.  Yet.  It's seems like a natural for making parts by casting and casting is a very common manufacturing technique.   I'll copy those three links and keep them.


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## cobbadog (Nov 10, 2018)

I am hopeful I have found a supplier of gears "off the shelf" and I now only need to confirm the number of teeth, the pitch which they must match and a bore size already in steel. I am also very confident that one printed in this PLA product would also be a successful gear to use under the condition of which it will be put,  a simple rotating gear against a lead screw with no or very little resistance. 
Cobba


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## cobbadog (Dec 17, 2018)

Firstly I would like to thank everyone who has made suggestions and offers of help to get my thread chasing dial up and going. In my last post I found and bought some gears to do the job I needed. There are 3 different size gears from 10 teeth through to 14 teeth which covers the main metric threads I need to make. Once they arrived I made the body, pivot and dial up on the lathe and assembled it and gave it a run. All the time trying to think of ways to mark up the dial so that it can be read. Fortunately I made 2 dials as this one is a bit rough in the marking up department but I can still take a skim off the top and re mark it in a better way which is something I will do once I get over the normal pre Christmas rush.
I would also like to take this opportunity to wish everyone a Very Merry Christmas and a very Happy and Prosperous New Year.


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