Brass Or Bronze (or Aluminium) For Gears

[MozamPete]

I want to machine up a couple of extra change gears for my lathe to get some extra thread pitches. I will be using a involute cutter to form the teeth and as this will be my first go at cutting gears I want to make them out of something softer than the original cast iron gears - so any wear caused by mismatch should be on my new gears and not risk damaging the original ones.

I'm thinking Aluminium may be too soft so was considering brass or bronze (I will have to buy the material anyway as I don't have anything large enough already at hand).

Any suggestions as to which would be more suitable/easier to use for a first time gear maker - a quick web search and some reference seem to recommend bronze for gears others brass.

Main concern is I don't want to risk damaging any of the original gears.

 

[Sandro]

I'd suggest aluminum. Modern aluminum alloys are fairly tough so should stand up well.

One thing though. You mention using something soft so as not to wear the original gears in case of mismatch. It's not really that much of a concern since if you don't get the gears right, they won't mess properly or even at all. You will need the right cutter profile for the gears you want to cut or the new gears won't be usable.

Hope that helps.

Sent from my D5106 using Tapatalk

 

[savarin]

I made a gear from a bit of home cast aluminium, pretty soft stuff.
It was also my first attempt at a gear.
Its still going strong after 2 years in my reverse tumbler even though it wasnt perfect and it gets lots of work.

 

[chips&more]

The typical use of said gears in a HM environment is minimal. I would make them out of phenolic…Dave.

 

[juiceclone]

Yeah, aluminum works well. I had to make all the imperial gears for my Sumore lathe, and they show no worry wear at all. Two years now.

 

[Ebel440]

If agree with making them from phenolic or Anything like Delrin nylon even polycarbonate. It'll be easier to make and last long enough. The cheap lathes come with all plastic gears and it works

 

[MozamPete]

Thanks for all the replies - sound like I'm underestimating aluminium (and plastic).
I already have some aluminium bar stock that would be large enough for most of the gear sizes I was considering making so I'll go with that when my cutter arrives.

 

[Karl_T]

...
I already have some aluminium bar stock that would be large enough for most of the gear sizes I was considering making so I'll go with that when my cutter arrives.

Ah, the most important rule. Use what you got.

Karl

 

[john.oliver35]

FYI tubalcain published some excellent videos on gear cutting in the home shop on Youtube a few months back. Search for 'Tubalcain gear cutting' on youtube.

 

[kwoodhands]

I want to machine up a couple of extra change gears for my lathe to get some extra thread pitches. I will be using a involute cutter to form the teeth and as this will be my first go at cutting gears I want to make them out of something softer than the original cast iron gears - so any wear caused by mismatch should be on my new gears and not risk damaging the original ones.

I'm thinking Aluminium may be too soft so was considering brass or bronze (I will have to buy the material anyway as I don't have anything large enough already at hand).

Any suggestions as to which would be more suitable/easier to use for a first time gear maker - a quick web search and some reference seem to recommend bronze for gears others brass.

Main concern is I don't want to risk damaging any of the original gears.

I haven't made a lot of gears but most were made from Acetal.I made several gears from Acetal thinking if I get it right I'll then make them in a harder material.The gears have held up well so far,about two years.
mike