Alloy or steel

[wesley]

Am about to start cutting my gears for the rudys tractor,now l have enough brass to do all the gears apart from the two bigger bull gears and with the price of brasstock being as it is ,could l get away with making the bull gears out of ally or steel as l have this in stock,my thinking is that the tractor will not be run hour after hour so was hoping that all0y would do ,plus its lighter but do not mind using steel advice would be great please.
wes

 

[Chiptosser]

Ether will work just fine. If you are asking about aluminum and steels.

Are you referring to Aluminium, when you say alloy?

Alloy is a description of different elements used in a material.
What alloy of steel, what alloy of aluminum ect.

 

[wesley]

Yes sorry l did mean aluminium ,have some 10mm sheet,so can them out of that as the gears are 1/8" face,thanks for that
wes

 

[Charles Lamont]

I'm not sure brass and light alloy will run together all that well. I'd prefer steel, personally.

 

[Chiptosser]

(A light Alloy)
What is a light alloy???
Again, If you are referring to Aluminum, there are many grades of aluminum.
Different grades of aluminum have different properties and different alloys are in the aluminum.
Many gears are made of aluminum, connecting rods are made of aluminum.
The gears run with steel and/or brass ect.

 

[Charles Lamont]

Yes, I meant aluminium alloy, and yes, there are lot of them, but so far it does not appear that Wesley knows what grade he is has, which was one reason for my suggesting steel would be better, even though there are all sorts of steels with widely differing properties and heat treatments too.

 

[Chiptosser]

Wesley, Can you give some information on the requirements for this gear?
Thanks

 

[tornitore45]

1/8" Face is pretty thin for an Aluminum gear. I would make 0ut of steel since is no very thick to cut.

 

[wesley]

Yes l did have a play today and when you start looking at 1/8" its thin ,so will make the to big bull gears that are 2 1/2" out of round steel bar stock,that way l can leave a boss on them so when l cut the gears have more to hold on to if you get my thinking then the other gears will make in brass,dam there a lot to learn and thanks for all your advice.
wes

 

[bobden72]

Am about to start cutting my gears for the rudys tractor,now l have enough brass to do all the gears apart from the two bigger bull gears and with the price of brasstock being as it is ,could l get away with making the bull gears out of ally or steel as l have this in stock,my thinking is that the tractor will not be run hour after hour so was hoping that all0y would do ,plus its lighter but do not mind using steel advice would be great please.
wes

Wesley I have just finished cutting my gears today for my tractor. I have made all my gears from cast iron and made them all .210" thick, the thickness was based on a commercial 48DP gear I had in my might be useful box. .125" seems rather narrow to me, I would think aluminium was not a good choice..

 

[bobden72]

Yes l did have a play today and when you start looking at 1/8" its thin ,so will make the to big bull gears that are 2 1/2" out of round steel bar stock,that way l can leave a boss on them so when l cut the gears have more to hold on to if you get my thinking then the other gears will make in brass,dam there a lot to learn and thanks for all your advice.
wes

Wesley you will need bigger than 2 1/2" diameter bar. 2 1/2" is the DP figure the actual gear blank for the 120 tooth bull gear needs to be 2.541 diam. All the gears diameter needs to be bigger than the PD figures quoted, which is a theoretical circle. To get the blank outer diameter use the formula N+2 divided by the DP, where N=number of teeth. If you do not the gears will not mesh.

 

[olympic]

Just a thought, Wesley: you don't need to buy a length of expensive brass bar stock if you can find a small square or rectangular piece of sheet brass to make round....

 

[mnay]

IMHO
This tractor will probably never be used to pull a plow, but just putt across the floor now and then. I would say aluminum would be fine, except for a small pinion gear.
Cut a couple of teeth and squeeze them with pliers and see how prone they are to bend or brake. If it is not cast aluminum I would use it.
Still in the end it is your call after all of our opinions.
Have fun. I have that project on my bucket list.

 

[Charles Lamont]

It is the wear rate more than the strength of an aluminium gear that concerns me.

 

[bobden72]

Wesley you will need bigger than 2 1/2" diameter bar. 2 1/2" is the DP figure the actual gear blank for the 120 tooth bull gear needs to be 2.541 diam. All the gears diameter needs to be bigger than the PD figures quoted, which is a theoretical circle. To get the blank outer diameter use the formula N+2 divided by the DP, where N=number of teeth. If you do not the gears will not mesh.

A few pictures of my Case, just fitted the gears I cut from cast iron. I am also fitting a flywheel clutch and Woolf valve gear to be more like a Case. A dummy heat exchanged will also be fitted along with a water pump. As for the cylinder I am going to fit a cylindrical crosshead guide again like the full size Case.

 

[Chiptosser]

.125 is a bit narrow, Aluminum 7075 is a great candidate for you application.
As was mentioned, a wider face would be a good idea.

 

[wesley]

Dam fine work bobden,and thanks for your help,you all have been very kind with the advice, so its going to be steel gears but thicker as well,will give update and will try to send some pictures.
wes