New and inexperienced

[Andy CarruthersParticipant @andycarruthers33275]

Hi All,

Another new joiner and this one without much experience – but every day is a school-day – right?

I have a Warco 180 and a 3 axis mini-mill to learn the ropes with, I'm also into 3D printing and dabble with electronics too

I'll be asking plenty of dumb questions – like this one:

I want to cut gears and am reading through Ivan Law's book – where can I purchase and arbor and involute cutters for small diameter (25mm max?) brass gears? my mill takes ER25 collets

[Andy CarruthersParticipant @andycarruthers33275]

[JasonBModerator @jasonb]

Welcome to the forum

You are best holding the gear cutters on a milling arbor, most of these will fit into the Morse or R8 spindle of your mill. You need to buy the right size for your particular cutter, Imperial DP ones will usually have a 1" bore but Metric MOD sizes quite often have a 22mm bore

[alan-lloydParticipant @alan-lloyd]

You can buy ready made brass gears from Meccano Spares, they advertise in ME

[not done it yetParticipant @notdoneityet]

Andy,

Possibly better to start with sourcing the cutters you need. The arbor will need to be sized appropriately. Straight shank arbors are available for fitting in collets, I suppose? I'm getting ready to make a pile of 16DP gears and I am determined these will be cut with a horizontal set up. I've made my 22mm arbor and spacers to suit the cutters I have sourced.

Some may ask why not do it with a vertical spindle, but the next job might well be dozens of ~1.25mm slots about 100mm long around a cylinder of about 120mm diameter (originals were all Impreial dims), so I reckon support at both ends of the arbor will be better.

So, how many teeth are you cutting on these gears and how small might they be? With all the details, someone may be able to give you precise info.

[JasonBModerator @jasonb]

On a mini mill you may start to run out of Z height if you stack up a collet chuck and plain shank arbor plust whatever height your rotarytable or dividing head needs. You will save room and have a more rigid setup with a stub arbor directly in the spindle taper

[Neil WyattModerator @neilwyatt]

Welcome Andy,

I've found a 'rack form cutter', which is easily turned from silver steel, works excellently for making small brass gears.

Some discussion HERE. (I must finish that project – being put off by making a 10" diameter gear!)

Neil

[Andy CarruthersParticipant @andycarruthers33275]

Gosh what a welcome and a wealth of information too!

Thanks all, and I'm encouraged by what I read and see already – much appreciated

As for gear sizing, I have a project in mind which will be Arduino / very small stepper motor driven (assuming the motor delivers enough torque) – I can't say too much as there is a commercial implication – but ~16 DP and up to 4" in diameter seems about right, I haven't absorbed Ivan's book yet

Meccano gears are a good thought too – thanks

@Neil – you are waaay ahead of where I want to get to!

[Andy CarruthersParticipant @andycarruthers33275]

I meant 4" circumference…. Duh!

[Andy CarruthersParticipant @andycarruthers33275]

@Neil – having seen your posts on 3D printing thread – is there any reason for making brass gears as opposed to 3D printing the same? If it's aesthetics, I "get it" as I'm sure brass looks much better than plastic

Just curious…

[Anonymous]

Posted by Andy Carruthers on 10/07/2017 13:51:13:

……… is there any reason for making brass gears as opposed to 3D printing the same?

Probably a question of accuracy versus resolution, plus it's a right royal PITA "deburring" the flash. Although of course it is perfectly possible to 3D print gears:

These are 10DP if I recall correctly.

Andrew

[john carruthersParticipant @johncarruthers46255]

Hello Andy, depending how many gears you need to produce, would a single fly cutter suit your needs?
I did some clock wheels in brass using one.
Also, what will you use for indexing?

[Andy CarruthersParticipant @andycarruthers33275]

Hi John – nice surname

I'm considering fly cutting or as per Neil's home made silver steel cutter for small brass gears though I do need to mount a vice on my lathe which isn't proving easy, and the CNC mill PC has just failed too – I think it's the motherboard

3D printing is another avenue but the item I want to make has telescopic tubing which has to be brass therefore it seems to me brass gears would be ideal as I can solder them on

Bear in mind I'm a *complete* novice at all this and on a steep learning curve, YouTube videos are very helpful though developing even basic skills is proving "interesting"

I will get a rotary table or indexing head with dividing plate at some point or have seen a home made protractor jig which will do the trick – whatever is the quickest route to success given my lack of competence

[Author]

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