Micromouse Axle - Day 1

This job spins off from helping the student I spoke about in the previous post, which I helped him to enlarge a hole on the hub of a couple of gears.  The little modification on the off the shelf axle he bought doesn't fit well in his design.  So he asked if I can make him one according to his specs.  I always have problem with too small a part but the job seemed simple enough for me to play with.  So I took it on.  He sent me the drawings which I rearrange to get this:

I started wanting to turn down a piece of bigger diameter SS304 left over from the job I did for my dad.  But the amount of flex I get while turning it down to the required 4mm diameter made me gave up the idea.  The amount protruding out of the chuck (around 100mm) is simply to much.  The flex was mainly in the centre as I've the tailstock end of the rod in the revolving centre.

After some discussion with the good folks at Metalworkingfun.com, I decided to start off the job with 4mm SS rod instead.  The opportunity to buy the SS rod came when I was sending my car to the workshop (Toyota Recall Exercise for the drive shaft).  Bought a piece of 4mm dia SS rod of about 500mm length.  I asked if they can cut it into 80mm piece.  The lady looked me into the face and said, "We'll charge you SGD 5 per cut".  The rod cost SGD 10 before tax and since I've a bandsaw at home, I thank her for the offer and pick up the piece.

I didn't finish the job today as I realized after drilling the 2.1mm diameter hole that I don't have any tap smaller than M3... Lolz... So I turned down one end to the required 3mm dia for the fun of it.

Back home, I cut off a 75mm section and clean off the sawn end in the lathe.

The rest of the session will be boring to most; just the facing and turning stuff.  Hey! Like I said in my profile, I'm still a beginner!  Lolz...

Deburring with a larger drill.

This was when I realized I don't have any tap smaller than M3... But I continue on with the turning of the 3mm dia section to a length of 8mm.

I'm thinking, when getting the tap, would carbon steel tap work for stainless steel?  Or I should go for more the more expensive HSS tap?  This may be the only job that requires the small tap...

There will not be any update for about 2 weeks.  My wife and I will be going Israel with our Church.  I'm sure we'll have a great time there.  I'll continue working on this job when I get back, before going back to my day job on April 1st.

Meanwhile, be bless!