compact reversed cim gearbox and output shaft question

[Chak]

Originally Posted by Aaron Ng

The one time me and Chak had to remove a roll pin, We spent a good ten minutes hammering it, then broke a drill bit.

After reading this thread, I now understand that trying to drill out the roll pin back then was a bad idea.

Has anyone ever tried to replace the vex ballshifter output in real life though?

[InFlight]

An Arbor press is the "correct tool" for the job. Applying controlled steadily increased pressure until the pin slides is far better than Hammering / Pounding the pin.

An Arbor press is also handy for removing mounting pins/collars from pneumatic actuators and setting bearings in slightly undersized holes.

A one ton arbor press can be found for under $100, it really one of those basic tools that any reasonably well equipped FRC shop should have.

A drill bit is too long for the job; it's subject to column buckling with high axial force (Euler formula). You can make a short pressing tool on your lathe for a specific job. When in a hurry I have found a steel bolt the correct sizes works well enough.

[asid61]

Originally Posted by InFlight

An Arbor press is the "correct tool" for the job. Applying controlled steadily increased pressure until the pin slides is far better than Hammering / Pounding the pin.

An Arbor press is also handy for removing mounting pins/collars from pneumatic actuators and setting bearings in slightly undersized holes.

A one ton arbor press can be found for under $100, it really one of those basic tools that any reasonably well equipped FRC shop should have.

A drill bit is too long for the job; it's subject to column buckling with high axial force (Euler formula). You can make a short pressing tool on your lathe for a specific job. When in a hurry I have found a steel bolt the correct sizes works well enough.

I believe he was trying to drill it out, not press it out with a drill bit.
I've seen videos of people hammering them out and in before, but if it's possible to press that sounds much easier than whacking at it.

[InFlight]

Originally Posted by asid61

I believe he was trying to drill it out, not press it out with a drill bit.
I've seen videos of people hammering them out and in before, but if it's possible to press that sounds much easier than whacking at it.

I believe most spring pins are hardened spring steel (something like 1080). While you can drill it with a HSS bit, it would be a slow process. A cobalt bit(M42) would be the best option, and still ugly. Drilling it out would definitely be my last choice of methods.

[Cothron Theiss]

Originally Posted by InFlight

A one ton arbor press can be found for under $100, it really one of those basic tools that any reasonably well equipped FRC shop should have.

Having just gone through a season where I tried to use lots of press-fit bearings without a press, I can attest to this. And now that I've found that an 8mm shaft makes a wonderful press-fit into a 5/16 bore, I'll be needing a press even more.

[asid61]

Originally Posted by Cothron Theiss

Having just gone through a season where I tried to use lots of press-fit bearings without a press, I can attest to this. And now that I've found that an 8mm shaft makes a wonderful press-fit into a 5/16 bore, I'll be needing a press even more.

I've had a lot of luck pressing things with just a large vise (we have nice wide ones in the woodshop) but there are times when a press comes in handy.

Getting one suitable for 1/2" hex broaches like a 5 ton might be wise.

[InFlight]

An arbor press is handy for handling small jobs.

A 1/2 hex broach is nearly a foot long, it really requires a full size press that has more travel. Most small presses seem to be at least 12 Ton. If you have the floor space for one, might as well go for at least a 20 ton as they are not much bigger.

[Cothron Theiss]

Originally Posted by asid61

Getting one suitable for 1/2" hex broaches like a 5 ton might be wise.

Originally Posted by InFlight

If you have the floor space for one, might as well go for at least a 20 ton as they are not much bigger.

I'll mention it to my team if they look at buying one, but since I've graduated, my 2 cents have become worthless. Oh well. I've got access to some large presses at work.