I Milled!

[mike837go]

I did my first practice milling with my new G0516.

A piece of scrap-for-reuse, poorly clamped and a random (5/16") milling bit.

Still got a fairly straight cut across the steel.

Now I'm ready to build me another lathe. From scratch

 

[T Bredehoft]

That's what it's all about. The learning curve comes in when you "engineer" your project.

 

[mike837go]

I was being just a bit facetious. Make my own lathe? I don't have a foundry to pour the castings.... Yet.

My first official milling project is to make a copy of the output shaft of the belly mower's "transmission". It uses the rear PTO. Two shafts, a tensioner and triple-ganged belts moves the power down 14", 3" to the left and sends it forward.

The copy won't have the reduced diameter from where a previous owner neglected a bearing.

 

[brino]

Congrats on the first cuts!

Do be careful about poor clamping, don't damage you or the equipment.

Maybe a set of t-nuts and clamps is a good first project

-brino

 

[mike837go]

The machine came with 2 t-nuts. I put exhaust system studs in 'em and lined them up with holes in the "work piece" and torqued the nuts to about 20ftlbs with a wrench. There was very little chance things would get loose suddenly.

The 'poorly' side of things was that the holes I used were 6" from where I chose to mill. The 3/8" thick piece of scrap flexed away from the cutter. Passes back cut more material as the piece sprung back.

When I was trained on The Drill Press (middle and high school shop classes) proper clamping was REQUIRED. A stalled motor beats bashed hands or spinning work ANY day!

My first real project is building a replacement shaft for the transmission that gets the rear PTO power headed forward to a belly mower.

The vice that was included with the lathe/mill came with 2 more t-nuts. It has been mounted solidly and trued-up. Just waiting for the 1" round stock to show up.

All work will be done within the width of the vice's jaws. Any flexing will be within the compression of the bar and the oil between the cross slide, the carriage and the bed. Lets not forget about the flex in bed casting/mill support as well.

Daham. I used to think of machinery as solid objects with some moveable parts. This thinking of a conglomeration of near perfect pieces slipping, sliding, compressing, springing back, .000000000001" backlash is hurting my head!

 

[Ulma Doctor]

machining gets a little easier every time you do it.
it seems like a lot of stuff to keep track of, but as you do it, things will all become second nature with some practice and study.
i wish for your continued success!

 

[mike837go]

Second attempt at milling last night.

Success!

After pulling the bit back out of the collet. Seems you have to REALLY tighten the (need the proper name for the internally threaded piece that secures the collet in the spindle).

I made the shaft my finish mower needs.

Image

• mike837go
• Aug 12, 2015

PTO box output shaft

Now to wait for Tractor Supply to get the new belts...

 

[tmarks11]

After pulling the bit back out of the collet. Seems you have to REALLY tighten the (need the proper name for the internally threaded piece that secures the collet in the spindle).

Drawbar.

Typically should be 25-30 ft lbs of torque to tighten the drawbar.

 

[T Bredehoft]

I've started accumulating R8 tool holders, they use a setscrew to secure the end mill, don't require over torquing the drawbar.

 

[tmarks11]

I am a big fan of endmill holders. Just make sure the endmills you are buying have weldon flats. Many will argue you don't need them, but no reason not to get them if you rely on end mill holders.