Help with drill-Mill conversion

[irving2008]

Cheers, so I probably need a lock nut as well then? The original one just squeezed the inner race on to the step on the shaft.

The other problem is how to drill the hole in to the end of the quill for the chuck lock bolt. I foolishly thought it would fit in the lathe but that also has an M2 taper, Duh

Is it safe/accurate to hold a drill bit (facing up) in a vise and lower the quill down over it?

Safe - maybe if you can hold it tightly - drills have been used as lathes by holding the tooling in a vice and the workpiece in the chuck (I've done it).

Accuracy, its hard to see how you'd get the drill absolutely in-line with the quill. Here's an idea tho.
Acquire a block of MS say 50mm cubed. Drill an M4 tapping hole through the center of one face and tap M4. Put the cube in the vice with the M4 hole horizontal and accessible through the side of the vice jaws then drill down through the centre of the face with the drill you want to use to drill the quill. Remove the drill and without moving the vice put the drill shaft in the hole and lock in with a M4 bolt.

Remove the chuck and lower the quill onto the drill... careful with speeds and use coolant if poss.

You might need to grind a flat on the drill shaft to locate with the locking bolt.

The accuracy depends on how square the chuck was to the quill initially...

So, JohnS, Robin, BillTodd, etc (as real engineers) where's the flaw in my suggestion?

[BillTodd]

I wouldn't call myself an real engineer, or indeed, any kind of engineer but...

That sound like a good plan to me :)

Ross, What's the end of the quill look like? e.g. does it have a centre spot from the taper machining operation?

The accuracy depends on how square the chuck was to the quill initially...

Actually, your clever plan means the new drill 'chuck' will be properly aligned with the quill travel regardless of vice alignment.

[Ross77]

Sounds good to me :clap:, have to scavenge a block of steel, sounds quite big. Ive got Al that size but suppose its not ridged enough.

Hope to make a start at the weekend, so ordering last few parts

Just looking at the uniport from DIY CNC (from a thread on here) , looks to to be perfect for a mill, is it beter than the opto board?

[Ross77]

Bill
Didnt see your post as I was replying to the previous.

Ross, What's the end of the quill look like? e.g. does it have a centre spot from the taper machining operation?

Cant remember, I'll have a look tommorow, Is this an issue if there is a centre spot?

[BillTodd]

Is this an issue if there is a centre spot?

Just makes it easier :)

[irving2008]

Added thoughts...

Size of block = size of drill x 2-ish need enough metal for the locking bolt to remain rigid

If drill shaft < drill size (as it might be if its a big drill) then drill out the hole shaft sized first then use the proper drill to bore down 10-15mm to provide a locating seat... then remove drill etc as before....

Ally instead of MS... can't see why not, maybe go for a bit more 'meat' on it. Only issue might be getting a good lock on the drill... if you never want to use the drill again without some effort you could try loctite in the hole!

thanks for the +ve feedback

[Robin Hewitt]

So, JohnS, Robin, BillTodd, etc (as real engineers) where's the flaw in my suggestion?

Hang on, reality check.

Just how long is this drill bit?

Sounds like it has to reach up through the morse taper, past the taper knockout slot and then all the way up through the quill?

You reckon this pipe auger is going to start on centre without some kind of guide bushing :heehee:

[Ross77]

Uhmm. How do I say this.........

It dose fit in the lathe. I forgot the splined end was narrower than the 20mm shank at the taper. Just fits in far enough, about 25mm projecting from the chuck.

SORRY,SORRY, SORRY

Sounds like it has to reach up through the morse taper, past the taper knockout slot and then all the way up through the quill?

Not all the way through as this was the point, securing the collet chuck from the underneath, 90mm for the taper and knock out section + shank in chuck + depth of hole for new bolt thread. so long enough.

[Ross77]

Finally got some workshop time this evening and finished setting up the lathe. :dance:

Spent 30mins centering the quill in the 4 jaw chuck. What a nightmare!think Ive got it sorted now. (when I realised that 0.001" run out is F**k all) Ive drilled out the knockout slot to 10mm and created a start point for the tap drill.

The hole through the ER chuck is about 9mm , so the max bolt size I can use is M8, Problem is getting a drill bit and Tap that will reach the 150mm
required.......

Any one know of a source of long reach taps? or will i have to make up some sort of extension bar?

[irving2008]

Finally got some workshop time this evening and finished setting up the lathe. :dance:

Spent 30mins centering the quill in the 4 jaw chuck. What a nightmare!think Ive got it sorted now. (when I realised that 0.001" run out is F**k all) Ive drilled out the knockout slot to 10mm and created a start point for the tap drill.

The hole through the ER chuck is about 9mm , so the max bolt size I can use is M8, Problem is getting a drill bit and Tap that will reach the 150mm
required.......

Any one know of a source of long reach taps? or will i have to make up some sort of extension bar?

Let me get this right... you're drilling out the quill to allow a draw bar through to pull the ER collet chuck into the quill... so what are you planning to tap? did I miss something?