Pulley ratios vs. the Real World

[hman]

DiscoDan - Looks like Jack is using a Weldon type adapter to hold the tools inside the spindle. So he's avoiding the main problem with using a DP for milling (the poor side load capability of Morse and Jacobs tapers).

Jack - I get this crazy vision of your substituting an air-over-oil jack for your manual one, thus having a Z power feed
(Told you it was crazy!)

Substituting the XY vise for the table does make sense, especially if that's what you know what you'll be using most of the time. Plus, you can always go back and forth as needed - might have to re-level, but the same shim set would probably work for both. And of course, you're now a member of the "round column mill club" (as I am), and get to experience the joys and wonders of having to re-establish 0,0 every time you raise or lower the head. Every machine tool has its quirks and trade-offs. Looks like you're doing pretty well at very low cost.

 

[jschmidling]

Jack, I assume if you found the video of that guy using a DP as a mill you also found the dozens of others that say why it is also a bad idea.

Sure. Don't remember who said it but this seems to fit: "The people who say it can't be done, need to get out of the way of the people who can do it.

Lot's of compromises but like I say about my mini-lathe, it's infinitely better than no lathe.

> I am curious how he hold his tool holder attached to the DP.

Yo no comprendo.

Jack

 

[jschmidling]

DiscoDan - Looks like Jack is using a Weldon type adapter to hold the tools inside the spindle. So he's avoiding the main problem with using a DP for milling (the poor side load capability of Morse and Jacobs tapers).

You guys are over my head. Weldon adapter is not part of my vocabulary and I got tired of looking for a definition.

Does it have anything to do with the flat I see on some end mills?

I am just chucking the tools into the chuck you see which I assume is the one it came with.

No problems with chuck falling out so far and I just assume it's been there so long that it wants to stay there.

I am concerned with the side loading of the bearings but don't know any simple way of dealing with that. Is this possibly one I missed?

I assume the chatter that starts when I push it too hard is caused by bearing play and this is really the limiting factor in the setup.

Jack

 

[hman]

Yes. The flats on end mils are called "Weldun flats" and are used to secure the end mills within end mill holders.

MT3-3/4" End Mill Holder,"A" Style - with Tang End: Abrasive Accessories: Amazon.com: Industrial & Scientific

MT3-3/4" End Mill Holder,"A" Style - with Tang End: Abrasive Accessories: Amazon.com: Industrial & Scientific

www.amazon.com

HHIP 3900-0107 R8 End Mill Holder, 1": Amazon.com: Industrial & Scientific

HHIP 3900-0107 R8 End Mill Holder, 1": Amazon.com: Industrial & Scientific

www.amazon.com

R-8 End Mill Holder, 5 pc. Set - Grizzly Industrial

Hold various sized end mills in your R-8 spindle with this End Mill Holder Set. Includes holders for 3/16", 3/8", 1/2", 5/8", and 3/4" end mills. Takes 7/16"-20 drawbar.

www.grizzly.com

I assumed you were doing something like this when I watched your video and saw the screw head sticking out of your spindle. Then I saw you re-installing the chuck later on. Apologies if I've misinterpreted what (I thought) I saw

 

[jschmidling]

I assumed you were doing something like this when I watched your video and saw the screw head sticking out of your spindle. Then I saw you re-installing the chuck later on. Apologies if I've misinterpreted what (I thought) I saw

I believe I caused the confusion by inserting that video link in the text. That is not my video. I just inserted it to give credit to the person who came with the bottle jack idea.

My setup is in the still pic that followed it. My previous setup was pictured up thread.

Sorry but now I know what a Weldon flat is.;

Thanks,

Jack

 

[rock_breaker]

In your photos, it looks like the shafts sre realatively close to each other which might cause slippage of the smaller pulley do to less belt contact area. If this is happening the smaller pulley will get hot. Another thought is whether or not the bottom of the belt is riding on the inner diameter of either pulleyagain slippage.
Have a good day
Ray

 

[jschmidling]

In your photos, it looks like the shafts sre realatively close to each other which might cause slippage of the smaller pulley do to less belt contact area. If this is happening the smaller pulley will get hot. Another thought is whether or not the bottom of the belt is riding on the inner diameter of either pulley again slippage.

Never thought of that last point but I forgot to mention (you can see in the latest pic) that I ditched the two belt mod and went back to the original config. It complicated moving the head up and down and there doesn't seem to be any pressing need for speeds less than 700 RPM.

It was fun working out the problem and if I go back to it, I will put the 3rd pulley much farther off the center line.

Thanks for your thoughts,

js

 

[jschmidling]

Does anyone know how to remove the drive pulley from this drill press? Photos up thread.

Seems like most of the chatter I hear sounds a lot like the same sound as I get when just moving the pulley up and down and might just need some sort of fiber washer/spaces but I can't figure out how to move the pulley beyond the up/down limits.

The manual explains how to adjust longitudinal slop but no clue in the drawings.

js

 

[jschmidling]

Here is another update on my drill to mill conversion and a couple of questions.

The run out of a drill rod in my mill/drill is about 12 mils and seems to be the cause of lots of problems milling with it.

Finally got the chuck off and find near zero runout on the spindle.

Two questions:

1. There is no clue on the taper of the chuck in the manual or the machine so, how do I determine what the taper is so that I can get a new chuck?

2. Is there any alternative to a Jacob's chuck for holding end mills in a drill press?

Here is a pic with the new X Y table. I changed my mind of the cross slide vice and really like this table and for $100, it's a real steal.




Jack

 

[MrWhoopee]

I'm impressed that your runout is only .012. Even more impressed that the chuck hasn't fallen out of the spindle. It must be seated in the taper quite firmly. If you succeed in removing it to try a different method of holding the cutter I suspect you will discover why everyone says that a morse taper is not suitable for this purpose.