[niki]

Good day

I have a cheap DP and when I want to change the table height I have to unlock the table and while turning it left/right pull it up or push it down.

I have no problems till I want to drill a large hole over small hole or vice-versa. In this case you must maintain the table at the same position.

But, if one drill is long and the other is short, you must re-adjust the table height and it is very difficult to return to the same position so the large hole will be drilled at the center of the small hole or, the small hole over the large hole center.

Regards
niki

 

[niki]

 

[ajh359]

I would drill the large hole and drill the small because you will have a pilot hole there. Use a short bit so that you do not have move your table.

 

[Ohio Ron]

You are wanting to drill a large hole over a small hole, why don't you just glue a dowel/plug in the hole and redrill? Maybe I missed something, but it seems like you went a long way to drill one hole over another.

I like your ingenuity and engineering skills, not to mention your photography and computer savy.

 

[niki]

Ohio Ron
Thank you for your kind words

OK, so here is the story....

I'm pre-cutting wheels in a few diameters to be used as knobs for jigs.

I cut them with Hole Saw that leaves the 1/4" hole at the center. I don't use them immediately but only when I need them for a jig.

But, I don't know which T-nut or bolt size I will be using...sometimes it's 1/4", sometimes 5/16" or 3/8".

When it comes to actual, sometimes I have to enlarge the 1/4" hole to 5/16", 3/8" or other for the T-Nut to go in and I have to drill a larger hole...not all the way but, just for the T-nut to sink in.

So, I'm talking about a situation that the small hole is already drilled and I want to drill Larger hole all the way and even more larger hole half way...and I still want them both at the center...so, I have to change drills from the 1/4", that is used to locate the center and clamp the wheel to the DP table...

After the wheel is clamped to the table, I have to change to larger dia drill that is usually also longer drill bit and I must move the DP table down (or up) but still come back and lock it at the same point.

Regards
niki

 

[Ohio Ron]

Make a lot of sense now, thanks

 

[ajh359]

Make a lot of sense now, thanks

Yes I understand now what you are doing now. Get you a small machinist vice and make you a 1/4" line up pin.

 

[niki]

Thank you

Ajh359
I have machinist vice (came with the DP) but I don't like to use it. Instead, I'm using different method like on this pic (from other post that I'll post soon)

Happy New Year
niki

 

[ajh359]

I guest it makes no difference as long you can center it. Being a X mechanical engineer for so long, I have did a lot of making parts for some of the projects of prototypes. You have to make your own parts and this kind of vise a lot.

 

[niki]

You are correct, as long as you achieve your goal, the method is not so important.

I think that you (I mean, Americans) are saying "there are many ways to strip a cat".....that's way we have so many jigs to perform the same task