<scratch head> Ok so how do I align this properly???

[SPiN Racing]

Hello All

This has been bugging me for several weeks now.

Im making the peck drill as you all know.. and I had to mill a slot in the round chunk of stainless. I also drilled holes front and back to allow the shaft to slide, as well as the arbor to be threaded into it for the tailstock.

SO here is my problem.

I have a ROUND chunk of stainless. With a slot in it.

I need to drill a hole in the thing.. at a right angle to the slot, for the pivot.

SO what I did last time, if you look at the peck drill thread.. I put a shaft into the mill.. and moved it to the side to press against the side INSIDE the slot.. when I needed to re-slot it deeper.

It didnt work quite right... I was off in the bottom of the hole by 1/6 or so of an inch..... the thing was rotated a couple degrees I guess.


SO
here is a pic.


I need to go through the side of the slot.. and out the other side. And it has to be at a right angle.

Im ok on getting the depth right.. I have a edge finger wobble thing. ANd I can crank the mill the right distance to get the left right.
I can also edge find against the jaw of the vice.. so I can get the other axis correct.
Depth is simply a matter of going through it.

The problem is the rotation of the part.. it needs to be correct in the vice.

I would do something like the HEX cutter holder thing.. but then again.. how do you get the rotation of it correct?

<scratching head and frustrated as its just.. not.. quite.. there>

 


THanks!
Scott

[bogstandard]

Spin,

You have made a standard mistake, by not planning far enough ahead. Because you don't have a rotary table or a setting block like Bernd has made, you should have drilled the hole first, then put a bar thru and used your dti on the bar to get it level, then cut the slot.

But that is now in the past, lets see if we can get you back on the straight and narrow.

The only real datum you have to work to are the sides of the slot. So unless you have something that will clamp in the slot and leave a sticky out bit so you can measure it, this C-o-C (genuine UK version) will give you something to try to get you back on track.

The pic should give you a solution to try. A bit rough and ready, but I have used bits of wood at times myself to get me out of silly situations. Don't go wacking the wood in with a sledge, just put it in the vice and gently squeeze it into position until the parallel is locked where it needs to be. The angles on the wedge I have shown are for graphic pictures only, yours should be almost parallel. Once you have it all levelled up in the vice, and tightened up, a wiggle on the parallel should release it. Then measure up and drill your hole.

I hope this helps you out of your sticky situation.

Bogs

[SPiN Racing]

OH OH OH Excellent!!!

ANd since I followed advice and got a set of parallels two weeks ago... I CAN DO THIS NOW!!!  YAY!!!!

and thats sooo damn simple.. and effective!

THANK YOU!

ANd yeah I thought of that after the fact.. but not far enough to figure the bar through it to go level.. that is slick.. and I will remember it!


Ahh Ok so thats the plan then for me.


Its part of the challenge.. each thing we make is like a chess match..
Ok I need it to look like this... cut here and here.. wait.... how do I hold it for each cut.. and can I even get in there with a cutter???


Thanks John
Thats a excellent trick.. and if I can take some time at dinner tomorrow (I work 3 miles away) I might come home and give it a whirl.

[bogstandard]

Hope it works for you Spin.

Bogs

[Divided he ad]

Good stuff John 


I seem to remember doing it very differently..... But not as precise.... So I won't confuse the issue 





Hope it all works out Scott. (no reason why it shouldn't!)




Ralph.


Just noticed the pic' is the slot right through? .... Two parallel bars?  Anyway..... The boggie method will probably work better! 

[SPiN Racing]

Nope not through..

No not in bed yet either.. going in a few..

Yes.. gonna try the Bog method.. looks to be a winner

[rleete]

Alternate method:  If you centered the slot, the edges are the same height off center.  Clamp it in the vise sideways (slot horizontal) with a parallel over the slot, and that will square it up.

[Bernd]

Nice save John.

Before I even got to your answer I was thinking the same thing.

Funny how great minds think a like. 

Roger, Interesting way. Might work.

Bernd

[bogstandard]

There are lots of ways to do things, my way should work, but if it doesn't, there are a lot of different ones that can be tried.

There is most probably a very perfect technical way that uses thousands of bucks of equipment, but usually the cheapest and simplest ways get us to where we need to be.

The sky won't fall in if we are a few thou out, and there are no such things in our little world as accuracy police.


Bogs

[Mustang]

John & Roger

Nice tid-bits of info to file away for future use. Having a two cell brain has it's advantages when absorbing all the useful information that is published on this site. Only have to search in one or the other. 

Andy

[bogstandard]

I see,

Boasting that you've got more brain cells than me   


Bogs

[rleete]

Bogs, ust throwing out an alternate idea.  There's no doubt in my mind that your way is better - after all, if you want something perpendicular to the surface, it's best to use that surface to guage to.  Not sure if I would use the wedge idea, though.  Probably make a bit to fit in the slot tighter and indicate off that.

See, being a CAD guy (the real thing, not just C-o-C), I've kinda gotten used to 'seeing' things in 3D.  But, I've learned that most others don't have that particular skill handicap, so I thought I'd toss that out to get him to look at it another way.  Being the headcase that I am, I decided to model it.  Just being a little off center with the slot can throw the angle off quite a bit.  Of course, it depends on the diameter of the bar, and the width of the slot, but it could be off enough for it to bind if he wasn't careful.

[bogstandard]

R,

I just made an offering, as I said before, there are most probably hundreds of different ways the problem could be overcome.

I almost always go for the easiest and cheapest.

Bogs