Radius intersecting holes Recomendation

[RaiderX]

I have a part with two .25 diameter holes intersection (one internal to a bore) that require .05 radius at intersection. Print tolerance is +/-.01 .

 

any ideas.

 

 

[djstedman]

Does sending the engineer to the firing squad count as an idea?

 

If its actually necessary, perhaps a mini right angle head with a custom lollipop and another snaked down through the 1/4 hole, from the picture it looks like the tools would have to have a tiny shank though .. this is why engineers should have to work with a pen and paper and run a machine for a few years before working in a shop as an engineer.

 

I'm probably a horrible person for thinking this, usually I love a challenge, but in this case I am glad this is someone else's problem.

[specv]

This is about the best you are going to get, not sure about the +/-.01 though.

http://www.jwdone.com/

[The Cathedral]

Pencil grinder and a bottle of Xanax.

 

I second the Orbitool suggestion. Getting it to cut the right size radius is going to take time and trial and error, since there's no way you can "program" one of those tools, but once you get it it should stay consistent.

 

Then you get the next problem: how you gonna check it?

[RaiderX]

thanks all. just sent a message to jwdone. will let you know how it turns out.

 

think I am going to have to use test pieces to dial in (can cut them in half for inspection) but the real one is going to have to be on inspection cause Im at a loss on that part.

[crazy^millman]

Liquid hone it. We have companies out here that will drive a medium through the part and create that radius for you.

 

Here is the patent information on the process:

 

https://www.google.com/patents/US7063594

 

Here is a company that offers the service.

 

http://www.extrudehoneafm.com/

 

HTH

[Del.]

Could you EDM it?

[RaiderX]

Nope. its 1970's Aerospace hyd. fitting work.

[Sticky]

I'm not seeing why you can't use a Harvey 270* ball cutter and just surface it?

 

I'm actually doing just that on some cross holes right now.

[Guest]

Flowline toolpath with no gouge checking and direction is your friend. :

[RaiderX]

am trying to stay away from a .062 shank tool hangin 1.3 ooh.

would be one way to tackle this. tho

[Sticky]

am trying to stay away from a .062 shank tool hangin 1.3 ooh.

would be one way to tackle this. tho

 

What is the diameter tolerance of your .25" holes?

[RaiderX]

+/-.01 but already established

[Sticky]

Oh I thought that was tolerance of the rad.

 

 If the hole is at least .25" you could probably use Harvey tool #979216. Otherwise maybe #979212. Might not get that full .05 rad. Might have to go to a full rad key cutter for that?

[GoetzInd]

I was going to point you to harvey byt Sticky beat me to it. Can you put it on an HMC or 5X?  If so, give it a tilt and hit it with a flowline.

 

Mike

[civiceg]

How many do you have to make? Im sure that radi was spot on in 1970

[Newbeeee™]

How many do you have to make? Im sure that radi was spot on in 1970

Exactly. That was done with a windy/rotary burr on a bench with a good eye back then.

[civiceg]

If its a production run sure by all means invest the resources. It looks like a bleed/vent hole....

[RaiderX]

We got the tool from JWDone. great support, instructions and communication.

Foreman made the call to have a senior machinist work it by hand with this tool. worked great. I mentioned senior machinist with intent of more experience in the crafts than I (I am pushing over 30 years machining) so I think he was key.

am anxious to get this in a cnc to see what kind of results we can get but that will have to wait for another job in need of this application.

will try and post results when we do.

 

thanks for all the idea's

Doug