120 DEG Drill points in a Mainfold.

[crazy^millman]

Okay so I have a project that has 2 manifolds. The parts have a 120 deg drill point in the bottom of all drill holes. The intersect and where they intersect all transitions cannot have a sharp edge or feather. They have to be with .03R to .06R everywhere they meet. I asked for a ruling since I am using coolant through 130 deg drills I was thinking of just hitting the depth remolding the area where 130 hit and then program my blends from there. Never got an answer so I am trying to finish up my tool list and running out of time.I am thinking I either have from tools made with the 120 deg points for my 15 different sizes which means a whole lot of custom tools, go to gun drills which seem to be about the only thing with 120 deg points that will be 10 to 20 times longer than I need. I have even bounced around 120 included angle chamfer mills but hanging a 1/2 tool 2.4" out to machine a drill angle does not sound like fun either. Flight Critical parts and already had a REV Change in the process. What have those of you that have had to deal with parts like this done?

[Guyinthedesert]

Some engineers are more flexible than others, and it's sometimes hard to guess. There may be no reason at all for a 120 deg pont, or there may be a real good reason. Can you drill them with your coolant through drills, a tad high, then go back in with a HSS drill ground to 120 deg and pick out the point?

[MIL-TFP-41]

I saw this tons at my last gig.....we even just expected it. At first we did what you first suggest, run your high performance 130 deg drill to depth then chase it with a 120 deg point. That made our tooling packages much larger than it need to be, so we had the crib modify the drill points to 120 deg. This worked better than expected. We did have to spot drill the holes first tho. Material was 7050 alum. Our typical tool package for finishing a large manifold could run well over 200 tools...so i can relate on trying to minimize your package.

[THEE THAINZ™]

Do they have a form or angular tolerance? If they have a form tolerance and the 120 deg drill point is listed as a feature not angular can you use that to your favor?

[crazy^millman]

Thought about going with the 130 degree tools made into 120 degree, but was trying to avoid that as well. 7075 so right along with what you were thinking.

 

Yes Angular tolerance of .5 deg so the 118 was out as well. They went by the AS5202 tool ends and are just not educated on manufacturing processes. Some have a .015 area left of the drill point and I have to figure out how to fit a .03R blend from that to the adjoining hole. Good times and I let the project manager know 25% of the programming on these parts is the remodeling of the parts to make them. 25% of the project was the tooling that needed to be called out. The other 50% was the actual programming of the parts. True to form he was unaware there was that much involved, but of course are you done yet?

[Jayson Kramer]

Ron is this that local customer to me? I am going there today if there was something you wanted me to ask? if not then of course never mind.

[crazy^millman]

Jay, thanks I have already asked all the questions. Just pressing on to get it done.

[Zoober]

Ron is this that local customer to me? I am going there today if there was something you wanted me to ask? if not then of course never mind.

Ruh roh.....

[Jayson Kramer]

Ron, All good.

What is up Mr Zoober?

[crazy^millman]

Not where you use to work sir. They burned me years ago and I learned that lesson.

[MIL-TFP-41]

Thought about going with the 130 degree tools made into 120 degree, but was trying to avoid that as well. 7075 so right along with what you were thinking.

 

As much as I hate using non "off the shelf" tooling sometimes it's the nature of the beast. At least in 7075 you can expect decent life. Custom tools in Ti or 15-5....yikes on having to stock customs.

 

 

Sent from my iPhone using Tapatalk

[Zoober]

Not where you use to work sir. They burned me years ago and I learned that lesson.

That's what's up Jay.

I still feel bad about that.

[crazy^millman]

That's what's up Jay.

I still feel bad about that.

 

It was not your fault and never thought twice about it till this thread. Things happen for a reason my friend and been great to work with you in the different place I have had the chance. Going up to Oregon was fun that time and we would not have the kick butt Renishaw Macros had it not been for that work so many years ago we worked on together. Many blessings over the years and even the ones were things go wrong are still blessings.

[Zoober]

I agree. We are blessed men.

I would not be at the best shop eva had I not worked there. The way you were treated was the beginning of the end for me there. You just don't do that to people. Specially friends of mine.

Those macros are cool, aren't they?

They are in all the posts I make.

[greenxman]

i use cobalt screw machine drill in 7075 all the time and they come 118-120 tip split point. from msc and they are cheap

just a thought

[mike93]

another engineering missteps that make a part twice the cost if------??

[crazy^millman]

Well I am hoping the customer has some stuff already bought for the sizes we are doing. If not I will call something out and yes so much extra work on this part that is really not needed. I need it for hole sizes from .321 all the way up to 1.708.