Cutting really straight holes?

[ttabbal]

Thanks for the great tips on making holes in things! This stage of the project is perfect. 4 holes into t-nuts holding the block down. Everything dropped together perfectly. Spotting drill, then drilled with a cobalt M42 X size drill. I dropped down to about 2000 RPM to lower the pucker factor.

No more crap drill bits. These are from Drill Hog and make the HF set look like I was trying to drill with a screwdriver. Figured I already had them, but no more. I'll use them for wood or something.

Now I need to tinker with the boring head so I can cut counterbores for them. I guess I could use a larger end mill, but I think it will make a good learning project, after testing on scrap of course!

 

[P. Waller]

The end cutting edges of an end mill are not flat but concave, they work fine in this application however.
In production one would use a piloted SHCS counter bore tool https://www.mscdirect.com/browse/tn...-Sets/Solid-Pilot-Counterbores?navid=12106214

 

[TerryH]

I totally cheaped out for these for my plinth project. Doubt I'll use them all that much. They seem ok.

https://www.ebay.com/itm/7pcs-set-Metric-Cap-Screw-Counterbore-Set-3mm-up-to-12mm-part-510-MM-new/161064501615?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

And nice work on your plinth, Travis!

 

[ttabbal]

I thought about those counterbore bits Terry. I have heard that CME has decent quality import stuff. I decided I was unlikely to use them enough to make it worth buying them. Now that I've done that I'll spend many hours using the boring head to do it instead.

I did the boring with my boring head. I managed to get one of them about 0.050 too deep, but I can work with that. It was my own fault, set the stop for the power feed a little off. Just need to cut down the bolts, then mount the top plate.

 

[TerryH]

Wait, I was actually supposed to use all these things I buy?

 

[ttabbal]

Wait, I was actually supposed to use all these things I buy?

Well, they DO look nice in the toolbox...