Drilling Out Alumina Ceramic Tubing??

[dian]

thwo thoughts:

1. for mechanical material removal shrink a thick piece of tube (ring) on it.
2. if you want to play, get some potasium bisulfate and melt it in the hole. see what happens. maybe a silicone plug would work or teflon, no idea. you might get it in a winemaking shop.

 

[tyreesmuellers]

Wow, this thread is what I was looking for to read more to order essay on the discussed topic. It is amazing. Thank you all for the information. You made my day

 

[crickets]

Came across another cool video from Stefan on doing very small parts, he had sub-2mm solid carbide boring bar from Guhring there :

https://youtu.be/QJIdKqzWuDY?t=275

 

[johansen]

Hi
From my original post:
" The bore only needs to be about 10mm deep.
The hole diameter, concentricity tolerances are wide. I want to epoxy or Loctite a 2mm pin in the bore. An oversized hole can be used to compensate for errors."

buy some 2mm diameter diamond drill bits on amazon for 20$. the kind that sort of look like masonry bits but they sort of have flutes and they are electroplated with diamonds.

 

[Mike Henry]

You might try contacting Cliff Hall (Threadexpress on YouTube). He's also in NZ, does contract work (I think), and seems to have a knack for solving difficult problems.

 

[dazz]

Hi
I have purchased 10x 2.5mm tapered diamond drills from China. They are cheaper than a Big Mac.
I figure the taper will maximise the diamonds cutting the Alumina, increasing tool life and cutting rate.
I have the option of drilling out to a 2.5mm hole, or drilling a tapered socket into the Alumina.

It will probably take a couple of months to ship to my place.

 

[CarbideBob]

That is not going to work.

 

[johansen]

Hi
I have purchased 10x 2.5mm tapered diamond drills from China. They are cheaper than a Big Mac.
I figure the taper will maximise the diamonds cutting the Alumina, increasing tool life and cutting rate.
I have the option of drilling out to a 2.5mm hole, or drilling a tapered socket into the Alumina.

i'm with carbide bob on this one. why not the straight 2mm drills i suggested?
you should be able to find something similar off alibaba or wherever.

Diamond Drill Bit Set 20 Pieces 4 Sizes 1mm 1.5mm 2mm 2.5mm Twist Tip Jewelry Beach Sea Glass Shells Gemstones Lapidary: Jewelry Making Tools: Amazon.com: Tools & Home Improvement

if you don't have much luck using the 2mm diameter as a drill bit, you should be able to use the 1.5mm bit as drill bit and then use a second one as a boring bar and grind the hole out to the diameter you need, rotating the bit as the diamonds wear out.

 

[dazz]

Hi
I was about to buy the straight drills when I saw the tapered versions.
I figured that the straight drills would only last until the diamonds at the tip were worn. Even when they worked, they would leave an internal step stress riser in the bore.

The tapered versions have a lot more diamonds to wear out before the tool is useless. I can foresee that the tool will need frequent clearing of dust to keep the diamonds cutting.

Parallel or tapered, the bits are so cheap, there is little to lose either way.