Level of precision

[gocy]

Just found a pair of these for sale

http://www.miyanaga.co.jp/engl/products/metal_borer/mb350500.html

Has anyone used these before? Do they produce a precise hole or is this tool used for roughing?
thanks in advance

 

[Tin Falcon]

Imho not something needed or particularly valuable for a home shop model maker.

The web page states under application.

Best for boring operation in shipbuilding, bridge building, framework building, and steel structure building.

Has anyone used these before?

When i worked in a steel fabrication shop we used similar bits for drilling the holes in the steel beams and columns.

so unless you are going to build a steel building bridge or ship NO.

Do they produce a precise hole or is this tool used for roughing?

A rough hole as they are intended for a large bolt to go though.



Typically in a machine shop one drills a hole with a drill bit then enlarges the hole with a boring bar on a lathe or boring head (with boring bar) on a mill.



Tin

 

[jwcnc1911]

I have used similar tools for the last decade. Some very high precision, some horrible. Most people refer to them as a holes saw or hollow mill. Those appear to be carbide tipped and of high quality.

I must ditto Tin in the previous post. For a home modeler those would probably never get used unless you used it just to use it. In the last 10 years I've used those on 3 different parts, all with out the pilot for the specific purpose of leaving a post.

Also google: annular cutter

Spend your money on something more useful... you can never have to man 1/16 to 5/8 or 2mm to 12mm endmills. Trust me.