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Drill Speed
I want to put twist drill of dia 21.5 and 23.5 on my machine. My daily requirements would be more than 1000 holes per day. Have majorly used has drilling on radial drills and annular cutter on magnetic drills.
Annular cutters are not suitable in cases where stacking is preferred. HSS twist drills are not so fast.
I am currently developing a CNC drill machine, and I need to find the right speed(s) options that I need to design for.
Details
Drill dia 21.5mm or 23.5mm
Material Steel low carbon, BHN around 150, normalised.
Drill Type HSS twist drill.
What if I upgraded to a carbide tip twist drill, something like Sandvik Coro 870. What speed would these like at the same diameter?
Thanks
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Re: Drill Speed
hy :)
hss drill requires torque @ lower rpms, while carbide requires higher rpms
hss feed/revo may be > carbide feed/revo, but because carbide can operate at higher rpms it will achieve a higher linear feed, thus in the end, feed/min will be higher with carbide
you can not compare hss and carbide, for the same tool diameter, at identical rpms, simply because hss and carbide operate at differents rpms, because their cutting speeds are not identical .... in short, hss requires more torque at low rpms, while carbide is the oposite
if you wish to improve stability with carbide, switch to u-drills : their inserts are less $$$, life spam is ok, they will go over missalignments more easy, and they require less spindle torque compared to classical indexable drills
however, there is a catch with u-drills : they do not handle well depths>7D, and the u-drills with inserts with 4 cutting edges do not run as smooth as those with only 2 cutting edges
how does your fixture look ? and what is the depth of the hole ? kindly :)
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Re: Drill Speed
someone write an article on this topic. you can use this site https://residencypersonalstatements.net/ I often need to drill and sometimes I break it. in general, I need information on how to do it right. Thank you
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Re: Drill Speed
The cutting speed for a HSS twist drill depends on the material being drilled and the diameter of the drill. For a 21.5mm or 23.5mm diameter HSS twist drill drilling low carbon steel with a BHN of 150, a cutting speed of around 50-70 meters per minute is a good starting point. However, this is just a rough estimate and the actual speed will depend on factors such as the specific geometry of the drill, the cutting conditions, and the feed rate.
If you upgrade to a carbide tip twist drill, such as the Sandvik Coro 870, you can expect to run at higher speeds compared to HSS twist drills. This is because carbide drills have a higher heat resistance and better wear resistance, which allows them to withstand higher cutting speeds.
https://jaibros.com/products/u-drill1-mm