Guys my QCTP come in from All Industries so my first project for the mill is to actually make something which is the T-nut for the post.Well I am thinking piece of cake nothing to it,well I was wrong what you see in pic took me several hrs.I started out using a 3/4 end mill which from All Industries taking small passes even though I watch a Youtube of Tom's Techniques making the cut in one pass which is about 1/4 x 1/4 I just thinking thats to much for this beginner.I was going to make a pass which was .030 which did OK.On that setting I would rotate the nut and make pass on that side after making several passes I notice that I was not seeing chips and I think it was just rubbing and not cutting on back side with the part on edge.So after awhile I would lay the part flat and make some passes which was little better but I think I destroyed my bit.But the nut fits but loose which I was going for a good fit just to see if I could do it but no go.Guys at first I was making climbing cuts did not realize it till my bit was dull but I was using cutting oil.For while I was at 160rpms hand feeding then I tried 500rpms hand feeding but still like it was pushing against the part.I think that my rpms was way to low plus making climb cuts for the most of the part dull my bit.I want to learn from this but what else did I do wrong or should have done?All this base no problems with the mill itself but going to recheck the head and tram the vise again.
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Milling Question First Timer
- Thread starter Kroll
- Start date
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- Dec 27, 2014
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Is your cutter high speed steel or carbide? We have to know that before offering advice.
Well dang,a beginners mistake.Its HSS,it was a new cutter till my first project.I don't think it cut anything else,I still can't figure out why it would not cut on the side of the end mill but just rubbing up against the material.
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- Apr 30, 2015
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How hard is the steel you were cutting? Have you tried filing it? Hard steels will dull a hss bit pretty quick.
Is this an inexpensive chi-com bit? The quality varies a lot. The edge should be sharp like an xacto knife almost
Is this an inexpensive chi-com bit? The quality varies a lot. The edge should be sharp like an xacto knife almost
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- Jun 7, 2013
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- 10,073
One thing that will help guard against cutting undersize is to do a layout on the part that shows the finished dimensions; lines with prick punch marks so you can see when you are at the finish dimension, when you split the punchmarks with the cut, you can't be far off.
Climb milling should be used only for light finish cuts on a machine that does not have provision for backlash elimination. The 500 RPM would not have been too fast for HSS (good quality) if you were cutting soft steel that would have been easily file able. Yes, your cuts were too fine, the 1/4"X 1/4" cut could have easily been taken in one cut providing the cutter would be well lubricated and not fed overly hard. Over time, you should develop a feeling for how much feed is OK, by feeding by hand and feeling the "feedback" from the cutter; if the cutter is protesting the amount of feed by trying to resist the cut, it's too much.
Climb milling should be used only for light finish cuts on a machine that does not have provision for backlash elimination. The 500 RPM would not have been too fast for HSS (good quality) if you were cutting soft steel that would have been easily file able. Yes, your cuts were too fine, the 1/4"X 1/4" cut could have easily been taken in one cut providing the cutter would be well lubricated and not fed overly hard. Over time, you should develop a feeling for how much feed is OK, by feeding by hand and feeling the "feedback" from the cutter; if the cutter is protesting the amount of feed by trying to resist the cut, it's too much.
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- Dec 27, 2014
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This may sound like a dumb question, but was the cutter turning the correct direction, clockwise viewed from above?
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- Jun 7, 2013
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Another thing that would help us in answering questions, is to post what your machines are, then we might give better advice, knowing what your machine's probable capabilities are.
No question are dumb in my book cause I ask so many.Yes sir it was rotating in the right direction.I don't believe its harden steel cause on All Industries web site says that the nut will have to be machine to fit.I took that it was machinable steel.I did use my bandsaw to cut 1/2 off both sides which it went pretty well.Na I don't know this machine other than the work I did to it.I spent today tramming in both directions and tramming the vise.Its a BP w/2J head 42" table no power feed I believe from the 70's
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- Jun 7, 2013
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The BP should have no problem handling that cutter check tramming alignment.
Stick with it and don’t get disheartened.
I had a similar problem when I started milling. I milled 2 QCTP holders no problem, then destroyed 2 end mills on the third. It seems the third one was much harder steel which was odd as they all came from same supplier.
I’m a long way from expert but reckon steel is hardened or cutters are poor quality.
I’ve also done milling with mill in reverse a few times, but not recently.
I had a similar problem when I started milling. I milled 2 QCTP holders no problem, then destroyed 2 end mills on the third. It seems the third one was much harder steel which was odd as they all came from same supplier.
I’m a long way from expert but reckon steel is hardened or cutters are poor quality.
I’ve also done milling with mill in reverse a few times, but not recently.