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Sticky What Machines Do You have?
- Thread starter Jwest7788
- Start date
Johnwa
Ultra Member
Virtually everything I do is a 1 off and usually pretty simple shapes. That said...
yesterday I was squaring off a piece of 4140. HSS end mills did not work. I only have some 1/4” carbide ones. It took a lot of cranking back and forth.. Either full blown CNC or a simplified version that would mill off a rectangular pattern would have been nice!
Tom Kitta
Ultra Member
Get cheap 12mm carbide endmill from eBay. Mine is getting dull after around 10h of work making many pounds of chips. Already have another one ready to take its place. At less then 20 CAD with shipping they are a great deal. Most of my work is in 4140 and 4330.
I rarely use HSS. Almost everything is carbide. Even when getting a bit dull carbide can be pushed and it will still cut.
I rarely use HSS. Almost everything is carbide. Even when getting a bit dull carbide can be pushed and it will still cut.
Dabbler - Now that I've had a chance to play a bit I'll work with King Kong for a while and see how it goes, but thanks for the offer. I can't imagine what it would cost to ship that sucker from Victoria to Calgary. Once I got it remounted it's not so bad but I need to make a speed handle for it.
I really like roughing end mills. They make nice chips & get through material faster. Or do it with less stress on the lighter duty machines, whichever you prefer. But they are not for finishing as they leave a kind of serrated pattern (on the sides) so that means a tool change. So my kind of default mode is a same diameter rougher as finisher like both 3/8 or whatever. Rough to within say 0.020" & then pop the more delicate tool in so you don't have to change setup too much.
My machine came with two 3" four flute carbide tipped fly cutters, I played with one the other day and saw what you mean about the serrated look. I shaved off .050 like it wasn't even there, this sure beats the hacksaw for roughing and file for finishing method I've been using.
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Thanks Peter, I’m on the verge of ordering some end mills from KBC.
I have matching diameters in roughing and plain.
Just so that I’m clear on what’s happening:
Rough mill first then follow with a plain end mill of the same diameter, same table position and it will remove the ridges left by the rough mill?
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Dabbler
ersatz engineer
@David_R8 Roughing end mills require less force to cut well, sacrificing surface finish in the process. There need be no correlation between the sizes. I thing roughing end mills in larger sizes work best...
@YotaBota, @David_R8 I travel to the Island every year. we should do coffee, at least. Perhaps the 3 of us? I'm working to going to Victoria early in the spring.
@YotaBota, @David_R8 I travel to the Island every year. we should do coffee, at least. Perhaps the 3 of us? I'm working to going to Victoria early in the spring.
Don't forget me.
It can work to your advantage that way in many instances but its not a prerequisite at all. For one thing, I've found roughing EM's to be wider tolerance variation than regular EM's. So if you are doing profile cutting you can't necessarily count on x,y coordinates to yield the proper dimensions swapping in the finishing EM. Its better to leave some over stock with the rougher, say 0.020", drop in the finisher & measure actual dimensions like you normally would. It really depends on the rougher because there are coarse & fine ones & some with varied geometry that take aggressive cuts but finish is a bit improved... Anyways I'd guess at least 0.005" worth of serrations after roughing so you want to give some allowance for finishing. I'm talking the side of rougher, the finish of the bottoms are actually quite clean looking.
In other cases a bigger diameter rougher tool may be better suited for hogging but its all about trade offs. You get more tool rigidity, you can remove more stock, but you have to have the power & clamping rigidity & rpm range & that can make more heat.... etc
Dabbler
ersatz engineer
+1 to what Peter said.
My plan is to go hiking on the North Coast trail, so I'll be in Victoria for a half day or so. Would love to 'drop in' a few shops if not too intrusive. And coffee, of course. If I come too early, then the trail is closed, but there's still a lot do do on the Island. Oh and visit Alan in Nanaimo, of course.
My plan is to go hiking on the North Coast trail, so I'll be in Victoria for a half day or so. Would love to 'drop in' a few shops if not too intrusive. And coffee, of course. If I come too early, then the trail is closed, but there's still a lot do do on the Island. Oh and visit Alan in Nanaimo, of course.
Cape Scott is on my bucket list, I just need to get there. My shop is not going to be feasible as you'd spend half of your time behind the wheel but coffee and a bs session sounds good.
Peter T - understood on the roughing EM, I have a ways to go getting the terms correct.
Peter T - understood on the roughing EM, I have a ways to go getting the terms correct.
Here is a picture of my manual lathe. First thing I did was put a single phase motor in it. Oh and I had to weld the x axis acme screw back together because it tipped over during loading. But it was free. A friend was hauling it to the scrap yard and offered to drop it off in my garage. Last night I decided to put a self centering 4 jaw on here so I can quickly turn some square stock round. I like the 4 jaw self centering. Not sure why most people buy 3 jaw chucks? Now I have both to play with.
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Good score Alex!
Maybe because of the old tradition to make your own bolts from hex stock? Nice Rohm 3-J btw.
Maybe because of the old tradition to make your own bolts from hex stock? Nice Rohm 3-J btw.
Johnwa
Ultra Member
@Alexander I want to get to know some of these friends of yours!