I'm surprised you had trouble with cutter deflection with a solid carbide, normally they would break. A short series one would be a better choice if the work is only going to be 1/4" thick. I play safe and only cut about 1/6 of the cutter diameter depth per pass.

Steve

Adaptive explained here on the Fusion360 site.

**LINK**

Emgee

It's a while since I used CUT2D, only played with that for a couple of weeks and found it too limiting for what I wanted to do. But if using that then select the profile cut and tick "do separate last cut" of say 0.2mm and also tick "3D" tabs which allows you to ramp up and back down rather than plunging.

I tend to use the free version of Fusion 360. So would create three different paths. Firstly one that picks up the two holes at the ends and use that to locate the tapped holes in my tooling block. Don't alter X & Y after this then it ensures work is lined up.

I would then do an adaptive path which is basically a roughing cut to take the work down to shape but leaving 0.3mm radial in this case but similar axial if it were a 3D job. Which gives a part something like this – you can see the curves are slightly facetted and the blue is material still to be cut. The thin blue line indicates the path that the ctr end of the cutter takes while cutting, yellow is when just moving about

I would then do a contour path around the outside to finish the part. I usually do this as one roughing pass of 0.2mm and a final finish pass of 0.1mm which makes up the total 0.3mm I left on the adaptive. You can now see that the remaining blue waste has been removed and the curves are now a lot smoother

That part drawing is what I used on my Victoria, this is the drilling and reaming of the links on the mamual mill before I screwed them to the CNC

And completed

All these cuts would be at full depth, I'm not keen on lots of shallow full width cuts as it just wears the end of the cutter, may as well use all the flute length that you paid for. Probably faster too particularly the 1/4" thick ones.

I've got my version of a James Coombes (minimal castings) on the screen at the moment, will complete the links and video one being cut if you give me a couple of days.

It really comes down to each individual part and deciding what suits that. I do use the contour around the outside with screws or tabs for larger sheet metal type parts but with these links I went adaptive/contour for a few reasons.

1. The metal is supplied as 1/4 x 1/4 and 1/4 x 1/8 flat bar so only way to hold that and machine all the edge is by drilling (& reaming) first then screwing it down.

2. As said above I like to use all the cutters flutes

3. Adaptive tends to throw the chips clear where as a slot or contour in a larger sheet fills with swarf and needs clearing

4. It's a lot faster to do the adaptive & finish contour than going round and round the part in vertical steps or a ramp . For example I would happily be able to run the adaptive & finish contours at a feed rate of 600mm/min and F360 says it will take me 1min 8secs per part. If I do it the other way then i would want to feed a bit slower say 400mm/min and as the tool has to travel a lot further the time goes up to 5mins 16 secs

5. For the 4 short links I only need to drill and tap two holes in my tooling plate. If cutting them all from one I would need 8 tapped holes which takes longer or if I used two hole sand moved the stock about there is a risk of off cuts catching the tool and possible damage.

6. Same as above really the waste material around the part also needs to be held so it does not start to move at the end so more holes to drill or another way found to constrain it.

Coincidentally, last night I was doing the CAM stuff (F360) for another job. I need to cut some 4-bladed fans out of 20g steel, about 90mm across. I shall be using the fan's fixing holes with small wood screws into the spoil board (I use a lump of ply, resurfaced every so often, for this kind of work where depth of cut is not critical – profiling only) plus two more through the waste area – the rest of the waste will have the usual clamps on it. Then it's adaptive clearing plus finishing contour cut for the central hole, and contouring with a couple of step-downs for the external profile. I'm taking that easy because the blades will not be very firmly clamped so a deeper cut to start while there is still material in place to help hold them, and a final through cut with less depth. Then a finishing contour. Jason's point about the build-up of chips in the contouring groove is very valid but not too bad with this thin material. No tabs anywhere. I've become bored with the clean-up needed afterwards! Even with a gentle ramp and triangular tabs it's difficult to avoid some marking.

This CNC stuff needs a bit of thought ("yeah, you just get the machine to do it all, don't you?&quot but it beats the jigs and setups to do it manually.

Andrew, I think some of the people who just want traditional machining think that being able to turn a handle up to a mark on a wheel is a great skill but are not thinking about all the pre and post work that goes into getting the part made. Most of this pre and post work is common to both CNC and non-CNC machining. I am talking about things like figuring out the order of making parts, preparing a piece of stock, making sure cutting tools are sorted out in advance, holding the part to work on it, cleaning and deburring the part after machining, checking it is correct… There are probably other things as well. Marking out to make a part takes a certain amount of skill but how many people nowadays don't bother marking out because they have a DRO? People using a DRO do not get the same sort of digs as people using CNC though.

The actual time a tool is cutting material on a machine is probably not too different for CNC and manual machining.

Martin C

Good to see another KX1 user Steve, and your parts turned out great.

I started out using Cut2D which I found to be very intuitive and easy to use, then progressed onto Vcarve which has a few more useful gadgets like contouring and thread milling, 4th axis etc, it does everything I need and is just as easy to use as cut2d.

IanJ