Fusion Friday #4: Cut Sweep a Knife Blade!

[@joell439]

John, anyone can learn to this stuff with your great tutorials combined with your amazing subscriber's additions. What an awesome group of people willing to share what they know. Merry Christmas.

[@chrisarmstrong4395]

I've played with this quite a bit lately. Instead of trying to manually create a sweep path, just create your offset plane/profile exactly like you did, then pick the bottom edge of the blade as the sweep path. You can choose which direction to sweep it, go toward the tip, done easy. This makes it easy to simulate a full flat grind as well (bevel goes all the way from bottom to top of the blade), and still get the top/spine of the blade to taper down to the tip. Thanks John as always!

[@BigMjolnir]

John, Merry Christmas! Your dedication to keeping the Friday video schedule despite holidays, flying reindeer targets, and mistletoe overcast is duly noted. Thank you! Now it's back to Fusion360 learning and welding cart design for me! -- Mike

[@GregsGarage]

Not sure the path's arc was concentric. In order to be concentric, I believe both arcs need to have the same center point, not the same radius. Not sure if Fusion has an edge offset command, but that should be the quickest way to go.

[@panepuccrex]

Merry Christmas to you and your family and a Happy New year. Can't wait for the videos coming in the new year and seeing the new shop coming together.

[@braxtonec]

Good stuff! With this and the series on joint/part assembly we've gotten a taste of CADing a knife. I know there's way more to it but the foundation knowledge is quite helpful! Merry xmas!

[@MUKnives]

That is the way I did it with Solidworks. I have to use PTC Creo now (former ProE) which is quite a lot more difficult. Thanks John! Merry Christmas!

[@jamesdolan3386]

The way i do blade grinds is with a chamfer set to angle and a distance. Depending on the blade, the angle usually varies from 6-10 degrees and the distance is the width of the grind. Really simple way to do it an it can be easily modified to adjust edge thickness. Another benefit is that the grind width will be consistent for the entire blade. It appears as though the arc you used for the sweep was not quite concentric to the profile of the blade

[@jamesdolan3386]

+NYC CNC I think what happened is that you set the center point of the arc coincident to the vertical reference line. If I were to do the sweep, I would project the curve of the blade profile into the sketch and create a concentric relation. Nevertheless, great video and I always enjoy your content. I have been using the student versions of Solidworks and Siemens NX for a while, but I wanted to work on a commercial CAD license for personal use. I was pulling my hair out trying to find a full featured comparable solution that didn't cost several thousand dollars. I discovered fusion 360 from your videos and I'm really glad I did! I'm still adjusting from Solidworks, but the free-form modelling tools and CAM in 360 are like none other.

[@specialks1953]

Merry Christmas and Happy New Year to All at The Shop and Your Whole Family!

[@EZ_shop]

Very good explanation/demonstration and at the right pace John. Merry Christmas to you as well.

[@vdub5818]

FWIW always leave a good amount of edge thickness so it doesnt warp during HT and also leave some after finish milling for some strength. Of course it depends on the steel used but .025 is a good number for most stuff

[@vdub5818]

+NYC CNC ahh i hear ya. Merry Christmas sir

[@ToddKerns314]

Nice video showing some more obscure features of Fusion360. Great example.

[@TAWPTool]

Merry Christmas to the Saunders family! Great video John.

[@cbyrd4423]

Merry Christmas to you and yours ! Chris

[@zebratruck]

John, can we see this one get cut? I assume you'd have to do one side the flip the work piece over? Or chuck it up vertically and it would cut both sides?

[@bdugh]

John, Merry Christmas to you and your family.

[@danmartinguit]

Thank you very much Mr. I am new to Fusion 360 and that helped me tremendously !!! Keep up the great work !!!

[@sharpx777]

can you select the edges and offset entities (like in Solidworks) instead? not sure if it would work to do the sweep using that though.

[@helicrashpro]

To make those sweeping lines concentric you would have needed to take the distance from line to line (start point) and subtract it from the radius of the first line you made, which would give you the radius of the second line. This would make them sweep concentrically. Whoever, artistically, not having them concentric could make the knife more appealing.

[@stormbringermornblade8811]

Merry Christmas .

[@sachie123]

Merry christmas john...hope to pick up a new pc on boxing day an will get into fusion360.

[@brianmiller9850]

Great video, John! Thank you and Merry Christmas!

[@tizwicky]

Merry Christmas!

[@AdMan-The-LabRat]

That is really cool, so basically "the variety of blade grind" = [(knowledge of the software) + (your imagination)] - (limits of the tool) given: respecting the constraints/characteristics of the material worked?

[@886014]

Hey John, as an idea for Fusion Friday I'd like to suggest a few videos on sending models to drawings. Strangely drawings are not something I typically use, but should. I've never been terribly enthusiastic about F360's drawing functions, so I should probably get more time using it. Edit: Just in the interests of completeness, the issues I have with the drawing function in Fusion is that it's glacially slow, even on a powerful Macbook., clunky, and worst of all the dimensions almost always don't pick up the features correctly. Having just been trying to use it again today, I do not like this part of the program at all and feel it needs urgent work by the F360 team.

[@GregZuro]

I think that if you make the two arcs actually concentric as the other greg suggests, then you will get the two faces to meet at the tip as you intend.

[@ChristopherHirsch]

+NYC CNC no you have two equal radius arcs with different center points. What you want is to have coinciding center points (concentric circles)

[@williamhardin5254]

+Christopher Hirsch I agree Chris, they were not quite concentric witch is why is wasn't sharp all the way up the tip of the knife blade.

[@rlockwood2]

+NYC CNC really, there's no need make guide geometry here anyway, you want the grind to follow the blade profile, just select the blade profile. If you want more control, you'd select two guide curves, which gives you control over how the profile curve rotates along the guides.

[@rlockwood2]

William Hardin​ yeah, but there's no point in even offsetting it. Offsetting the guide doesnt make any difference, and really only offers the opportunity to make mistakes and have the edge thickness either increase or blow out the profile, both shown accidentally in the video :)

[@williamhardin5254]

+rob lockwood You know what, I have no idea of what his design intent is so I'm not going to comment on what he should or should not have done anymore.

[@paulfle]

The easiest way to fix the material at the tip being left over would be to use the offset tool to generate the sweep path.

[@SeaMushroom98]

i'd think that you could just trace over the curve and then say offset entities, but I'm a solidworks guy, so I've never done it in fusion.

[@Regular6782]

That wasn't concentric arcs. You would need to find the center point of the first arc and make your other arc with that center point. If you draw them as full construction circles you will see what I mean. Great video though mate. Cheers.

[@GeofDumas]

The more demos you make, the less I understand how it's only $300/year. Lower cost, I would expect, but not lower than Adobe CC. I might get it just so I know how to use it!

[@AdMan-The-LabRat]

1st: 🎄Merry🎄Christmas🎄

[@dannyesparza9110]

can anyone help how do i use g42 or g41 on my tormach i try and i have fusion 360 and everytime i choose in wear or control wear it gives me a post error do i run the program under a different machine? because sometimes i have to redo the program and its time consuming and a waste of time and its faster just putting your tool wear in the control and run again . thanks

[@dannyesparza9110]

+NYC CNC well its a half a page but the important thing i see it says is error: failed to post intermediate NC data. code page changed to 1252(ANSI - LATIN I) generated by : fusion 360 cam 2.0 1774 Warning:work offset has not been specified Using G54 as WCS. Error:radius compensation mode is not supported by the cnc control. there is more but its to long to write but this is the important part . i still use Mach 3 i draw the part i want to work on and lets say its a bore op i need to open it .002 more i have to go back to fusion change the tool path then open it up .002 more and normally it should be in the tool table you can control the wear and run it again , sorry if this is long and thanks for the help John.

[@dannyesparza9110]

+NYC CNC and this code only happen if i put wear in fusion but if i keep it in "in computer " it doesnt give me an error it runs fine.

[@uzkanda]

sweet

[@eddrm4685]

Merry Christmas.