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5

I'm assuming that you are cutting on a base sheet of some sort in my answer, if not, please do. In all my shop applications I have found that double sided taping the product to the base sheet is sufficient when my machine doesn't have adequate suction.


4

Because some programs for some operations can be written quicker than the time it takes to produce the equivalent CAD file. Also use of variables makes the program more useful ie a program to produce a cylinder can be written to take diameter as the controlling argument while producing many CAD files for various different diameters takes time.


4

On a mass manufactured part, one solution is to cast the piece and shape the die (with an inside fillet) to form an outside fillet. Of course, if you want your casting to have an inside fillet, you'll need an outside fillet on your die. Assuming you're not casting, and working with a commonly machinable material, external corners would typically be rounded ...


4

No milling operation will give you a perfectly flat surface. The level of finish you can achieve will depend on the capabilities of the mill itself, the tooling you use and how the tool paths are set up. Also when facing. Because you are cutting with a rotating face you will inevitably have one side of the tool moving int other direction of travel and the ...


4

The two existing comments are correct IMO, it's mostly due to economics. The price to produce comparable CNC and manual machines might be close, but the demand for CNC's is much greater than manual machines. Every shop I've ever been in, from mom & pop places to 1,000+ employees, has been 95% CNC with manual machines reserved for tool & die making or ...


3

Take this all as very general....Flutes of a drill bit are ground only for chip extraction, where as end mills take the chip extraction flute and grind an actual cutting edge on it ( b - c ) and some relief (c - d). Picture is of a 4 flute end mill, the one on the left being proper. There's MUCH much more to cutting tool geometry than this brief explanation, ...


3

It should be doable by hand; the Quora answer missed what I found to be the most important factor for cutting Ti; use chlorinated cutting fluid like carbon tetra chloride. I once drilled small holes ( 1/8 ") in grade 2 or 3 ( lower strength more ductile than 5 ) ; I broke a bit ( high speed steel, not Home Depot) before making the first hole . I used the ...


3

First, we should recognize that parts aren't just blindly thrown onto a table and a generic mill used to cut whatever shape we want. Each part requires the proper tooling and fixturing. On a production level, the tooling is probably going to be a standard set of tools that you select from for most parts. Depending on what kind of parts you are making, ...


2

Before we get into calculating the best feeds and speeds for your goals, there are a few more concepts we need to understand. Chipload: Chip Thickness per Tooth While feedrates are specified in length units per minute, the more important measurement is something called "Chipload". Thing of a chip as looking something like a comma in cross section, or ...


2

Depending on whether that's one-off or something to repeat, a properly shaped bit with "negative curve" will be the most efficient (single pass) and neat (no grooves from multiple passes) solution. I don't have a photo of the tool in question, but the one in the middle has some similar properties - it was used to create undercuts (-30 degrees edges) and ...


2

I found one of those printer things that puts ink on dead trees and tested to print a simple SVG file. <svg xmlns="http://www.w3.org/2000/svg" width="400px" height="800px"> <rect x="10" y="10" width="72" height="72" fill="#999999" /> <rect x="10" y="100" width="378" height="378" fill="#999999" /> </svg> As I suspected 72 ...


2

A groove will have a very slight internal radius in its corner, but if this is undesirable, then a relief grooving tool is used to remove this material. The relief grooving tool comes in at 45 Deg to cut as shown:


2

What you're looking for is called "Wrench Clearance". There are tables for these in Machinery's Handbook (pp 1344-1355 in 24th ed). There are also resources online like this table for box end wrenches or this one for open end wrenches I will caution you that the clearances listed in these types of tables should be considered minimums and more is generally ...


2

The problem is that the CSV export is including the new line characters that are part of the hole callout. So this: A1,2.07,9.78,<MOD-DIAM> .257 THRU 5/16-18 UNC THRU should really look like this: A1,2.07,9.78,<MOD-DIAM> .257 THRU 5/16-18 UNC THRU You can perform a string replace of any pair or new line characters with some delimiter of ...


2

Not what you're asking for, but maybe even more suitable? These are also available in a low-profile version. Google "toggle clamp". Or these? Google "spring plunger".


2

As you have the "pocket" already, one method would be to have holes in the pocket base and use a vacuum cleaner to "suck" the piece down.


2

The standard solution is to use milling clamps. These consist of a screw that fits in the T-slots on the milling table, and a sturdy metal fitting that holds down the work. They're available in various forms to fit different situations. Spring clamps would have to be massive to provide enough force to keep the work from sliding around. But your solution ...


2

Well if engineers didn't learn G-code, why even learn what tool will be operated? Does it matter if its a lathe or mill or multi-axis something? It just produces a part that's an exact match of the CAD model, right? I think however this assumes too much perfection and reality in the abstraction of a CAD model. At the very least as a teaching device it is ...


2

If the alloy is magnetic then you can use a magnet as the cut is nearly complete to fix the cut out part in place as the cut finishes. If the CNC doesn't allow that then you can instead let a few tabs remain and cut them out on another machine where the center part is properly held in place.


2

You can certainly drive the cost down by injection moulding the plastic parts. It has a relatively high setup cost though. Acrylic can also be extruded. In both cases laser cutting is probably also much faster than you think. Just be sure to choose the right laser: what takes forever in a fablab can take seconds in a real high power laser setup. Anyway ...


2

You could look into Protolabs. They provide a range of services from 3D printing, CNC machining, short run injection molding using aluminum tooling, production molding and more. They are really fast. They have an online quoting and ordering system which includes an analysis of the moldability of your part. Low cost aluminum tooling is cheaper and faster to ...


2

Judging from the pictures, they are CNC machined out of solid aluminium. That isn't an expensive process, so long as you have the CNC machine. A basic one that isn't junk for sale on E-bay would cost a few thousand dollars, which isn't a big deal for a commercial company if their selling price amounts to hundreds of dollars per hour of machining time.


2

These types of molds are for casting and curing. There is basically zero injection pressure so they can be small and require minimal machining. You can keep them closed with paper binding clamps. You can see from the photo they took a piece of stock aluminum, faced it with a fly cutter and machined the cavity. Easy and Inexpensive. When you inject ...


2

The methods available to a hobbyist are akin to that of the production world, in that one needs only a controlled heated implement traveling in a restricted manner. A drill press with a long bolt threaded to match the insert provides such restrictions. Heat can be applied to the insert and the quill lowered into the part, which is secured appropriately to ...


2

Some threaded inserts have flanged faces for a few reasons, one being that if you press the flange flush to the surface around the hole you're tapped hole will be relatively perpendicular. These can just be hammered in. Others, typically "self-clinching", are installed with arbor presses and some degree of attention by the operator to maintain ...


1

If you operate a cnc machine you will learn g-code eventually. Even if its just a subset of the g code. The reasons are numerous but mostly it boils down to: You need to setup the machine and tools from time to time. Then it might be practical to be able to write short snippets to change tools, work coordinates etc. I mean this isnt really magic its more ...


1

It's going to be an uphill battle from that point on. While you can get every part of the machine and the process to tighter tolerances, their errors may compound to the sort of tolerance of 0.025; you may manufacture relatively simple parts with lower error but whether you succeed or not is more up to luck than your efforts - whether the tolerances of the ...


1

Aluminium foil will probably shred. Stick it on the back of a cardboard,maybe? I would rather use a blade or scissors. For 1 mm aluminium you should try to use low feed rate (x and y axis speed) and depth of cut (z depth, which corresponds to number of passes) and iterate till you get desired finish and productivity of the machine and tools. Pair it with ...


1

This is what Inventor recommends for a clearance hole: And for a tapped hole:


1

This is one of those questions that can be answered by "you get what you pay for." Ignoring the poor grammar of that statement, one does have to spend money for quality performance. In the 3D printer world, you'd have to have as much as 0.2 mm spacing to ensure the rotation you seek. In the CNC world, it's not that large. A friend who owned a machine shop ...


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