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Hobby CAD, CNC machining, and resin casting (2015)

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Re: Hobby CAD, CNC machining, and resin casting (2015)

#61

Post by potato3732842 »

syntaxing wrote: post #7

Former MechE for a decade and I owned personal CNC routers and on my 6th 3D printer. The biggest issue with CNC is the cost for consumables and accessories. Need a special bit? $$$ Need stock to cut? $$$ Want a nice ER11 or R2 collet set? $$$. A nice vise? $$$ Cut something wrong with a carbide bit? Shrapnel explosion. 3D printing has a bunch of limitations but is a way better machine for hobbyist. But I have been ey…

I'd just like to point out how stereotypical of a modern mechanical engineer it is to want to print everything out of plastic and not appreciate the greater versatility of a CNC router.

I can't count the number of times I've converted gasketed joints into O-ringed joints, slotted holes, casting lines and welds I've smoothed out. Yes, there are better machines for performing these tasks in metal but I can just tell the CNC router to go nice and slow and come back hours later. In addition to that there's all buffing and polishing operations you can do with abrasives and the ability to cut cheap wood templates and test parts. The 3d printer can make complex things relatively quickly and easily but it can't work with existing things.

Re: Hobby CAD, CNC machining, and resin casting (2015)

#62

Post by potato3732842 »

eth0up wrote: post #58

To the machinist/s here: For nearly a year, I've been contacting local machinists for a small[*] project which involves 1) an accurate cut on both ends of a 17" billet of T6061, 2) two crescent cuts, 3) up to 8 threaded holes, but probably, 4) a wee bit o end shaping. All the aesthetic contours, shaping and weight reduction I'd do manually - I hand machine bronze, aluminum and wood archer's thumb-rings, so can wangle…

Find a hobby machinist.

People who aren't trying to expand their business don't want to deal in non-gravy projects from customers who don't seem likely to shovel them a bunch of gravy projects later.

Machining is a slowly dying industry in the west so there's far more people not growing their business at any one time.

Re: Hobby CAD, CNC machining, and resin casting (2015)

#63

Post by potato3732842 »

blackeyeblitzar wrote: post #35

Has anyone here tried using CNC machines for gunsmithing as a hobbyist? Is that even feasible? What about 3-D printing metals instead of plastic? To be clear, I know little about either firearms or metal working, but it seems like it would be an interesting engineering challenge for a hobbyist.

You can do it but don't expect top notch results.

Routers don't have enough rigidity (this is why you don't see gantry mills except in huge sizes) for the kind of work you'll want to do. So much of your stuff will be one off that you're not going to have any speed advantage over a guy with a Bridgeport.

Re: Hobby CAD, CNC machining, and resin casting (2015)

#64

Post by potato3732842 »

Joel_Mckay wrote: post #15
syntaxing wrote: post #7

Former MechE for a decade and I owned personal CNC routers and on my 6th 3D printer. The biggest issue with CNC is the cost for consumables and accessories. Need a special bit? $$$ Need stock to cut? $$$ Want a nice ER11 or R2 collet set? $$$. A nice vise? $$$ Cut something wrong with a carbide bit? Shrapnel explosion. 3D printing has a bunch of limitations but is a way better machine for hobbyist. But I have been ey…

A reasonable quality plasma-cutter CNC table offers the speed and low operational cost most fabricators can manage well. Having a CNC Router table in a non-industrial zoned area will not work for most people. Services like sendcutsend.com makes life so much easier... =3

>Having a CNC Router table in a non-industrial zoned area will not work for most people.

Lolwut? Throw it inside where the narcs can't see it (you'll want it inside or at least in an out building anyway). They're not loud. The venting you'll want isn't loud either.

Source: I do this stuff in my house.

Re: Hobby CAD, CNC machining, and resin casting (2015)

#65

Post by WillAdams »

throwaway81523 wrote: post #54
Animats wrote: post #52

Earlier quoted context omitted.

DIY knife forging is common. Search "knife forging". Look around for classes and forges with training. There's a huge amount of info on knife making and metallurgy. People obsess on this stuff. A good knife is a trick of metallurgy. The blade must be hard at the edge to be sharp but ductile in the body so as not to be brittle. How to do this is well understood today, but there was much mystery around it for centuries…

Sure, knife forging is one thing, but the idea of making replacement blades for folding knives sounds like it takes machining, because of the weird shapes needed at the pivot end, especially for weird locking mechanisms. It would be nice to be able to do that at a semi-commercial level if one were to get into it at all. Victorinox is on a completely different scale, making millions of units of whatever. But forging i…

We (ob. discl., I work for Carbide 3D) have a video series on doing this:

https://www.youtube.com/watch?v=G5TYla5x-Nk

Re: Hobby CAD, CNC machining, and resin casting (2015)

#67

Post by Joel_Mckay »

potato3732842 wrote: post #64
Joel_Mckay wrote: post #15

Earlier quoted context omitted.

A reasonable quality plasma-cutter CNC table offers the speed and low operational cost most fabricators can manage well. Having a CNC Router table in a non-industrial zoned area will not work for most people. Services like sendcutsend.com makes life so much easier... =3

>Having a CNC Router table in a non-industrial zoned area will not work for most people. Lolwut? Throw it inside where the narcs can't see it (you'll want it inside or at least in an out building anyway). They're not loud. The venting you'll want isn't loud either. Source: I do this stuff in my house.

Are you using a full sized "router" on steel plate, or a mini-engraver made from a hobby-motor on balsa? Even a compressor fed Plasma-cutter rig is usually far quieter by comparison, as cheap import engravers often just make a mess of the surfaces.

Best of luck, =3

Re: Hobby CAD, CNC machining, and resin casting (2015)

#68

Post by mvidal01 »

syntaxing wrote: post #7

Former MechE for a decade and I owned personal CNC routers and on my 6th 3D printer. The biggest issue with CNC is the cost for consumables and accessories. Need a special bit? $$$ Need stock to cut? $$$ Want a nice ER11 or R2 collet set? $$$. A nice vise? $$$ Cut something wrong with a carbide bit? Shrapnel explosion. 3D printing has a bunch of limitations but is a way better machine for hobbyist. But I have been ey…

The Millennium Machines Milo does look interesting. I wish there was an inexpensive cast iron or epoxy granite equivalent to aluminum extrusion.

Re: Hobby CAD, CNC machining, and resin casting (2015)

#69

Post by eth0up »

potato3732842 wrote: post #62
eth0up wrote: post #58

To the machinist/s here: For nearly a year, I've been contacting local machinists for a small[*] project which involves 1) an accurate cut on both ends of a 17" billet of T6061, 2) two crescent cuts, 3) up to 8 threaded holes, but probably, 4) a wee bit o end shaping. All the aesthetic contours, shaping and weight reduction I'd do manually - I hand machine bronze, aluminum and wood archer's thumb-rings, so can wangle…

Find a hobby machinist. People who aren't trying to expand their business don't want to deal in non-gravy projects from customers who don't seem likely to shovel them a bunch of gravy projects later. Machining is a slowly dying industry in the west so there's far more people not growing their business at any one time.

Thanks for the insight. I think you're correct... My area is very gravy oriented in general.
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