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Guerrilla guide to CNC machining, mold making, and resin casting (2015)

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Re: Guerrilla guide to CNC machining, mold making, and resin casting (2015)

#141

Post by karmicthreat »

pyb wrote: post #10
legitster wrote: post #6

Semi-related: As an average consumer I'm disappointed that nearly a decade of the "makerspace" has seemingly failed to produce any sort of meaningful Renaissance in small-scale US manufacturing. I've purchased the odd 3D printed or resin cast tchotchke from small operations a few times at this point. But it's still disappointing that if you need professional quality products, you still either need to pay out the nose…

I also hold this unpopular opinion : the maker movement has ultimately failed. I am not fully certain why, but think social factors are partly to blame. What I saw (in the UK) was that the new generation of middle-class, hobbyist makers weren't interested in engaging with and learning from the historical, working-class manufacturing sector.

Founded one with some others in grand rapids, mi 8+ years ago. From a social perspective it was fantastic. But nobody wanted to pay what was needed to even keep the light on. Very few people were making money out of the space. That is pretty much needed to justify 100$+/mo.

Re: Guerrilla guide to CNC machining, mold making, and resin casting (2015)

#142

Post by Prcmaker »

digdugdirk wrote: post #106
donkeyofd00m wrote: post #95

Earlier quoted context omitted.

Lol sweet... so even you guys with highly dangerous stuff too Hey, my favourite jank tip: an O ring blew but you don't have a replacement? Bubble gum works pretty well for a few days

Okay, but maybe lets not share that particular tip with the dude who works on radiation equipment?

There are stacks of subsystems that can be tested quickly, janky, yet safely. Safety is always paramount, but a relative term. Safe for an end user, and safe for a prototype engineering test need not be comparable. Similar safety, for sure, similar longevity, ease of use etc., potentially very different.

Re: Guerrilla guide to CNC machining, mold making, and resin casting (2015)

#143

Post by hef19898 »

DanTheManPR wrote: post #72
totemandtoken wrote: post #48

Earlier quoted context omitted.

I was a mechanical engineer before I shifted to software development (so kind of the opposite of you) and I think you need actual, full on college level schooling to be a mechanical engineer in most cases. The stuff you're focusing on - basically manufacturing techniques - is a very small part of engineering in general. I didn't see any mention of CAD or FEA work, but even assuming you do know some of that or can acc…

> The biggest difference I see between software developers and mechanical engineers is a way of thinking. I realize that sounds very woo, but it's very obvious to me and to other mechanical engineers I've spoken to. As a fellow trained ME, yes, it seems obvious to me as well. A good school and program will have you spending several years in intensive study and thought about the fundamentals and wider implications of…

Fully agree. Even if I am not a full mechanical engineer I am an industrial one by training. And over half of my studies was equivalent to what the mechanical engineers did as well. And somehow that affects how think about the world and stuff, engineering thinking of sorts.

I am im supply chain management now, and compared to others in thay domain that are really good SCMs but not engineers, thinking like an engineer makes things easier sometimes.

I also agree on using the old hands on the shop floor when it comes to manufacturing and machining parts, engineering / design for manufacturing is something a lot of engineers struggle with. Also goes for maintenance and what not. And the good engineers listen carefully to that kind of feed-backband actually search it. This was one something my profs pointed out to us all the time as being an important part of our future jobs. Obviously, some people are better at that then others.

Re: Guerrilla guide to CNC machining, mold making, and resin casting (2015)

#144

Post by mmaunder »

takk309 wrote: post #139
mmaunder wrote: post #137

I use a Shapeoko XXL 3 and 4 and I have a HDM on the way. The 5 Pro and migration to ballscrews for X and Y instead of belts for their more affordable machines looks great. Wanted to first say this is a great resource and I’ll be constantly referring to it. It doesn’t mention Fusion 360 and Vectric Aspire much so I just wanted to add that Fusion is great for engineering designs and CAM but is terrible at machining sh…

I watched a good video on the subject of adaptive clearing taking too long to calculate and it helped me to improve the processing and machining time of complex geometry. https://youtu.be/osNPQr5-EpM Another thing I found with topographic stuff is to simplify the mesh after importing it. It makes very little difference to the final project depending on your scale.

Makes a big difference in quality in my experience and the conversions generally run overnight. Same applies to M1 architecture and high end gaming PCs. I am for example carving the entire state of Colorado on 24” X 24” oak 2.5 inches deep. But I’ve see the same loss on quality on eg a VW beetle relief that I carved that was 24x12”. Aspire has blown me away with the end result and speed of computation.

Re: Guerrilla guide to CNC machining, mold making, and resin casting (2015)

#145

Post by hef19898 »

bsder wrote: post #107
Animats wrote: post #63

Earlier quoted context omitted.

> Maybe I'll visit a makerspace? Ah, but every one in my area appears to have gone defunct since Covid year zero. Yes. I miss TechShop, where I did CNC machining. It's not all that difficult. Maybe 100-200 hours to minimal competence. What's left of the maker movement seems to have been taken over by little old ladies into crafting. Gluing construction paper and macrame, not machining and welding. Activities classes…

Some makerspaces are still around, for example: Austin, TX: https://asmbly.org/ Worcester, MA: https://technocopia.org/ Irvine, CA: https://urbanworkshop.net/ The problem is that none of them are what I would call "cheap" anymore. > Activities classes for middle schoolers where they assemble kits, not original work. Don't look down on this. Assembling an electronics kit is what got a LOT of us greybeards into electro…

We now have a couple in my city of 300k people, I go for blacksmithing and welding (have to soon to finish something for family that lies there since November...). Or if I need some heavy woodworking machinery, luckily I have quite a bit of smaller machines at home, most of which inheritence of my late grandfather. Time permitting, I like manual work like that, good counterbalance to an otherwise typical office job.

Re: Guerrilla guide to CNC machining, mold making, and resin casting (2015)

#146

Post by jononor »

DalekBaldwin wrote: post #33

As somebody trying to get into mechanical engineering while living in a small urban apartment, this has been an incredible resource... not that I've made much progress along the lines it describes though. It's tough to plan a path toward growth in these skills without sustaining inordinate expenses at each step. I can't afford to become afflicted with Gear Acquisition Syndrome. I've come close to dropping huge sums o…

Whats your goal/motivation? How to proceed would depend a lot on that. Tinkering as a hobby? Making something physical? Understand how things are made? Prototyping an idea for commercialisation? Career change?

Re: Guerrilla guide to CNC machining, mold making, and resin casting (2015)

#147

Post by jononor »

tgsovlerkhgsel wrote: post #65
throwaway4aday wrote: post #8

I think CNC machining is primed for developments that make it much easier to use for the home hobbyist. The tech is very close to what's needed for 3D printing but it has a few added requirements like the need for a sturdier frame and accommodations for a fairly large and powerful motor. Both are solvable with the right materials and the motor can be anything from a DC spindle to a repurposed wood router. The biggest…

One major difference between 3D printing and CNC is that 3D printing is standardized and simple enough that the steps from a 3D model to a printout are mostly automated. The workpiece is held by sticking to the print bed, print paths are autogenerated and layer by layer. With CNC, you have to figure out how to hold the workpiece, often with multiple setups (which have to be done precisely), machining strategy (toolpa…

These are all things that I believe can be improved by better software and machines that are designed to teach people how to do it. Current software is still mostly designed for the experts, assuming a whole lot of knowledge exists from before or is built up separately.

Re: Guerrilla guide to CNC machining, mold making, and resin casting (2015)

#148

Post by jononor »

legitster wrote: post #6

Semi-related: As an average consumer I'm disappointed that nearly a decade of the "makerspace" has seemingly failed to produce any sort of meaningful Renaissance in small-scale US manufacturing. I've purchased the odd 3D printed or resin cast tchotchke from small operations a few times at this point. But it's still disappointing that if you need professional quality products, you still either need to pay out the nose…

What has happened is that services offering medium scales production has become quite a lot more accessible. One can get a quote by uploading to online form, no need to enter a long term supplier agreement, few restrictions on minimum order quantity, and the starting points of prices is lower that before. And the 3d printer is key tool in prototyping the solution, and validating the design before sendibg off. It greatly reduces the risk of spending money manufacturing the wrong thing, or in wrong way (design issues).

Re: Guerrilla guide to CNC machining, mold making, and resin casting (2015)

#149

Post by HWR_14 »

mmaunder wrote: post #138
HWR_14 wrote: post #117

The information there seems to dismiss a lot of the dust considerations with regard to cncing standard (aluminum, wood, plastic) materials. Other sources online have been pretty scary. Does anyone have any experience or knowledge?

Most CNC machines come with a vacuum attachment which I recommend using. If your feeds and speeds are correct your making chips, not dust.

Thanks.

If the CNC machine does not have a vacuum attachment (if it's just a small hobbyist machine) are there best practices? And if it does, is a simple shopvac sufficient or should I be looking at HEPA filters?

Re: Guerrilla guide to CNC machining, mold making, and resin casting (2015)

#150

Post by mmaunder »

HWR_14 wrote: post #149
mmaunder wrote: post #138

Earlier quoted context omitted.

Most CNC machines come with a vacuum attachment which I recommend using. If your feeds and speeds are correct your making chips, not dust.

Thanks. If the CNC machine does not have a vacuum attachment (if it's just a small hobbyist machine) are there best practices? And if it does, is a simple shopvac sufficient or should I be looking at HEPA filters?

I'm sure googling this will help you out. Mine only have vacuum attachments and filters.
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