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WoodKnot
16-06-2021, 11:00 AM
OK, i have decided to open Pandora's box here!

Having had private conversations and online conversations, I am still perplexed at the vast amount of 'seemingly' extremely low quality machines, sold at high end prices that are not fit for purpose?

So, all of these highly successful businesses are selling their kits online to customers across the globe and guess what, they keep selling them. Users are in the main, happy with their purchase, making their little signs and doing what they do.

If the machines were so bad - the online world would not allow this, constant bad reviews and ratings stop poor businesses from operating.

Have you seen all those Youtube builds!! YES!

Have you seen all those Youtube builds complaining of inferior kit NO!

These designs obviously work for the type of things most users want from their home cnc and the few hours per week that they use their machines for.

Then you get the more serious hobbyist that wants to beef up their machine to cut some aluminium plate and more bespoke tweaks and designs are made.

Last you have commercial operators, that are running their machines, in some cases 365 & 24/7.

Huge amounts of investment have been made into these machines and they are deigned and built to work in a commercial environment.

I smiled with amusement when i have read the other threads and any time someone mentions an Openbuild type of machine, it is either immediately put down or not responded to.

Therefore (in my view) the site has become myopic and does not serve the whole cnc community, which is a great shame.

There are obviously some very talented people on this site with multiple skill sets that are a great asset to the community.

Not everyone wants a 1500kg behemoth CNC machine sat in their shed running Lynux and running complex calculations to make a nice valentine's sign for their partner.

Should the site not welcome everyone and help them with their build irrespective of its make or type and encourage people to tweak small elements to improve on basic designs?

WoodKnot

m_c
16-06-2021, 06:24 PM
It's all about expectations, and finding people who actually know what they're talking about and without a vested interest.

Personally, I'm not against people starting with a cheap basic machine, as they give a newbie an idea of how things work, the machines will usually produce a tolerable result, but the machines weaknesses will also show the short comings, and why on this site people are quite critical of any machines flaws.

What I don't like to see are people who spend thousands on a machine, that is quite frankly mediocre.
This is where expectations, experience, and vested interests kick in.
If you've never ran a well designed and built machine before, you're never going to know that continual tweaking to keep things running well isn't a typical thing, or that the cut marks in your parts from machine flex aren't normal. There's also those who know the short comings of their machines, but aren't willing to admit to them.

Youtube is full of people promoting their latest purchases/builds, with lots of inexperienced viewers who don't know any better.
I've seen people claiming their basic machines using v-groove bearings and angle are as good as linear ways. One of those you'll be continually adjusting for maximum performance, the other will just work for thousands of hours without adjustment.
What do you think gets more views, a video with titles like "I built this CNC using basic tools for $500", or "I built this CNC for $5000"?
One of those CNCs will be attempted to be copied far many more than the other, but what one will likely still be running unmodified in 5 years time?

I get that for some people, the continual fettling is part of the hobby, and doing things as cheaply as possible is part of their challenge, but if you expect a cheap design to just work for long period of times without issues, you're going to be quite disappointed. And anybody who tells you otherwise, is at a minimum being economical with the truth and/or oblivious to their machines short comings, or is just an outright liar.

JAZZCNC
16-06-2021, 07:59 PM
OK, i have decided to open Pandora's box here!

You're not opening any box, it's been said before by new users looking at these machines and I can see why you might think as you do. BUT the FACT is things will never change in this respect because the designs are flawed for any kind of serious hobby level usage and no amount of bitching or disbelieving is going to change that.
MC has hit the nail on the head and just reiterated what I said before about many people being unaware of the difference because they don't know any better.!

Both MC and I have been helping people from all around the world on various forums for probably 20yrs now so we have seen a thing or two, so using your Logic wouldn't you think if they were any good we would be using them ourselves or pointing people towards them rather than advising they run away.?

Sadly I think the only way your going to learn is the hard way which is exactly what the experienced and very knowledgeable, not to mention extremely helpful people on this forum try to help new users avoid.!! . . . . . But experience as shown me you just can't help some people and you are looking like one of them.!!

Doddy
17-06-2021, 07:58 AM
You've not yet earned that soapbox.

Woodknot, with the greatest respect, you came here asking advice, and received some good, informed responses, and you are in the process of ignoring much of that learned wisdom and cracking on with your original intent from before your posted. That's your prerogative, go off, buy your machine and come back and join the party. We collectively continue to support and help people no matter what but please don't attack the advice given because it didn't suit your purpose.

By the way, I first posted here trying to improve the performance of a machine I bought off eBay - "British built, superior to Chinese knockoffs" - that I spent a lot of money on before giving up and buying something all together more capable. So I know where you're coming from, I can also guess where you're likely heading to. Crack on - you're answerable only to yourself, or the missus :)

WoodKnot
17-06-2021, 09:14 AM
Doddy, Jazz, M_C

I have rewritten this several times - in an attempt to........ show my appreciation...........whilst ignoring your advice.

Why? - I really don't want some massive CNC machine sat in my workshop, like some huge unmoveable beast.

I have invested a lot of time and money over the years, but i don't want this one bit of kit to take over my whole life and workshop expenditure for the next twelve to eighteen months.

I wanted to add another dimension to my woodworking projects - this damn thing looks like it will take over my life!!

Whilst my good lady wife is understanding, the 'workshop money abyss' is already running on very fine tolerances!

So gents, I am going to make all the mistakes you have mentioned and i apologise for this in advance!

I will regrettably have to change channels, to the land of the poor to mediocre machines to help get this built.

However, with the advice that i have taken already, i will end up with a twin linear ballscrew CNC machine, that will look like a 'superstar' compared to the majority of offerings.

If it turns out to be crap, i will have no problems selling it and will probably make good money on it.

Then, ditch the whole project and go back to the medieval process of hand routing!

Take care gents and thank you

WoodKnot -

Robin Hewitt
17-06-2021, 11:00 AM
I used to say that 200 full steps per rev was fine for 1.7"motors, possibly okay for 2.3" but much too far for 3.4".

I used to suggest that you should use a much smaller motor for the Z axis and buying a set of 3 the same was stupid.

I used to think that buying old XT computers because Bill Gates new software would not let you anywhere near the timer interrupts was a curious solution.

I used to say that cast iron, and lots of it, was the way to go and always had been.

Then I got my granddaughter who taught me humility and had my first mini-stroke which taught me that nothing really matters.

Mind you I still have 2 tons of cast iron in the garage that I play with and have great fun :encouragement:

bestest

Robin

WoodKnot
17-06-2021, 11:13 AM
Good morning Robin

I sincerely hope that you have many, many more years with your granddaughter and enjoying your 2 tonnes of scrap cast iron!!

A very sobering reality for many, take care and thanks

WoodKnot

A_Camera
18-06-2021, 10:55 AM
the site has become myopic and does not serve the whole cnc community, which is a great shame.

Well, I think this site has always been like that. Some members don't seem to understand the difference between hobby and profession. There is a clear difference between between those who MUST have a machine to finance their daily bread, and those who have one because they are interested or want to use one occasionally for some DIY projects. That difference is not seen by those people. They believe that only the best will do, and your machine, as well as mine, is nothing to have. Well, maybe that is the case for them, but for us, a hobby is a hobby, not something which demands the best quality parts or can't be down for maintenance and must run H24/7. The way I see it is that a CNC based on skate bearings, built on MDF plates, using a small DC motor as spindle can give more joy for the users than a huge 1.5 tonne machine gives to these guys. As you say, not everyone needs, wants or even interested in those large machines, we are not necessarily drooling over them, at least not all of us.

Anyway, in my opinion, this forum would benefit from people like you. I think it is interesting to see and read other people's experience and is interesting to see progress in other people's DIY projects. While the high end machine can be cool to watch occasionally, I fin't it more interesting to see amateurs progressing in their projects than perfect machines milling parts I will never mill at a speed I can not even dream about.

Unfortunately, these guys can chase away people like you and me from this forum, unless we are stubborn and keep on staying. On the other hand, without us amateurs, this forum will die, because there isn't much to talk about something which is perfect and everyone has the same opinion. In the end it will become a boring place if everyone leaves and no one is helping with contractive comments those who ask for, or need help. Also the occasional ridiculing comments are counter productive, because it just kills the conversations. Bullying does not help anyone. I think those people should lighten up a little, because they are scaring away other valuable people and contributors. But perhaps that's what they want, I have no idea. Never the less it is sad to see such behaviour.

I did say elsewhere that this hobby is like a black hole. It can swallow everything in terms of money, time and other resources, including our marriage if we are letting it controlled by those guys, or if we always chase perfection and don't set any limits and lose control. Money is not always a subject (at least not in every stage) but never the less, one may not be happy spending a limitless (or very high) amount of money on a hobby. This is nothing they need to consider, it's not their time, not their money, not their marriage.

Anyway, there are some very knowledgable people here, so use their knowledge but filter out what you need and let the other crap pass. After all, it is you who are in control of your actions, and you don't even have to give any motives why you do this or that. Read what they write, learn, but use that the way it suits your needs. Be happy that you receive some answers, far from everyone is that successful every time, so if a discussion starts that's good, even if does not end the same way as you expected. It's their way or no way for some of them, but in the end, that's nonsense, because in the end, you decide which way you go, and I decide which way I go.

Please stay. Believe me, I am not the only one interested in the progress you, and other hobby / DIY people are making. I can see that clearly on the number of views my threads generate, not only here, but also on my YouTube, so while not many people comment (and not always with the words we wish for) it is clear that it is beneficial for the community if we don't just disappear and shut up. I like to see and read about other people's experience and opinions because it opens up my mind and I learn new things or new, different (not necessarily always better) approaches.

You did indeed open a Pandora's box, but if you leave then the lid will be closed again and nothing will improve. If you stay then this site will improve and you will in fact learn and improve as well, but I know how it feels when people ridicule what you are doing and express or insinuate some rude comments. Been there, done that, got the T-shirt... :highly_amused: but in the end, I am glad I stayed, even if the ridiculing is still occasionally ongoing.

Robin Hewitt
18-06-2021, 11:29 AM
On the American sites there is a sort of Guru mentality, you ask your question and await the great man to put you straight. He might be wrong but you are not allowed to question him. Swarms of his acolytes surround you to make sure you toe the line. Americans always want to be told what to do, perhaps teh ones who can think for themselves are in short supply, kept too busy to hang about on forums.

Over here we have the Model Engineering forum where real retired Enginers hang out. They will tell you how to do anything. They know every tool that has ever been available and have opinions on every supplier, past andpresent. There is no point arguing because they are always right. It may be new to you but to them it is stale and boring. They know you won't listen, they know you will fail and come crawling back with your tail between your legs. It is always the same.

On Facebook, YouTube there are some real characters, I spend hours watching, most entertaining.

One of my favorites is the welders. They have a notion that given a picture they can recreate any machine tool from sawn and welded box section. A horde of schoolboys leave encouraging comments as the structure grows. You have to wonder where these impressive irons end up, I cannot believe anyone actually uses them.

Sorry, I become tedious.

Robin

WoodKnot
18-06-2021, 11:52 AM
Thank you A Camera,

I genuinely and sincerely appreciate your comments.

I believe that i am reasonably astute, have a good all round working knowledge of many things, master of none, jack of all trades sort.

I did feel that i was on the wrong site, joined the wrong forum and thought and believe that there are clearly 2 schools of thought.

One leaning heavily to the industrial build type and the other, like me, the hobby guy.

I had decided to stay, to also stay polite whatever was inferred and follow my path, because that's the type of machine I want to build.

It may have issues, issues i may not be able to address and hence my reason for being here.

I do hope that there is a place for everyone and hence me starting the post.

Why should i have to go to an American site? I was really pleased when i stumbled across this site, a UK site!

People talking metric!

All the main woodworking sites are US based and their workshops are bigger than our houses!

So, as an appeal to all, from me, I need help, with my type of build!

I keep apologising for my type of machine, but for many, its a good build and is what they consider to be an advanced build with the Linear rails and bearing blocks. (Whoo!)

No, it won't do a lot of things and i don't think i will ever get passed the 2.5D stage of milling, but that is all I ever aspired to

I love woodworking, its a hobby, an escape.

I want to make some nice signs etc, I don't have the skills to make these with a handheld router and thought i nice little milling machine is a great addition to my workshop.

But it is only that, an addition.

This CNC machine will still end up being the most expensive single piece of kit and in workshop and i have a lot of kit!

Oh, well besides my solid Ash workbench, which i will post a picture of later on.

It cost me £600 just for the timber, but now it's built, probably worth well over 3K - it is rather lovely!!

WoodKnot

WoodKnot
18-06-2021, 12:04 PM
On the American sites there is a sort of Guru mentality, you ask your question and await the great man to put you straight. He might be wrong but you are not allowed to question him. Swarms of his acolytes surround you to make sure you toe the line. Americans always want to be told what to do, perhaps teh ones who can think for themselves are in short supply, kept too busy to hang about on forums.

Over here we have the Model Engineering forum where real retired Enginers hang out. They will tell you how to do anything. They know every tool that has ever been available and have opinions on every supplier, past andpresent. There is no point arguing because they are always right. It may be new to you but to them it is stale and boring. They know you won't listen, they know you will fail and come crawling back with your tail between your legs. It is always the same.

On Facebook, YouTube there are some real characters, I spend hours watching, most entertaining.

One of my favorites is the welders. They have a notion that given a picture they can recreate any machine tool from sawn and welded box section. A horde of schoolboys leave encouraging comments as the structure grows. You have to wonder where these impressive irons end up, I cannot believe anyone actually uses them.

Sorry, I become tedious.

Robin

Thanks Robin

I have to disagree with you though on the Americans, they have some amazing Youtube woodworkers, that take woodworking and carpentry to the next level.

But even the local guys have enormous workshops with kit most UK professional carpenters shops would love to have in their arsenal and most are just hobbyists.

I think the main thing with the Openbuild platform is that nearly all the machines are based on the same platform - extruded aluminium.

To be fair, without adding ball screws and linear rails, there is not that much further that they can take their machines.

Without going to the next level - of the semi industrial type and upwards.

UK engineering has always and always will be some of the best on the planet.

But, I am building a hobby machine and not something that will be cranking out kitchen doors on a production line

WoodKnot

A_Camera
18-06-2021, 12:45 PM
WoodKnot, just keep on posting pictures and messages. Don't let people kick you in the butt because they feel you are not fine enough for their standards. Let them ride on their high horses, who cares...? Some of these guys are really helpful AND have both experience and knowledge, so reading their posts and the comments they make for others can also be rewarding, but sadly, some just have their noses up in the clouds, but that's their problem.

Of course you should not go to the US site just because some people said so, but of course, feel free to be there as well. It is not just their workshops which are bigger, but also their site, for better or worse, there are many more members and many more subjects to discuss and the forum is livelier than here. So actually, even that forum can be used to gain knowledge and get help, especially if the "help" here is total silence or a bunch of negative, wrongly biased off topic comments, which happens more than once here.

Regarding Open Builds, many of them are not even aluminium extrusion based, but plywood and MDF and I think those guys also have great fun with their machines. As long as we know the limitations of our machines and capabilities... My own is also a "toy" based on extrusions, cheap ball screws and so on, however, it is definitely the most expensive (last time I checked was about 3-4k USD and heaviest (over 130kg now) machine I ever owned, but I know that it is VERY capable to do everything I made it for plus a lot more. So extrusions, cheap ball screws and your linear rails will indeed make up a nice machine in the end, I am sure of that. But buying cheap is still a bit of a gambling, though most of the time they are of good enough quality today, unlike 5-10 years ago.

So, good luck and continue.