Instrument maker

[Grambot]

Routers can make a huge mess, that can be difficult to contain at times

Good point Gerry, so I'd also need an enclosure, for mess and sound

Nearly impossible to answer accurately because don't know your skill level and how well equiped you are

My skill/experience is zero, but I'm a good learner when it comes to making things.

My worry is that a) it may take me too long figuring out how to make a machine when I want to get on with using it, and b) when I do make it, as its my first attempt, I may make mistakes, resulting in loss of accuracy.

I think I'm going to ask someone to make a decent machine for me!

[mekanik]

Hi
There is a wealth of information on the forum in the build logs, and the guys will help out with any problems but in your situation it could be prudent to have one designed and built by one of our forum members (if not snowed under) Just place a request in the FREELANCE JOBS AND REQUESTS section and someone might be a able to help.
Rergards
Mike

[Boyan Silyavski]

My last advice before you jump in ordering a machine is have in mind the following:

That below will be your main tool/s in this kind of job/ there are cheaper variants, dont worry but i am speaking about the size here/





So start backwards from there. What spindle you need for that bit, what speeds the machine to move, how will evacuate the chips produced and so on.

Download HSMAdvisor, It has trial though i greatly advise to buy it, as it starts to become indispensable tool for me and if one knows how to use it it will save a lot of money, even when designing a machine. After my recommendation now there are all the chinese water cooled spindles included there. So choose 2.2 and 3kw spindles there, input the above router bit and start playing around so you see what happens. Change machine max achievable speed and so on.

That's how you will make really educated decision on spindle size, machine max speed, rigidity, motors and so on. Knowing exactly what final purpose is, how good a machine could be and how much will cost you that. Find the acceptable point that all is valid and seems good and that's it.


But i will tell you one thing from recent experience: Its good to have a very capable machine even if you don't know how to use it at first. Cause when you learn, there will be nothing to hold you back. Same with music. Any teacher will tell you to buy the best instrument that you could afford.

[Grambot]

Yes, I agree, I want a machine which would enable me to grow in the future, and experiment with new designs. And I'm impressed by just how strong your machine looks!



You said in the description that it achieves 0.1-0.3mm accuracy - is that good for a DIY machine? I would really need no more than 0.1mm, because the parts I'm making are so small and complex, and often, several parts need to fit together in a moving mechanism. The more accurate they are, the better the finished instrument.

I'll have a look at HSMAdvisor, thanks for the link

[Boyan Silyavski]

It achieves 0.01mm not 0.1mm . But without too much over complicating stuff for you i will say that this machine is good for 0.05mm precision jobs or better.


Wood will change its size immediately after the cut, if there is humidity change or similar. Wood is not ideal, even when i cut it to 0.01 now on the machine, its has some flaws that need sanding and polishing, so final piece of only perfect material could be brought to such tolerances. Dont bother about that, we talk here about plastic and aluminum, when we say values under 0.0x

[Boyan Silyavski]

Here is an example. I work mainly with pine. No hard woods in my case, but otherwise some of them really hold that 0.01 precision after machining and can be machined to almost perfect finish.

On a slow machine that below / roughly 200mm diameter, 18mm thick overall/ could take 15-20 min to machine. As you not thickness is exactly 6.5mm.






But later it will need sanding, otherwise i could have machined it straight to 6mm from the beginning but it would have taken a lot of time to almost same finish as sanding it for just 1-2 minutes . So not worth machining it too much. As sanding it is much faster.


So as you see it needs sanding, otherwise i should have wasted unnecessary time to change bits, slow the speed and so on.




But too fast is also bad. As the machine does not have problem to make it for 4 minutes but many pieces chip:



So a compromise time of 6 min. Where i offset profiling toolpath 5mm. So if it chips like picture above its no problem. Then i make another profiling toolpath that takes the last 5mm only. 1.5 min more, but its worth.

Even so, i leave extra 1mm because finnish is not perfect and when 2 pieces glued together and dry, then i take out the last 1mm on the sanding disk, where it takes mere 30 second using 60 grit.




So i could finish this perfectly from the beginning but i will have to tool change, use always sharp bits, use expensive bits. Now i use one bit for 100 pieces then sharpen it by hand using diamond plate. And sand paper finish.

But that said, just yesterday i spend 100 euro on a CMT exchangeable blades bit, which i will use only for finishing, so maybe i will take one operation out, from what i am doing now.



This is just an example. Hard woods as i said could be finished too a much perfect finish, but sometimes a compromise here and there should be made, depends what how much costs you. BUt to warn you from now that even on the best 3d job, after that you have to sand a lot by hand :-) to make it to a high standard

[Ger21]

Good point Gerry, so I'd also need an enclosure, for mess and sound

Don't count on the enclosure to contain the chips. If you don't remove them at the source, and let them build up in the enclosure, they will cause issues with your screws and bearings, which you want to keep clean.

[Grambot]

It achieves 0.01mm not 0.1mm

Oh yes, I misread that, that's much better!

I'm really looking forward to trying out different speeds etc, until I find something that works for me...

Don't count on the enclosure to contain the chips. If you don't remove them at the source, and let them build up in the enclosure, they will cause issues with your screws and bearings, which you want to keep clean

So, what exactly should I have on my list? An enclosure with ventilation, an extraction system, a stand, a selection of bits, and the actual machine?

[JAZZCNC]

Don't count on the enclosure to contain the chips. If you don't remove them at the source, and let them build up in the enclosure, they will cause issues with your screws and bearings, which you want to keep clean.

The other thing to bare in mind with dust extraction/enclosure is the noise.? The noise of the Vaccum will defeat the point of the enclosure.!!
Often they are much noiser than the machine doing the cutting.

Also with being enclosed you need to be aware of the danger Static electricty and fine dust. Together they can be quite dangerous.