Actually Building the Machine!

[Nena]

An example of what i ment with the above message. (Dont bent me on the coords and the drawing, its only an example to get an idear!)

90 Degrees example

45 Degrees example

0 Degrees example

 

[vonG]

Ah, now I get it.
So either the cutting head and dopstick is to big or the linear guides are to short, and the simple solution is to have longer linear guides.

You sure there are no guides that are 20mm wide and over 450mm long? Found several on eBay when I searched for it, but they might not be up to you class.

What is the exact description of the guides?

 

[Nena]

Hi Thomas,

I think just over the 500mm will do 20mm wide and from Rexroth would be perfect. It must be the same type as i showed you before. I couldnt find those larger then 450mm. Im also searching for those, already found one guide from 1070mm so i can cut it in two, and it has 6 guide cars. I offerd him 165 euro's for the guides but im still waiting, so if i see others mayby cheaper ill buy them!

Greets,

Christian

 

[vonG]

I had a thought.
How do you plan to move the faceting head into a different location on the lap when you polish the gem? I mean if the head is in max or min already like in your pictures, then there is no room for changing the heads position on the lap? You cant use the same location (+-y axis) on the lap all the time, it will wear the lap down on just that place. You cant use the whole y-axis length either, then you will get different directions on the lap when passing the middle.
A second axis on the gantry would fix this problem, making it a 5 axis machine. But I think you said something about it being harder to code the software.

When polishing there will always be some errors that need to be fixed by moving the gem in different direction on the lap or to a different location. Like the orange peel effect (wavy pattern on the facets) or small cuts from the prepolish.

 

[thegoldman24]

lm looking forward to seeing this monstrosity up and working hopefully within my lifetime.

 

[Nena]

The linear guide need to be that long it can reach the complete lap in length. So i dont need an z or a 5th axis. If i do it this way i will use the complete lap. But im not able to make a bow movement. We shall see how that is going to work. Just buyed some other things for controlling the machine. Buyed a new computer for the machine, a new parallel port pci and a dvd drive to install my windows 7 ultimate. Im also searching for an rittal cabinet to place all electronics in it. And still waiting and searching for a linear guide. Hopefully the sensors will come this week or the next.

Software that im going to use for the machine:

Windows 7 Ultimate
Apache
Ftp Server
Active Perl
PHP
MySQL

2 Simple Logic Boards for the steppers from Wantai these cards are normaly used for mach3 but these have optocouplers for the outputs and the ports are straight from pc to the motor.

I think i also order the USB IO board UIO-333 from Iknowvations.in but i first want to look if i can controll the stepper with my parallel port. I need to pulse these at around 200khz. Ill hope its going to work.

And again sold for over the 700 euro's again! But i also need to buy a new coil for my XP Deus... but i can search soon in the water when it is getting a bit warmer! +/- 22 Degrees

 

[vonG]

Hope you are right about not needing the z-axis, but Im guessing you know what you are doing anyway.

The bow movement is used to reduce the scratches on the facets, dont think you will need that since you use constant pressure and high precision. As long as you only grind the stone in one direction and lift it from the lap on the way back and only use half the lap, you should be ok. But this you can try out when you have the setup ready and running.

By the way, have you figured out how to apply the right pressure against the lap yet?
Couldnt a 6-axis force/torque sensor be used between the y-axis and the faceting head? Like this one http://www.ati-ia.com/products/ft/sensors.aspx?campaign=ims

 

[Nena]

I dont get problems with the setup i have in mind. But mayby i change the setup to with 90 degrees I still dont have the guides but if i go into the air i go using 25mm guides. The stone will never be at one place at the lap. I checked your link and have found several of those devices but i dont have 1600 euro's for the cheepest! So i need to look for another solution for that one. Ill first try my first solution to this problem of checking sound. Today i spend over 250 euro's for small things like t-nuts, bolts and others... Getting and comming closer! Still didnt draw anything but i almost can go with drawing!

 

[vonG]

I'm not here to put you down or something, even if it sounds like that sometimes. I'm just giving you my opinions and maybe helping you seeing things in another way. Maybe it will help, maybe not.

By one place I meant +-y axis. You can't go all the way from one side to the other on the lap, you will have directional problems on the facets. That's why I said only go half the way on the lap and only in one direction. But I think you will find out that later anyway.

In my opinion it's 1600 well spent. Don't know how much it will or can throw off the precision on the faceting head though. Maybe your way with the sound is better.

Damn those small things cost money, have you bought all bolts and t-nuts you will need now?

What do you have left to draw now?

 

[Nena]

Hmmmzzz I dont get any mails anymore if i post something or get a reply. I dont know if i got everything now, i ordered some 1000 tnuts nut 8 m6 but these are to high but useble for some other things, 200 tnuts 8 m8 for the build 1500 tips for the leads, a bunge of m8 bolts m6 bolts, rings, denn rail, preasure tube 4mm, etc...

hehehe im not thinking down, its only a lot of money, i need to get the machine work not to update the build and never start they are good tips but i need to be a bit realistic with what i spend and first build every thing up now. Otherwise i never build one but it would be a never ending story i want to build the beast and let the motors turn there way

I think i can go draw the complete machine, almost the complete machine, the basic without lap but only the main machine. If i mannage to build it upwards and mayby use an counterweight i can mannage the lap horizontaly. I think ill try this first.

Mayby i can get the guides for 150 and 120 for 8 cars. I even thought about an extra sensor for the y axis. And im thinking in using the 80:1 Harmonic Drive. But first i need to draw it all...

 

[vonG]

Neither do I, must be something wrong with their system or something.

I think the pressure against the lap is the key, as when faceting manually. You can have the best precision and repeatability in the world, but without the same pressure it will never hold when the lap isnt precisely flat. You are right though, about building up the machine first and then go from there.

Did you buy the guides you were bidding on or are you still waiting for the auction to end?

 

[Nena]

Just click Un-Follow Topic and then Follow Topic, worked for me About the preasure, i shall see, i have 58Nm max for preasure and thats way too much but i will see what the results are going to be. I could buy but the best man told me that it where 25mm guides. So i didnt buy those. Even the cars where from aluminium. I dont want those to use, but i have 2 offers open for guides. We shall see again. Did buyed a rittal cabinet for the electronics to keep things as small as posible. 600 x 600 x 210 mm. (100)

Cant wait to start with building and to do some motor/software tests! May i ask you if you started to build what was your budget when building?! How much money would you spend on your machine?!

 

[vonG]

Yes the stone will fly of the dop with that pressure, but if you can go down slowly against the lap and calculate the amount taken of the stone that will not matter. The amount that is taken off the stone will differ for so many reasons though, that it will be hard to calculate.

I had a budget of 10k. But would spend more if needed.

 

[Nena]

We shall see if its going to work, i can always change things later but then i have a machine already running with no preasure anymore to build one 10K is nice im now still under the 2.5k lol but spend a lot more Im now buying all connectors.... almost 100 for only connectors... 40pcs (30) of those Chineese GX16 plugs... 6pcs USB (30) 2pcs RJ45 plugs (20) and some others... All these small things cost a lot. I want to build my cabinet for controlling the machine.

Hehehe its an expensive project but i still like the idear of building one! There arent manny who are building one not the hobbyists anyway...

 

[vonG]

Totally agree with that, it's to expensive for a hobbyist to build one just for their own pleasure. You build one for the possibility to sell the finished gems, not for having the gems sitting in a cabinet at home.

I would focus on things that would make the machine work, so you can try it out. It doesn't have to look good just facet stones that can be sold. Get your money back, then focus on the cosmetics of the machine if needed.

The budget is always the complete cost of the machine. You will probably be over my budget when you are finished building your machine, but I have a more simple structure I guess.

 

[Nena]

Shure i would have gems sitting in a cabinet But i also want to sell gems and go faceting for Class A goldworkers. Its just a chance for me to get to work again and have a nice hobby! In first instance it still is a hobby project Hobby's may cost something LoL

I have counted if i buy all parts new im already over the 40k. But spent now from my own money about 2.500 euro's. And spent by buying and selling about 10k. It takes some time but you can build a good machine for not that much! Its still cheaper than a Facetron Machine!!! Hahahaha

I need someone from the UK who wants to buy some parts for me.... i need 4 connectors from the uk but cant buy them here in the Netherlands...

 

[vonG]

40k is only for the parts, you havent added the programming costs. Thats 4 times my budget, have to sell a lot of stones to cover those costs.
Better to have a machine that works in the end though, so you are doing the right thing and not cutting down on the parts you buy.

Surely there must be someone on this forum that is from the UK and willing to help you.

 

[Nena]

Hi Thomas,

Yes your right, its a heavy costly machine for a hobbyist but it can be done! Just buyed 8 pieces 25mm cars for my Y axis... cant find the 20mm but these are not that wide that it gives problems. 8 pieces 120 Now i need to wait on my offer on several guides 11 of them to be exact hehehe. Im going to use de 80:1 HD and the Y axis is about 640mm. I can almost build everything up now if i got the cars and the guides.

Greets,

Christian

 

[vonG]

Great to hear Christian, hope you get the guides and cars so you can start building.

 

[Nena]

First i need to sell some things again... I'f got a idear to build everything horizontal and that is what ill try first. Hope ill get the guides next week, also my parents will receive about 16 packets from Germany I can build everything up now i thing becourse i already have the type numbers from the guides and cars, so i can download the 3d images from rexroth. Dont know if everything is going to work but thats a problem for later lol!