Quite an Unusual one

[JAZZCNC]

So basically i will not use DTI until the moment i have the machine running. from experience it seems i can notice with naked eyes 0.05mm gaps without problem against the straight edge/ the epoxy story/ so i am happy that everything is tight fit.

Now now Boyan.!!! . . You contradict your self about lieing to one's self here with this statement.!! . . . . Your fooling your self if you think you can see "Five one hundreth's Gaps" with naked eye over the length or width of this machine.

Not saying your machine isn't or won't be accurate because I know it will or you will make it so. But I must say think your going to be surprised when time comes to cutting just how far out of Tram that spindle will be if you don't put a DTI on it. I also think it will be Bitch to setup looking at the pics.!!

[Boyan Silyavski]

What i meant was i can spot the 0.05-0,1 mm gap between a straight edge and something, say rail or other flat surface. Not that i can spot if the machine is straight or not over all its length or width. I spent a week just making sure the long rails are mounted straight and flat, not counting the epoxy.



Yeah, without DTI its difficult to say more.


What do you mean to tram the spindle? Its trammed already using 2m straight edge and squares. There will be no more tramming until the moment i cut some square aluminum shapes and first i make sure the gantry is squared by the limit switches and later do some stuff and see if there is something off judging by the final dimensions of the work.

Then the bed would be surfaced or head trammed first, but only if i am off by a great deal, depends on what results tell me. It is very easy in fact to tram it all as i always followed your advice of adjust ability making all through holes bigger.

Now about the DTI. I could clamp it now on one side rail and move the head assembly up down and see what DTI says but ... ok i went and clamped it. It says nothing, i mean i mounted all very well only using the squares and edge. Unbelievable but true.

I will power the whole thing then check and readjust if necessary, cause its very difficult to move all by hand. long distances i mean and i get bored.

At the end even if vertically is off with 0.1mm on 200mm travel/ which is not the case/, this is nothing. on 20mm aluminum sheet the inclination would be 200/20=10, so 0.01/10=0.01mm

[JAZZCNC]

You will tell instantly if the spindle is trammed correctly or not when you surface material with a wide cutter. If off then you'll get steps and it doesn't take much error to get steps. The pictures make it look difficult to get at bolts if shimming is needed etc.

[Boyan Silyavski]

Now comes one of the last parts. I frankly admit i was quite indecisive there, from the beginning of the design. So it was time to sit on my arse and make some calculations and think the things clearly.

The working area / table bed. May be it a theme for a whole new topic. i see many people are wondering how to do it differently than plywood, especially if they mean to cut aluminum and cool it.

Now lets be clear i am not talking about the machine bed structure nor the sacrificial board. I am talking about the working bed/fixing area and method which is in between the frame and the sacrificial board and which is water/coolant resistant and is strong enough for moderate aluminum milling

So lets see the options. prices are Spanish, but may be more or less the relations will keep in different countries. Some thickness prices are not known but can be extrapolated. 1kg of steel is ~1 euro, 1kg of aluminum 6082 is ~5euro,

-phenolic 10mm thick 65euro/m2 so as i see it needs to be minimum 20mm best 30mm thick ...
-marine ply wood 15mm thick ~36-50 euro per m2 , i see it needs to be at least 30mm thick.. so its good for a spoil board but expensive for top
-marine ply wood with phenolic top for truck flooring, now this is a good one, but its even more expensive and the phenolic will be very thin to surface

Now instead of writing here i have made some drawing with data for the better options:












I have spent all morning in calculation and last days rethinking the things. So for me its clear:

My choice will be UPN140. I have the bed clearance for it. It is cheap and very strong for the money. Like the last photo, 2 welded together, with T channel and DIY Tee nuts as per drawing. So i will drill a lot of holes and use them for fixture and big sheets will be fixed with clamps that will pass trough the channels. It will be screwed to the table with nuts that pass between the connection of 2 of the UPN. I will have to find a resistance welder from somewhere for clean job.



Note: Moment of inertia is x axis cause its in C position when measures are given, so a bit misleading. Anyway, its in the good for us direction.

last thing that i have not clear is if i will machine it both sides and machine the bed bellow, so all is flat when mounted and dismounted if needed. I am seriously starting to think to somehow mount a grinder on the Z or surface all using small bit, slow speed and coolant. i said before no steel work with that machine, but its quite tempting. And from what i have seen people have done it with much weaker designs.

One thing i know is that on top of that UPN140 i will use then thin phenolic sheet or even better scrap pieces, for sacrificial board. At leats on some part of the machine. On other i will use cheap expanded PVC sheet.

I hope that these calculations money/material/ strength will help people to evaluate properly what exactly bed they need.

Notes
-UPN profile can be cast filled with cement which will make things even better. Non crack cement for table tops and garage floors is enough for that.
-aluminum T channels are damn expensive so i did not even consider them. Even steel channels are very expensive, crazy.


PS2.
One question . For the the threaded holes to be closed to keep them clean , what is the name of the screw that is like a grub screw but is for flat screw driver?

[toomast]

PS2.
One question . For the the threaded holes to be closed to keep them clean , what is the name of the screw that is like a grub screw but is for flat screw driver?

I believe it is called SLOTTED GRUB SCREW.

[Boyan Silyavski]

OK. Some development.

Did i tell you that i plan to add plasma to the machine. Front half for machining, back half of table for plasma. Or whatever life commands,

I know, old China HF plasma no good, combined machines no good... I can say yes, shoot 2500 euro and tomorrow a brand new Hypertherm Powermax 45 will be at my door.

First i have to know if that will pay off where i live, for what i do and so on. However instead i decided to start with what i have at hand, slowly make my way around. I did not skip the THC though as i believe it will be extremely important especially on a combined CNC table like mine.

I did my research and decided to go with the Neuron THC. I skipped the simple THCs where there were no advanced controls. Vietnamese and similar were out of question due to lack of support or support in some strange language.

The ones who are into plasma cutting know the choice is not so big money wise and feature wise. Razordance THC is only for Hypertherm, then there is the Proma, mini THC that looked promising, Cadcnc and Neuron. Or you pay big dollar. Cadcnc and Neuron seemed the most advanced. I as many times at the point of buying something from Cadcnc but the fact that he is in USA, his stuff works bundled together, some of his ridiculous policies mad em not do it. So the Neuron it was.

I will make a separate review when all is working, but i would say the documentation and the support from Andrey till now is outstanding. And to tell you the truth that the most important thing when you start doing something that you do for first time and you don't know nothing about.

So the Neuron THC lite came at home after customs delay /Russia is not EU you know /.

Thats the Plasma, tig, arc. German controlled Chinese machine with 5 year warranty.



First thing i changed the cover screws cause i decided i would open it quite frequently :-)



Then i twisted some pairs of wire for the voltage divider /1mm2 >600v wire, as per recommendation of Neuron manufacturer / :





Then i blowed the dust of the insides, by the way on the box says to do that 2 times per month


Here is my DIY drier for the plasma, painting and for blowing dust. No body would want to blow some drops of water on electronics, right. 10" filter box and 1/2kg of desiccant. Black plastic tube in the middle with a lot of holes so air can pass. On the right is a last stage lubricator outlet for air tools. Thre dry air outlet is in the middle



The insides, with the Neuron mounted, arc ok mounted , RJ45 ethernet communication cable. meanwhile i bout and learned to use cable connector making tools. as it seems Ethernet is the future.



The shed in front of the garage, the welding table and the machine bed arrived. I alsmost finished all till today, though run out of gas, otherwise i would have been welding right now. Will take more pictures when ready. the rage saw cut the UPN 140 like a charm. I was for worried for a moment when all arrived cause i forgot to check if the saw could do that wide



i need a welding table to make my welding table, isnt that funny

[D.C.]

OK. Some development.
Will take more pictures when ready. the rage saw cut the UPN 140 like a charm. I was for worried for a moment when all arrived cause i forgot to check if the saw could do that wide

Amazing build Boyan, those rage saws are quite the beast aren't they.

Do you have an update and more pics of how the build is progressing, this has got to be one of the best build logs I've seen, it would be shame for it to stop before we get some video of the finished thing in action!