Stell frame cnc 1500X1000. Adjustable table your opinion please

[Davek0974]

Loads of steel going in, nice:)

Kostas looks like a perfectionist, hard to find in a commercial shop when time is money.

[ba99297]

Hi every body
Wednesday morning I went to a friend of mine who is a wood processing machine constructor, one of the few that manage to survive in the Greek economic environment.


http://www.nikolaidismachines.com/index.php?lang=el

Previous week I gave him my cnc gantry in order to put it in the planer (a 6 metres one), in order to mill it and make a datum surface for the the hiwin rails.


It is possible that the frame (1900mmX1200mm) can be handled from that planer so i have it milled for the x axis rails

This is the Result

Dial indicator has been used for zeroing the piece

After milling the gantry I had to do the drilling and taping
My friend in order to help put the gantry in a drilling and taping mill (the blue color machine 3-4 meters long) so that I could have the threading in a more precise way (other than drilling and taping with hand). This was one of my big nightmares ( how to drill and tap nearly 40 holes on 14mm steel).
He took me no money for that job. I would like to thank him.
First the machine spot the holes

Then Drill and tap



Even after milling the surface is not 100% flat against straight edge
I wouldn’t expect zero level accuracy from a 6 meters long machine
When i put the straight edge against the surface, i can see the light pass through but the 0,02mm filler cant pass . So we are talking aboutan error smaller than 0,02mm.
In order to get the best result i will shim the y axis rails. I remember Deans' word many times. How right he is ? He told me " Vagelis even after epoxy method or milling, it is possible that shims will be need in some spots". I don’t want to use the epoxy method, as i think that shimming is more challenging and of course more difficult.
I will be glad to hear every comment

Here is a video of that day
https://youtu.be/4VUnQhaaJIE

Vagelis

[ba99297]

Some small progress
Last days I have been working on the gantry
As I said even if the gantry has be milled in a six meters planer, there were some small errors that could be corrected with a couple of aluminum foil.
I don’t know if everybody who had some part milled or use the epoxy method has a true flat surface or i am the only one
Even if the error wasn’t so big, i decided to be as accurate as i can with the means that i have (a 1200mm straight edge) and make the rail as flat as possible. I decide to use aluminum foil shims. i have one basic principle in my construction. As this is my first build i want to make secure steps with so that it won’t be needed to come back again. I think that every small error become large as the progress is going on. That is why I use shims even if i had the gantry milled. To be honest the most useful work after having the gantry milled, wasn’t the leveling process but the milling and taping process.


The planer mill 3mm so that there is a datum face for the master rail


The other rail will be adjusted for paralelsim by following the master

I put the rails temporary to get an idea about how it will look like



After shimming the master rail i tighten it to the datum face

Some pictures from the z axis that follows

Tommorrow i will start adjusting the slave rail according the master

Vagelis

[JAZZCNC]

Looking good Vagelis keep it moving along.. .

[komatias]

Pwpw Vaggeli, I had no idea there were such factories in mainland Greece. Do you know if they recondition machines too, or just make their own?

[ba99297]

Yes there were such factories but very few.
I think my friend should be one of the last constructor at that scale here in Macedonia-Greece who manage to survive
As you mention they recondition second hand machines.

[ba99297]

Hi
As I have told I had my gantry milled on a 6 meter planer
The result wasn’t perfect so I had to shim the rails(at some spots) in order to be straight( no light pass) against straight edge.
I had the last three days trying to shim the rails and I think that the result is acceptable
After shimming I try to attach the y axis steel plate (that moves left right)
My question is how tight should be moved. I know that the hiwin carriages have some preload in order to be more accurate.
I made some tests
I use a zero flat ( from surface grinder) steel plate that will be used for my x axis.
I connect to this plate two carriages and put it on the y axis rails
By using a kitchen scale I measure 700gr force for the plate to move
I did the same with the y axis plate( that has been milled in a mill and it is nearly 3 times havier). It needs 2,7 kgr force to move it.
I made a video that show the two plates
First I move the x axis plate (that will be used in x axis), and then the y axis plate
I would like to ask if what you see and what you hear is normal for hiwin carriages
Also if there is any suggestion for grease for the hiwin carriages

P.S amplify your headspeakers
Here is the video

https://youtu.be/yQ5P9gRsEY0


Thanks for your time
Vagelis