Stell frame cnc 1500X1000. Adjustable table your opinion please

[ba99297]

Here is my progress the last two days.
Yesterday all the day pass drilling and taping the bed and the table for attaching the bed
Attachment 12913
Attachment 12914



And that is how i end up today



No time to write. It is too late... Sorry
Tomorrow

Thanks


Vagelis

[ba99297]

Today progress
I have to weld the upper 80X80 pieces ( where the rails will rest )
The lower pieces ( over the foots) make i little curve ( nearly 5-6mm ) at the middle as reult of the heating.
So i decided to weld 4 spacers at the corners. Put the upper pieces with spot welding after make everything square and parallel as possible
Here we are
Four spacers 120mm at the corners


Then i put the upper pieces and before i spot weld i try to make everything square. I use the 1160mm pieces (this is th excact distanse that the upper 80X80 pieces should have) that i will use for the gantry, and other parts of the cutting bed to make everything parallel



After having the tubes as parallel as possible i messure the excact distnace and cut the rest of the spacers. Then i spot weld from the middle to the corners. After everything was in place i start to full weld the table. In order to avoid too much heat i make 2-3 cm welds at a time from one spacer to the other and from the on side to the opposite. So i pass along the table 20-55 times( welding and cleaning the welds). In order to have better welding results i rise the table to have better angle

End of the day and after turning the table upside down to full weld all the sides, i think the result is more than acceptable

0.0-0.1 radius ( messured at different spots) the offset between the upper rails and the vertical pieces.
This offset will be zero after epoxy ( ...i hope so )


Next step is to make the tuning foots. That is why i weld a 80mm piece at every leg with a hole in the middle to pass the m18 bolt.

Then the epoxy method will take place

Till now i think it must be nearly 200 kgr. The winch save me from a lot of work
Thansk for your comments
P.s Do you think that the legs should be connected at the lower part of the table?

Vagelis

[EddyCurrent]

Looking good, I think the legs are okay as they are. Make sure you paint the frame before doing the epoxy, it's a lot easier, but leave just the top surface of the upper rails bare metal so the epoxy sticks good.

[Boyan Silyavski]

Starts to look very impressive. Nice job. I envy you for your big and nice looking workshop.


-In my opinion you don't need to adjust the table by bolts. The machine needs to be sturdy at earth level. I plan to buy for mine 6 hockey plucks. That's what my friend did and works like a charm. Not needed, but he is a maniac.


-if you follow what Eddy said and paint it, may be don't paint also where the ball screw end supports will be. When the gantry is mounted, then fix the ball screw, then go to one end and then tack solder the fixture for the end support, then go at the other end and repeat. Then remove the ball screw and then solder it carefully there. So when all is ready in the same manner you rectify the ball screws. Cause if you solder now, later may be there would be need to re drill the holes and waste a lot of effort. That's my way of course.

[ba99297]

Thanks both for your valuable advices.
Syliavski when you say NOT to adjust the table by bolts, what if there is any imperfection 1cm at the floor ? The hockey plucks that you suggest will be welded at the frame. What material are made of these plucks?
When you are talking about the balscrew fixture end support, you are talking about X axis? If you see my plans i am going to attach the fixture to the frame with bolt so it will be adjustable.
As for my work shop thanks for your comments. There is my paradise. Music, creation, and no one to bother me.

[EddyCurrent]

As for my work shop thanks for your comments. There is my paradise. Music, creation, and no one to bother me.

Nice, where I am it's mostly pissing down with rain.

[Boyan Silyavski]

I bought M25 or so bolts for the machine, soldered the nuts to the legs, thinking that will hold. When the machine was ready i left it on the nuts only and they lay on the hockey pucks. cause i did not find M25 bolts sturdy enough. On your machine M25 6cm bolt on the legs will shake like a plastic, once that heavy gantry starts accelerating.

The pucks are made from hard PU rubber. make sure they are the solid ones, not refilled with something.


You call 1cm imperfection , i have to deal with 6-7 cm inclination in my garage and i plan to level it with cement. Thats what is best to do, to level the floor under the machine. If i had to deal with 1cm, i would simply stick 10mm steel plate below the leg.


Translate for you design:
I meant these pieces in blue Not to be welded until the gantry is ready and mounted and rectified in all directions:



Then bolt these 2 together with a piece of paper between them/that for the later paint thickness



Then bolt all that is in blue together as it would be at the end, trying all bolts to be in the center of the holes. the bolts must not be tightened very much



Now move to one end the gantry and spot weld with 5- 6 spots 1 of the pieces in blue from the first picture. Rotate by hand the screw and move to other end of machine. Now you spot weld the other fixture.

then dismount all in blue, ballscrews , etc. Then weld well the 2 fixtures. No everything is in parallel/guide rails and ball screws/ and perpendicular/ball screw supports.

When painted and ready, mount them the same way. So the only necessary adjustment will me made by the play of the bolts that hold the ball screw end supports to the fixtures. Tighten them when gantry is at that end.

In other words, now all 2 rails and 2 ballscrews are exactly parallel and have exactly same travel. Doesn't matter if one is up or down, otherwise using other method that also should be taken care of.