slip fall

[Guido]

Hello everyone,

I would like to receive opinions on a phenomenon/problem that is occurring on a device under construction.

a device has been built that can be compared to the sledge of a milling machine (the beam that carries the head milling or the lunettes....of once). in fact the whole is composed of a steel support worked by the full and a sleigh in very robust electro-welded that enters and exits when necessary.
guides placed on the sleigh are made of rectified frame steel while on the fixed bracket was used of the braces and related lards and strips to allow a movement of the sleigh with the minimum game.
the sled carries a load of about 50kg place "on the tip".

When the sleigh is all in, its guides are perfectly parallel to the reference plane, but when it starts to go out I have a very substantial fall of motion more than expected.
In practice, for every 25 mm of output, I have about 0.08 mm of fall that leads to 0.15 (probably due to the effect of the lever) starting from 2/3 stroke.I conducted some checks on the games believing it would depend on this but remain approximately those left to allow the slide (0.02 mm).
I moved to the cad the slope or the max fall with sled all out with the games detected and comes out a fall much lower than the reality therefore I would exclude all responsibility to the load of the game.
I find it unlikely that it can flex the sled given the consistency (flats from 25 mm to form a painting 150x150 and max ledge slip 300 mm. the support is 200 mm long and when the sled is all out of 300 mm it remains all inside the support. 500 mm long slip.
I probably have a series of cheatings that add up cause such fall. I also suspected the crushing of the turquoise but I think it is unlikely.

at the moment I solved by counterbalance the system on 50% of the race but I continue to fall unacceptable at the end of the race or "downs" at zero.

Any experience in this regard?
the big milling machines that have tobogganings that also have 1000 or more as they solve?

Thank you.
guide

 

[MARCO54]

hello to all
My experience brings me to these reflections
1' the presumed piece obtained by welding, before processing
must be "distinct" otherwise welds " pull " as they say in jargon
and the piece does not remain firm
2' I would check if the grinding was done correctly and not forcing the bracket
3' would be good norm that support is as long as running
I explain better running 300-support 300
4' I think with profiled guides and related trolleys you can reduce weight
of the sleigh (in my opinion too much given the section of the dishes used and the weight to bear) and get fallen significantly lower

with regard to the sleighs of the milling machines, seen that the argument has always fascinated me, my ""culture"""" from these answers
1' as the toboggan goes out, it gives him a movimeto uphill acting on
counterweight chains by means of a cylinder that rotates the tobogganing saddle, all regulated by proprtional valves managed by the control
2' divides the exit race and each tot raises the saddle and consequently slip
clearly on numerical control machines
3' As the toboggan goes out, it curves the same with hydraulic rods placed inside it, managed by proportional valves and control, giving it the shape of a banana
4' in fact when the electronics were not so "brave" with tie rods curved the sleds then once rectified they removed and the sledboard assumed the profile "banana" that allowed him during the exit to have a straight trajectory or almost

now that I have told you my life I greet you
Hello everyone

 

[Guido]

Thanks marco,

What you wrote is very interesting.

greetings
guide