An other dummy question, but those are the sort of things I get stuck on :)
Does belt length matter if I only go from 10 t in mesh to 11 t in mesh?
Thanks
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An other dummy question, but those are the sort of things I get stuck on :)
Does belt length matter if I only go from 10 t in mesh to 11 t in mesh?
Thanks
All belt tech data is for 6 teeth in mesh.Quote:
Originally Posted by HipoPapi
Matter how? If you mean is 10 t in mesh enough - yes it is. HTD 5m 15mm belt is right in the middle for what we use it so even 6t in mesh is ok.
Sorry I did not make it clear.Quote:
Originally Posted by silyavski
I have got to the Y axes mount and I would have to use a longer belt. Larger center distance. Is that a problem in any way? Like I said I go from 10 t in mash to 11 t in mash.
I am using 25 mm 5 pitch belts.
Thanks
How many teeth you calculate the belt to be long?
I have asked that same question before and seems there is no problem.
But personally i would try all belts to be as short as possible. Actually on the machine i am building now i had to use 1200mm belt at one place /z/ and i worked on and changed the design until my longest belt is 305 mm. Again, its absolutely personal, but i wouldn't use something longer than 350mm.
Thanks Boyan,Quote:
Originally Posted by silyavski
On the X as pictured above at the moment is set for 385 long belts. On the Y I will have to use a 665 long one otherwise I would need to move the servo and belt assembly into a place I dont like as I want to be able to keep my eyes on it and most importantly protect it from the snow.
Thanks for the advice now I know the longer belt isn't a big problem :)
Vass
Where is that place? Did you fit it into the gantry between the beams or at the back in the middle of one of the gantry sides? cause that is where i would fit it.Quote:
Originally Posted by HipoPapi
Sorry for the late reply. I had a serious hiccup with my computer but finally is up and running again. Also I have decided to wait with the laser cut until the linear motion components arrive as I would like to double check some of the measurements.Quote:
Originally Posted by silyavski
Yes I had to mount it on the side of the gantry as otherwise the Z axes would hit the pulley as my Z axes travels from outer gantry side plate to outer side plate.
At the moment I have all the axes designed so they can be geared 3:1 or 2:1 will decide on that later all I had to see at the moment is that in either case the belts wont be hitting any of the mounting screws.
http://www.mycncuk.com/attachment.ph...id=13572&stc=1http://www.mycncuk.com/attachment.ph...id=13573&stc=1
Wouldn't it be better if you make the Z not only for that particular case but to be able to mount a normal tool on the spindle and to reach the bed or near it? I mean what if you decide to do something other than ice block?
Say you decide tomorrow to make a mold for the ice blocks, it must work as a normal machine not only with extra long bits, right?
Quote:
Originally Posted by silyavski
I am intending to use a variety of cutters on the spindle not just this long one. I only have this one always in the spindle because this long bit and the ice block are the things that have defined the dimensions of the machine while designing it as my ice block is always the same size ( I mean this is the maximum size of an ice block that I use ) and the long bit is the one that needs to be able to travel on top of the block.
The Z is designed that the spindle can go down to 6 cm from the table. I dont think I will ever use any smaller ice than that and if I do I would still do the routing on the big block and then cut the finished slice of of it on the band saw because otherwise is way to fragile.
Using the machine for anything other than ice is probably out of the question as the machine will be permanently in a freezer and the freezer filters would get messed up. Also particles from other materials could contaminate the ice blocks in the freezer something I defiantly dont want as they have to be food grade.
I am planning to build a second machine primarily for wood if everything goes to plan with this one.
You have asked me earlier about the servos I am intending to use but than said nothing about them.....any thoughts?
http://www.mycncuk.com/attachment.ph...id=13574&stc=1
http://www.mycncuk.com/attachment.ph...id=13575&stc=1
Now looking at your latest drawing i ask my self the following questions:
Why this design at all? Wouldn't it be better to do it similar to my first build, where the work piece is inside the base structure, the gantry side legs are much shorter and most importantly the linear rails are outside of any dust/snow flakes/ and the ball screw is protected also.
The only possible drawback i could see is evacuation of snow dust. As the work piece is smaller than the table and both sides left and right- half z axis space is present, so you fit below the workpiece a table bed only sized exactlt as the workpiece, that leaves like 15cm holes each side, so you just have to raise the machine via legs so the whole machine have clearance from floor or table such that the snow dust falls there.
What i say is tried and works. Look at my video https://plus.google.com/u/0/photos/r...69713128538019 , only the dark brown plastic is the real bed needed. Light brown can be removed. 2 black plastics at both sides via magnets . As you see even working foam does not make the rails and balls screws dirty.
On your design snow falls on your linear guide, ball screw, ball screw bearings and even motor maybe. I know that your inspirational design is so, but why not make better one.
You are absolutely right in what you are saying Boyan, and at the beginning stages of the design I have thought a lot about raising the sides as it results in a stronger and lighter gantry in fact I have started with the design of the machine you made for your friend.*But protecting the linear motion components was not one of the positive side of that method.I have worked on similar machines earlier and learned a couple of lessons. One ice block can produce as much as 3 wheel barrels of snow which means I have to do some cleaning while the machine is running also one ice block weighs 150 kg so having clear access from all sides is a must. I work mostly by myself and just* to align the block to a line requires quite a bit of hand torque :)* The big block of ice slides smooth and easy after I move it but I also have to stop it and that also requires some force. With raised sides I could also have my hands trapped between the block and sides.*This cac machine is part of larger project I am working on. The ice block gets on to the cnc bed after being plained on a band saw. The carriage that holds the ice block under the band saw is the same hight as the cnc bad and can be rolled in front of the cnc machine so I can slide the block across easier.*I have designed protection for the screws out of acrylic sheet and I hope I will cut it with the machine before going into the*freezer also I have visited zappa automation and seen a couple of samples of the custom made protectors they make and I found those up to the task.*As far as the design goes I think I am going to draw the line and consider it done also the steel frame has already been welded together. The* next step is to to put on the leveling feet do the channels and pour the epoxy for the X. And while waiting for that to dry I order the laser cut pieces and figure out the gearing.*
Dean has done some calculations for me regarding the gearing and he thinks I would be well off with 400 w servos and I am sure his right but when I have all the final details will ask again.
150kg? That explains it all. You are right there.