If this guy is wanting mainly to do 3D work then I'd also look to make the Front Z axis plate the narrowest and lightest you can make it.
Keep the Y axis bearing spacing wide but bring the Z rails in the most you can get away with and have light narrow front plate.
3D requires fast directional changes and high acceleration so anything to help here will speed up the job.!
Regards the motor access you have enough width and height in that plate to cut an access hole for motor and still not lose any strength, will cut weight too.! . . .Win win.!!
I finished with a 130mm wide fron z plate. It should be enough. I dont believe it can compromise anything, as in my router i have exactly this plate using only one slide with the wide flat rail+ 2 bearing blocks and is ok strong. However i would not like do it like this in this build, cause later i have to play a lot with hole placements and finding screws that could fit under the plate and then aligning it. As i did with mine.
I have another question. When laser cutting, should i do exact holes that hold the plates to the bearing blocks or i should elongate them. Cause how do i know that the rotating nut will fit exactly at that place. Otherwise i will loose some millimeters from the travel. How it is done?
today worked more on the drawings, mostly lightening things where possible without compromising strength. Starts to look like a cheese. However all holes will be closed with bolted light plastic plates so at the end will be quite dustproof even if its not seen on the drawing.
Received the spindle mount brackets. And made an important decision.
Well the 2 brackets are very nice, especially for the money, but... not the same as on the sellers picture. In fact they are so robust that i will use only one. man, they are big.
The important decision is that until i don't have the ball screws and the Hiwin rails at hand Not to order and laser cut pieces and not do any soldering at all. My design heavily depends on the exact hole placement and the laser cut pieces, because i have at hand a very cheap laser service, so cheap that it would be more costly to than to draw by myself and drill the holes at home from junk steel plate with my flimsy drill. And as i don't have a mill at hand and the service here in Spain is very expensive, laser cut is the way for me. Which gives me quite a freedom in my design.
I need some help with the following because i have no idea at all:
1. Proximity sensors
Ok, i designed a plates for them, there is like 12mmm possibility for adjustment. Will solder the plates /10mm thick/ directly on their places. But..
-How far from the actual x,y,z hard stop ???? / x = moves the z , y=moves the gantry/
-any example of Z proximity switch placement? No idea still how and where to fix them. Of importance is the diode to be visible.
-Homing of the z is up, yes?
2. Drag Cable Chain
The thing still missing from the drawings.
-Judging from my current setup/2 small chains one next to another/ i need 20x50 internal drag cable chain so cooling hoses and cables can pass freely. But... i can not find anywhere what is the radius. Grrrrrrrrr. If somebody has a similar chain and point me to the radius i would be very grateful
3. Motor cables
can somebody point me to per/m good motor cable, shielded, here in EU?
It seems also for the purpose of the chain, i have to lift the machine. Another thing is that i still have not found a good case for the electronics. It has to look really good.
I am starting to thing about raising everything and boxing the electronics inside the machine. I have my small machine at home like this, so i know the all bad points and will avoid them. Believe me there are many. Like when drivers heating from inside, heats my aluminum table that heats the hot glue i use for fixing stuff and everything flows in the air some times when routing... Of course knowing them i can avoid them. By the way vibrations to the components was only once a problem and it revealed a cold weld on the BOB transformer. Nothing more...
Waiting for the square rails and ballscrews purchace, made me play again with the design. Decided to stuff all the electronics inside the body. Due to various reasons like avoiding
10 Neutric connectors sticking out at the back, cables, enclosure and so on. mainly because i live at the seaside so connections always give me trouble and i have to glue my connections with hot glue.
Decided also to make the structure from 60x60 4mm at the important places and 3mm at the no so important. But what ever i did i couldn't figure placing diagonals so i finished with rigid square design and 100kg structure. more or less 18meters of steel. I think i overbuild it a bit.
Another decision was to make the bed deep enough so there is no need to change spindle position. Instead a wood bed would be fitted so the spindle works at normal position and only when necessary to remove the wood bed, not move the bed of the machine or anything.
Hope that structure is strong enough, cause tomorrow will order the steel.
If somebody sees something wrong, please tell me until is time, he he.
Everything ordered including the steel for the structure. Still have not ordered the laser cut parts. Untill i have the rails and ball screws at hand.
And here comes the first major problem. The place where i found the 140x80 profile for the gantry refuses to sell me 1m even they have promised me before. . Now i have to buy 6m , or change the design.
At the other place where i would buy the rest of the steel, i found some pieces of 100x100x4 box profile. And generally they will sell me everything cheaper and help me in their machine shop. So now i am contemplating soldering 2 pieces of 100x100 and making the gantry 100x200mm. That would change the design of the gantry widening 2cm, one at each side and making it higher by 6 cm.
What is your opinion about this change? The ball screws will be further 2 cm from the z plate. And the upper bearing slides and rail will go 6 cm higher.
No body says nothing, may be the thread is not so interesting as it seems to me or i am doing it right
Soon will make it more interesting with pictures of the process. Now everything is ordered including the steel profile. Will have to pick it tomorrow and solder it this weekend.
At the end i used only 100x100x3mm steel box for everything. The 4mm seemed very heavy and overkill for the 0.8kw spindle .
I still have doubts for the threads on the rails so most possibly will solder additional plates for the threads of the rails. Anyways they will be covered by epoxy.
Here is the final design , its lighter and stronger than the 60x60x4 and also another point is that less cutting and soldering is needed.
400x1000 x Z 170/up to 200/ working area, gantry ~35-40kg with everything mounted, profile structure and gantry with plates = ~ 100kg
This provoked my first post here...
I'm in the middle of my own build (quite similar to yours) and I'm using 100x100x10 so I'd throw in a few words... Don't overlook the edge radius of your SHS. I got unpleasantly surprised when I was supplied with 100x100 SHS that has 35mm (or perhaps even more) diameter at edges... I was counting with 25mm diameter I found in tables of SHS somewhere but the supplied steel was cold rolled with much larger edge radius. My rails will be right at the edge of square so I added thick plate on top of SHS to support the rails. You may not have this problem with 3mm wall but I'd check at the supplier and verify the design with that in mind.
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