Hi All- Details and more details. The drawings are starting to stack. Peter
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Hi All- Details and more details. The drawings are starting to stack. Peter
Hi All Lurkers - Been away for a couple of days doing some sailing trials on a flying trimaran. Not enough wind to fly but sorted a lot of the boat. Back at the coal face. Have sorted all the assembly drawings and corrected a few part names that I used from old projects. Corrected some part/assm links and made more part dwgs. Now the assemblies are correct, I can get serious at a part level. The paper stack gets reviewed, marked up then next cycle gets corrected and reprinted. Use a lot of paper in this process. When there's no more mark ups its done. Thinking about the motor mounts on the gantry. Probably need to make these a bracket so it can be customised for different machines, I'm sure some people are going to want to use N34's or a ballscrew. So will come to that when I get to the gantry parts. Peter
Looking good.
I'm frequently surprised to see that people buy a quality ballscrew and then mount the stepper motor on the end using long, spindly stand-offs, seemingly unaware that twist in these will screw up the accuracy when the machine is under load. I look forward to seeing your solutions.
Hi Zorbit - Good to know your still out there. Yes some standoffs are very spindly. I have not done any simulation on the motor mounts or returns. So this will be put on the to do list. I've just finished fixing a couple of inconsistent dwgs in the assemblies and I think I'm clear to work on the parts seriously. I organise my axes so they are wisywig to the DRO on UCCNC. The laptop will be to the side of the machine on a small ledge so the Y axis will be the transverse axis (the gantry direction) and the X axis will be the long axis, along the table. So the X axis will have a slave A axis. Just thinking ahead... Peter
On the subject of "thinking ahead", have you considered making it easier to retro-fit a toolchanger ?
Hi Zorbit -Haven't been involved in a tool changer before so don't know exactly what's required. At the "Maker" level ATC's would be rare I think. But if you have a bullet point list of pointers I'm happy to see where it goes. Still working on drawings....Peter
Before the arrival of cheap chinese steppers, people used high quality components, then came with real spec sheets and technical info. These would tell you that a motor should be mounted to a solid plate, preferably aluminum if it was running hot, which would act as a heatsink.Quote:
and then mount the stepper motor on the end using long, spindly stand-offs, seemingly unaware that twist in these will screw up the accuracy when the machine is under load
A stepper should NEVER be mounted on standoffs.
Hi All - Beavering at the dwgs. Added them up, about 100 to do and I've established 19. So about 20% in. By established I mean the dwg exists and is linked into its parent in the database. Then it's easy to change and update via the part or the assembly itself. If the part changes the drawing changes. For instance just checked and changed the hole sizes on one of the bearing brackets to allow a little more clearance, the dwg updated automatically. As I'm establishing drawings I'm checking PCD's, hole sizes and alignments. I'm also noting on the dwg what's important in that part.Once the full set is established I can run through them at a detail level. Cheers Peter
Hi All & Sundry especially Sundry. Still going on the dwgs. If there's 100 to do just clicked over the 30% mark. I'm only doing dgws for the sheet-metal quote. It will take 2 weeks or so for them to get the quotes back. I'll send them out to 3 companies. While its out for quotes then I'll do the other dwgs so it should be all together by the time the main quotes are in. Then I can put the whole shebang together and figure out how much it should cost then adjust parts to the budget. Cheers Peter
Looking great:)
Hi out there - You would think that getting a belt lined up with parts is an easy thing to do with a high powered CAD system? NOT. Once you realise that there are over 10 parts to get right and they are all interbreed, you suddenly find your in a mess. My prior machines used motor and return mounts that were deliberately designed as identical and they had to be set up with the correct gap to the rail. So this issue was a fitting problem not a design problem. On Brevis (prior machine) I tried to design mounts that touched the rail so set up of the offset was automatic. That didn't work out. On Maximus I bent the flange of the mounts outwards so it fays to the rail creating the correct offset. Perfect... makes for an easy fit-up. I then decided to make a spot drilling template so its even easier and in this process found one end was 1.5mm out and the bolt pattern was different at the motor and return ends. So I adjusted the bolt pattern and offset but the belt alignment was still wrong.... going in circles again.. But once I found the magic token it all fell into place and I can get to the next level... So now we have parts that automatically set the belt offset and a spot drilling template that makes life easy for fitting. More hours burned... Back to drawings...Peter