I’ve recently been exploring engraving cylindrical objects.
As a placeholder, we could acquire a rotary table. It essentially replaces the Y axis as a rotation instead, thus allowing full engraving to be done on various objects.
I’m hoping that a friend of mine will throw some money into the space for some glasses to be engraved. If you’re also interested, any donations you want to add to get one would be much appreciated!
Definitely interested. Very impressed with the sample on Friday. Could you upload a image of the non-rotary glass test.
My name is 85% at 200mm/s. The logo, 180mm/s.
I went as far as 160mm/s but the glass ‘cratered’, and the finish wasn’t as nice. I think 180mm/s was the sweet spot.
The logo is quite small so the variance across the surface’s curvature is around +/- 2mm. The effects are hardly noticeable, but certainly are there in the right light.
The rotory axis that came with your laser cutter is still at Richmond Makerlabs - I can investigate if the original owner of your machine wants to part with it?
Yes please - that would be amazing. I haven’t looked into it much further than this thread as I’m on a business trip, but could always pop back up to Richmond if needed!
Thanks for spotting this thread
Yes definitely interested. If it’s available that would be brilliant.
We now own one of these after a sneaky deal appeared on eBay. It has been delivered but requires some assembly to get it to work with our machine, but shouldn’t be too much effort.
@TeacherPriest has pledged £20
@Heather (or is that @Heather_Gilligan ) has given me £10
@AndrewPatience were you still interested in throwing in some money?
@Jagmills I’ll chip £20 in too (unless that puts you into profit territory in which case it will be £10 here and £10 for the soldering station )
Thanks for the offer @florian, I wanted to contribute to the axis too - so if you wanted to split between the two things that would be fab!
Yes I’m still interested in putting in £20. I’m happy for that to go to kit for installing it or test samples like below.
https://www.wilko.com/en-uk/wilko-functional-hi-ball-glasses-4pk/p/0239391 (25p each is not too bad to test and demo samples)
I did some preliminary tests on Friday, really pleased with the results so far. Here’s the cliff notes:
- Plugging in the rotary axis is a doddle. Originally I thought I would have to do a lot of rewiring; however, there is a connector that allows disconnection of the laser’s Y axis and connection of the rotary. It worked straight away (woo).
- The table doesn’t quite fit in properly, due to the alignment stops on the existing bed. That’s fine, we have some ideas of how to address this.
- As expected, the rotary axis doesn’t have the same steps per mm as the normal laser axes. That means that some reconfiguration is needed when using the rotary axis - either some scalar % to your design, or configuration in RDWorks.
I need to write a guide on how to use it. This may be the start of the space wiki returning
Excellent. Unless the laws of geometry have changed the steps per mm is going to vary with the diameter of the object being worked on, so we’ll need to work out a conversion equation / chart.
If my memory is holding then the circumference should = d * Pi, so at least it should be a linear relationship (I think).
Yes you’re completely right. My brain was a bit melted and assumed it was gear like and was irrelevant, obviously that was wrong.
Interestingly RDWorks has a fairly hidden setting for this kind of thing as referenced by a few forums - however, it is labelled “NOT IMPLEMENTED” in my copy, but it still seems to do something! It looks like it takes the diameter as a parameter.
It’s early in the day, so I hope I have this correct
I think the wrinkle here is that the object under rotation is being driven at its circumference not its centre. So one step of the rotary axis gearing produces a constant amount of linear movement at the circumference of the, for instance, glass.
Oops, I hadn’t realised that - It’s almost like someone thought about this stuff when they designed it