See the attached screenshot - it’s a large part - In Profile - but not in volume or in slice volumes.
The support raft however is filled in for the entire profile, when I print a part with a support raft that big it causes major issues during the peel on the raft slices.
The slide mechanism slips - making very loud clunking noises as the drive belt slips cog notches, and the whole resin tray jerks and vibrates with each slip. Eventually the slide will work after about 4/5 slips but presumably not before doing some damage to the belt and cog.
Sometimes I can “magically” find an orientation that doesn’t cause the raft to fill in the entire part exterior profile - contrast the first pic with the one below, which prints fine without issues.
Why is the behaviour inconsistent? is there any way to fix it - or do I have to keep playing with orientations, or even manually place all the supports to get a printable raft?
@mgarrity that’s a great tip thanks - but is there any chance of getting preform to be smarter about rafts?
Having just tried this - I’m not sure I can use this method, the support “gap” I have to create ends up leaving bad local minima (there are regular knobs on the underside of the part) and it needs to be printed this way up since the unsupported side is for a mould.
I would angle the part more on the length orientation- as far as you can without getting internal supports on the up side rim… and place the gap on the opposite side than you have. the steeper the angle- the less of an issue you will have with slight red shading as successive layers are not as cantilevered out beyond the prior layers.
Yeah, I’m afraid that trick isn’t going to work if the lower surface has a bunch of bumps. You don’t really have much control over support placement in that case because each of the minimas needs to be supported.
We have talked about adding support for the hole in the middle of big rafts, but that feature isn’t currently scheduled.
I very much agree with your point of view that this not only affects the machine, but also affects the resin slot. The very large contact surface will directly damage the socket of the resin slot. It will break directly. I already have 3 resin slots that are damaged. Only print small thing
The F2 has a peel action ramp from layers 1 thru 20 or so, and it’s not until layer 13 than the separation lift and slide start to integrate. Before layer 13 the separation lift is very very slow, and completes entirely before the slide begins.
So - bases that are 1.2mm thick or less at 100 micron (or are bases always printed at 100 micron now regardless of part resolution?) dont have this problem. Since at layer 13 we no longer have the stiction problem of a large raft.
With the large rafts on the LT tank the separation lift is still quite dramatic with a large thunk and very visible lifting of the resin tray, but if the raft is 1.2mm or thinner at least the slide belt doesn’t slip as well.
