Almost there. everything seems to be working (at least in the shop) . Still some little glitches which we hope to work out between now and our first match this weekend in Mount Olive. Here are some visuals taken last week
Sorry its still a bit of a mess as it includes deprecated items and some tests and the project is still live as there are still changes being made - but if anyone is desperate and needs some inspiration I hope we can help
Forgot some stats. About 14 kg of HIPS printed on 2 Anycubic Chirons, square tubing is 1/2 in aluminum 3/32 wall thickness Motors are either Cim Minis or CIM or Neos Weight almost 80 lb currently without the Battery and Bumpers. 1/8 in aluminum plate at the bottom for a little extra weight and a little bit to tie some 3DP pieces together. We do not extend outside the perimeter of the robot at this time. Drive is tank drive with 2 6 in wheels in the front and 2 6in omnis in the rear for easier turning. Shooter in front, ball pickup in rear.
Really cool robot. I really like the 3D printed parts with aluminum reinforcement. Something 4272 may experiment with in the future.
I was curious what the thought process was to using HIPS. I’ve personally used a lot of PLA, and PETG, but haven’t played with HIPS. What advantages does HIPS offer?
PLA is tensile wise the strongest filament but very brittle and tough to print “solid” that means as close as possible to injection molding as its warping power is great here is a pic of a broken (intentionally) piece to demonstrate the printing solid meaning
PETG is what I would call a semi flex it got a lot of give. Now HIPS is what we call “the better ABS” its much stiffer than PETG (not as stiff as PLA) and takes quite a beating and is pretty tough. And for us very important!!! we get it from toner plastic or hobby king for $8-$12/kg. So in our experience it takes more of a beating than PETG for the same thickness and as a little side bonus its tensity is 1.04 as compared to PETG and PLA that are int the 1.2something. Now it is not on top of the our list. There is Nylon 910 or CX12 but at usually priced 50-80/kg its a bit too pricey for us for most applications. Even though the frame above has only about 14 kg of hips in it there are spare parts and then there are a lot of fails 99 % of which where what we call iterations (things don’t always work the first time) so we bought 40k for the season and still have about 7-8 now that was a 400 investment whereas in Nylon 910 it would have been a 3200 investment. And that is more as the total budget we have for building the robot.
Now the 1/2 in 3/32 wall aluminum square tubing bends less than a Churro is about 1$/foot (we got about 100 foot sponsored from a local supplier) and it is very light I think the 100 foot are a couple of lb. For hardware we are currently moving from 8-32 and 10-32 to M4 and M5. We don’t print for 3DP sake but as it affords us at our budget level to build a composit robot that hopefully will perform well while cadding and machine making everything the 3DP gives our hand tools the accuracy as the holes are in the covering plastic and can be used as guide holes.
Now this 2 in diameter winch with a grade 8 8-32 bolt inserted to handle the cable in a test lifted 300 lb without breaking
Now if I take a 1/8 in aluminum 1x1 l piece and complare it to a similarly dimension piece of hips the aluminum will bend before the HIPS will break but the aluminum will bend more and stay in one piece whereas the HIPS will take so much and then break into 2 pieces (PLA will break into many pieces) so at least in theory we are trying to leverage the good parts of both. The HIPS keeps the aluminum in the frame from deforming and if the HIPS gets hit too hard and fails the aluminum keeps the broken pieces together as its bolted to the plastic ever so often. Reason the elevator part is not completely covered in HIPS atm is cause we had to skip due to our printing capacity and the need to also have some spares. We currently have 2 Anycubic Chirons (one owned by me and one by the team) which we bought for $ 400 each and saving for a 3rd one. We currently also have a makerbot replicator which does PLA only. We received 3 inoperational ones and made one working one out of it. Once it becomes broken and unfixable - well that will be it for makerbots as we can get an anycubic Mega or Ender for less than the cheapest replacement part of those printers. The aluminum plate was sponsored by someone with temporary access to a laser cutter.
