Fiberglass/Carbonfiber Reinforced 3D Printing Release

Just before the season an example on what we settled on so far. Now OTOH you can buy a couple of Marforged and even then you only get the fiber in the direction of the layer. Now this has been printed with an Anycubic Chiron and is just an example of what we will do


Still some cleanup needed but its mostly fiberglass.

Here is the manufacturing sequence

1.) Design the part in this case an L bracket. It has quite a few holes but only a few will be used at a time
2.) Print the part. This one is printed in HIPS. The wall thickness is .88 mm
3.) wrap it in Fiberglass. So cut some cloth, soak it in a resin of your choice this one in Marine PolyE (yes 2 part - still looking for one that does not need mixing) This one has 3 layers of 6 oz cloth. Then wait an hour and use the 3DP holes as a guide to cut out with an exacto knife. You wait too long you need a drill probably so you want to cut the holes while still tacky.
4.) let cure for about 24 hours.

Now this L bracket is just for some testing mainly the test I am running today is dimensional accuracy, How tight a corner you can turn and when and how to trim with the minimum of FG dust And comparing cloth single layer, cloth multi layer, mat and mat/cloth combos and how it sticks to different 3dp structures, materials.

So here is some results
1.) Cut the cloth/matt oversized (about 1/2 to 1 in) as if you come right up to the end it sometimes can curl a little
2) 6oz Cloth has .010 - .012 in (.25 - .3mm) per layer. So the piece you are looking at has .88-.92 mm HIPS and .75-.9mm FG. So almost 2 mm
3.) 1700 (17oz) matt with a 45 weave is about .060 to .070 in so about 2x as thick as 3 layers of cloth with the same weight
4. The whole L bracket is 320mm (12.61 in_ Long and 4x1in with the 2mm FG wrapped over was you can see (6in clothe “tape” was uses) and weights 3.0 oz.

HTH If you want to build up thickness then layer mat andmaybe 1 or 2 layer of cloth on the outside if you want to paint or go for the look. As for time considerations… It took me about 10 min to design the bracket. To print 2 took 3h and 45 min on one printer but we got 3 to use. then about 10 minutes to set up the FG stuff and cut the cloth and less than 10 min to wet the cloth and apply and then let try. So now an interesting question is does the waiting time also count in case you want to produce ahead cause I spent less then the 30min of my time to make 2 brackets I probably could have made 10 in less than 30 min. All in all it will take a little over a day (about 4h printing and 24 hours letting it dry) to have the finished product.

Now those 2 items won’t see the robot so the last question is academic but probably some like it with a cloth/mat sandwitch to bring the overall thickness to about 4-5mm

The 3DP in this case is for the accuracy and just a skeleton. the reason its .88 thick (except at the bottom by the holes is cause that is the thinnest we can print an item that size and keep it straight and a 90 a 90 etc. The bend is on a 6mm radius which is the tightest to mat can go. Cloth can go down to a 3 maybe less if you push it. So that final production item should come in close to 5oz per foot.

Couple more tests to run before the season starts but it looks promising With the standard resin sticks well to the 3DP plastic so now the questions need answering is how much 3DP and how much FG or CF and maybe occasional 1/2 in 16 gauge al. tubing to add quick stiffness where needed to get a composit that is best suited for whatever task we will be using it for so as we will be building or robot there will be a lot of note taking (which we will share ) as for stiffness, deflection, tensile strength etc. The above bracket at 2mm is pretty tough - way tougher than 2mm of 3DP only but still quite flexible which is both good and bad depending on what you are using it for. But one easily could add stiffness by printing and then wrapping a tube on the edge in the direction stiffness is wanted or raise the hole like on the 1 in part etc. (thats why that part is different. I think for robotics this technology has promise.

9 Likes

All in all, how much time would you say this process takes? Let’s say you’re making something like your bumblebot with the composite reinforcing; how much time do you think that would take during the season?

Depends on the tasks we have to do. But to do lets say a skateboard for Mechanum then the 3DP part will be about 90 printing hours. We have 3 printers now so that means a little more than a day as we can run the 15h prints over night so say 2 days. The glassing - depends how many people you got working but we got 2 tables - 2 teams about 1.5-2hours with setup and cleanup and that includes the 3DP stuff for the electronics board and battery holder etc. Now comes the for whatever reason difficult part to take apart and clean and reassemble 4 toughbox minis. We have done that in anything from an afternoon to a whole week (argh) and bolt them to the frame with the holes already in the right place. But then you never know. Last time for the off season we had everything and did get nothing done for 2 weeks and then put it together the day before and finished it in the pits. So lets put it this way. If I got 3 printers and me and 3 serious individuals you can do a skateboard in 3 days filament,glassing to drive it around. Now any other stuff. Figure Cadding and then guess the weight we can print 1kg per printer per day without pushing it too much - except gears cause usually we dont print them with a .8 nozzle. Gears at a rate of about 300-400g per day per printer. Now that figures established things like the frame. On new stuff longer as there is always the OOOPS I used inches instead of mm or something like that factor. SO IOW like every year in the past 10 years I have been doing that I say we should be done by the end of week 2 and have 4 weeks for practicing and then way too often we finish it in the pits and hustle to get the robot out for match 1.

1 Like

In our case the plan is - if this year uses a robot with 4 or 6 wheels. To crankthe printers up at kickoff and have all the 3DP parts for the basic frame ready for glassing for mondays meet.

1 Like