Markforged printers which one?

We found on some pulleys we printed with a 3/8" hex bore for our cargo mech that the hex started to round out. We broached them out to 1/2" hex and put the 3/8" to 1/2" hex adapters that WCP sells (and made some of our own) and it seemed to solve the problem.

So I guess lesson learned is the face width on 3/8" hex bore isn’t quite big enough, but 1/2" hex seems to be. We will likely continue to print pulleys and use this practice again in the future (currently using it on our off-season swerve module).

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We rounded out a 1/2" hex, but had a lot of torque on it. A Versa Hub pattern distributed that load nicely, though, and it held up just fine for what little time we played with it.

This season we gained access to a Mark 2 through my work and we printed approximately 15-20 unique parts for our robot on it. All were printed without any reinforcement because, as others have stated above, it was not found to be necessary. I’ve included a picture below of the most critical/load bearing printed part that we had on our robot this year. It’s an elevator brake that functions by clamping the lift belts for the first stage of a cascading elevator into the fixed tooth profile and relying on the tooth shear strength of the belt to hold the elevator in position. This was used only during our climbing sequence where after deploying our suction pads and lifting the robot into the air, two of these assemblies clamped down on the two belts on either side of the elevator to hold the robot in the air even after power was cut. Each brake has a single “U” shaped printed part where one face has the inverse belt tooth profile, one face has the mounting pattern to fix the part to the frame of the robot using 3 #10-32 bolts, and the final face has the mounting pattern for the pneumatic cylinder. We were slightly concerned if this part would be durable enough to last but we used it through DCMP and CMP with no problems. For reference it was printed at 100% infill Onyx only. After our experience this season, I would recommend any team invest in one or more Onyx Ones rather than a Mark 2.

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We have not rounded a 1/2in hex yet but we had a 3/8 skip and emploid the same solution you did. What material did you round? was it the Markforged Nylon? What is important with hex seems to be very tight. I.E. it becomes a press fit. And high load? That is relative we lifted 1/2 robot with one on a 1in diameter gear. (front or rear elevator)

There is no discount for the Onyx One. Retail is$3500.

This is true, zero discount for Onyx One. Teams are getting roughly a $1000 discount on the Onyx pro and roughly $1000 discount on 10 spools of Onyx.

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We have the Onyx One, so yes, the nylon with chopped fiber is all it prints.

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Little to pricey for me - maybe try some taulman 910 with an ID on the hex of 12.9mm and then use a vice to force the hex in or a C clamp.

We saved up and sprang for the Onyx One – it doesn’t cost any more now than a Makerbot 2 did seven years ago, and as our 2 was nearing the end of its functional life, it made sense to upgrade rather than save the funds on a comparable PLA or ABS setup. We have no regrets on the decision!

Good for you. We have a makerbot in the school and I would never buy one… We had only a 1200 budget plus for what we do we try to keep the average filament costs to under 30/kg. 3D Printing has become an integral part so for example we did smokey bot for a sponsor of our which was an 8kg project which we did for <25/kg so less than $200 which meant ther was more of that sponsors money left for other projects because he just donated a certain amount. Right now we are doing that 400:1 gearbox project. Again about a 5kg filament project. So the filament cost was meaningful for us. Everyone says there is a discount for FRC teams but no one has spelled out what it is. Guess you got to order it and pay for it to find out but I would be very surpriced if it was <$30 /kg average. Now I’d love to have a markforged preferably X1 but I’d also like a supercar (preferably mercedes) yet drive my Hyundai.

What makes the onyx one any different than any 3d printer that takes nylon ?

Attaching this as people seem to be mixing up the printers. It seems the consensus here agrees with my research that the plain ole Onyx One (lowest end model) is more than adequate for our purposes.

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Isn’t the onyx one just a normal 3d printer tuned for nylon …

pretty much.

There is no discount for the Onyx One, and there are no filament discounts for FRC.

The Onyx One filament is nylon impregnated with chopped carbon fiber.

90 percent sure you can print that on other printers

Oh, Markforged isn’t the only game in town, but I’m pretty sure it’s the most affordable.

We’ve had a part this year that went from 910 to NylonX to Onyx. Same loading, same design, same mechanism.

The Onyx parts are considerably more impact resistant that either of those. 910 in particular (while a great step up from PLA) has nowhere near the impact resistance of Onyx.

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See this thread:

The MatterHackers Pulse XE is a significantly cheaper printer designed to print NylonX, which also contains chopped CF. Other FDM style printers can be modified to print materials like NylonX, and XT-CF20 (PETG, I think, with chopped CF in it). I have not seen anybody try it, but I wouldn’t be surprised to see the Pulse print Onyx very well.

I can print Carbon Fiber infused Nylon successfully on my $1200 printer. I just don’t choose to ATM as layer adhesion right now trumps the extra rigidity and price penalty.

There are 2 kinds of printers out there the ones where you need to really know what you are doing that are at the low end and usually sold as kits and the ones like the Markforged and Ultimakers etc where you buy into an environment/universe and can produce good results as long as you stay within that environment and are willing to pay the premium for that. Me - for 10k I’d get about 6 prusa type printers and modify them to my needs and then I probably can print a whole robot using 60-70lb of filament in less than a week.