Best posts made by DrDFlo

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The craziness of life and some now fixed printer problems have delayed this project... But, I am hoping to set sail during this upcoming 4th of July weekend!

Also, in my home state of Tennessee any watercraft under power (even one with an electric trolling motor) needs to be registered with the coast guard or else I am going to be stuck sailing on private ponds outside of strip malls lol! So, I will have to address those state regulations during the design/printing of the boat.

As a side note, I was rewiring an old Flashforge at work, and man, my latest upgrade to CAN expansion boards on the large format 3D printer has completely spoiled me... I am excited to see what other expansion boards will be released. I still have my fingers crossed for a digital or analog galvanometer expansion board as I am still tinkering with my SLS printer build, but this would also be useful for any laser marking application.

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@o_lampe said in Dr D-Flo's big build:

If you refer to the closed loop steppers; IMHO they are just band aids to cover up some design issues. Maybe related to the donations from sponsors? Sometimes you have to use, what you got, right?

I was referring to pellet feeding issues, but I am open to discuss any of the printer's design elements. Of course, the overarching design constraint was capital. So let's assume that you had the same budget as I had, which was about $7,000 for the frame, 7 linear actuators, and custom brackets to attach everything together. BOM here. Would you source completely different components or tweak the ones I had?

A bridge-style mill or Kuka robotic arm would both be better platforms for pellet extrusion, but the cost and power requirements are prohibitory for my garage operation.

I am upgrading to a 12 mm high-helix lead screw for faster travels at lower RPMs, but I am limited here by the c-beam aluminum extrusion profile

@o_lampe said in Dr D-Flo's big build:

BTW: we recently discussed galvos here, maybe you find some inspiration for yours?

Excellent, very timely!

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@T3P3Tony

@T3P3Tony said in Dr D-Flo's big build:

Ivan's print head is significantly lighter than yours but belts appear to be working for him on a similar size printer:

@Phaedrux said in Dr D-Flo's big build:

Modix does.

Perhaps, I wrote a standard FFF belt configuration off to quickly, but with pellets, my print head weighs > 30 lbs (13.6 kg), which is likely 10x heavier than Modix or Ivan's. For a belt to work, I will have to use a thicker belt and tensioning will be a concern because those c-beams are likely to buckle.

@JoergS5 said in Dr D-Flo's big build:

There is a solution which may interest you, called ServoBelt:
https://www.cnczone.com/forums/linear-and-rotary-motion/59570-forum.html

A pinon belt system, such as the one you linked is definitely interesting. I need to think about it more, but it may be possible to implement with with only a small modification to my carriages, if I can run the belt on the back of each actuator. I see that Bell-Everman NEMA 23 actuator supports 50 lbs. Cool!