3D printed drive belts for a B&S 510 surface grinder

[gregoryd]

Sharing something I tried and seems to be working out. The o-ring belts on my newly aquired 510 surface grinder were junk and needed replacement. From searching around it seems that they are a non-standard size of around 0.260" diameter, and are around $30 each for the 5 or 6 needed.

I ended up 3D printing some using a 1mm nozzle and slicing in a way that it is mostly concentric rings. I used Ninjaflex TPU since it seems to be one of the stronger ones. After printing I gave them a quick flash with a propane torch to burn off strings and melt them together a little better. Only issue was I made them about an inch too long so I ended up spacing the motor out.

So far they seem to be working well. I let it run for 1/2 hour and they did not seem to heat-up. A quick grind with a random wheel on some unknown steel gave a nice mirror finish.

Maybe this will help you.

 

[4GSR]

I think most of us used a 400 series O-Ring for replacements.
I have the 612 version of this SG. Mine came with a flat belt in place of the O-Rings. I replaced it with a 10-groove Poly V belt and sheaves. Been working fine for the last ten years without missing a beat.
BTW- Like the idea of 3D printing a set of O-Rings, have to remember that the next time I need a emergency replacement O-Ring.

 

[BoxcarPete]

Having printed with Ninjaflex TPU before, I would not trust it for a seal. It should be just fine for a drive belt like you're using, but so would a -400 series o-ring as 4GSR has done.

The problem with using a printed seal is primarily the surface finish, but even if that is corrected by post processing bear in mind that the FDM strings are laid down onto material that has already cooled, so they're essentially filled with tons of cold-shuts which could cause leaks or worse. TPU has somewhat limited chemical compatibility as well, so that's something to consider also.

You could try it in an emergency though, if the need is sufficiently dire.

 

[dgfoster]

So, Pete, I learned about Ninjaflex from your post. Very interesting material. And one I will likely use at some point for some purpose that requires a flexible, chemically resistant printed part.

However, I would wonder why polyurethane belting which is available in a wide range of sizes and shapes would not be a better alternative for this application. I have heat welded belts that have lasted for years and were dead simple to make. Why would one choose NinjaFlex over polyurethane?

Denis

 

[john.k]

When one has toys,one must use them ,lest her indoors starts objecting to the accumulation of more toys.

 

[BoxcarPete]

So, Pete, I learned about Ninjaflex from your post. Very interesting material. And one I will likely use at some point for some purpose that requires a flexible, chemically resistant printed part.

However, I would wonder why polyurethane belting which is available in a wide range of sizes and shapes would not be a better alternative for this application. I have heat welded belts that have lasted for years and were dead simple to make. Why would one choose NinjaFlex over polyurethane?

Denis

Yeah, it's pretty neat stuff. Stronger than most 3D printable material I've worked with. If you're looking to use it just get ready for some headaches if you have a long distance between your feeder and nozzle. On the printer I used there was only about an inch or two, but that was plenty to cause pretty severe stringiness issues. Since it is an elastomer, it's nowhere near as stiff as most other filaments so when the extruder stops extruding, there is a lot more material that creeps out, and when the extruder starts up, it squashes down some before anything goes through the nozzle.