Where to buy Triangular Teeth Extruder Gear

So, I turned my makerbot into frankenmakerbot to make it bigger. But I have been struggling for *weeks* to get it to extrude reliably. I want to get a triangular toothed extruder gear like this:
[2.bp.blogspot.com]

I know these triangular teeth work well. But, I need help finding where to buy it! Anyone know where? Thanks!

Edit: I noticed they are also called sharp spur gears.
Edit2: I finally figured out what it was!!! I had taken the heatsink off the extruder's aluminum block to try to cool the filament better. It worked great, but the filament ended up overheating within the block, getting fat and that increased the drag, sometimes completely jamming. So, I tried to increase the current to the motor, thinking that's what it needed... it ended up just stripping the filament sometimes and jamming other times. lol. A few more days of this and I probably would have taken a sledge hammer to the thing.

But I still would love to know where to get those sharp spur gears.

Dave

Edited 3 time(s). Last edit at 06/11/2013 09:30PM by daveycrocket.

looks kind of like a knurling wheel, for a lathe.

[www.keywaytooling.com]
[accu-trak.com]

but those are often carbide, and meant to free wheel.....still you might be able to adapt one.

Edited 1 time(s). Last edit at 06/28/2013 11:11PM by 1013.

I have an aluminum foundry and can cast these straight from aluminum. We could print a file then I can cast a mold from the plastic and pour it in aluminium as an exact replica. The only thing is I've melted my extruder isolator and waiting for a new one from hong kong. May be up to a week... However, we can make this from scratch. Message me if you're interested.