Well here is the "Husker" 2x72 belt grinder I made. It's been named the "Husker" by Rob because of all the corn in the background So far everything seems to be working alright. I have to make a platen yet so we will see how she goes then. Here are a couple pics!
Thanks guys, those indeed are longboard wheels they make good little contact wheels too! I think it needs to go a little faster tho. It's a 1.5 horse 1725 rpm motor running a 3" pulley on the motor and a 2" on the drive with a 6" drive wheel but it still seems a lot slower then my 1x42.
Looking good Jules. Rough estimate on belt speed should put you close to 3500 sfpm. Rough math says motor at 1800 on 6 inch drive gives about 2700 with a 40% overdrive on the pulley should put it in around 3300 to 3400 but that's just mental figuring with no calculator. Mine currently runs just about 4000. Which is still probably slower than the 42 incher.
Thanks for figuring that out! I just picked up a 3-4" variable speed drive pulley for the motor,a 2-3" variable speed pulley for the drive shaft and a red link belt. When I have the motor at 4" and the drive at 2" it screams along pretty good but still not as fast as my 1x42. I think it's fast enough tho. That should put it at over 5000spm right? One thing I did notice tho... The higher the speed the further to the right the belt tracks. If I track the belt in the centre at full speed it moves over to the left about 1/2" when I shut the grinder off. On the lowest speed it doesn't move at all. I don't know if that's from the frame flexing or the wheels being out a little but its kind of frustrating. How many pounds pressure are you guys running your belt tensioner at? I'm guessing mine takes about 8-10 pounds to push the tensioner down. Does that seem a bit high?
No expert here but I would think 8-10 is low. Within reason more tension is better for tracking. I know guys using the hydraulic or air springs like you have there and running between 25 and 35 lbs on them. Just read a thread about it the other day but can't remember where. I was recently having some tracking issues under load with my own grinder. I resquared everything and tightened my spring up a bit and it fixed it right up. However I have no idea what I am running for tension now. Also the pulleys you picked up give a 2:1 ratio roughly so that should get you in the 5200 sfpm range, which is screaming fast. You will likely notice your ceramic low grit belts cutting better and lasting longer without glazing. You will also however, likely notice it cooking high grit belts pretty fast at that speed. I have noticed anything above 400 grit burns out faster at my 4000 plus speed than it did at my old 2900 speed. Sure does hog faster though.
I'm going to have to take a fish scale to it. Maybe I'm just super strong or something lol. What did you use for a platen? All I have kicking around is a piece of 2"x3/16" 1084 I wonder if I should harden it or not.
I used a piece of 2 x 2 angle iron with a piece of princess auto ceramic fireplace glass. So far the glass is holding up great.
I haven't looked lately here but when I went to a local glass place to get it cut they were telling me they sell the same stuff for $80 a sq ft and that they were going to get everything princess auto had.
i use a graphite anti friction pad available from b and w steel supplies in lethbridge-sold by the sheet and has an adhesive back-designed for larger belt sander-just cut to fit
sweet molasses !!! the Husker is chuckin metal !! nice job buddy and that first flat grind looks awesome ! .....yes I would heat treat your platen, I have an chunk of O1 on hand for when the time comes to replace mine .......
Oh yeah buddy!!! The Husker chucked a lot of metal today!!!!! I had about a quart of metal dust on the ground when I was done That was by far the best thing I have done to improve my knives. Those 36 grit ceramic belts are awesome!!!! I'm not to impressed with the 120 grit zircs tho. For 120 I might try a slower speed and use AO belts. Ill post some pics of what I ground tomorrow sometime.
