@dlang if chains are in perfect condition, pulleys spin freely, rope not dragging on anything to cause friction, not using too many pulleys: about 5lbs for each chain. If any links have imperfection and “stick” sometimes, increasing weight to 9lbs completely eliminates problem.
I have about 20 cutting hours on current counter weight setup with our wood Maslow, not 1 skip. Happy to report it has worked so well, we started adding same system to our metal Maslow
hmm, since the tension on a stock system is only just over 3 pounds, this means
that you are going through 0 tension and backlash comes into play in the bottom
corners.
going to a 12’ beam increases this minimum force to 6.4 pounds so the 5 pound
weight would work and avoid this problem.
Has anyone modified the bolt through design for a unistrut top beam yet? I need to do it relatively soon, and I just wanted to check and see if anyone has a hardware list.
For those using the plastic spacer on the motor mount to keep the chain tight to the sprocket can you tell me what length of scew bolt you used to attach the spacer to the motor through the motor mount. Thanks if you can.
OK, so I just wanted to show the community what I came up with for a Pulley and Counter Weight Tension system. Simple, effective and inexpensive. This would be better if the top Pulleys were larger but they are what I could find locally. I used 2 paving stone style bricks, some 110 lb. Para-cord, a set of rollers for a sliding door found at my local big box store and some L brackets to mount the Pulleys/Rollers. Total cost was less then 10 bucks as the bricks I got from a friend. Anywhere the cord comes into contact with the machine I used an old candle and waxed the surfaces and the cord. I also placed a piece of ply between the weights and mounted it to the waste board to keep the bricks from tangling, also waxed to ease movement.
I measured with water and since 1 litre is ~ 1kg I can say that it’s ‘ok’ with 1.5kg and perfect with 2kg (~4.41 lbs). I assume that gets divided by 2 because the chain is double.
Thank you this is a fantastic mod for the bolt together frame setup listed on the home page. I used a 33 inch bunge and it performed the test cut (4 cornters) flawlessly without any slack or too much tension. Much better than the constant babysitting and multiple misadventures with the design on the instruction set.
That sounds good and below the stock frame tension.
I’ll bet that we see a slight accuracy improvement with weights like this vs
bungee cords on the same amchine (recalibration should be done between them as I
expect the bottom width cuts will vary just a smidge as a result)
I got the top pulleys at a local Home Depot or Menards, they are actually rollers for a pocket door. I still think a larger diameter pulley would be better but once again , these are what I could find.
McMaster want $26 for ONE. My normal Chinese searchs aren’t turning up anything. There are a few on ebay for $10, but I’m thinking these should be pretty cheap commodity type items?
So… Does tension on the other side of the sprocket give accuracy? Are we otherwise gradually pulling it out of calibration? Forgive me, I just want to understand risk/reward on this. I have had no problems with the included design and yet I haven’t had to deal with precision just yet.
