View Single Post
Old 03-08-2013, 01:11 PM   #87
Super Moderator
diredesire's Avatar
Join Date: Mar 2004
Posts: 6,694
Send a message via AIM to diredesire

Originally Posted by TheLambsheadrep View Post
SUCCESS!!! Similar to DD's advise, i ripped off a 2inx2in square off a paper towel (kitchen brand, not bathroom brand), bent it like a taco and ran both strings through it as it sat in the gripper. Worked like a charm, multiple tension tests verified that the strings didn't slip drastically and the accuracy of the tension rod scale. I said drastically because for EVERY drop of the weight, the rod would stop slightly, but noticeably, higher than perfectly horizontal. I read the physics of the drop weight machine thread which says pushing on the tension rod to achieve a perfectly horizontal rod will shoot the tension up, but I didn't find this to be true the way I did it. I pushed the rod down in a gentle and spaced-out manner, and noticed that when I thought it was perfectly horizontal it read the selected tension plus or minus a tenth or so of it was supposed to be. But, pretty much immediately after the perfectly horizontal position was reached, the tension would decrease at about a pound every 2 seconds. I don't know if this is normal, or due to the upper string slipping slowly from the paper towel or a result of the tension rod slowly rising since me pushing it down did not let the machine achieve the perfectly horizontal balance naturally. Does the drum or any part of that area of the machine need to be cleaned, maybe that's preventing the rod from reaching horizontal by itself?

Anyway, I will probably take some more pics and video of what I am doing so you guys can see what I'm seeing. I am very happy though since the biggest issue I have (as of now, haven't even worked with the clamps and such haha) seems to be solved for the time being.

By the way, earlier in the thread I did say that the measurement scale on the rod was a sticker, not an engraving. I will probably need to replace it, does anyone have suggestions, can they be purchased? I was thinking that since the sticker values are accurate (for the few clear measurements still on the scale), I could do some measuring and record a new scale on masking tape and place it on a side of the rod that won't allow it to get torn up.
It's pretty easy at this point to verify whether or not the string is slipping, just use a sharpie and mark the edge poking out of the back end of the tensioner. If the mark moves, your question is answered. If you're only slightly above horizontal anyways, I'd just leave it alone. If you have clamp drawback, it'll probably come to rest at horizontal in the end. The results are within margin of error if you're within ~5deg anyways. As far as the tension dropping X lbs per Y seconds, this could simply be the string elongating/stretching. If you have scrap kevlar, you can repeat the test and see if there is any/much droop. Kevlar doesn't stretch too much once under tension.

As far as your sticker, I'd like to see a pic before a final rec, but I'd take a simple set of files and mark the major hashes (5 lb increments or so). Shouldn't take much more than a few seconds per hash. You can also get an engraving pen (or dremel) for reasonably cheaply to mark the majors. You might even get lucky and score something at good will, etc for a few bucks. If the visibility is low, just draw over the file marks with a sharpie and wipe clean, the ink should stay on the 'engravings'
4x Dunlop Bio 200 L // Babolat Sensor
Report posts, it helps everyone out!

Mod Qs/Concerns/etc? E-mail me! (please make return/profile e-mail is valid!)
diredesire is offline   Reply With Quote