Solved Sainsmart Lead Screw Wobble

Hello all, I am new to 3d printing and just got a R1. I have been fighting z banding using all the great info you have been posting. My latest attempt is the Sainsmart lead screws as ROBO is out of stock and doesn't have an ETA on their upgrade kit. I just received one of the Sainsmarts today and I tried rotating it by hand to see how straight it was. I noticed it deviates about 2mm or so at the end, I just wasn't sure if this is in spec for them and to not worry about it, or if I should get an RMA. My shipment was split, I will get the other one tomorrow.

 

Hello.........My suggestion would have to be, since they are so easy to install, try'em & see what transpires.........Z bandin' improves greatly, keep them.......nope.......... RMA..... 2mm is getting close to 0.1" ...........but check with the xperts here & listen to what they have to say...........Hey "proceed with caution"..........Take Care & welcome

 

Thank you both for the fast responses and info. I will give them a go then and let you know what I find out. 8)

 

Well... I got the other one in today, and it appears one of them is the incorrect item. I am guessing the shorter nema 17 with the longer lead screw is not the correct one. The taller nema one has a lead screw that is about 250mm high (exposed), and the shorter one is 300mm. And the best thing is the one I am assuming is correct, moves about 4-5mm at the top. There was no packaging in the box this one shipped in other than the manila bubble envelope it was packed in, and the box is about 14 inches wide. I think I will have to do an RMA and order some direct from a different seller on Amazon at a higher cost. I sure wish ROBO's kit wasn't sold out. 8)

 

I think the 300mm one is the one you want, the shorty. You'll loose some height on the 265mm. I couldn't find anything specific off of the number on the 265 but I did find the below on the 300.

http://www.aliexpress.com/store/pro...m-screw-length-300mm/1755857_32323473095.html

 

The larger motor...48mm... specs are:

• Rated current (one-phase): 1.2A DC
• Rated voltage: 5.5V
• Stepping angle: 1.8°
• Insulation grade: B grade

Specifics:

• Operating Conditions: Environment Temperature: -20~50℃; RH: 90%MAX; Mounting Position: Axis horizontal or vertical installation
• Direct-current winding resistance (25℃): 4.6Ω±10%
• Winding inductance: 7.4mH±20%
• Cogging torque: 24mN.m REF.
• Holding torque: ≥550mN.m（I=1.2A）
• Max. no-load starting frequency: ≥1500pps
• Max. no-load running Frequency: ≥2000pps

The suffix....265N....is the description of the shaft or lead screw........265mm length......

Just some additional information..............Take Care

 

Good thing I posted! I will keep the 300mm then and replace the other, thanks guys!