VEVOR Linear Rail Slide SBR20-1200mm 2 PCS and 4 PCS SBR20UU Slide Blocks Linear Guide Rail and Bearings Kit for Automated Machines DIY Project CNC Router Machines

Work very well after years of use. Used 2 sets to make a router mount for levelling large pieces of wood. These made it easy to determine if the set up was level because the router would glide to the low spots at 1/8" difference over 5'. The set up has sat in the garage (hanging on the wall when not in use) over 3 winters and humid summers. No corrosion or wear. The cross set did show limited flex with minimal force, but these were not intended to be unsupported, had I mounted them to even 1/8" steel, the flex would probably disappear.

Excellent product! Worked great for my router table.

Very strong and smooth would definitely buy again

Very well made. Quite heavy. Slides well but one has to purchase additional ends.

Well made and the slides work very well. They were not cheap but well worth the money. After repeated use for the last few weeks, they work just like the first time i used them.

Looks to be very sturdy. I'll use them for a slab-flattening jig

Worked great in helping me create a slide for my palm router.

A straight edge laid across the bar shows a deviation of about 1/8 of an inch end to end. I was going to use these for a planer sled as others have done but with the bow in the rail you would get a board thicker in the middle than on the sides. 1/8 " would be a lot of sanding to make the board flat. My old mdf sled which cost next to nothing is a lot flatter. Also the aluminum ends are very roughly cut and protrude out from the round bars, so would have to be filed off if you wanted to put two of these end to end for the table part of a router flattening jig. One of the bearings had some play on the bar but the set screws on the block adjusted the tightness. Update: Contacted Vevor support - extremely helpful and very responsive. Found out that because the difference in the thermal coefficient of expansion between aluminum and steel the bars will distort as the temperature changes ( AL is 2x or more than steel you can visually check this by using a long straight edge and warming the bar/aluminum combo with a hair dryer). They had me loosen the bars from the aluminum and check them again - the distorted one was still distorted even if I removed the aluminum entirely. I sent a picture and Vevor sent me a new bar and it is straight as it should be. Five stars for support, 1 star deduction for sending a bad bar to begin with. For those that are building a cross flattening sled - I was trying to decide whether to use just the bars or the bars with the aluminum extrusion, not knowing how much sag the bars would have with the router and it's carriage. With the aluminum there is no detectable sag, so if you are in a temperature controlled environment then if you loosen and then tighten the bars on the extrusion it will not sag with a router. If, however, you have limited room like I do and setup your flattening system outside then the temperature extremes as far as I can tell could make the bar flex by .5 to 1 mm (depends on what the temperature is and what the temperature was when the bars were tightened). Testing with just the 2 bars ( no aluminum) at full span with a 12lb weight in the middle then the weight appears to make it sag by about .3 mm. Temperature will not affect it. This is with 2 1200mm long, 20mm dia. bars. If the distance is shorter the sag will be less and if the bar diameter is smaller the sag will be more. Obviously if the router/carriage weight is less it will sag less. I am planning on making my sled with just the bars (which would have been cheaper had I known this ahead of time).

mycket bra produkt !

It is perfect

Los adquiri para una mesa de fresado y van muy precisos y equilibrados no esperaba que fuesen tan pesados. He leído que hay clientes que les llegaron torcidos. Los míos estaban perfectamente rectos y los rodamientos con cero holgura son fáciles de ajustarse y los materiales muy bien acabados y pulidos. La entrega fue antes de la fecha indicada la compañía de reparto era externa y antes de la entrega me llamaron por teléfono para indicar que iba de camino a mi casa. Encantado con la compra atraves de Amazon y con la compañía de mensajería.

DZIAŁA JA TRZEBA, BEZ LUZÓW

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