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A couple of months ago, I bought a new Port Cable PCB375SS at Lowes. Relied a lot on the brand name. Maybe that's a mistake. At any rate, I noticed several posts here referring to blade wobble. My first "assignment" was kind of a quick mass production job to cut a bunch of cardinals from 3/16" balsa. Not real tough for me or the saw. That said, when viewed from the front, the blade's movement just didn't look right. Seemed like there was some sort of lateral movement. Took it to Stanley / B&D shop and they said "it's normal." Eventually, I videoed it. You can see it here: https://www.hightail.com/download/dDZGeVdrMVgrV3hBSXRVag In the last couple days, I started opening up covers to try to learn more. This is what I found: Took rear covers off the saw, which exposes the back end of the top and bottom rocker arms, plus the connecting bar. Tried wiggling the arms side-to-side. No movement. Seemed pretty tight. Looked down tube housing upper arm towards blade end. Could see the "Special Bolt" on which the arm rocks. Access is hidden behind Porter Cable label on right side.. Very reluctant to access. Looked down tube housing lower arm. Can't really see through. "special bolt" is accessible. Looks like it can be removed or whatever with hefty hex key. Looking again, it appears that two different size hex keys are used here. No idea why. Again, didn't touch it! Removed plastic cover from left side, opposite motor. Blade is under normal tension. Again, everything seems pretty tight. Tried rotating the "eccentric" as motor would turn it, observing blade. At table level, At start of up-stroke, blade clearly shifts to the right, about 3/64". No slop to blade at that point. During upstroke, blade remains in that right-shift position.No real slop. At start of down-stroke, blade clearly shifts to left. During entire down-stroke, blade stays in the left-shift position. If "eccentric" rotation is reversed so that blade direction is reversed, blade position shifts. Example: during down-stroke, when blade is in its left-shift position, if I reverse direction, blade will shift to right. Further note - resistance is encountered when blade switches from down-stoke to up-stroke. Opposite holds true also. Tried to observe action of connecting bar at rear. Checking at about the midpoint of the bar, On the bar's up-stroke, it shifted to the right side of the saw. Conversely, on the bar's down-stroke it shifted back to the left. I tried to gauge how much movement there was at the front of the arm, but found that much more difficult to do. My guess is that the maximum shift was 1/32". I finally gave up trying to gauge the movement at the front of the lower arm. Bad view, angles, light, and all that stuff. I tried to gauge how much movement there was at the front of the arm, but found that much more difficult to do. My guess is that the maximum shift was 1/32". I finally gave up trying to gauge the movement at the front of the lower arm. Bad view, angles, light, and all that stuff. I'm trying to avoid returning it to Lowes, but I think I'm just about to that point. Any comments from anyone?

Here is a list of the small VXB bearing part numbers for the DeWalt 788 Scroll Saw, and it's likely that the similarly designed Porter Cable and Delta scroll saws also use the same bearings. This is not my list. I managed to loose the good complete list that I made along with my invoice from the bearing store where I bought them, so this is a re-post of someone else's list. Here are the VXB Bearing part numbers These bearings can be sourced from VXB Bearings (800) 928-4430 , but most bearing stores also stock these or can get them for you. They will cost less through other sources than buying them from DeWalt or ereplacementparts.com as spare parts. http://www.vxb.com/p...earings/PROD... Kit8616 (HK0609 Needle Bearing 6x10x9) qty needed 12 Kit7492 (HK0810 Needle Bearing 8x12x10) qty needed 2 Kit7189 (HK1412 Needle Bearing 14x20x12) qty needed 2 When I bought the full set of bearings for my DeWalt I asked the counter man at the bearing store if he had any higher quality bearings for any on my list and he said "Oh yea" and then filled my list from them. Many bearings are made by different manufacturers and some are better quality than others. All have identical part numbers, but sometimes with different suffix letters after the part numbers. These guys know who makes the better quality, tighter tolerance bearings and will give you better ones if you ask, but it may cost slightly more than the cheapest ones. Unfortunately, I don't have the invoice so I can't tell you what I ended up with, but my saw was much quieter than the new DeWalt saw of a friend's after I replaced them all. The larger sealed bearings that are located near the motor (the ones in the connecting rod and rocker arm) "must" be pressed out to be replaced. DeWalt sells these assemblies complete with the bearings already pressed in. The www.ereplacementparts.com numbers for these are Rocker Arm Asm 286268-00 present USA price $63.83 Connecting Rod Asm 286280-00 present USA price $28.82 But if you have an arbor press like this one from Harbor Freight http://www.harborfreight.com/1-ton-arbor-press-3552.htmlor a larger drill press, you can press out the old bearings and press in the new ones and save considerable money. When I replace bearings in my shop tools, my lawn mower, cars, etc. I use my bearing press frequently. So for me, this bearing press paid for itself very quickly. In the two assemblies above, I don't think there is $20 worth of bearings in them, so you can see how quickly this press can pay for itself if you have a frequent need. Bearings are very hard to keep straight while pressing them in and out without using one of these presses, and it's easy to crack aluminum castings if you should get a bearing crooked while pressing it in or out. I usually press the old bearing out, while at the same time pressing in the new one. You may also find that a bearing press will help sometimes with the smaller bearings too, especially if you don't have much or any experience changing bearings. When I need DeWalt replacement parts, I usually buy from www.ereplacementparts.com because they have always been good to me. Sorry, since I lost my bearing list, I don't have the bearing numbers for the larger bearings any more. You will need to get them from the bearings in your DeWalt saw or wait until I or someone else performs maintenance on our saws again and posts these numbers. They are etched into the side of these bearings (very small - you will need magnification). The list above are the bearings that will likely wear out more frequently anyway. Every bearing that rocks back and forth constantly without making a full revolution (all except for the bearing at the motor shaft end of the connecting rod) will have it's lubricant gradually driven out of the load areas by this rocking motion. Once the lubrication is gone from these load areas, the bearing balls or needles and the bearing races (inner and outer ring) begin to wear. Fortunately, the little HK bearings used in the 788 have a removable center race (sleeve), so this sleeve can be removed and a tiny bit of synthetic instrument grease added (I use a tooth pick as an applicator) to the inside of the bearings through the center hole (wipe the grease onto the needles in the sides of the bearing hole, and then the sleeve (which is the inside bearing race) can be replaced. When you do this, spin the sleeve a few revolutions to distribute and mix this new grease with the original grease before replacing and securing the bolt. I use Blue Locktite to secure bolts (absolutely do not use Red or Orange) Also try to position the sleeve so it is not in the exact same orientation as it was before you removed it. Then replace the bolt or pin through the center of the bearing and secure it. In bearings that rotate 360 deg, the lubricant is pushed ahead of the balls or needles inside it, and is constantly being redistributed around the entire inside of the bearing. They will last much longer without any attention than the ones receiving a repeating motion of less than one revolution. Unfortunately, by the design of a scroll saw, only the bearing in the motor end of the connecting rod assembly receives a continuous 360 deg motion. All of the rest of the bearings receive the partial back and forth motion, the motion that is so hard on bearings. All that we can do to prevent them from wearing out too quickly is to add some light synthetic grease to their insides during scheduled maintenance. Only remove one side cover from your saw at a time. Removing both side covers at the same time will cause your saw to fall apart. There is no internal frame in the DeWalt or similarly designed Porter Cable and Delta Scroll Saws. The saw will fall apart if you remove both covers at the same time. Also, dis-assemble only one small assembly of the saw at a time to be certain that you can put it back together the same way before moving to the next assembly. With a cell phone or small camera, pictures can be taken before dis-assembly, to make putting it back together the same way much easier on your memory and the saw. In addition to doing the bearings for general maintenance, check the condition of the bolt that connects the vertical rocker piece and connecting rod, back near the motor. This bolt receives a lot of force and can loosen or break. I replaced my bolt the last time that I had my saw apart. Some have reported that their bolt loosened, bent, or broke. So check it's condition carefully and replace it if necessary. It's a metric M5 cap screw that can be found in the better hardware stores, Lowes, and Home Depot, and it isn't expensive. Buy one the exact same length. These are available as stainless bolts too. Either black or stainless cap screw should work very well. While your saw is apart, look around for other moving parts beside the bearings and put a little oil on them. The shaft through the center of the Rocker Arm has a sleeve that could stand a little oil. Again, use a high quality light weight oil for this. I use Tri Flow. There are other places for this oil, but I don't have them memorized. Charley