Thinking about a new to me jointer, how to inspect it?

A Crescent 16” jointer is for sale a few hours from me. I have a flooring project next year that will use a bunch of 12” wide boards so the timing is perfect. The photos show the machine to be in unrestored condition. The top is still bright, but the machine was painted yellow once upon a time. I’m not looking for a pretty machine, but I’ll demand an accurate one. I know this jointer has babbet bearing (it’s in the listing as being in good condition). The listing says that the jointer has a 4 knife cutter head, which I believe is the safety head. I’ll verify that before I go and look at it. The jointer has a 3hp 3ph motor. I’d rather not run a vfd for this one, so I may change it out for a 7.5hp 1ph motor that I already have. The asking price is $1,200 which might be a bit high for the visual condition. The question is how do I confirm the operating condition? It’s still hooked up so I’ll be able to run a sample board. If there sipe, i’ll know there is an adjustment issue, but that can be fixed. I keep on reading about people complaining about beds “sagging”, being “twisted” or not “coplanar”. Can you guys explain these issues to me and educate me on how to check for them? Anything else that I should checkout before buying?

Take a couple of flat 1x4's as long as the outfeed table and joint them on the machine at various points across the table. If you get a good joint between the pair everywhere then you know the tables are set up right. If not, use the best, longest straight edge you have and a set of feeler gauges to check the tables for bumps and hollows. If they are within reason (I would like to see them within .002" but some local bad spots can probably be ignored), and all the parts are there, the tables can be adjusted to make them co-planar. You can make an adequate wooden straightedge with an accurate jointer or sliding table saw.

Grab hold of the shaft and reef on it. If there is vertical play, look for shims between the bearing shell halves that can be removed to tighten things up. If no shims, the babbits probably need repoured which would lower the value a lot. Check the oil cups. If empty, the owner hasn't been paying attention.

Does it have a working guard? If not you will need to buy or fabricate one.

Are there any cracks in the castings? They can be brazed by an expert, but again that would be a major flaw.

Thanks for the tips. We're you jointing the 1x4's on edge or on face?

If you use the machining wood test, do it every 2-3" across the entire width. A 4' straight edge would be nice. Hold down on the outfield table, and bring up the infeed. Check every few inches again if the beds are in the same plane. Winding sticks can be used for checking twist, but I find that process less than precise. Check for backlash in the bed adjustment screws. I had an old 16" jointer that had a ton of backlash. You can still use it, BUT, every adjustment has to be completed by lifting the table. You take it below what you want, then lift the table to get the setting. Take the belt off to check babbet clearances. The tension of the belt can fool you. Check the fence for flatness and perpendicularity to the table. That can also give you a hint about any twist if the squareness changes along the length of the fence.

Just as Richard mentions, you can use winding sticks to check for twist. I have two 36" steel straight edges that I use for checking wind on important surfaces.

Make certain that your checking tools are accurate before you check the machine and assume the machine is out. If you have multiple straight edges, check them against one another for a 'quick and dirty' estimation of their accuracy.

"Thanks for the tips. We're you jointing the 1x4's on edge or on face?"

On edge. If you can get a consistent glue joint between the pair of 1x's that is evidence that the tables are well adjusted.

Expect to make adjustments if you get it and unless it’s been recently used it may be off a bit so don’t let that scare you off. Most likely you will need to take the tables off to move it. It’s probably 1000 pounds. The tables sit on 4 points so it’s easy to adjust them by shimming as required. Blades will need to be sharpened so you will need to set it up. Even new machines need some adjustments so expect to make them.

if it’s a direct drive motor consider the VFD. I have a very similar model which is based on the American Model 10. The cutterhead shaft is the motor shaft. I couldn’t find any couplers so I cut the shaft and mounted my motor below. It’s not that hard. If it’s belt driven it’s an easy swap out.

I like mine but it takes up a lot of room. It’s 24-36 (direct drive 36) inches wide by 6 to 7 ft long. If you have the room it’s well worth it. 1200.00 is a good price if nothing is warped or broken. Jointers of this size go for 1800-2000 so your on the low end. If you haven’t join OWWM and do a search. Tons of info.