Problems with my planer

[RPF2509]

I have a problem with my dewalt dw733 12 1/2" planer. I can lower it but can't get it to raise up   I've fiddled with it an now it's lowered to almost the bottom. I removed the under cover and exposed the linking chain but can see no obvious problem. I have noticed it getting harder to raise the last few times I've used it. It's a good 15 years old and has not been abused but this is the first time its given me troubles.  There is no debris jamming thing that I can see. I think the linking chain sprockets have slipped so the two screws that raise and lower it are no longer in sync  I don't want to start tearing it apart yet until I diagnose the problem better. In any case has anyone out there had a similar problem?  Any suggestions would be welcome. Thanks!

[Kbeitz]

Use an outside caliper to measure the distance between the table and cutter on both sides. This will tell you if something slipped.

[Dakota]

stick the air hose in there and blow all that 15 year old sawdust out of there.

[DDW_OR]

i did a quick look at the parts diagram and saw there are two threaded screws to raise/lower the bed, and a smooth rod.
could be as simple as a good cleaning and lubrication per user manual

[RPF2509]

Owner's manual was no help so talking around I think my original suspicion is correct.  There are two set screws that hold the sprockets onto the round threaded shafts that raise and lower the cutterhead.  The sprockets are linked by a chain so turning the depth handle on one side turns both the threaded shafts so the cutterhead stays level.  A friend says his planer did the same thing and the cause was the set screws loosening and the shafts getting out of synch.  So time to disassemble.  At least the set screw should leave a mark on the shaft so I can see where the shafts were originally indexed in sync.  Might just have to grind a bit of a flat on the shaft so the screws don't slip again.  I'll post pictures when I get further into it.  I'll even use the time apart to replace the blades since the originals just got a nick in them.  Still for the first problem after 15 years, I can't get too agitated.  Can't say I've used it heavily but I've used it regularly and yes I blew all the dust out before investigating and yes the cutterhead lock was disengaged.

[gachriswoodwork]

RPf2509, I do industrial maintenance, when we have set screws slip on shafts we dimple the shaft with a drill bit for the set screw it sit in and then locktite the set screw. No more slipping.

[Kbeitz]

I put two set screws in each hole if there is room for them.

[RPF2509]

.Its been too cold to work out in the shop so no news yet.  Thanks for all the suggestions on how to cure this

[Brad_bb]

You could always take it to the service center.

[TKehl]

If it's too cold, I'd bring it in and tear it down on the kitchen table.  It is a lunchbox planer after all.   ;D  It'll blend right in.   ;)

[RPF2509]

Warm weather has arrived so I tore into the planer.  My suspicions were correct.  Set screws slipped on the shaft.  I futzed with it quite awhile trying to get the screw shafts in sync and finally ended up disassembling and removing the support shafts, leaving the cutterhead only supported by the screw shafts.  I lowered it all the way down and used calipers to make sure both sides were equal height (front feed ramp came off to allow access).  Using my Dremel (no room for a drill) and a file I cut a flat on the shaft with the crank handle and tightened the set screw.  Getting the shafts synched was sensitive as less than a quarter turn off would have them binding.  After a couple trial and errors I got so I could feel the resistance when turned too far and marked the shaft for the screw.  Another bout with the Dremel and file and the second shaft was ready with a flat spot.  Reassembled the mess and put new knives on (man are they sharp!) A little wax on the shafts and a thorough cleaning and it was ready.  When finished the cutter head when up and down with minimal effort and hopefully is good to go for another 15 years.  Still it took well on1/2 a day to get it all sorted out.