Jet JWP DX 15 planer.

Finally got back from Myrtle Beach and started cleaning and adjusting this machine. I have also found out that sometime in the past a blade either came loose or hit something metal, breaking the blade and putting some minor dings in the cutterhead. Evidently when this happened it cracked the casting in front of the outfeed roller. It's about 1.5" long and at the corner where the thin part of the front of the casting meets the thick side of the casting. Anyhoo, I'm going to take to a professional welder to drill the end of the crack (to stop it) and then to TIG weld it closed, you know good and well if I try it I'll screw it up. I'm going to try to find some old turd that has been welding cast for years and knows what he's doing.
My second thought is to change this thing from the straight blades to a Shelix helical head while I've got it apart.
Question is do you guys think this type of head will decrease the future stresses on the casting repairs, ya know many of small cuts instead 3 big impacts from the straight knives.

...Evidently when this happened it cracked the casting in front of the outfeed roller. It s about 1.5" long and at the corner where the thin part of the front of the casting meets the thick side of the casting.

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Sorry to read this.
At least now I understand why someone who spent over $1000 on 4 sets of new blades, decided to sell the relatively new planer.

Which side of head is cracked; belt drive side, or gear box side?
Would love to see a picture of casting and cutter head damage.
Have rebuilt many 15" four post planers and never witnessed that problem. Be handy to know where to look.

FWIW - When knives hit something hard enough to shock the planer drive line; there is small helical cut gear at end of cutter head (inside the gear box); that can be damaged. Often planer still operates, but tends to growl. After an accident like that, would crack open the gear box and inspect for damage. At a minimum, change oil and check for metal.

Question is do you guys think this type of head will decrease the future stresses on the casting repairs, ya know many of small cuts instead 3 big impacts from the straight knives. - Barkley

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IDK. How often are you going to run metal through your planer? lol

Carbide is more brittle than tool steel, and carbide will shatter if it sees shock load. But the chip clearance on segmented carbide head is smaller than straight knife, so it's might be easier to jam up the head?
Supposedly the straight head requires less HP, as it stores kinetic energy between cuts; while the segmented head are constantly milling wood. Both heads have same available HP, but in a crash situation; a straight knife head would have more energy.

Looking at the the quick change head gib configuration .vs. a regular straight blade head; am curious if the same damage would have happened with regular straight knife head? Have had knots unexpectedly pop out that jam and stop a cutter head, start burning the belt, even damage the helical drive gear once; and never had cracked head casting. What ever happened to that machine to crack cast iron head, must have been very loud, and would have been an 'fresh underwear required' event.

Best Luck.

The crack was on the oppisite side from the gear box. It's on the inside corner where the thinner front casting meets the thick side castings. I have pictures, trying to upload. I'll check the gear you were talking about.
I'll bet the damage was caused by a knot.

LOL Was expecting much worse damage?

IMHO - that crack is not worth fixing. It's not in an important area. That cast iron web's purpose is to support the chip deflector (you have a chip deflector, right?), and is thinnest portion of back cross bar. The reason the cracked stopped is web gets much thicker towards the back side of casting.

I'd drill a small hole at very end of crack to prevent it reaching the tapped hole for chip deflector, and ignore it.

If a chunk of metal is missing on underside, fill area smooth with JB Weld to improve flow of chips around cutter head. Be sure to abrade with a carbide burr, de-grease to remove excess carbon from cast iron surface before applying JB Weld.

The labor required to strip the head and remove it from machine for welding is couple hours. Takes 2x as long to reassemble. Reassembly can take 5X longer your first time doing it, as have learn how to reset the parallelism of head to table, and adjust the raising chain under the base.

Since the drilled hole will be directly over the out feed roller, would be safest to remove the entire roller before drilling or working in area?
Lower the table. Stack 3-4" of wood under roller, and raise table. Pull drive chain cover. Rotate the chain tensioner out of way. Remove the gears/chain as one assembly. Remove the feed roller tension springs from top. Remove the bolts holding the feed roller underneath casting, and the out feed roller and bushings land on support blocks. Lower table another 1", and can slide feed roller out the way. Easy Peasy 5-10 minute removal.

Check the feed roller bushings for wear, while it is disassembled. The bushings are supposed to be manually oiled every XX hours of use. Based on machines I have seen; it's mostly ignored maintenance.

PS - That crack location is not going to see any different stress between a straight knife cutter head, or segmented cutter head. Only stress in that area is; when you crash the head on a knot.

Best Luck.