8" Frankenjointer

[Mark Bolton]

We have an 8" jointer that a guy dropped of at our shop some time ago. I call it the frankenjointer because the head and tables have been bolted to a homemade angle iron frame, it had a 3/4HP motor attached to the angle iron frame with a single V belt about 2 sizes too long running from the motor to the cutter shaft. The slack in this belt allowed the motor to slip until the head came up to speed. Surprisingly it worked pretty well. I thought it would lose a lot of RPM when feeding a board but it didnt.

It has been parked for a while but I am in the process of fabricating a new enclosed stand for the jointer and refurbishing it. It has very short tables, no longer than a typical 6" (Jet, Rikon, Delta) with a simple but decent fence. I am not sure how smooth I will be able to get the table adjust but even if I can get this thing runnning and dialed in to 1/32" and lock it it would be a handy addition to the shop.

Question, do I really need something like a 3HP motor on this jointer for light passes like 1/32"? Could I get away with a 1 1/2 or 2 HP? Also, it seems cutter head speeds of 5K+ RPMs what I should shoot for, thoughts? I had thought of switching to a double sheave on the motor and cutter as long as I have enough shaft on the cutter. I havent checked the tail length on the cutter shaft.

I was thinking a 3450RPM motor with 1:1.5 ratio up giving me 5175RPM if thats an appropriate speed.

Thanks for any input,
Mark

[CPeter James]

I have a Delta DJ20 8" jointer it came from the factory with a 1 1/2 hp motor. Prior to that I had another Delta 8" jointer that had a 1 hp motor on it. The 1 hp was ok, but slightly underpowered, but the 1 1/2 hp is fine and anything in the 1 1/2 to 2 hp range should be fine. Head speed should be in the 5,000 rpm area to give 15,000 cuts per minute. 3 hp would be overkill unless you happened on one cheap.

CPeter

[Mark Bolton]

Thanks for the info. I had just scanned a couple grizzly models and saw the three hp. Our 6" has a 1.5hp and wasnt sure.

Will see what I can find,
Mark

[Chip Lindley]

Your instincts are right on track. Unless you are jointing 8" widths regularly, a 1hp motor would be plenty for this machine. As CPeter said, our DJ20 8 inches came with only a 1.5hp motor. Plenty of Power. If you have a 1 or 1.5hp motor handy, use it!

1.5 X the 3450 motor speed is plenty of RPMs also. Right on again! Enjoy the old hunk of CI!

[Kevin Looker]

I'd check the cutterhead before I try spinning it at 5,000 rpm.

It is a modern gibbed type head?

Are the knives totally secure?

Are the bearings up for the task?

Are there any cracks in the head?

I read in another forum of a guy having a jointer head come apart on him. He wasn't hurt but it did a lot of damage not to mention scaring the hell out of him.

[Mark Bolton]

Kevin,
I have absolutely thought of that stuff, your fears are mine as well. The bearings are 1" bore pillow block style. While they have a very slight growl there is absolutely no slop or end play. The head is identical to the others I have in my shop and havent seen any cracks though that doesnt mean their couldnt be one. By gibbed I am assuming you mean like the ways on a machined dovetail using bolts/plate for retention.

When this jointer was initially dropped off I went over it quickly without tearing it apart. We ran it quite a bit but without having the time to refurbish we just parked it in the corner. I am confident that it is fine and other than the possible cracked head I will pay close attention putting it back together.

I surely dont want to run the risk of any tool like this coming apart. Even though I have swapped out knives in my planers probably hundreds of times its like one of those OCD things where I am constantly wondering if I tightened all the bolts. Overly cautious, go over them three times, etc.

Perhaps I will post some pictures when I get it apart.

Mark