delta jointer
The just-arrived Shelix cutterhead waiting to be installed in my old faithful DJ-20.


1 September 2017

I knew the carbide knives in my DJ-20 were nicked and dull and I also knew that I had a big maple project coming up, so I came to the proverbial cross-roads, the kind we all hate: Did I want to purchase a new set of carbide knives and then go through the ritual of installing them? A mental picture of a cat chasing its tail popped into my mind. I decided not to do that. Again. Or ever again, if I could help it I decided to take the plunge and upgrade my jointer to the SHELIX cutterhead.

Instantly, another mental 'video' popped onto the wide screen of my mind this one depicting paper money with wings flying out of my wallet. So be it. If I had been wise enough to have purchased a Shelix years back I would not be going through all of this and would probably be money ahead. That matters not now. I took the plunge and feel much better for it, especially now that it is already installed and has been fully tested. Picture your author with a huge smile on his mug.

I'm getting ahead of myself, so let's back up a bit. The following is a list of the subjects that we will be covering in this upgrade. The blue arrows following each article will pop you back up to the top of this page.

Jointer Installation Preparation

red-finger incon

Disconnect your machine from its power source!

The following upgrade and alignment procedure is my way of getting the job done. I have no doubt that others have accomplished this same process in less time and with better results. Let good common sense be your guide.

Once you have your machine safely unplugged, it is time to remove the fence and its support, the cutterhead guard and the rabbeting ledge. You must also lower the infeed/outfeed tables as low as they will go. You will probably have to back out the positive stop screws of both tables to get both lowered as far as possible. See following image.

To remove the belt from the pulley you need to remove the back plate and force the belt off of the lower pulley while rotating it. This done, it may be a good idea to grab your vac and do a little housekeeping inside your jointer. And blow out the inside of your motor if you have acces to an air compressor. This will help keep your motor cool.

jointer outfeed table positive stop screws
This image shows the outfeed table positive stop screws. The right screw needs to be backed out sufficiently to allow the table to be lowered to its lowest position.

I have found that it is a good idea to replace each screw or bolt back into the jointer base from where it was removed. If you do this it will not get misplaced and will be exactly where it should be when you need it.

The following two images should provide a visual clue as to what the lowest table setting should look like with regards to the position of each tables table shaft. This applies only to a DJ-20, of course.

This image shows the infeed table table-shaft at lowest setting.
This image shows the outfeed table table-shaft at its lowest setting .

cutterhead Removal

With both tables lowered as far as they can go, your cutterhead should be now be completely exposed ready for removal. At this point do not be tempted to remove the belt pulley before you continue. With it in place, it is easier to remove the cutterhead as it provides good surface area for you to grip when you lift the cutterhead out. Now remove the four 6mm bearing block screws which hold the cutterhead in place. They have lock washers so be sure not to loose those when you lift out the screws.

This image shows the bearing-block screws removed. Also note that the infeed and outfeed tables have not been lowered down as far as they should be to enable the removal of the cutterhead.

I found that prying up the non-pulley bearing block with a screwdriver helps to get your fingers under it as the next image shows.

This image shows the recess beneath the operator-side bearing-block. A screwdriver can easily be used to pry up the bearing-block sufficiently to get your fingers under it for a secure grip.

With the long screws removed, grip the cutterhead and gently lift it out. The bearing blocks fit very snugly in the jointer base so lift up as vertically as you can. If the cutterhead makes contact with either of your tables this means that your tables are not as low as they should be. Make this correction and try again.

This image shows the infeed and outfeed table inboard-edges lined up with the outer edges of the removed bearing blocks. With both tables in this position, the cutterhead can be lifted out vertically very easily.

I have read that someone who performed this upgrade had to remove some of the cutterhead knives before they could lift out the cutterhead. That told me that they probably did not have the infeed/outfeed tables lowered as far down as they would go. I did not have this problem.

Disassemble The Delta Cutterhead

Your old jointer cutterhead has been removed and now you have a few things to do to proceed. First of all, you need to remove the pulley. With the cutterhead resting on the bearing blocks, remove the pulley retaining screw and gently tap off the pulley with a block of wood and hammer while rotating the cutterhead. Rotating the pulley as you tap keeps the pulley aligned as it is being tapped off.

This image shows the retaining screw removed from the pulley.
The tapped off pulley and its key.

With the pulley now off the cutterhead, place the screw, pulley and the key in a safe place. You will need these again in short order.

Now we need to remove the bearing blocks. Using gentle taps with a plastic tipped hammer, I tapped each bearing block while rotating it. It took more than a few taps, but they finally came off.

This image shows the operator-side bearing-block removed from the cutterhead.
The pulley-end bearing-block has now been safely removed. Surprise! We now have a snap-ring to contend with.

Just when you think you're on a roll, reality strikes. The snap-ring was staring me in the face. I thought I was prepared with a set of new snap-ring pliers, but I was wrong. They did not open far enough.

Luckily for me, I found an ancient pair of snap-ring pliers from another world and Voila!, they worked. There were more than a few epithets slung about my shop, but in the end, I prevailed. To be honest, I was not certain that I might encounter a snap-ring, but I purchased a pair of snap-ring pliers just in case. I am very grateful that I had that old pair in my tool box because they saved the day.

Sucess! The snap-ring has been removed.

I ordered my Shelix with new bearings installed. When I opened the box I noted that a new bearing was still in its box. This surprised me, but now I know why it was not installed as expected - it was due to the snap-ring!!

Okay, the snap-ring has been removed now we have to remove the old bearing from the bearing-block.

This image shows the large dowel I used to tap out the old bearing.

As shown in the above image, I supported the bearing-block on both sides of the bearing opening and used a large dowel to tap out the bearing using gentle hammer taps.

The bearing has been removed. Great!

Okay, the old cutterhead has be completely disassembled, now it's time to get the SHELIX ready for installation.

Prepping the SHELIX Cutterhead

Now we need to install the new bearing and both bearing-blocks on the SHELIX cutterhead. I used a paper towel soaked with alcohol to clean each bearing seat before I installed the bearing and each bearing block.

This image shows the operator-side bearing-block being installed over the pre-installed bearing.

At this point I began to wonder how far over the bearings the bearing-blocks should be installed. The answer to that question soon revealed itself to me.

I now installed the uninstalled bearing into its bearing block (using the large dowel) and reinstalled its snap-ring. This was followed by reinstalling the pulley side bearing block as shown in the next image.

Here I am using the shipping carton block of wood to tap on the pulley-side bearing block.

Well, that was not too difficult. The SHELIX cutterhead is now ready to be installed back into the jointer.

Installing the SHELIX Cutterhead

With both bearing blocks installed, I placed the new cutterhead assembly back in the jointer base to see how things were lining up. If I could not install the long bearing-block screws, I removed the cutterhead and drove the bearing-block(s) further over the bearings until I was able to thread the screws into the jointer frame.

At some point while doing this, one of the SHELIX outermost cutters (there are only two on the cutterhead) rubbed against the bearing block when I rotated it. It was obvious from this that I had to move the cutter away from the bearing-block to prevent this contact. I had apparently driven the bearing-block too far over the bearing.

Learing from this experience, I repositioned the cutterhead using a stout 1"x1"x10" (or so) piece of hardwood to tap the cutterhead while it was bolted in place. In so doing, the cutterhead was quickly centered on the jointer tables. The following two images show the outermost carbide knives.

This image shows the operator side outermost carbide knife. Note the distance of the outermost knife from the bearing block.
This image shows the pulley-side outermost carbide knife. Again - note the distance of the outermost knife from the bearing block.

This is not as complicated as it may sound. I just tapped the cutterhead very lightly while rotating the cutterhead. This was time consuming, but was not very difficult.

If the jointer had been completely reassembled this would not have been possible because the fence and the rabbeting-ledge would have prevented me from placing my hardwood stick against the cutterhead to tap it into position.

Voila! The new SHELIX cutterhead is installed.

Tighten down the four bearing-block screws very snugly and you're done with this phase of the upgrade.

Table Alignment Check

Before you reassemble your jointer, you must align your outfeed table against your new cutterhead. This is easier to do with all of the components uninstalled.

Raise your outfeed table up to where you think it is coplaner with your new SHELIX cutterhead knives. Do not lock it down just yet. Take the longest machined straightedge you have and lay it on your outfeed table and completely across the pulley-side outermost cutterhead knife. Rotate the cutterhead with the pulley (this will save your fingers from the cutters) and note whether or not it makes contact with the bottom of your straightedge. If not, raise the outfeed table very slightly and try again. Do this until the carbide knife just rubs against the straightedge. Now, repeat the same process with the outermost cutter on the opposite (operator) end of the cutterhead. Keep repeating this process - with both ends of the cutterhead - until they scrape against your straightedge very slightly.

If you are not able to do this with your current outfeed table alignment, then it would be my advice to realign your tables. This may not be what you want to hear (after all the work you have just done), but it really is necessary. Your outfeed table must be in alignment with your new cutterhead. And, in turn, your infeed table must be in alignment with your newly aligned outfeed table.

I am not going to go into that on this webpage because it is long enough as it is. I will add a link to this page when my table alignment webpage is completed.

Jointer Reassembly

With the SHELIX cutterhead installed and centered on the tables and your jointer tables newly aligned - if this was necessary, it is now time to put Humpty Dumpty back together again. This should not take very long.

Final Thoughts

It's easy to say that this upgrade was no big deal - AFTER the upgrade has been completed, that is. In truth, I did experience some apprehension, but I think that is only normal when you take on a challenge you have no previous experience with.

I consider my jointer to be the most important power tool in my shop. I say this because it creates the initial surface that all of my projects begin from. A jointer has to not only produce a perfectly flat surface on our boards, but it also has to contend with all the abrasive debris that rough wooden planks have embedded in them.

That said, I have always hated running rough lumber over my jointer because I knew that was going to dull the carbide knives quickly. In no time I would be changing out the dull carbide knives, installing fresh knives and then aligning each of them to the outfeed table. With the SHELIX installed, I no longer have to contend with any of that. All I will have to ever do is rotate the dull carbide knife/knives 90-degreees and tighten down. That process takes mere minutes for each carbide knife.

While the old cutterhead was out I discovered that neither of its bearings would rotate smoothly. I think it would have been just a matter of time and one or the other bearings would have gone out. I'm not so sure I would have even noticed this over the noise of the machine. I can only image all of the grief that would have caused me.

I no longer have to worry about this. And, speaking of bearings, I noticed that the bearings SHELIX provided were manufactured in Turkey. Whether that's good or bad, I have no idea at this time. What ever happend to Timken bearings? Gone down the tubes like every other American manufacturer? I have no idea.

Lastly, I positively LOVE the "swishing" noise that the SHELIX cutterhead makes as it flattens a board. I don't have a dB meter, but I guarantee that the SHELIX is MUCH quieter than the Delta cutterhead ever was. I was contemplating the purchase of a new link-belt to replace the original belt. I'm not so sure that will be necessary now.

Would I go through this SHELIX upgrade process again? In a heart-beat.