The JointAbility


John's Tool Crib
by John Cupp

The latest press release

The JointAbility
A review by John Cupp

THE Wood Jointing Tool For Boat Builders

(Photos provided by RB Industries)

Greetings my fellow boat builders and read about one of the most innovative tools I have seen in the last 20 years. I love building boats, and not all of them can be under eight feet in length. As I perused a kit of information pamphlets mailed to me by a wood working group, I noticed a tool called the JointAbility on the postcard sized advertisements. It stated I could mail this card in and get a large information packet with a video for free (it cost me postage). A few weeks later the packet arrived with the video in my mailbox. After opening the packet and watching the video I had to review this very special tool. A more appropriate word could be "cutting jig" but it was much more. I called the manufacturer, RB Industries (RBI) and spoke with a company representative to make arrangements to get the large unit delivered to my door. The box was nearly seven feet long and deceivingly narrow for such a great tool.

Most of you know what a jointer is usually used for but for those who may not, it is commonly used to make an unfinished board of wood have a nice straight flat side or sides for further wood working. It is essential that a board have at least one straight side in order to square the rest of it. That is what the JointAbility does but with a tool both reasonably priced and light in weight. You can even take lumber that still has tree bark on both sides and make dimensional lumber for boat building. This tool allows you to seamlessly join plywood together, butted end to end or lengthwise side to side. To do this you need a handheld circular saw, a router and a spiral router bit. For mounting to the circular saw, RBI makes a bracket that requires two holes drilled into the bottom shoe.

I decided that for its inexpensive price, a Ryobi circular saw would be perfect for permanently mounting the bracket. I will be using it for years to come. I made a trip to Home Depot and picked up the Ryobi saw for about thirty dollars and mounted the kit on it. That saved my good hypoid saw the indignation of drilling holes in it and mounting and demounting with the required setup measurements.

I purchased the spiral ½” router bit at a tool supply store but RBI has them in stock and they are less expensive. With oak at the maximum thickness, my 1 ½hp router could not pull the load. I found using my Ryobi 2hp plunge router a better choice. It also has a micro adjustment needed to scarph two plywood sheets together using my method of ½” overlaps.

Now the JointAbility has two sizes. A 96” version for the boat builder and a 60” version for making furniture or smaller boats. I decided to try a sample of 5.2mm Luan joined together. It has 3 plys with the middle being the largest and strongest. I set my circular saw to cut to the exact middle of the center ply ½” from the end. I then set the router to the same dimension and I had half of my joint ready. I took another piece of Luan and did the exact same thing to it. I then epoxied both pieces together. I let them cure for a day. I then set one end on a concrete block and tried to break the Luan plywood. It broke, of course, but nowhere near the seam I made with the JointAbility. I switched to ½” seven ply fir plywood and it didn’t break. The plywood lamination held, even after the eighth or ninth try, which is more than the effect on my already crippled bones and joints. If it wasn’t for the small amount of epoxy at the joint you couldn’t tell where the seam was.

When making the seam, place plastic wrap on the bottom of the JointAbility . Then place the plywood and epoxy joint inside the JointAbility and add more plastic wrap. Clamp the joint while it cures. I had some 2 ½” X 12” pine from an old waterbed, so I ran it through the planer to take off all the dark stain. I then put the pieces in the JointAbility and trued up the edges like a jointer is supposed to do but without tear-out and snipe. I placed two bar clamps across the pine and cranked on the pressure but the pieces never bowed up or down because the JointAbility makes exactly square edges on the lumber. They also have a handy router holster to safely place your router so it won’t interfere with what you are doing until you need it again.

RB Industries produced it's first piece of woodworking equipment in 1929 as a contract manufacturer for the old Belsaw Company. From 1929 until 1980 they made all of Belsaw's wood planers and various other woodworking accessories. In 1980 they designed and patented what is currently known as the Universal Wood Planer System which allows the owner to remove the cutter head from the machine and replace it with either a molding assembly, sanding assembly, or a gang sawing assembly. This new design was offered to the then Foley-Belsaw company to market and they decided against it, so they worked out a plan to cut ties to them and went out under their own name with the new design. --RB Industries

A large cast iron jointer could cost over a thousand dollars and take eight men and a boy to move it. Just a month before testing this machine I had the opportunity to buy a used jointer that was not at all cherry for $600 and I thought it would be a good deal but I got there as another buyer was loading it.

Here is even some better news! The JointAbility is on sale right now and the smaller 60” unit that is normally $299. Is now $229. And the 96” unit that I used is now $329. Instead of $399. I suggest everyone get the router holster for $49.00 and the saw guide assembly that bolts onto your circular saw. You absolutely need the saw guide, but the router holster can be bought at a later time. I bought the router bit at Western Tool Supply for a whole lot more than the same bit from RBI which costs only $39.00. I suggest you buy the bit from RBI.

According to their website, 80% of JointAbility buyers already have a jointer! You cannot get better surface from any jointer than you get with using the JointAbility. I almost fell over myself when they told me the JointAbility has a 5 year warranty. Even a novice can make accurate glue joints the first and every time with this tool.

I have seen some very ugly fiberglass joints on boats made with multiple sheets of plywood. With the JointAbility the seams fit together so tightly they are nearly undetectable. You can even make large flat panels like I did with the old waterbed frame. I looks like someone cut off a 6’ wide slab of yellow pine. I may use that for my chart table in my next cruiser, but I know I will forever be hooked on the JointAbility. It is built of steel that is powder coated to a mirror finish and with a long piece of double laminated Melamine. The best part is it is built right here in the USA.

It can also be used for cutting an ultra smooth cut on plywood edges. A planer cuts at 6,000 rpm but the router you use to smooth the cuts on the JointAbility is turning at approximately 24,000 rpm. Angle cuts are also no problem and if it is a soft substance like UHMW you can also make a smooth finish. I tried it but I can’t say anyone at the RBI factory has tried it. It worked for me.

If you plan at anytime to join together wood or plywood do yourself a favor and buy a JointAbility. You will never regret the purchase and with it’s heavy-duty construction you should own it for many years. I’ll be using the JointAbility on my next boat and the next and the next after that one. When you are done using it you can stand it up in a corner of your workshop so it is not in the way.

If you do end up buying a JointAbility, tell them that you read about it here. Their phone number at RBI/Hawk Tools is 800-487-2623 the fax number is 816-884-2463. The web address is With a Hawk credit card you can pay an affordable $25.00 a month for the 96” JointAbility.

The JointAbility is a tool you use as a yardstick to compare other tools by with its time after time perfect performance. I am very happy that I tested this tool’s capabilities because the manufacturer has hit a grand slam home run. I can find no faults other than my total captivation of thinking of other useful ways to use it. If you build boats of any length, do yourself a favor and send for the information. It has improved my plywood joints assuring perfection with each joint. Although not impossible, mistakes are very hard to make using this tool. It also makes it easy to improve your boat building.

From my Tool Crib to yours,