Customer Reviews

Jet 708580 JBM-5 1/2 Horsepower Bench Mortiser

5 star:		(31)
4 star:		(26)
3 star:		(10)
2 star:		(5)
1 star:		(1)

 

 

If you utilize mortise and tenon joints and have been creating them with a router or a drill press with a mortising attachment, you will really enjoy this product. There are several positive attributes about this tool and one negative.

Positive Attributes:
1) HP is quite adequate.
2) The chisels and bits I received were very sharp. They believe that they would serve the non-professional well. I usually use Clico bits, but I recommend that you at least try these before you purchase an expensive set. You might be as pleasantly suprised as I was and you could save yourself some money.
3) Fit and finish is very good.
4) The column mounts to the base structure with capscrews. The Jet engineers were thinking, because they provided two assembly hole patterns. The second hole pattern allows you to turn the head around 180 degrees. This will enable you to mortise stock one or two inches taller than normal designed capacity without a major setup changes.
5) Good quality for the price.

One Negative attribute:
If you have read any of the reviews of mortise machines, you will notice a common issue with bench top mortise machines is the hold down fixture. Jet is considered to have one of the better hold down fixtures. If you have used drill press with a mortise attachment you have lived the pain of setup and hold down. This machine is by far a huge improvement over a drill press attachment. However, this hold down fixture could also be improved. Mine is not parallel with the base surface or square with the back fence. This allows the stock to rack slightly when withdrawing the chisel from the mortise. It doesn't take much movement of the wood to bind the chisel in the mortise.

Note:
I am upgrading to the Powermatics floor model because of the improved hold down, the translating table, and the larger chisel capacity. I am very happy with my Jet mortiser and do regret purchasing it. I just want more.

Operator errors to avoid:
A) If you try force the chisel and bit, you run the risk of elevating the temperature of your cutting tools and ruining the temper. Try to keep the wood from smoking.
B) If you force the cut faster than the helix on the bit can remove the chips, you can induce too much heat into the cutting tools and could stall the motor.
C) The HP is fine. If the wood is smoking, slow down.
D) Lastly, it seems too obvious, but be prepared to mount this to a table or some other ridgid structure before use.

After having used biscuit joiners, dowels, and hand-made mortise and tenon furniture, I decided to invest in a powered benchtop mortising machine. After seeing and using various brands, I found the JET JBM-5 to be the best designed and most precisely built of the lot. The machining, design, simplicity of use are the best available for the novice-to-advanced woodworker. The hold-down bracket is designed to clamp evenly and the depth stop is easily adjusted without tools, unlike the Delta model. Another useful feature is the unit can be reversed on its base, allowing mortising of long objects--I built a clamping devise on the back of my mortising stand and can accomodate 36" long material for end-mortises or wide stock. The 2 year warranty should be more than adequate, given the history of other JET tools I've used--all running prefectly as designed.

I have a Delta drill press and had used a mortising attachment for several years. It is quite difficult and time consuming to set up. I had wanted a dedicated mortiser and decided to try the Jet, and boy am I pleased. Basically, right out of the box you are ready to make great mortises. I attached it to an auxilliary table as described in the manual and began work. I am building an antique pie safe and am using very hard red oak lumber. The Jet tooled through the red oak like cutting through butter. I especially like the slow speed (1750 RPM) that the drill bit turns. You are assured that you will not burn the wood. The chisels are also incredibly sharp. I found it easy to set the work fence to center the work piece and properly setting the cutting depth adjustment is a breeze. All in all, a very fine tool. Very glad I bought it!

I purchased the JBM-5 for a woodworking project that used 120 mortise & tenon joints. The machine itself appears very solid but there were a couple of finish problems. First, the spring-return chuck door on the left was not aligned with its recess. Second, the fence was not perpendicular to the base and required some shimming.

There are some other annonyances, too. First, all of the chisel & bit sets still had rough machine marks and burrs on them. It took a lot of time and patience with a small file to get them into useable shape. Second, after the packing oils wear off, these chisels scream like a kicked cat until they come into contact with wood. Jet needs to find a better OEM for their chisel & bit sets (as Delta had with the Austrian chisel & bit sets included with their benchtop mortiser).

The adjustable fence is poorly designed (a problem that seems common to all benchtop mortisers save the Powermatic). Depth adjustment is poor, requiring a Zen-like concentration to adjust it to a precise depth. Also, the fence is, at the same time, too short for taller pieces (4"+ in height) and too tall for short pieces (which require shims to reach the hold-down on the fence). The ability to rotate the motor 180 deg to mortise taller pieces is definitely a nice feature. However, Jet did not provide any way for pieces to be supported in this configuration (I had to build a jig for this).

In all, the JBM-5 performs as advertised. However, all the little annoyances add up quickly. It still beats a drill press with a mortising attachment (or forstner bits), but there is definitely some room for improvement here.

I have been woodworking for several years. I have made mortises by hand, with a Delta drill press with mortising attachments, and with a router and jigs. I really wanted a Mutliquip or Powermatic mortiser. But since I am very pleased with the several JET products I own, I decided to purchase the JET mortiser, which costs considerably less. I have now found a better, faster (and cheaper) way of making mortises with JET's JBM-5 benchtop mortiser.

Hand-made mortises (w/ a chisel) are cleaner than machine made mortises, but take time and practice to acheive superior results. I have made many mortises with the JET using the bits that were included that are good and acceptable for most of my projects. My mortises got even better since I began using Clico mortising bits instead of the bits that come with the mortiser.

On the down side, first, the control lever has about 1.5" of play. While this is annoying, it does not detract from the quality of the mortise. JET could engineer the gears a little tighter to remove the play. Second, the cast base plate was cracked, probably in shipping. This seems to be a common problem, since the replacement was back-ordered and took 3 weeks to get. JET could prevent this problem by shipping the base plate and motor support detached.

On the upside, the instruction manual is clear and concise, assembly took 15 minutes, the mortiser's fit and finish are excellent, the mortiser is easy to set up and use, and JET's customer service rep. answered my call on the second ring and in 5 minutes, my order for a replacement base plate was processed.

While the Multiquip and Powermatic mortiser's are more expensive and provide greater adjustments, the JET mortiser is a good tool and much less expensive. I'll spend my savings on wood.

Happy Woodworking!

I purchased this machine after reviewing several articles and stopping at a woodworking store for a first hand look. As a professional woodworker I was looking for a machine with a low cost and good quality. This machine fit the bill. It is not, however: without a few drawbacks that are easily remedied. First of all the fence isn't parallel to the chisel, and the table and fence are not square to one other. The remedy was to shim the post mounting base. To accomplish this I loosened all three cap screws then visited the kitchen and got a sheet of aluminum foil. I cut strips about two inches wide and six inches long, folded them in half to one inch, and lengthwise to about two inches. I put eight to ten of these under the front of the base and pushed them back till they contacted the two front cap screws. Tighten all screws and check for parallel between the fence and chisel. Add or remove shims until the desired relationship is obtained. Check the chisel for squareness with the table at ninety degree from the fence as well to make sure you aren't changing that relationship (shim one side or the other as appropriate to get this plane in alignment as needed). Once the fence and chisel are in alignment the fence will be square to the table. Once this is done the foil that is hanging out from the post is easily cut away with a sharp knife to keep things neat. The unit tends to twist to the left slightly when the first cut is started, and by tightening the two screws on the left this is minimized. Be careful not to tighten too much as the force required to move the unit will be increased as will the wear, and be sure to keep things lubricated. A gentle touch when initiating the first cut keeps movement to the left to a negligable. The chisels are "okay",and they come with the machine; but a little time spent fine tuning their edge and polishing the outsides is worthwhile. The drills tend to lack adequate clearance behind the cutting edge which is easily filed or ground away to prevent it from rubbing annoyingly against the chisel. The unit cut mortises beautifully after these few adjustments. It's first task was eighty four mortises for slats in a crib of hard maple. The cuts were clean and accurate, the crib ends required a mortise with a two inch depth as a radius was to be cut on the pieces later. Having squared the chisel to the fence and table made the job much more accurate and the work easier. The chisel cut and released much easier now traveling parallel. There are better after market bits available, but for someone who wants consistency and speed for short production runs, or can afford the luxury of this machine in a home shop the machine and it's chisels are winners when adjusted properly. The elongated chuck wrench allows for changing bits without bandaids for your knuckles, and there are doors to the chuck on both sides of the machine. There is even an adapter for 3/4" chisel and bit should you find the need. You must find your own chisel though. The table top is pressed board which is up to the task, and is easily changed to what ever you might desire in it's place. With the machine trued I had no problem keeping stock against the fence for consistent mortises. The tensioning apparatus for the fence is adequate, The plunge arm is fixed in it's attachment, and probably would be handier if movable, but the same relationship can be maintained by adding height to the table with blocking if you are so inclined. When secured to a solid table use is much more enjoyable. It requires a lot of force to do the job, (which is made easier for the user by the leverage that the arm provides) but it is still great torque at the point of attachment and if the base isn't secured to something immovable the work is difficult at best.

There are many features that I really enjoy with this machine. First the fact that I do not have to also purchase the bits. The bits have worked fine for me and I have used them on some oak and hard maple. The extended chuck key provent me from busting my knuckles on the casting. Lastly I like the slower speed because the bits do not burn near as easily as on other machines I have used.

I bought the JBM-5... because I wanted to make mission-style furniture, with lots of mortises for the decorative slats. This tool made short work of lots and lots of square (and rectangular) holes. It was trivially easy to set up - just bolt the stand to a work table, bolt the riser tube to the stand, and put in the return spring. If you have ever cut mortises by hand you know it takes a while. With this unit the slowest part of the operation is positioning the workpiece. In this regard the provided fence is not very helpful and accounts for some of the 4-star rating. There's no fine adjustment on this (or most competing) mortiser's fence. All it does is insure the piece stays parallel to the chisel's sides, but it's a little challenging to get the fenceto exactly the right place. And the hold-down did not reach down to the 1" height of one workpiece so I had to boost it up with some scrap. The cut itself was pretty good, but I wound up cleaning up some of the mortises with a chisel. (Not nearly as much work as cleaning them after drilling round holes, though.) The bottoms of the mortises are nowhere near flat, with the circular mark from the drill part a bit lower than the center of the walls and higher than the corners. However since these will generally be hidden by the tenon it's not a problem unless you are only allowing a very thin (less than 1/4 inch) wall at the bottom. A nice feature is that the base has six holes and the riser has three. This allows you to turn the unit around to mortise taller workpieces or use your own vise. You could mount your drill press vise on the back side to hold pieces that didn't fit in the provided hold-down. Best features: 1. Long shank chuck key and doors on both sides makes changing bits a snap. 2. Lever arm is long enough for real power, and angle is easily adjustable. Improvements to get 5 stars: Replace the fence and hold-down with a vise - preferably one with XY positioning like many machine shops use.

This the first Jet tool I bought and own when I started making this mission style bedframe (On cover of Jeff Miller's Beds) about 6 months ago. Because this tool, I bought two more Jet tools so far (650 dust collector and the 6" jointer). This mortiser is everything I wanted to do with mortise. I made 132 mortises for the slats on the bedframe that turned out beautifully. I am making two matching nightstands and a mission style coffee table. The three chisel bits come with the machine along worth more than $100. I looked at other mortisers before buying this one, they all require you to buy extra things to get started. The setup was easy, changing bits was a snap as well. I mounted the mortiser on a piece of thick plywood siting on top of my workbench. When I had to work on thick stocks (6-7"), I just took out the three mounting screws and rotated 180 degrees. That gives me another inch or so distance from the plywood base. It makes very clean cut. But sometimes it sounds pretty lound if the bit rubs the chisel, and you have to clean the dust fast enough to avoid burning when making deep cuts.

Ok so I have spent the last 2 days with my new jet mortiser and I Love It. After having purchased the jet MF17" drill press which came with the mortising attachment and torturing myself with setting that thing up every time I needed a square hole cut, this machine is a Dream come true. setup was done in under 10 min, i glanced at the manual once to identify only one funny metal part, the rest went together purely by intuition =) fit and finish was perfect, not a dent or scratch on it, i did manage to stall it a few times in some oak, but I was using my old 3/8" chisel that came with my drill press, (time to sharpen that thing) i put a new sharp chisel in and it was like cutting warm cheese. but everything else is perfect. I love this machine! Oh and one other thing I did take a good long look at the delta mortiser and was disappointed in the quality of that unit. The fence was crooked, the depth stop needed a hand tool to adjust, and its finish seemed mediocre, it did not come with the long neck chuck key needed to use these machines.. I have been a long time delta supporter but I think they have dropped the ball on this one.