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JMR Tubing Notcher Product Review

Published by Trails Less Traveled on November 1st, 2006

 

Introduction

cheapo holesaw notcher=
It’s a shame that the JMR tubing notcher has to be labeled a holesaw notcher, because it’s NOTHING like the cheap holesaw notchers that most of you are probably familiar with. In fact, forget that you’ve ever seen a holesaw notcher before. As an exercise in design, the JMR tubing notcher is a complete success. The craftsmanship and quality is evident in every feature and detail. The only downside is that you’ll pay top dollar for it. At almost $600, this thing is expensive (for a holesaw notcher). But set that fact aside for just a minute. It’s not as hard to justify the expense after taking a closer look at it.

JMR holesaw notcher=
The pivot location is probably the most distinguishing feature of this tubing notcher. It was thoughtfully placed at the intersection where the holesaw and material meet, so you don’t have to reposition the material to change notch angles. This might seem like a small detail, but it makes all the difference in the world when you’re actually using it.

massive shaft=
It’s designed to be powered by any 1/2” drill and the massive 1.125” induction hardened holesaw shaft ELIMINATES deflection. Seriously. You can notch a piece of tubing and then move it over as little of a 1/16” and re-notch the tubing instead of wallowing into the first cut. The additional rigidity also makes holesaws seem to last forever. I’ve made literally hundreds of notches with the first holesaw blade that I purchased for it and haven’t come close to wearing it out yet.

Timken bearings=
The holesaw shaft rides on high-quality sealed Timken bearings that run in an open oil bath. I’ve been using this notcher frequently for the past eight months and I haven’t seen the slightest hint of contamination or wear.

allen-head set-screw=
The holesaw blade is threaded onto an allen set-screw, which is nice for two reasons. First, it’s cheap and easy to replace if the threads get damaged. Second, it makes removing a jammed holesaw blade as easy as popping the set-screw loose with an allen wrench.

degree markings=
The engraved degree markings (set at 2.5-degree intervals) are an excellent example of the level of quality found throughout this tool. JMR claims their notcher is capable of notching tubing within a 210-degree arch, and technically that’s true, but there are still some practical limits; you’ll end up being limited by the length of the hole-saw shaft. The range of angles that this tool can notch is still pretty incredible though, especially considering that most holesaw-type notchers can only notch up to about a 55-degree angle.

Timken thrust bearings=
A Timken thrust bearing increases clamping force at the pivot while requiring less wrench pressure to tighten lock it down. This is really clever. It made perfect sense when Jim explained it to me, but I’d never seen anything like this before. The thrust bearing under the bolt head makes it easy to turn with a wrench and concentrates all of the clamping forces between the two plates. I’ve found that it’s only necessary to snug this bolt down anyway, because you’re pushing directly into the pivot-point so it doesn’t really try to move around or change angles while you’re notching.

thrust-bearing washer= angle adjuster bolt=
The top frame-plate is tapped, so loosening/tightening the bolt to change angles is a one-tool/one-hand operation. Notice the quality of that custom-machined adjuster bolt. No standard hardware here. I don’t know if everyone appreciates these details, but this is what you’re paying for.

tubing clamp=
The machined aluminum clamp has a 2.5” round tubing capacity and can hold square material on the flats or on angle (corner-to-corner).

adjustable mounting points=
The clamp and holesaw shaft block are both bolted to the frame plates with four recessed allen bolts in sliding tracks. This allows the user to adjust where they’re bolted down, which is sometime necessary to make notches at extreme angles.

vise clamp detail= vise-mounted=
JMR sells an optional pedestal mount, but it’s important for me to keep things small and portable in our small shop, so I opted for the vise mount. I actually used the notcher in a vise for a while, but I decided that it would be even more versatile if I could mount it to a 2” receiver hitch.

receiver mount 1= receiver mount 2=
So I cut the end off an old receiver hitch with a Sawzall and tack-welded the JMR mounting block into place.

receiver mount 3 =
Then after checking to see that it was mounted straight and level, I welded it up.

receiver mount 4= receiver mount 5=
I kinda blew it when I was planning this though, and only realized afterward that I needed to access the bolts that hold the clamp to the frame-plate. So I notched the receiver with an angle grinder, but a little better planning would have made that unnecessary.

receiver mount 6=
Anyway, it’s worked out great. I’m planning to add more receivers around my shop, under most of the tables and workbenches. In the meantime, it’s just hanging off the Hanson Enterprise bumper on the back of our CJ7. I still need to add some type of set-screw to keep the receivers from vibrating in the hitches. It’s not a problem when I’m notching tubing, but gets pretty annoying when I’m using a Sawzall or a grinder.

Milwaukee V28 drill=
I’ve been using a 1/2” Milwaukee V28 cordless drill to operate the JMR notcher. I’m not usually a big fan of cordless tools in a shop environment, but like the JMR holesaw notcher, this is another exception to the rule. It’s no Hole Hawg, but it’s got plenty of power and the battery life is surprisingly good.

drilling for upper shock mount= finished upper shock mount=
You can also clamp the JMR notcher to a piece of tubing to drill holes. When I needed to relocate the rear shock mounts on our Tacoma, I used the JMR notcher to drill the holes for these tubular Camburg shock mounts.

offset notching=
One feature the JMR notcher lacks is the ability make quick/easy adjustments for offset notches. Oh, you can do it, but it involves removing four allen bolts and shimming the holesaw shaft block. I had to dig around my shop for a while one afternoon just to find some washers that would stack to the height I needed. It worked fine, but it’s not ideal. When I asked Jim at JMR about this, he just replied that he didn’t consider it an important enough feature to include. Fair enough, but it would be nice.

EDIT: I just learned that JMR now offers shim kits. These machined aluminum plates are 1/16, 1/8, 3/16 & 1/4” and can be used in any combination to achieve the desired offset. I haven’t used them, but it sounds like a step in the right direction. What I like even better is the upgrade that JMR is working on that will allow users to adjust the offset without removing any hardware. I understand this will be available as an option when purchasing a new JMR notcher and will also be sold separately as an upgrade for older notchers.

holesaw bottomed-out=
Our cuts are still limited by the depth of the hole-saw blades and on really deep notches, the holesaw will bottom-out before it completes the cut. Most of the time I can just break the piece off with a pair of channel-lock pliers and keep going, but sometimes I have to grab the angle grinder and hit it with the cutoff wheel. Stay tuned though, because Van Sant Ent. is rumored to be working with a holesaw manufacturer to develop a new line of longer/deeper holesaws specifically for this type of fab work.

compound bend 1= compound bend 2=
This is one of the few examples of a notch that a JMR notcher actually can’t make. To be fair, nothing short of a messy abrasive belt sander notcher, CNC mill or a laser cutter would be able to notch compound bends on tubing (where a bent tube needs to be notched to fit another bent tube on a different plane).

Quick Tips

sawzall cut=
Cut your material to length first with something like a Sawzall or a chop saw. It’s much quicker and easier to notch tubing when you’re only removing half of the material from the hole.

cut marks on tubing=
Leave it a little long. Take it slow, mark your cuts and remember that it’s easier to go back and trim a little more than start over.

tubing clamped in JMR notcher=
The JMR notcher is a really convenient place to cutting material to length, clean tubing before bending, make funky notches with an angle grinder and prep/clean material before final fitment and welding, etc.

transferring cut marks between pieces=
Whenever I need to make more than one of something, I use the first part I complete as a template. It’s easy to transfer those measurements over to the next piece and saves a LOT of time.

pipemaster 1=
I picked-up a set of these PipeMasters in assorted sizes and I use them all the time, especially when I need to mate tube to an irregular surface or join several tubes together at the same junction.

pipemaster 2= pipemaster=
I was able to slip this 1.75” PipeMaster right over the material I needed to cut and transferred the cut line with a silver marker pen. Whatever method I’m using to notch tubing, these little tools are useful when I’m scratching my head and trying to figure out where to cut.

This Article was originally published on Off-Road.com September 2006

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