Archive for ◊ July, 2014 ◊

• Thursday, July 31st, 2014

Hammer A3-31

Having established in the previous post a rationale for this type of machine in a small woodshop, let’s take a look at the Hammer A3-31, which I’ve been using for the past two and a half years.

Getting it into the shop

I’m afraid I must start with one of the few problems I have experienced with the A3-31: getting it into my shop. The mobility kit uses a single axle that attaches to the base parallel to the 55″ jointer bed, along with 4″ wheels that simply turn in one plane – they do not swivel. A lifting bar is inserted into a cleat near the bottom of the base of the machine to roll it in a straight line and make partial J turns.

The top photo shows the lifting bar in place. One wheel is visible at the lower right of the machine base.

The system works well in the shop but it will not get the machine through the 32″ doorways in my house or the 36″ doorway of my shop. To make matters worse, the A3-31 was shipped on a pallet built for a special narrow-fork pallet jack. I ended up having to transfer the machine from the pallet onto a dolly that I built and use plywood sheets to get it over doorway bumps – a big hassle. If you have a garage shop or other wide doorway, all of this is not a problem.

To solve this problem, I wonder if Hammer could include a short axle to attach to the base perpendicular to the jointer bed to be used with a matching cleat. It might work only with the jointer beds raised but that would be good enough to just get the machine through narrow doors. Hey, Hammer: this would help many small shop woodworkers.

Now on to happy issues.

In order of frequency, here are the most common concerns among woodworkers that I’ve heard and read about j-p combo machines:

1. Changing between jointing and planing modes.

Fuhgeddaboudit. To go from jointing to planing, the fence stays in place. You lift the jointer beds as a unit, then flip the dust hood and reattach the hose. The tables remain parallel when raised so the effective width of the machine is approximately unchanged. The planer bed is cranked into position with an extremely smooth and fast mechanism. The jointer beds return to position precisely. Really, it’s all fast and easy.

Here are the beds lifted:

Hammer A#-31

And here the dust hood is in place for planing with the hose attached:

Hammer A3-31

This is the planer infeed with the bed raised into place. The adjustment mechanism has the helpful, optional “digital handwheel.”

Hammer A3-31

2. Jointer bed length

Is a 55″ jointer bed long enough? It sure is for anything I do. I have no problem routinely accurately jointing rough boards 6′ long. In my opinion, there is no need to have the entire board length supported on either the infeed or outfeed table to do accurate jointing.

If you want more length, Hammer offers optional extensions for jointing and planing that look like they attach very easily.

Hammer A3-31

3. Dust collection

Can the dust hood contraption really work in both jointer and planer modes? Yes! The A3-31 is nearly perfect when used with my Oneida Mini Gorilla cyclone collector. It is the tidiest machine I’ve ever used.

4. Accuracy

Can a combination machine be as accurate as single function machines? This was my number one concern when contemplating the purchase.

For a given quality level, having used the Inca for many years, and now the Hammer, I say the answer is yes. I did have to do considerable work tuning the A3-31 to my liking but I’m a rather fastidious worker. (“Really, Rob? You? Get outta here, I wouldn’t have imagined . . .”) The key is that this machine can be tuned and it holds the settings. More on this in a future post.

5. Power and mass

Are these machines, in this size range, just toys for dilettantes? OK, now I’m getting a little annoyed. Just fuhgeddaboudit, OK? The motor is listed at 14 amps/220V and does not balk at planing full width boards. The mass of the beds, the quiet operation, and the results it produces are real deal.

[This extended review of the A3-31 and the general topic of j-p combo machines are unsolicited and uncompensated.]

Next: getting inside the machine.

• Sunday, July 13th, 2014

hand jointing

In the previous post in this series, I recounted my stock preparation history culminating with the Hammer A3-31. Prior to discussing the ins and outs of the Hammer machine, let’s look at the rationale for a combination jointer-planer in the small shop.

I’m guessing most of us share the following woodworking profile. We have:

  • A strong desire to build things from wood that exceeds the desire to dawdle with woodworking tools.
  • Less time than we want for making things.
  • Less shop space than we’d like.
  • Less money than we want.

To get a pile of wood transformed into a finished project, the stuff needs to be taken to the desired thicknesses, with flat parallel surfaces and a straight, square edge before being ripped to width and crosscut.

Here are some options:

1. Handwork/hybrid

Doing it all by hand is just too slow and tedious for most of us, but a hybrid approach employing a portable thickness planer is very practical. One face is made flat but very rough using scrub and jack planes, just enough so it does not rock or distort on the planer bed, and there is no bow (lengthwise curve on the face). The planer flattens the opposite face, the board is then flipped and the planer makes the first face flat and parallel. Then hand plane a straight edge.

Don’t forget too that a well-tuned bandsaw with adequate blade height can do a pretty good job as a jointer and thicknesser followed by clean up with hand planes.

2. Exceptions

It does pay to be able to fully prepare a board entirely by hand just as a baseball player must be able to bunt – it isn’t used often but a complete player artfully brings up the skill when needed.

Some boards are too short to safely feed to a thickness planer and hand work is a must.

Also, there is an occasional board in which I want to preserve every hair’s breadth of thickness, and conservatively flattening one face by hand is a less risky method.

For very wide slabs, elaborate router jigs can be set up but finding a local commercial shop with a megabeast thickness sander makes more sense to me.

3. Separate jointer and planer machines

The big problem here is that jointers with widths that approach even inexpensive portable thickness planers are big and expensive. To me, it makes little sense in terms of expense, space, and work efficiency for most small shop furniture makers to have a $2000, 600-pound, 8″ jointer with a 7 foot bed paired with a 13″ thickness planer. Or how about 5 or 6 thou for a 900 pound 12″ jointer?

One interesting exception to this mismatch situation is Grizzly’s G0706 12″ jointer that has a 60″ bed.

4. Combination jointer-planer

In a single machine with a fairly small footprint, you get an excellent 12″ of planing and matching jointing capacity. This opens up a world of managing wide boards with ease. This is value.

There is a range of prices starting at about $1800 up to twice that, among options that include Rikon, Grizzly, Jet, Rojek, Minimax and Hammer. Pair one of these bad boys with a steel frame bandsaw with a matching 12″ capacity and life is very good.

Lower budget 10″ models are available, including Rikon, Jet, and Grizzly. I will say that I really appreciate the extra two inches and extra beefiness of my current Hammer over the 10″ Inca I had. Hey, how about 16″? Sure, if you’ve got the space and money, but for most of us it’s not necessary for most furniture making.

In the next post in this series, I’ll go into some detail about my Hammer A3-31. Previewing, here are two non-issues: bed length and change over between functions.

Hammer A#-31