Double Spindle Shapers Explained

Double spindle shapers: how they work, what they're good for. February 15, 2009

I've seen a couple of the old double spindle shapers for sale locally recently, for very little money. Having never used one I wonder what the advantage is of having two spindles on a single machine over two separate machines? I've been tempted to go check one out, but I'd like to know what the reasoning was behind them first. It seems like maybe they're a thing of the past as I haven't seen any new ones.

Just for some insight, I currently run three shapers with both 3/4" and 1-1/4" spindles. I believe there's no such thing as too many shapers. Though if I were to buy one of these big suckers I'd likely get rid of at least one of the three to make room.

Forum Responses
(Solid Wood Machining Forum)
From contributor R:
They have counter rotating spindles, when pattern shaping this allows mounting identical cutters and thus the ability to cut always with the grain, reducing tearout.

From contributor M:
I agree with everything contributor R said plus they usually don't have fences and they don't have miter slots milled in the tables.

From the original questioner:
Thanks guys, so they're more specialized than I had thought. I don't think I'll be needing a setup for that type of work. Then again two separate motors means I could swap a couple wires and have them rotating in the same direction, but probably just as well with multiple shapers.

From contributor R:
“Then again two separate motors means I could swap a couple wires and have them rotating in the same direction.” Bad idea. On many of these, the spindles are screwed on to the arbor, the threads would be handed if I'm not mistaken, so you wouldn't want to reverse the rotation. Besides that is an advantage to one of these machines, to be able to mount a cutter in either direction.

From contributor P:
Those big old monsters often have interchangeable spindle caps. They often utilize a steep machine taper and a internal drawbolt or cap screw of sort. One screw in RH threaded and the other LH threaded. I have an old Oliver single spindle and have worked on a few old doubles. Sometimes the caps were keyed to the spindles, this will prevent them from coming apart. I have seen were someone has drilled and tapped a set screw. It’s probably not the best idea as it will affect the balance. You really have to dig into the particular machine to see how it is constructed. If I had the space, I would have several doubles.

From the original questioner:
I hadn't even thought about that scenario. Owning all single spindle machines, I might not have realized the spindles were threaded in until it was too late. Contributor P - room is always an issue but I figure widthwise it's not much bigger than two of my separates next to each other. The extra depth shouldn't be too much of a problem.

That said, what do you consider the advantages to the double spindle? I really haven't gotten to the point where I do any pattern shaping using two of the same cutters, so that wouldn't be an advantage, at least at this time. I can reverse the cutter rotation on any of my shapers already so that's not really an advantage. I guess this is one of those situations where experience helps. Sometimes you just have to use a certain machine to understand its usefulness and potential.

From contributor M:
Besides being used in the furniture industry, double spindle shapers were used in pattern and model shops. There would be a ring in the table insert that matched the OD of the cutterhead. Many times these heads would be 5-6" in diameter and stand 24" tall, ungaurded. Parts would be shaped off templates and it was important to have spindles turning in different directions to account for grain direction.

Try shaping something 24" tall off of a template sometime. They used to be nicknamed the widow maker. Even with large angles holding the piece square to the table so it wouldn't tip into the spindle, people still stopped what they were doing to watch when someone fired up the shaper. Needless to say you had a test run first to make sure everything would clear before going for it. The heads screwed on just as contributor R said, at least on the Newman Whitney I worked with.

From contributor C:
The 24" high spindles were found in the old automobile body shops. My furniture people usually had 6" or 7" detachable spindles. I would only have one additional comment, since I am a peddler. A Whitney double runs so much smoother than any other shaper that I fail to see why everyone would not want one.

I used to walk through the shaper department of large plants on late Friday afternoon when they were running some overtime and in a shaper department that might have a couple of Whitney's, a Porter, a Greenlee and maybe something else, the lone operator would always be running the Whitney. When asked why, he would always say "because the spindles run better".

I would want a 91 because with the belt drive you get a commercial motor that can be replaced immediately in the event of a burn out. But with the advent of AC Varidrive controls, I have seen some really good applications on the older 134's which were originally manufactured for high frequency. If you find a good Whitney, you will not live long enough to wear it out.

From contributor K:
One thing you could do with this shaper if you are building your own cabinet doors is to get matching cutter heads in clockwise and counterclockwise rotations for your coping process. Run all of your sticking profiles in bulk lineal footage, crosscut to length, then cope each end respective of its rotation.

From the original questioner:
As usual you guys are providing some great information. I have to say the idea of a 24" high spindle purring along with some beast of a cutterhead really gives me the willies. I guess you'd kind of have to work your way up to that one.

Although my original plan when I started thinking about a double, I don't think the idea of running the copes and sticks on one would be practical for me. Since the spindles are turning opposite, I would have to buy two sets of each profile I use, which quickly would far exceed the cost of a second shaper.

I think after all I've read from you guys I'm going to concentrate on just upgrading the shapers I have with beefier singles and leave the doubles to the big boys. Now if I could find a Whitney single spindle for a bottom feeder price.

From contributor O:
That double spindle idea of KRC’s reminds me of a setup a local cabinet door shop used here in the early 80’s. He bought a bunch of the baby Delta 1/2" spindle shapers (I think they were about $400 back then and don’t know if the even make those anymore). He bolted these together in pairs with the miter groves between the shafts. Built a sliding plywood table to fit between the shafts and had left and right cope cutters on each pair for the different door profiles. The shafts were far enough apart to cope one end, and then flip the piece and do the other with pre moulded cut to length rails. For mullions and divided lites you would go in a little on one head then flip the piece to the other head.
It was low tech but it got him off to a start. They now have all CNC equipment.

From contributor K:
I have to agree with you about not running two coping shapers. I actually have a Powermatic set of three shapers which they were marketing in the late 80's - early 90's they called "Accu-door system”. Two of the three shapers had not only forward and reverse on them but a spindle design I think they called a powerstack.

The spindle is equipped with an air cylinder under it and with the turn of a keyed switch it would raise or lower the spindle. The idea is to have a matched set of clockwise and counterclockwise cutters on the spindle at the same time. You would run the sticking through one shaper in mass and cut to length as I mentioned above, then go the coping machine and run all the right hand ends then all the left hand ends just by raising or lowering the spindle. I have never used it this way because it doesn't allow for straightening the stock while profiling. As you pointed out contributor J, it presents a problem cutting copes after making the sticking cut on mid-rails and mid-stiles. These shapers are just modified 5h.p. model 26's and I love them! You can find model 26's a lot more often than you will a Whitney.

From the original questioner:
Contributor K it’s funny you should say that, because one of my shapers is a brand spanking new 5hp Powermatic 27, and unfortunately I'm not that impressed with it. Not sure what the difference is between the 27 and 26 models but mine has had several small issues already. For me though the biggest annoyance is vibration. It's not a major amount like there's something wrong, it's just not as smooth running as some of the bigger machines I've seen. For the money they sell for I feel like it should be a little higher quality.

I also have an 02' 3 hp Delta that is underpowered and unimpressive, except for a very decent fence. And lastly a Lin-Mac offshore brand 3 hp tilting spindle from the late seventies or early eighties. Which I have to say is the smoothest running of the lot. It's designed more like the early American shapers with a heavy cast iron pedestal bottom and a substantial CI top as well.

I think my goal is going to be to replace the Delta and Powermatic with either older American or newer Italian machines. My thought with this post was to use a double spindle to replace the two, but now I have a slightly better understanding of the double and I'm probably better off just upgrading the singles I have.

I do have to say the air cylinder idea sounds very cool. I have thought about stacking both sets of cutters on the spindle together to save time. But that change at the turn of a knob would really cut changeover times down.

From contributor K:
Sorry to hear you’re not happy with the PM 27. I will never disagree that the older and heavier cast iron machines are better! But, I have had good success with my Powermatic machines. In fact as I look around my shop 7 out of 15 major machines are Powermatic. That said, if I had more money I would not hesitate to upgrade to Northfield and others for any of them. I recently read in one post here in WOODWEB where someone talked about a Martin shaper. I was curious since I have never seen one so I went to their website. That is a top of the line machine with well thought out features! Obviously out of my price range for now but I enjoy machines and look forward to planning to upgrade whenever I can. I view each of my machines as a means to the next step up. I hope your 27 has been good enough to help you move up to that next level.

From contributor L:
You can still buy new double spindle machines and for left/right shaping on the same part they are much better than two shapers. You can buy a good used shaper for about the same price as a new Powermatic. We've got nine shapers, most set up to do one or two operations. Two of them change over by just dropping an auxiliary table over the cast iron to change ht. We used to have a Whitney with a feed sprocket that drove a pattern that carried the work past the cutter. We just installed a used Gomad tilt spindle, runs good (2050 lbs!) Machines we have that are good: SAC, SCM, Moak, BMT, Gomad. I'd love to have a Martin or SCM Vanguard but $50K is too much considering all the other things that are on the wish list.