I have a Powermatic shaper, 3HP, with a 3/4 spindle.

I'm wondering if it is appropriate to use a molding head of this type on that machine:

enter image description here

The molding head will fit a 3/4" spindle/arbor. I can think of a few potential issues... one is the rotation speed. The shaper has a few speed settings so this may be OK. The second is the motor HP. This type of molding head seems meant for a radial arm saw, most of which would not be 3 HP. On the other hand they are also meant for table saws which certainly can be.

  • "THIS SPACE RESERVED FOR EXTRA CUTTERS" Wow that gave me flashbacks to the early 90s and looking at IBM mainframe manuals with their "This page left intentionally blank" notices on every (otherwise) blank page!
    – FreeMan
    Sep 23, 2020 at 16:28
  • What is the lowest speed you can run your shaper at? Sep 26, 2020 at 17:45
  • (and as a PS, even running one of these on a tablesaw scared me...) Sep 26, 2020 at 17:49

1 Answer 1


I'm not sure how well this will qualify as an answer as I have never tried to use mine on a 3hp shaper. I only wished to make a brief comment but it seems I don't have the rep points to leave comments yet. There's a safety concern involved so I hope the community will forgive me reaching out in the only way available to me.

I have what appears to be the same tool and mine was indeed made for the table saw. The body of mine is solid cast iron and when loaded with cutters, is very heavy. I only used it on the saw a couple of times but never felt safe standing in front of that much rotating mass. My saw's speed is about 3400 rpm. The tool was rated at a slightly higher max rpm, I remember, but nothing near a real shaper's speeds.

I stopped using it because I gained access to a relative's traditional shaper. This brings me to another point. With what I learned about using a shaper, I can see no way mine would have safely worked laying horizontally on a shaper spindle. In my case it would have involved major alterations to the fence or making a custom fence.

Either way, I just wanted to caution you about trying to run it on a traditional shaper at shaper-like speeds. I always felt my contraption was unsafe at any speed and would never considered using it on a real shaper.

(edited for grammar)

  • 2
    +1. I feel this is about as good an Answer as the OP could have hoped to get. As with so many Qs here there's often no "This tells us X not Y". Also, while you could have gained the necessary rep easily, you'd have struggled to fit this lot into a Comment!
    – Graphus
    Sep 24, 2020 at 7:11
  • @Graphus Thanks, I feel better knowing it was not seen as some illegitimate end run. I was sincere in wishing to get the OP my "really bad feeling" about using it on a shaper. Also, lol. I know about the length not fitting in comment space. I guess it was just seeing all that blank writing space that made me so windy. While I have 45+ years of good woodworking experience, I'm still hesitant on professing an opinion in public. Just not the way I came up. Thanks again. I may need to work harder on being concise.
    – Jim
    Sep 24, 2020 at 10:05
  • @Jim frankly a fair number of answers here are opinion based. I think that's because we get a fair number of "is this safe" type of questions. While there are some things that are clearly not safe to do, there are a fair number of operations that can be performed safely if you understand the risks, but can be exceedingly dangerous if one isn't extremely cautions. TL;DR: don't be afraid to express your opinions - 45 years is a lot of experience and will be very valuable to the community! Oh, and don't worry about an excess of words, either - maybe learn to lead with a summary [con't]
    – FreeMan
    Sep 24, 2020 at 13:56
  • ... then get into the details, but, sometimes it takes a lot of words to get the point across. ;)
    – FreeMan
    Sep 24, 2020 at 13:57
  • 1
    You don't have to worry about denting or breaking the rules [on this] here, Woodworking simply isn't busy enough for there to be enough care :-) Plus policing of minor transgressions like this isn't a high priority site-wide anyway (from what I understand, I exclusively post on Woodworking and only read some other parts of SE occasionally). Bottom line is, get a feel for how the Comments are used by seeing how other users have and continue to respond to Qs and you won't go far wrong.
    – Graphus
    Sep 25, 2020 at 17:50

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.