PowerPro Headstock Review, 2015

[sehast]

Since the main reason I got the PowerPro Upgrade was for the improvement in table saw performance that is what I will review first. I began with making some run out measurements on the spindle, saw arbor and finally at the edge of the saw blades. The new quill and main drive produced a round out error of .001” or less when fully retracted and was able to maintain that tolerance while being extended all the way out to 4.5”. I think that is very good when compared to other tools that I own. My table router has an error of about .001” and my Mini Mill can hold it down to .0005” while my CNC water cooled spindle has a negligible run out error of .00016”. But they are all driven directly with the motor and don’t have anything like the extendable quill. Next I measured the saw arbor run out at .003” which was consistent for both the 5/8” and the 1 1-4” arbors. I don’t have a cabinet saw for comparison but the specs are consistent with these measurements and my Makita miter saw showed the same .003” error. Lastly at the edge of the blade I measured a .006” error. That was consistent for both the Woodworker II thin kerf (3/32”) 40 tooth blade with a 1¼” arbor and the Freud 80 tooth 1/8” blade with a 5/8” arbor that I tested. My miter saw with a 1” arbor and 12” blade showed the same .006”. I was a little bit surprised because I thought the 1¼ “ and 1” arbors would have held the error at the edge of the blade to a tighter tolerance but not so. My conclusion here is that in general saw blades produce a kerf .012” larger that the thickness of the blade assuming you have both the miter slot and fence perfectly aligned.
For the operational testing I used 2” thick beech about 6” wide that had been jointed on one side and one of the edges. I also did some cuts on 2” oak and maple but the beech was used on my last project when I struggled to make rips and crosscuts with my old 510. Also beech is more prone to burning than maple or oak making it a more severe test. Ripping the 2” beech bogged down my 510 using the Woodworker II so much that I had to come to a stop halfway through the cut and then just crawl to complete it. The burn marks and edge it left were not pretty. The crosscut also using the WW II was equally challenging but left a little better edge. I didn’t even try the 80 tooth Freud blade on the 510.
The performance of the PowerPro was great. I used 3450 RPM throughout the test. The rip went very quick even through a couple of knots with WW II and I couldn’t tell any change in the motor throughout the cut, it just smoothly plowed ahead. There were no burn marks and the edge was close in quality to the jointed edge. I was never able to feed that fast on the 510 even on ¾” stock. I did a couple of crosscuts with ease. Next up was the 80 tooth Freud blade for some crosscuts. Due to its greater thickness, 1/8 “ and double the number of teeth, I was expecting to see a big difference. I fed the 2” beech at about the same rate as with the WW II and the PowerPro didn’t flinch. It left an even higher quality edge with no burns. About the only thing I was able to use the Freud with on my 510 was plywood. I then crosscut a few pieces of 2” maple and oak just to re-confirm performance and they cut just as easily as the beech.
I would have to say that the PowerPro exceeded my expectations in the table saw department. I am convinced that this upgraded headstock will have all the power I will need as a table saw on my projects. I checked for how hot the Idler and Drive shafts got after this hour or so test. I found them to be only slightly warm and similar to my old 510 after such a session. Also I was on the lookout for belt slippage during those heavy cuts but saw none. I will cover drilling in the next post.

[charlese]

Good review, sehast! Not surprising, but thorough. You must be an engineer.

About any future slippage - I talked with Shopsmith's engineering about the recommendation you got for 1/4" belt deflection. The answer I got said you should have been told 1/8".

As said earlier, my belt deflection is set at <1/8", but equal.

[sehast]

I suspected as much. Anyway I finally found the source of my rattle last night while I was running down another issue. When setting up for sawing I noticed that when I slid the headstock up against the stop ring and carriage the saw blade was off center on my table. It is about 3/32" right of center of the table insert. My 510 had been perfectly aligned before the upgrade. I inspected the quill, took it out and re-tensioned it. After I did that all the chatter and rattles went away. I must have had the tension set too low. Now I plan to tighten up the belts to where I had them before I got the bad advice from Shopsmith. I sure appreciate you following up on this.

Do you have any idea where this 3/32" offset is coming from? Its like the new spindle is longer. The quill is fully retracting up against the bumper ring and the spindle collar is set firmly against the bearing. I already sold the old quill so I don't have it to compare.

[algale]

Just realigning the table to the blade can cause the blade to be other than dead center of the insert if one does not take special care to ensure both alignment and centering. It will effect nothing but can be annoying if you have OCD.

[dusty]

I suspected as much. Anyway I finally found the source of my rattle last night while I was running down another issue. When setting up for sawing I noticed that when I slid the headstock up against the stop ring and carriage the saw blade was off center on my table. It is about 3/32" right of center of the table insert. My 510 had been perfectly aligned before the upgrade. I inspected the quill, took it out and re-tensioned it. After I did that all the chatter and rattles went away. I must have had the tension set too low. Now I plan to tighten up the belts to where I had them before I got the bad advice from Shopsmith. I sure appreciate you following up on this.

Do you have any idea where this 3/32" offset is coming from? Its like the new spindle is longer. The quill is fully retracting up against the bumper ring and the spindle collar is set firmly against the bearing. I already sold the old quill so I don't have it to compare.

I do!. I normally (no longer) do not comment much about the accuracy of the Shopsmith. I seriously doubt that you have anything wrong with the hardware in your Mark V setup. All you have to do is pay close attention to each and every tiny detail while you are setting up and aligning. Little things like the arbor not fully seated onto the shaft or the quill not fully retracted each and every time you make one of these measurements. The headstock not located, with respect to the carriage, in with the same separation. I doubt spindle installation but maybe, a tiny maybe.

[JPG]

I assume you have thought of this, but I have to ask, are the arbors the same?

I also assume you have not done a table alignment since acquiring the PP stuff.

If so, that leaves the quill body, the stop bumper, the stop ring, the knurled 'knob' and the quill shaft. All that is 'new'.

So, what is the distance from the headstock face of the stop bumper and the outer face of the knurled 'knob'? I bet it is 3/32" further than your old quill. I would suspect the quill stop bumper was shrunk. I be assuming a new quill stop bumper is what you now have.

Do I understand correctly that increased return spring tension cured the 'rattle'? Question remains why did that make it go away? Is there end play in the quill shaft? Is the quill body 'loose' in the headstock bore?

I realize I asked more questions and no 'answers'. Hopefully they lead you to some answers. Strictly shot gunning possibilities.

[sehast]

Hi JPM,

All assumptions are correct except I have the same stop ring because it was not part of the upgrade kit. I don't have the old quill to measure but the difference has to be between the stop bumper and the spindle collar. The arbors fit up against the collar. I am not going to worry about it, maybe as you say the new stop ring is just that much thicker. I will just use a stop ring that's 3/32" wider, everything else seems to be working fine.

[JPG]

The stop ring I was referring to is the 'o-ring' around the quill body that butts against the rubber ring. I neglected to include the distance from that ring to the outer end of the quill body and the gap between it and the knurled knob.

[sehast]

Drilling & Sanding Review

I will be reviewing the drilling and disc sanding functions in this post. I first made run out checks on standard drill chuck as well as the new 5/8” Keyless Chuck. The standard chuck was good as expected with a .003” run out error on both the chuck and on the shaft of the drill bit. The new keyless chuck I just recently purchased, however, was very poor. I measured over .006” on the arbor and .010 to .015” on the drill shaft. The keyless chuck is very solid and heavily made with a very smooth and effective hand tightening mechanism. At a price of $130 I was expecting the same quality and accuracy as the South Bend keyless chuck on my mini mill but that was not the case, at least for the one they sent me. I promptly returned it for a refund. I don’t know what I was thinking when I ordered it, the standard chuck is plenty good enough for woodworking.
I knew from the beginning that I was not going to find much improvement over the 510 for the drilling that I commonly do. The largest forstner bit I own and use is 1 3/8”. The PowerPro speed tables are very good at giving a recommended RPM for the size and type of bit. The speed recommended for a 1 3/8” forstner is 450 RPM in hardwood. I drilled a hole at 450 RPM in hard maple and it turned out fine. I then used 700 RPM, the lowest speed on my 510 and couldn’t tell any difference. I am sure if you were using a 2 or 3 inch bit, it would be a completely different story. The only real advantage I see is the access to the speed table. With the 510 I usually just tried C and if it seemed to work I used it, if not I selected B or D. Now I can be very precise the first time.
I use the conical sanding disc a fair amount as an alternative to a planer on figured woods and on pieces too large or too unwieldy for the planer. The only difference I see on the PowerPro is the very constant speed and a feeling of better stability than the 510. Also is the addition of the speed table recommendations is a nice touch but not as useful as for drilling.
Overall, I would not upgrade to the PowerPro solely for drilling or sanding operations unless you need to use large diameter forstner bits. I don’t do any lathe work so I won’t review that function but I certainly see the advantages of speeds below 700 RPM for turning. Also I don’t have any Shopsmith special purpose tools. I did try my biscuit jointer which I use a lot and it worked fine but not much different than it did on the 510.
That is pretty much it for this post. Next will be routing and shaping.

[dusty]

Hi JPM,

All assumptions are correct except I have the same stop ring because it was not part of the upgrade kit. I don't have the old quill to measure but the difference has to be between the stop bumper and the spindle collar. The arbors fit up against the collar. I am not going to worry about it, maybe as you say the new stop ring is just that much thicker. I will just use a stop ring that's 3/32" wider, everything else seems to be working fine.

That tiny deviation could very easily come from table alignment.

Just loosen all four bolts that secure the table to the trunnions and do a table alignment again. Be particularly picky while doing the alignment and you can get it near dead on.

Curious coincidence? The typical Shopsmith saw blade is 3/32" thick.

A peek at my table alignment tool.
http://www.shopsmith.com/ss_forum/viewtopic.php?t=10868