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Posted: Tue Jul 09, 2013 8:37 pm
by dusty
joshh wrote:I wonder if a small computer-style fan could be mounted to the access hole and force air out. They make them in all sizes, some of which would probably be a perfect fit.



Something like this:
Image
Would a fan installed in the headstock change the dynamics of heating/overheating? Certainly it would but I don't believe that modification should be made by the user.

If overheating is an issue, Shopsmith should declare it so and proceed to resolve that issue immediately.

There should be no shelter in the fact that very few users are likely to operate at those heat producing speeds for extended periods of time.

Posted: Tue Jul 09, 2013 8:46 pm
by algale
dusty wrote:Would a fan installed in the headstock change the dynamics of heating/overheating? Certainly it would but I don't believe that modification should be made by the user.

If overheating is an issue, Shopsmith should declare it so and proceed to resolve that issue immediately.

There should be no shelter in the fact that very few users are likely to operate at those heat producing speeds for extended periods of time.
I completely agree with Dusty. I would add the modifying a Mark 7 will likely void the warranty.

Posted: Tue Jul 09, 2013 8:51 pm
by reible
I have yet to experience the auto shut down with my powerpro.

For one thing it is not likely that I will be doing much if any routing when it is 90 degrees or more. I have and do work in the mid 80 degree but only if I feel need to. Most times when it get to be mid 80's I just quit for a while, especially if the sawdust is sticking to my arms.

I have had limited use of the powerpro as a router. Most operations I tend to do are not going to have it running for any extended time. I still prefer to use a router for router operations with further reduces my router time on the powerpro. Things like the lack of a good fence system and table inserts are also an issue. It was not my intent when purchasing the powerpro as a router system and since shopsmith has done next to nothing to make it more router friendly I'm not so sure how committed they are to that function.

I would say that the long period of usage for me would be sanding and lathe work, neither of which requires the high end speeds. I have to say that even those times I would be limiting my time on the machine to compensate for boredom and keeping my concentration so I can work safely. If my mind starts to wonder off what I'm doing it is time to stop doing that and take take a detour.

In the past I believe the standard for determine machine usage was for every 10 hours in the shop you would be running the machine for 1 hour. That of course is quite general and may have changed over time but it does give a since of time on and time off the machine.

If you are thinking of cooling your powerpro think positive ventilation, getting clean air in and exhausting the hot air. Do not blow dust into your headstock so for that don't suck it in either. However it is quite possible to make things worse by doing anything. Too much air flow could actually make things worse by trapping air in small eddy flows. The flowing inside the headstock is pretty much an unknown so the best course of option is to probably leave it alone.

The last point I want to make is that if the powerpro design is to auto shut down at a set temperature then that temperature should be set to protect the components. Having it shut down should not effect the life of the machine as it is protecting itself. If left to keep going it would come to temperatures which would be stressful and possibly damaging to components. In most cases the part most likely to fail will be capacitors, especially electrolytic ones....

Ed

Just dropping by....

Posted: Tue Jul 09, 2013 10:09 pm
by riot_nrrd
Long time no chat. Saw this thread... I sometimes run my PowerPro pretty hard for the things it does well. It has gotten hot after ripping 6/4 stock for an hour or so, but I have not run into this error yet.

HOWEVER, I also don't use my ShopSmith as a router. When I want a router, i use one of three dedicated routers I have - a dewalt variable speed plunge, a dewalt fixed speed, or a craftsman variable speed mounted in my router table.

Can you use the PowerPro as a router? Sure. But should you expect it to act like a 23000 rpm machine desiged to do routing exclusively, and run it for half a hour non-stop? I think that might be asking a lot.

I love my PowerPro. It was a great investment. It is great system as a table saw, drill press, lathe, horizontal borer, disc sander, grinder, and belt sander, among other things. I would not be too harsh about it only being a "decent" router.

Posted: Tue Jul 09, 2013 10:18 pm
by joshh
Wise words :)

After reading your posts, I agree that any "correction" of this issue should come from shopsmith (if any is actually needed).

Posted: Wed Jul 10, 2013 12:25 am
by billmayo
dusty wrote:Would a fan installed in the headstock change the dynamics of heating/overheating? Certainly it would but I don't believe that modification should be made by the user.

If overheating is an issue, Shopsmith should declare it so and proceed to resolve that issue immediately.

There should be no shelter in the fact that very few users are likely to operate at those heat producing speeds for extended periods of time.
When I was playing with DC motors and controllers, I had major heating problems in the Mark V headstock. I adapted a 4" 115 VAC box fan to fit over the LOGO cover hole. I found forcing the air into the headstock did a lot to reduce the heating problem. Forcing the air out did little for the heat. I was using the 4" round louvered cover to protect the fan. I found I did not need the fan on the regular Mark V headstock. I found just using the louver cover provided quite a different in heat and reduced the internal dirt, sawdust and crud collection on the Mark V. I would not believe using a louver cover should not affect the warranty. I still have the box fan and louver cover in my cabinet.

Posted: Wed Jul 10, 2013 8:13 pm
by charlese
I know this thread is about heat issues, but other more positive characteristics of the PowerPro should be mentioned here. Although the PowerPro will over heat when pressed into service at the highest speed for more than 15 minutes, there are several characteristics of that power head that make it a jewel to use.

First: It is a very simple machine to shut down. When running at 10,000 RPM a simple pressing of the off button between cuts will certainly lesson heat buildup. I really don't know how effective this will be when routing a big job, but a simple occasional shut down seems like a good idea. In my practice, I shut down even between each rip or cross cut. (just for safety) The power switch stays on - it is only required to push two buttons to start sawing again. ("Start" and "Confirm") There is no reason to keep the headstock running when not working.

Next: The reverse function is very handy at times. With the bandsaw mounted on one end and a sander on the other, it is a simple operation to just slide the headstock from one end to the other and select "Reverse" for the appropriate SPT.

Also: The "Chart" function is extremely handy for whatever operation is needed.

Also: The increased power is appreciated especially when ripping. At other times the power is not noticed, but the SMOOTH QUIET running is!

Posted: Thu Jul 11, 2013 9:59 am
by Ed in Tampa
charlese wrote:I know this thread is about heat issues, but other more positive characteristics of the PowerPro should be mentioned here. Although the PowerPro will over heat when pressed into service at the highest speed for more than 15 minutes, there are several characteristics of that power head that make it a jewel to use.

First: It is a very simple machine to shut down. When running at 10,000 RPM a simple pressing of the off button between cuts will certainly lesson heat buildup. I really don't know how effective this will be when routing a big job, but a simple occasional shut down seems like a good idea. In my practice, I shut down even between each rip or cross cut. (just for safety) The power switch stays on - it is only required to push two buttons to start sawing again. ("Start" and "Confirm") There is no reason to keep the headstock running when not working.

Next: The reverse function is very handy at times. With the bandsaw mounted on one end and a sander on the other, it is a simple operation to just slide the headstock from one end to the other and select "Reverse" for the appropriate SPT.

Also: The "Chart" function is extremely handy for whatever operation is needed.

Also: The increased power is appreciated especially when ripping. At other times the power is not noticed, but the SMOOTH QUIET running is!

A motor is stressed the most when it is turned on. A continuously ran motor if properly cooled should last the longest. Also most motors draw their max amperage on startup so any cooling problems should be accentuated by an off on cycle.

If this issue does exist and SS can't or won't do anything about it, they should at least issue a warning to users and add a stipulation of the fact in sales material.

I know I would be a little more than ticked off if I have bought a Power Pro intending to utilize it at the max stated RPM for some purpose that took longer than 15 minutes to complete and found I could not do it.

Buy most air compressors and they clearly state the motor is not a continous run motor and that compressor will get extremely hot and should be allowed to cool down.

I think on the last compressor I bought it had a warning something to the effect of do not run it more than 20 or 30 minutes in an hour. So you could run it 10 minutes let it cool 10 and run it another 10 and so on. Or you could run it 30 minutes and let it cool 30.

Posted: Thu Jul 11, 2013 11:50 am
by fredsheldon
My concern about installing any type of air moving device would be the introduction of dust inside the housing which might be forced into the electronics of the motor and controller. I would think SS installed the fins on the motor housing to help remove excessive heat without having to force dust into the mix. Now if you could design some type of heat transfer device like a heat exchanger which would move the heat from the inside to the outside of the housing without introducing dirty air you might have something.

Posted: Thu Jul 11, 2013 3:11 pm
by nuhobby
Ed in Tampa wrote:A motor is stressed the most when it is turned on. A continuously ran motor if properly cooled should last the longest. Also most motors draw their max amperage on startup so any cooling problems should be accentuated by an off on cycle.
This is true generally, but an electronic Soft Start, as the PowerPro offers, seems like it would greatly reduce that stress.

I turn my PowerPro on and off all the time. It's a finessed experience, no hard switch-clacks, and no dimmed lights.