A Slower Speed Solution....new idea?

[paul heller]

OK, I must be tired or something. I reread it. "This guy" is "Dale" from the other group. Got it. Sorry!! I'll go back to bed now.

[backhertz]

This is getting more interesting. Why raise the bridge, when you can lower the river?

I made contact with another individual today, John. He too did a DC conversion. But he did it using a 1.5 hp Pacific Scientific DC motor and simply replaced the AC motor in the headstock. It is a pulse-width modulated motor simply controlled with a dial. The controller is mounted within the motor pan & BAM!: a DC controlled headstock.

There's a link on a knife forum which outlined a a process where a guy made his own DC motor controlled strip sander. Here is the link: http://www.bladeforums.com/forums/showt ... did=281333


So what would this cost? Using new parts would be expensive. Using used/surplus parts....maybe under $100.

The end result would be a double controlled headstock. Turn the main dial to where ever you want & then adjust the control knob to turn it to where you want. John no longer even turns his Shopsmith speed dial, but leaves it in one place.

So if any of you have treadmills in your exercise equipment grave yards, you might have the solution under your feet...
http://www.thestuccocompany.com/mainten ... 13522-.htm

Tony

[Ed in Tampa]

This is getting more interesting. Why raise the bridge, when you can lower the river?

I made contact with another individual today, John. He too did a DC conversion. But he did it using a 1.5 hp Pacific Scientific DC motor and simply replaced the AC motor in the headstock. It is a pulse-width modulated motor simply controlled with a dial. The controller is mounted within the motor pan & BAM!: a DC controlled headstock.

There's a link on a knife forum which outlined a a process where a guy made his own DC motor controlled strip sander. Here is the link: http://www.bladeforums.com/forums/showt ... did=281333


So what would this cost? Using new parts would be expensive. Using used/surplus parts....maybe under $100.

The end result would be a double controlled headstock. Turn the main dial to where ever you want & then adjust the control knob to turn it to where you want. John no longer even turns his Shopsmith speed dial, but leaves it in one place.

So if any of you have treadmills in your exercise equipment grave yards, you might have the solution under your feet...
http://www.thestuccocompany.com/mainten ... 13522-.htm

Tony

Tony is there any chance of getting some pictures of the conversion? I would really like to use a DC motor but I figured the conversion would so messy that I wouldn't want it on my SS.
Ed

[backhertz]

http://www.firechat.com/ssdc.htm

Isn't this a thing of beauty? I work with radar systems; little ones to very, very big ones. AC motors are a thing of the past. As newer systems are fielded, the huge drive motors have become smaller & smaller and DC controlled.

These pics on this thread are several years old. The parts came from a surplus outlet. The Shopsmith IMHO is relying on a very old design which could have been simply updated without all that much work. There is no reason why a digital speed readout wasn't incorporated in the 50th anniversary model. In my study of physics the principle of induction- resistance to change is manifest in many ways.

But I can not hammer Shopsmith very hard. The company has tried to incorporate change, but they hired a company that failed the number one rule my industrial engineer professor taught me and never let us forget: "if you want to improve any tool or process, always go to those people who know best: the people who make it & those who use it." The result is guaranteed to always be a good one for all concerned. But then the adage, "if it works, don't Blank with it often prevails." In the end, the companies who survive are those who, like Harley Davidson, make it a legend which keeps people like most of on this forum loyal to the company.

I know a wood master in his 90's. He could care less about AC or DC. He can/could use his eyes and his hands to make simple changes to make a so-so thing into a piece of art. However, he tells me he isn't as half as good as his father was being his father didn't have electricity, so he did everything by hand.

I guess it's all relative.

[paulmcohen]

This is getting more interesting. Why raise the bridge, when you can lower the river?

I made contact with another individual today, John. He too did a DC conversion. But he did it using a 1.5 hp Pacific Scientific DC motor and simply replaced the AC motor in the headstock. It is a pulse-width modulated motor simply controlled with a dial. The controller is mounted within the motor pan & BAM!: a DC controlled headstock.

There's a link on a knife forum which outlined a a process where a guy made his own DC motor controlled strip sander. Here is the link: http://www.bladeforums.com/forums/showthread.php?s=&threadid=281333


So what would this cost? Using new parts would be expensive. Using used/surplus parts....maybe under $100.

The end result would be a double controlled headstock. Turn the main dial to where ever you want & then adjust the control knob to turn it to where you want. John no longer even turns his Shopsmith speed dial, but leaves it in one place.

So if any of you have treadmills in your exercise equipment grave yards, you might have the solution under your feet...
http://www.thestuccocompany.com/maintenance/More-questions-about-my-DC-motor-213522-.htm

Tony

The links to the actual motor and electronics are all broken, this would be an interesting project to tackle, maybe with some help from Shopsmith we could design the next 530 a DC controlled Shopsmith with digital speed control.

With some volume we could get the upgrade to cost ~$400-$600 who would be seriously interested? I would make a link belt part of the upgrade as well. I think from what I have seen to get to 1.5 HP you need 230V AC input. I have found off the shelf controllers in dust proof enclosured for under $180 retail. The motor is still a question.

[backhertz]

http://www.garagejournal.com/forum/show ... hp?t=12817

There is another link. I've been emailing back & forth with John. He uses his DC modified Shopsmith every day and it is as powerful as he needs it to be. In fact, he believes it is faster than the original and it will go to 1 RPM with all the torque he needs.

The one thing I was not originally aware was the length of the drive shaft. John cut off the shaft from one side of the motor and screwed it onto the other side so the motor sheave could be attached. He simply tapped it & used a screw. I couldn't tell from the pic- it looked original.

I'm checking on some motors at the moment. Used treadmill motors seem to be used for many different purposes requiring a electronically controlled variable speed control.

I would venture to say that had the technology been available back in the 50's, we most likely wouldn't be writing about this right now or be looking for an upgrade.

With as much as I've spent lately- in the neighborhood of $6K, I'd rather buy a surplus motor and controller and do it myself. I have an extra motor pan and plan to use it for my R&D work. I have 3 cumulative hour meters coming in the mail. In retrospect, I believe I jumped the gun. I have the technology and experience in electronics and could easily use an LCD readout for multi-purposes- i.e. RPM, hours, fence positioning or anything else. This is not rocket science, but actually elementary school science lab project technology. I taught my little nephew how to build a computer many years ago. He has far surpassed me in his mastery of newer technology.

But for now, I'm gonna finish renovating my three headstocks. I have parts on back order- quadrants & control sheaves. I don't believe in waiting for catastrophic part failure, but rather replacing parts as they wear. But until the parts come in, I'll look at different methods of speed control- both internal & external. I need to do some basic stuff like corrosion control. The motor pans & belt covers which were not protected with any paint prior to assembly. As a result of no preventive maint, the dust accumulations attracted moisture and rust was a result.

Once I go to assembly, I want to look at ways of keeping saw dust out of the head stock. I seriously doubt any of my headstocks were used with anything more powerful than a shop vac. I know my father's headstock totally loaded the circuit & turning a shop vac on would always trip the breaker. My new workshop will be adequately wired.

[billmayo]

This looks like the solution we need for Shopsmith headstocks: http://www.teknatool.com/products/Lathe ... 20_DVR.htm

I have been playing with DC motors and controllers for a few years now. It is not as simple as it sounds or looks. My idea was to eliminate the sheaves in the headstock and use a slower speed for the bandsaw to saw metal. I was never satified with my results as new problems kept appearing until I gave up on my idea of building DC conversion kits for Mark V headstocks last year.

I made quite a few different experimental Mark V headstocks using DC motors. I replaced the control and idler sheaves with a 2" V-belt pully and used the Poly_V belt on some. Others, I used the Poly-V belt from the DC motor to the drive sleeve pully eliminating the idler shaft. I modified the speed control assy to hold the potentiometer in place of the worm control shaft, fixed the speed control dial to the speed control bracket and used the speed control handle with a large arrow added to turn the Pot. This works very well.

I never really got a easy way to adjust the belt tension as the motor mounts had to be hand built for each motor. You have to have a continuous rated DC motor and most treadmills are not for long duration operation. I have many 2 HP to 4 HP DC continuous rated motors and mostly KB 110/220 VAC input DC controllers accumlated over the years. I quickly found out that 110 VAC would only give me 90-100 VDC output and was not enough power for slow speeds. Also only a short DC motor would fit inside the headstock housing or motor pan. So I switched to higher HP DC motors but they were too long to fit inside the motor pan so I operated without a motor pan for a couple years. Not a real pretty sight but I had other problems. The DC motors comes with a flywheel/fan/Poly-V pully. I machined the Poly-V pullys to acccept a V-belt pulley for the V-belt idler pully setups. The DC motor would get extra hot even without the motor pan. So I added a fan and fan shield on the other end of the DC motors. Now the DC controller was overheating. So, I added a large aluminium heat sink on the back of the controller board. The controller still got too hot so I added a 4" cooling fan and shield on the heat sink. Now I had the low speed torque that I needed. Of course the motor mounts and adjustment bracket started bending/breaking under load and the belt would slip. I never got the motor mounts to where they would withstand the torque. About this time, I acquired a couple 10ERs.

Now I am switching my setups to the 10ER headstocks as its motor mount is excellant and adjustable. I have all the parts painted and ready to assembly for my 10ER headstock with DC motor on a Mark V frame using the 500 main and extension tables and end parts to hold and power all the Mark V SPTs.

It was a lot of fun trying to overcome each problem with a new or better solution. I will be happy to share all my misfortures and adventures with DC motors with anyone interested but I believe you are trying to ride a "dead horse" using DC motors in a Mark V headstock.

Bill Mayo

The links to the actual motor and electronics are all broken, this would be an interesting project to tackle, maybe with some help from Shopsmith we could design the next 530 a DC controlled Shopsmith with digital speed control.

With some volume we could get the upgrade to cost ~$400-$600 who would be seriously interested? I would make a link belt part of the upgrade as well. I think from what I have seen to get to 1.5 HP you need 230V AC input. I have found off the shelf controllers in dust proof enclosured for under $180 retail. The motor is still a question.

[ralphtaff]

I am not sure where dale got his information but i did post an idea to add pulleys on the outside of the Shopsmith but ONLY until i can get my money together to fix the insides of the shop smith. ALL THE SHAFTS IN THAT MACHINE NEEDS HELP. I will have to get all new parts. about $350.00 worth. I was just toying with the idea as the old 10ers had pulleys on the outside and wanted to get with the project of the ringmaster to make some bowls. I keep having things get in my way to do this so i guess i am not supposed to do use pulleys on the outside of the shop smith.First my transmission on the car broke down, then the washing machine needed a part, then i fell off the step of the front of the house ,lucky tho i did not break anything, landed on cement sidewalk. all i needed was about $50.00 extra the put the pulleys on with a different motor because of the different speed of motors. still have not done this thing as of May 2nd 2008. maybe i will wait for the $350.00 to fix this thing right. any comments welcome as to what you think of this hair brain idea. OK DISREGARD THE WHOLE THING I THOUGHT SOME ONE WAS TALKING ABOUT A SS AND USING PULLEYS TO REDUCE SPEEDS AN NOT DC MOTORS.sorry for the confusion. I missed one paragraph on dc motors on the first post. again sorry....

[paulmcohen]

I never really got a easy way to adjust the belt tension as the motor mounts had to be hand built for each motor. You have to have a continuous rated DC motor and most treadmills are not for long duration operation.
Bill Mayo

I have a Cybex commercial treadmill ($10K new), it uses a 20 amp dedicated 120 volt circuit. I think it's motor would work, it is rated for continuous use and is over 1 HP. Everything else you say may still make it impracticable.

[nuhobby]

Hi paulmcohen,

Thanks for bringing up the Home Shop Machinist articles on the Mark 5 for metalworking. I only got to read one article in the series. It was about strengthening the speed-control mechanism, mainly. Since this mag is hard to find (in stores or on-line), could you mention the main points, and why you noted a 520 with Speed Reducer can have similar capabilities?

Thanks,