Shopsmith Forums

[quote="gpmark"]One of my concerns about the crappy controller is the lack of motor protection. Sure enough the feed motor bit the dust. Opening it up I find that the windings are scorched and the permanent magnet has cracked in several places. Classic overheat and very easy with a sealed motor! And this has likely been going on for some time.

Doing a few calculations it also looks like the feed motor has marginal power. Fine if everything is going OK and you don't plane tough wood. But with marginal power its going to overheat - it should be overrated.

So I will be doing an upgrade shortly which includes retrofitting a more powerful motor (surplus Bodine from Ebay for $67 which is far better than Shopsmith and much more readily available), adding a thermal trip to the motor (a lot of DC geared motors aren't protected), and upgrading to a decent controller.

I will likely:
1) use plastic weld sticks to add on a plastic box to the existing controller,
2) put in a circuit breaker in the old box,
3) leave the motor speed in the old box (with a new pot),
4) put surge protection for the electronics in the new box,
5) and move the power connector portion of the old controller to the new plastic box.

The motor will take a mod to the drive gear and perhaps new holes in the gear cover.

If you have any input or thoughts, sure would love to hear them now.

Also, if your feed is working poorly you might want to pull the motor and check to see if the magnet is cracked or the windings are burned]

Please do divulge the details. I have a hand crank feed model and have considered adding motor/control to it. I believe your motor replacement is much better and much less $$$ than using used ss parts.

So far I have spent the following (including shipping):

Ebay Minarik controller - $40 (includes pot)
Ebay Bodine DC motor - $99
Ebay surge protector - $14
Ebay circuit breaker - $12
Thermal trip - $7

Other expenditure I would guestimate at:
Box - $20
Switch for reverse (perhaps) - $6
Edit => remove Pot -$7
Edit => add fan $5
Odds and ends - $20

So the total is somewhere around $220 dollars. I should be able to work the box, wire things up, put heat shrink here and there, put holes in the boxes, mount the board, drill new mount holes for the motor and box, and modify the gear in my shop. Worst case the gear may have to be milled at roughly $30 (larger hole with a flat and drill the gear out and put in a setscrew).

Not bad for more power, reversing, indicators for faults, minimum speed setpulse width control which is more efficient and powerful, thermal and power protection, and smoother feeding. (Edit in red.)

Another change - just got the controller and due to its height I will probably put the feed controller box separate, add a 5 pin locking connector to the old box, and put the power out on the new box.

Thoughts?

gpmark wrote:So far I have spent the following (including shipping):

Ebay Minarik controller - $40
Ebay Bodine DC motor - $99
Ebay surge protector - $14
Ebay circuit breaker - $12
Thermal trip - $7

Other expenditure I would guestimate at:
Box - $20
Switch for reverse (perhaps) - $6
Pot -$7
Odds and ends - $20

So the total is somewhere around $220 dollars. I should be able to work the box, wire things up, put heat shrink here and there, put holes in the boxes, mount the board, drill new mount holes for the motor and box, and modify the gear in my shop. Worst case the gear may have to be milled at roughly $30 (larger hole with a flat and drill the gear out and put in a setscrew).

Not bad for more power, reversing, indicators for faults, pulse width control which is more efficient and powerful, thermal and power protection, and smoother feeding.

Thoughts?

Not bad? If you can build a reliable controller for that price you should build one as a prototype and send it to Shopsmith. You might become a major supplier.