Davis and Wells 20" Bandsaw Restoration

[Jeff Carmi]

Hello everyone! Please see my first thread to bring you up to speed.

So it's taken a few months to get back around to restoring this old boy. I still don't quite have the funds I'd like, but I think I'm going to go for it. I'm going to be moving at the end of this month and figure it's a good excuse to take the saw apart. .

Here's what I'm thinking (and in the order that I'm thinking it):

- Wheels off. Send for volcanizing/balancing
- Take saw apart. Consider repainting. If so, sandblast (have never done this).
- Order all replacement parts. Definitely need new guide blocks and bearings.
- Repair hole below table (see pics above). Hopefully my metalworker buddy can do this for me.
- Possibly regrind/flatten table and repair pitting in mitre slot.
- Paint (have a spray gun, but never used it. My compressor is small but should suffice)
- Moving. Re-assemble saw at new garage.
- 3hp 3ph motor and VFD. Unsure about matching frame types and shaft diameters. Also not sure if motor RPM is a concern if I'll be using a VFD. Also considering a 5hp setup as per Dan at D&W recommends. Can't seem to find these things as cheap as people say. . .
- Driftmaster fence system, or an original if I can find one.
- Carbide blade(s)
- Make much dust!

PLEASE let me know what you guys think! This will be my first full restoration and I've got a commission to start building mid-May, so this has to happen quickly. Your thoughts and suggestions are greatly appreciated!

-Jeff

[Jeff Carmi]

I'm concerned about the CLASS B rating on a new 5 HP Baldor 3 PH. Could be a good deal, but is it worth waiting for a CLASS F? I'm definitely going with a VFD and am hoping that the overload protection will keep me safe from overheating. I realize it's also about longevity but I think 10's of 1000's of hours, when kept at proper temps, should be enough

http://en.wikipedia.org/wiki/Insulation_system

http://www.engineeringtoolbox.com/ne...ses-d_734.html

[Robert Boyd]

I would check on the price of a VFD that is rated for 5hp before you choose a motor. VFD's up to 3hp are cheap if you are running single phase input. IF you want to run a VFD for a 5hp with single phase input the price goes way up.

Start with bearings and tires and go from there. Everything else can be done at a later time.

[Rod Sheridan]

Hi, the class B insulation is an indication that it's a cool running motor, as the insulation is chosen to match the temperatures expected.

Class F is higher, however the motor will probably be a hotter running motor.

With a VFD, motor overheating is possible even if the motor doesn't run at more than rated current, if the motor is run at low speeds for a significant time period. This is because the amount of air the fan forces over/through the motor for cooling is significantly reduced.

For a bandsaw, you're probably just using the VFD as a single to three phase converter and will run the motor at rated speed, so no cooling issues.

3HP is a lot of power for a bandsaw, I would stick with the existing 3 HP motor and gain some experience as to whether it's enough.

Regards, Rod.

P.s. Last year I made a bandsaw mill with an electric motor, 3 HP was plenty for up to 20 inch deep cuts.

[Jamie Buxton]

5 hp is likely more than you need. I've got an older Laguna LT16HD with a 2 hp motor. The resaw height is 12". I use it a lot, in hardwood, and it has never bogged down. I resaw with carbide blades, which make kerfs that are .05" wide or less. You're just not removing much material with a kerf that thin, so big power isn't necessary.

[Jeff Carmi]

Thanks for the replies!

So I sealed the deal on a brand new 5 HP Baldor for $150. After several conversations with Dan at D&W I started leaning towards a more hefty motor. I know it's overkill but I'll be happy knowing my saw will never bog down.

The Teco VFD's are well priced. (http://www.factorymation.com/Products/7300CV_230V/). Considering the difference in price between a 3 HP and 10 HP VFD (which I would need to run 1 phase in/3 phase out) is fairly proportionate to their respective power ratings, I don't think the power jump is unreasonably expensive.

For the time being though, I may try to build a rotary converter and live without the VFD for a while. That way, when the time comes, I can get a 5 HP VFD and have 3 PH power available for other machines. If anyone knows good resources for building a rotary phase converter please let me know!


Will be breaking the saw down today and making a trip to see Dan at D&W. He's really helpful and has offered to give me a "lesson" on this saw. I'm having him vulcanize and balance the wheels, so he's also offered to lend me his puller.

Stay tuned for pics and updates. STOKED!

-Jeff

[Robert Boyd]

For the Factorymation VFD anything over 3hp requires three phase input. Just an Fyi. There is another company that will sell a higher hp single phase input VFD and the information is in the Moak bandsaw thread I believe.

The cool thing is you have Dan to help you out if you have any questions.

[Jeff Carmi]

So many phone calls. . .

AC Tech makes a 1/3 PH IN, 5 HP VFD for about $520 (SCF250Y). Not too bad. However. . .

After talking with Don at Lenze Americas I am convinced that the Class B rating of this 5 HP Baldor is not a good choice when run through an inverter (VFD or other). I also spoke with tech support at Baldor and they said the same thing. The Class B won't tolerate voltage spikes and variances in RPM that a Class F will when using a VFD, even if I keep it at constant speed, but especially when slowing it down.

I won't' be buying that motor now, but I may still stick with 5 HP. I guess it's back to craigslist/ebay for me. . .

[Robert Boyd]

Jeff,

If you have time visit Vintagemachinery.org for pictures in the photo index. Another option is to join Owwm.org and place in add in the Boyd section for a 5hp motor.

[Jeff Carmi]

Thanks, Robert!

Those sites have been in my bookmarks for a while now, but never used them for trade. I'll give it a shot.

[Steven Satur]

Dear Jeff: I have the same saw as you, I never thought 3hp was not enough. What are you cutting that you think you need more?
As for the org. fence, my saw came with one and I sold it last year, just wasn't what I was looking for, plus you had to remove the rail to change the blade. The Laguna might be a good choice.

Steve

[Jeff Carmi]

Hi Steve,

At this point I'm sort-of letting fate decide what motor I go with. 5HP is overkill and almost cost-prohibitive (because of the VFD), so I'll probably end up with 3HP. I'm having trouble finding 3 phase motors for cheap. I was under the impression that industrial shops let these thing go for practically free. . .

As far as the fence goes I'm still leaning towards the Laguna, despite their reputation. What fence system are you using, and how happy are you with it?

Thanks!