Tape Drive Motors?

[juki48]

I found some old tape drives and they have some nice motors in them. quite a bit larger than cr-roms but built the same. I think the stator is about 35mm. I'm almost done with my first try but I have a winding question. I wound it with 14 turns of 22g wire. think I should use a delta or a wye :?: I'm using 5x5x2's because I have them on hand and the gap actually looks pretty good. I'm not sure what kind of power these will put out but I was hoping to fly my soarstar with it, which has a geared 400 turning an 8x4. anybody used any of these motors?

[juki48]

this is it, I have re-wound it and removed the mag ring after this pic was taken.

[juki48]

here's another pic.

[LBMiller5]

What kind of tape drive are you using? Is it something like an old Colorado Jumbo, or Exabyte or something else like that?

I too have a few old tape drives lying around at work that would make good "Test Subjects"

Lucien

[juki48]

well, the one pictured I have no idea, I have a ditto 250 that is pretty much the same. the stator is the kind with a small post between each stator. dont' know if there is a technical term for those?

[DadHav]

Hello, I found some of the same. I can't remember if they were from the Iomega or the Colorado. I did find something from something that I really like. This is a 28mm 12 leg with a 16mm I.D. I would love to have at least one more to come up with a 5mm thickness. Does anyone have one of these in they're salvage box. I would be happy to pay for it. I think this stator could make an interesting motor.
DAD

[LBMiller5]

They have a big computer show every month or so down in San Diego at the Scotish Rite Auditorium. Most larger towns do since these types of shows are very popular. I have been to several of these before in Tampa, Florida, and there are always a few people selling "junk", and as you all know, one man's junk is another man's treasure. I have seen huge 4 x 4 x 3 foot pallet boxes of stuff like old 5-1/4 floppy drives, Colorado Jumbo 250 tape drives, Exabyte drives and the like. Typically these are "Grab Boxes" with a sign on them like "Everything in this box $1.00" or something to that effect. This could be a gold mine for people like us to find some great brushless stators.

If anybody finds a really good stator in something, snap a quick photo, and post it along with the dimensions of the stator. But most important, get the model number of whatever tape drive you get it from and include that as well. Then the rest of us know what to look for!

There are 2 different companies that sponsor these shows, MarketPro & MarketPro Shows. They both have a website giving all the details. There is a search engine on the site where you can look at the schedule and see if there is one in your area. MarketPro handles the New York & New Jersey area. MarketPro Shows covers the whole USA. Here is a link to the New York area site:

http://www.marketpro.com/

If you click on the "Search Schedule" button at the left side of the screen, you can search all of the cities where they have shows, and what date the next one will be held. There is another button down a couple from the "Search Schedule" called "Discount Coupons". THis will take you to a page where you can get a coupon for $1.00 off the show admission. Last time I went it was $5.00 to get in and $4.00 with the coupon.


Here is a link to the MarketPro Shows Website:

http://www.marketproshows.com/visitor/search.asp

At the bottom of this page there is a Show Search Engine to look up shows in your area. I tried it and did not get any results for San Diego. Their search engine may be down right now.

Another good source for show info is the local PennySaver type of magazine or the classified ads of your local paper.

You can also go to local computer repair stores and ask if they got any "junk" they want to get rid of. It never hurst to ask!

Well hopefully that gives some Ideas for places to look for these stators. Good luck in your search!

Lucien

[juki48]

wow, 14T might be a little too hot :twisted: I gave it a spin last night and It was runnin at about 8A and got warm to the touch. not to bad I guess. gotta set up a way to measure thrust so I can get a better idea of what's going on. temp would be nice too. it did run well though :D

[DadHav]

Hi Mr. Juki. I have a few of the same rotors, I think. Aren't they a little thin? Are you using the can that was in the drive? Any chance that you might post a picture and provide a follow up on the performance?
I know you'll just laugh at it, but I have an easy way to test thrust. There's a picture of the contraption in my galary. Oh I'm seeing infra red temperature devices in the $30 range know. The local Hobby Shop has them.
Thanks My Friend
DAD.

[juki48]

I saw your test device, I've been thinking of something similar. I do have a couple small low friction ball bearing slide rails I salvaged from work. might do something with those. it is a thin stator. didn't measure it but I would say maybe 3mm. I used the stock can and some 5x5x2 n50's I had. It actually seems to work pretty well. I thin a double stator and better can might make quite a nice motor. one nice thing about these is they come with ball bearings. any idea where to get a longer 4mm motor shaft?

[DadHav]

Thanks for the reply. The rail thing sounds like a good way to go. I've seen some that us a balance beem with the motor on one side and the other pushing against a scale, like a teeter totter (it can't be spelled that way) The thing with the that, I wondered about, is the air would be pushing against what ever surface the test stand was sitting on. Is that bad?
The 4mm shaft. I think if you check, its so close to a 5/32 that you might get away with the English equivelant. I don't know where you are located, but you might have a Mold Making Supply house in your City. Injection molds use several ejector pins and they aren't really expensive
You might get some 5/32 x 24" or so for $2or $3 each. It's been a long time since I baught any. If you can find a listing for National Tool Supply, DME Corporation, or Hasco, you might find something.
Here's a good one for you though, I have found some very exellant shaft material by buying inexpensive screw driver sets from the surplus store. I just baught a set from Harbor Freight for $1.98 and it had 6 or 8 drivers with assorted ends all 3 mm x about 6" long. They are hard and chrome plated. I had to pollish them slightly to get them in the bearing. Also I found 12 shafts from an inside measuring set that were all 4mm and very straight and hard.
Hope this gives you an idea.

DAD

[juki48]

yes, pusing against a table or any other surface is bad. I have seen setups where the device sets on the scale, then you zero it and use the prop as a pusher to push down. I would like one that is horizontal, although it is static thrust, it would still make me feel better about it. :)

[juki48]

I'm at work but here is a pic I just took with my phone. yes, I brought it to work :D a friend at work was interested in it.

[DadHav]

Oh: You Got It Bad. I take a motor with me everywhere I go too. I even keep one on the night stand, so it's the first thing I see when I get up. Sorry Sherry (my wife).
I'll trade you a nine leg for a twelve if you have any. I can't remember, do you have a lathe?
C YA
DAD

[juki48]

mmm bummer, no 12 leg. I do have a lathe :D here's another pic

[DadHav]

Are you State Side? If you need the 9 leg let me no. I'll send it up to you. PM me if you like.
C YA

[juki48]

I'm about an 8 hour drive from you. but no, I'm good for now I think. thank you though. I'll try to locate some more tape drives. If I do find a 12 pole I'll let ya know.

[DadHav]

Roger that, And thanks. Don't let the Boss catch you on the internet. You might have to pay him off with one of your motors.

[juki48]

I have a 25mm 15 pole stator that is about 25mm thick :twisted: I plan to make it as soon as I figure out how I wanna do it. I was thinking 16 magnets but it is so long I might need to add a bell to the back with another bearing. anybody tried a quad cdrom? I also don't know how to wind it.

[DadHav]

Hi again, The winding diagram that I have says 24 or 16 is a good combination. I don't know how to get a site link on the post, but you should find what you need at www.flyingcircuits.com.
OH that was easy. It went there automatically.
C YA Good Luck

[DadHav]

Sorry I had a typo and the rest is wrong too. Try www.kcflyingcircuits.com and the numbers are 14 and 16 poles for something that works. Won't that leave a big space between magnets? Will you double up the poles?
C YA

[DadHav]

This is still not working. I'm trying one more time then taking a nap.
http://www.alexrc.com/nutpol_e.htm If this doesn't work. Will someone who knows what I'm trying to do, help?
Bye
Signed:
Dummy

[juki48]

its ok, I've got the link to the site, it's my friend 8) . the motor had 4 mags, very very old hard drive. the thing is a monster. I think 16 25x4x2's or something similar will work well. have a nice nap.

[swatson144]

Thanks for the reply. The rail thing sounds like a good way to go. I've seen some that us a balance beem with the motor on one
chop
DAD
here is a sketch of my test rig. the arm is about 4' from the top of the box with a scale in it, and a window to see the scale. this keeps it out of the propwash. a heavier weight is sitting on the scale attached by a string going upto the motor mounts through a small hole in the scales box. The weight on the other arm is just slightly heavier than the weight of the motor (exact weight is not critical). Since there is no real movement the arm need not be supported by bearings but I did 3x6 mm an easy pivot would suffice. Since the offside arm is just to keep slack out of the string there is no leverage involved so the arms equal length is not a factor.
usage is
1 connect it all up and get it aligned (few seconds)
2 write down the weight shown on the scale
3 test motor and write down the weight remaing after acted on by thrust
4 subtract test weight from beginning weight = thrust
Note beginnig weight will change with motor changes and prop changes

[DadHav]

Thanks, It looks good to me. I need to give it more thought. It would also work if it were like a turntable probably.
Thanks
DAD

[juki48]

is there any reason a digital pocket scale wouldn't work on it's side? maybe with a spring providing a slight load just to give you something to zero against. This is what I was thinking about doing.

[Q]

If the digital scale doesn't have any loose parts there's no reason why it shouldn't work on it's side.

[DadHav]

Hello, If you are hunting for a scale to do this with, you can find some of them that has a hook on the underneeth side so that you can hang something rather than set it on the removable table. This might help in your application. The other thing that might be used is a dgital fish scale. Sometimes I see them for under $20.00. If needed you could substitute the hook and chain for something that hooks up easier. This would need to have some flex though because of the sensetive pressure sensor.
DAD

[swatson144]

I wasn't clear on at least 1 point, as it seems that maybe this is a stand alone rig (garage space is way too valuable). It is attached by 2 screws to the out feed table of my radial arm saw, so I can remove it and get it out of the way when I am done. It could just as easy be clamped to the edge of a work bench to get the height over the box. The ebay queen gets her scale back!

[DadHav]

I checked my digital scale and it wouldn't work sideways.
This is what I plan on using or one that I ordered, when I finish a test stand: This load cell will work in any position, even catywompass. The scale zeros itself when you turn it on. I just ordered another fish scale on E-Bay for $9.95. This one will measure ounces in increments of 100th oz. to 11 pounds. It also has a KG switch that might come in handy.
I think this will work nice because there is no measurable movement to register a reading.
WhatChaTink?
DAD

[juki48]

ok, so my tape drive motor was too hot. I rewound it with 17 turns of 24g wire. now, I get 16 oz of thrust at 9.6v 8.4A with an 8x4 prop. not too bad. :) the stock geared 380 on my soarstar only put out 13.8 oz at about 9A. that's what I wanna test this motor on as soon as the weather chills out. way to windy!!! :roll: looks like a nice motor though. didn't even get that warm :D

[juki48]

here's a new pic of 17 turns of 24g wire

[juki48]

here's my prototype air cam setup with the tape drive motor.