Building a new Do-All band saw variable drive

[Nelson58]

What beautiful machining work. Wish I could learn to do that. Another thread to subscribe to for sure.


Nelson

 

[dozerbuilder01]

That is some incredible work. I could on dream about being able to machine something that nice. Keep up the good work.

 

[hunter1151]

Dozerbuilder........what forum are you posting the build on??

 

[SiGmA_X]

@Hunter, its linked in his sig, man... http://www.garagejournal.com/forum/showthread.php?t=132812

 

[hunter1151]

Please excuse my ignorance..................I did click on his link, I just can't figure out where he is posting. It isn't under Fabrication & Techniques is it?

 

[Trucky]

Please excuse my ignorance..................I did click on his link, I just can't figure out where he is posting. It isn't under Fabrication & Techniques is it?

Look slightly above and to the left of any threads first post to see where it's "filed" under. The one in that link is under Free Parking. This thread is in F&T.

 

[A_Pmech]

To finish up the variable drive pulley I made and installed the felt wiper retainers. These were made by turning and boring a tube from solid and parting off 1/8" wide rings. Using the pilot pressing tool and a bushing I pressed each of the retainers to depth inside the hub.

The seals were made from F7 felt with gasket punches:

Here they are being installed:

That completes the building of the variable drive sheave. I'm waiting on a special retaining clip that I broke when removing it from the axle for grinding. As soon as it arrives I'll be able to put this thing together and give it a test run on my saw.

 

[Trucky]

Machining within a few tenths? Cake walk for this guy.

Special C-clip? Breaks them every time.

 

[mjozefow]

Machining within a few tenths? Cake walk for this guy.

Special C-clip? Breaks them every time.

Ask him about leaky lawn tractor tires...

 

[chipwitch]

Beautiful work AP.

I have a 1955 16" DoAll I bought a few years ago. I've been using it in spite of it having a few issues. A few days ago, it wasn't up to the task I was using it for, so I knew I couldn't put off making some repairs. It was time to give the machine a thourough inspection.

I was pleased to see only a few minor problems, all of which I could fix easily enough. Pulled out the transmission and the bakelite varispeed pulley, which looked pretty good for its age. After buying new belts (someone used 4L's instead of 5L's) and tires, I commenced reassembly. 30 minutes from having the saw back up and running, I turned my back for a just a second... anyone here familiar with the sound of concrete and bakelite colliding? I am.

Needless to say, I now need one of the outside hubs. Wouldn't you know I'm in the middle of a job that needs to be done ASAP and I NEED my saw! I'm planning to make just the one piece out of Delrin which I'll need to order. I have a piece of aluminum here which would work. Any reason I couldn't use aluminum for the one part and keep the existing bakelite?

Also, I'm curious. You show a nylon sleeve on the ID of the fingers. I see no such thing on mine, though there is clearance for one. Is the nylon sleeve a part of the original design?

Thanks for sharing your rebuild.

 

[Nelson58]

+1, awesome build A_Pmech. Thanks for sharing your expertise.

Nelson

 

[A_Pmech]

The new axle clips arrived and I was able to assemble the axle for testing purposes yesterday. Installing the clip with spreading pliers proved exceedingly difficult. Impossible, actually. The clip is just too strong.

My solution was to whip up a tapered installation arbor. In the photo below I've already installed the clip on the axle. A second clip is resting at the top of the arbor taper. To assemble, I simply tapped the clip down the tapered arbor and onto the axle with a piece of close-fitting pipe. 30 seconds versus half an hour or more with the pliers.

Using the customer's axle and speed change arm I mounted the sheave set in my saw for testing:

This thing runs smoooooooooooth! VERY smooth. All the vibration from the stock Bakelite sheave set is gone.

I almost hate to take it off, but it's time to box it up and ship it out to the customer.

 

[A_Pmech]

See, now that's why I need to come work with you. You'll actually do the number work.. around here, it's "Oh damn it.. just drill the thing, it'll be close enough!"

Might I ask what brand of tap that is? My preference is OSG but only if the company is shelling out the dough for it.

LOL!

OSG.

I'll second that.

Thanks!

I call out 'scotch keys' (why they have two names based on nationalities I don't know) for precision acme nuts on some assemblies where they thread into the bottom of a counterbore. I usually use dowel pins though, instead of set screws like yourself.

As one might imagine trying to achieve a light interference fit for a .250 round pin goes all to hell when the guys at the shop give the 'easy' assembly to the newb who tries to drill, with a twist drill, and ream a bronze and 1018 intersection instead of interpolate it (or just plunge with an end mill) much as you found.

One of the interesting things you learn to callout on prints I guess.

First rate work, I hope you're well compensated for your talented efforts!

I was taught a "Scotch Key" is an unthreaded cylindrical or tapered key between the parting lines. A "Dutch Key" is a threaded version of a Scotch Key. Since there really isn't a standard for them that I'm aware of, I think it's always best to provide a detail view of the key or reference a shop standard so the guys on the shop floor don't go "WTF is that?"

Making a light press on a .250 undeformed pin is tricky at best. Bores between two materials of varying harness sure adds an extra dimension of fun!

Thank you!

Awesome work there!

Thanks!

What beautiful machining work. Wish I could learn to do that. Another thread to subscribe to for sure.


Nelson

Thank you, Nelson.

That is some incredible work. I could on dream about being able to machine something that nice. Keep up the good work.

I could say the same about the work you're doing on the dozer!

Ask him about leaky lawn tractor tires...

Ya. Half a tube of silicone caulk fixes bead leaks forever.

Machining within a few tenths? Cake walk for this guy.

Special C-clip? Breaks them every time.

That's not the only thing I'm good at breaking.

Beautiful work AP.

I have a 1955 16" DoAll I bought a few years ago. I've been using it in spite of it having a few issues. A few days ago, it wasn't up to the task I was using it for, so I knew I couldn't put off making some repairs. It was time to give the machine a thourough inspection.

I was pleased to see only a few minor problems, all of which I could fix easily enough. Pulled out the transmission and the bakelite varispeed pulley, which looked pretty good for its age. After buying new belts (someone used 4L's instead of 5L's) and tires, I commenced reassembly. 30 minutes from having the saw back up and running, I turned my back for a just a second... anyone here familiar with the sound of concrete and bakelite colliding? I am.

Needless to say, I now need one of the outside hubs. Wouldn't you know I'm in the middle of a job that needs to be done ASAP and I NEED my saw! I'm planning to make just the one piece out of Delrin which I'll need to order. I have a piece of aluminum here which would work. Any reason I couldn't use aluminum for the one part and keep the existing bakelite?

Also, I'm curious. You show a nylon sleeve on the ID of the fingers. I see no such thing on mine, though there is clearance for one. Is the nylon sleeve a part of the original design?

Thanks for sharing your rebuild.

I know the sound of Bakelite on concrete too! My Bakelite sheave set hit the concrete last night. I thought it shattered, but it was only belt dust flying everywhere. Luckily, I only have one big crack. It will run long enough for me to get the new sheave made up.

If you're going to setup to make part of the sheave, you might as well make all of it if you have the time and materials. Most of the machining time is in the radial slots. If you have a good hub, that will save some time too. If you press your aluminum parts, just be sure to account for the bore collapse.

The MDS Nylon bushing replaced the original lubricated bronze bushing. Nylon runs dry so it doesn't attract dirt like an oiled bronze bushing would, which should reduce wear and gumming up. Using a Nylon bushing also relieved the need to use a slotted bronze bushing to contain a wiper felt.

 

[chipwitch]

LOL!

I know the sound of Bakelite on concrete too! My Bakelite sheave set hit the concrete last night. I thought it shattered, but it was only belt dust flying everywhere. Luckily, I only have one big crack. It will run long enough for me to get the new sheave made up.

Wow. Thanks for owning up to it. I feel a little better now.

If you're going to setup to make part of the sheave, you might as well make all of it if you have the time and materials. Most of the machining time is in the radial slots. If you have a good hub, that will save some time too. If you press your aluminum parts, just be sure to account for the bore collapse.

The hub is good. The rest will have to wait a while. Too busy. But, I'm doing the slots with a CNC VMC. Setup is a breeze since I'll just 3D contour it. You can bet I'll be saving the program though!

The MDS Nylon bushing replaced the original lubricated bronze bushing. Nylon runs dry so it doesn't attract dirt like an oiled bronze bushing would, which should reduce wear and gumming up. Using a Nylon bushing also relieved the need to use a slotted bronze bushing to contain a wiper felt.

I see it now. I thought the picture you posted with the nylon insert was the fixed end side of the pulley... not the center piece. For a minute there, I thought I was missing something.

Aluminum arrives tomorrow. Wish me luck.

 

[chipwitch]

One more thing, A_P... what angle did you measure? The face of my Bakelite was worn uneven. I consulted Machinery's Handbook and modeled mine for 16". After reading MH, I was wondering if the face may have been designed slightly convex to compensate for the variable pulley diameters? That would explain some but not all of the variation I see on mine.

 

[taumac]

Im simply amazed.... I can only dream of having those machines and the knowledge and math skill require to use them.

 

[cnc-me]

Fantastic job AP!
How long did it take you?
Much to ambitious for me, probably would have went to a bigger motor and an
AC drive.

 

[ww_big_al]

Gee, I know this is an old thread but what happed to all the pictures?

 

[Stuart in MN]

Gee, I know this is an old thread but what happed to all the pictures?

I can see all the pictures. It may have something to do with your web browser.

 

[ww_big_al]

I can see all the pictures. It may have something to do with your web browser.

Got it fixed. Web browser was acting up.

 

[convx4]

For me

This post is internet Brail.

No Photo Bucket pictures.

A good read but not ****.

My web browser is up to date.

 

[tarbellb]

Nothing to do with browser, Photobucket started charging for picture access/use. This is now all over the internet.