Hendey Refurbish #3

[682bear]

if you need to borrow a drill and reamer for the 3/4" hole let me know. I might even have some metal that would work for the bit in between too.

Hey, Matt, I appreciate it, but I found some 1/4" flat in my stock, and I'll bore the hole out with a boring bar... it won't take long to do.

Thanks for the offer, though!

-Bear

 

[tjb]

I have some 1/4" plate lying around, too, that might work if what you have isn't sufficient. Let me know. Wouldn't mind heading your way for another visit.

Regards

 

[682bear]

I have some 1/4" plate lying around, too, that might work if what you have isn't sufficient. Let me know. Wouldn't mind heading your way for another visit.

Regards

Hey, Terry, I appreciate it, but I think I have it covered.

You don't need an excuse to visit... just let me know when you want to come over... you have an open invitation.

-Bear

 

[tjb]

Hey, Terry, I appreciate it, but I think I have it covered.

You don't need an excuse to visit... just let me know when you want to come over... you have an open invitation.

-Bear

Thanks, Bear.

Ditto.

 

[682bear]

Ok, I'm stuck... not sure which way to go, and need some thoughts.

Maybe I'm overthinking this.

Hendey #3 came without a motor mount bracket, motor, and motor pulley. I have a 2 hp 230v single phase motor that I plan to use. I've been planning a simple mount bracket, fabricated from angle that allows the motor to slide vertically to tension the drive belt... loosen 4 bolts, slide the motor up, install the belt, slide the motor down to tension, then tighten the 4 bolts...

I have a copy of the blueprint for the motor pulley... it would be simple to machine from cast iron. A suitable piece of cast iron will set me back $110 the last time I checked.

The way this system works... the motor pulley is 4.5 inches diameter and 5 inches long. It is connected to the countershaft drive with a 2" wide flat belt. The driven side of the countershaft assembly has a double flat belt pulley... one pulley is free spinning (an idler), the other is geared to the countershaft. This allows, by means of a shifter rod, the belt to be slid from the geared drive pulley to the idler, thus allowing the lathe spindle to be stopped and started without turning the motor off...

Now, the problem that has me bumfuzzled...

I have not had a lot of luck getting torque transferred between cast iron pulleys and modern synthetic belts without adjusting the belts very tight... if they aren't very tight, the pulley just slips inside the belt for a few seconds until the friction overrides the inertia of the lathe spindle.

This is compounded by the fact that, in my other lathes, the flat belts are running after a gear reduction, so the slippage is minimized, but on this drive system, the flat belt will be expected to transfer the full torque of the motor at the same rate of acceleration that the motor ramps up at...

I'm seeing a very potential problem here...

Originally, this system operated using a leather belt, which has a MUCH better ability to resist slippage due to much increased friction between the belt and pulley over synthetic belts.

So, have a leather belt made, right? I could do that... but I'm seeing an issue there, also... leather stretches easily.

IOWs, If I use a leather belt, I need to come up with some method of releasing tension on the belt when the lathe is not in use. That is where I'm stuck...

I have considered replacing the pulleys with double v-belt pulleys... v-belts are capable of transferring much more starting torque than flat belts... they also are more resistant to stretching...

That would solve this issue easily, cost less money, and require less maintenance... but would also mean the 'shift to neutral under power' function would not work.

I was hoping to keep that feature... even though, IMO, it is of questionable value in a home hobby shop....

I'd like to hear some opinions, ideas, or advice...

-Bear

 

[mattthemuppet2]

Hmm, maybe a spring loaded roller to increase belt wrap on the pulley? It would be another step to shifting the belt onto the idler, but would help with both stretch and slip.

 

[682bear]

Hmm, maybe a spring loaded roller to increase belt wrap on the pulley? It would be another step to shifting the belt onto the idler, but would help with both stretch and slip.

I've considered that... I'm not sure I have enough room...

I may have to wait until I get the bracket made and see what kind of room I have to play with.

-Bear

 

[francist]

I doubt this will be a miracle cure to the problem at hand but I am reminded of when I made new drive pulleys for my Atlas MF miller a few years back. The originals are of course Zamak but I turned the new ones out of 6061 and discovered that they were much slicker than Zamak which (apparently) has a bit more of a grippy surface. Hmm, what to do. Tightening the belt tension made things uncomfortably tight so that wasn't going to work. I had some powdered rosin on the shelf -- the kind you get from art supply houses or in chunks from music stores for "rosining up" violin bows and such -- so I dusted a bit on the pulley cheeks and the v-belt surfaces and gave it a whirl.

Wow, what a difference! Instant traction on the belts and no more slip. That was five years ago or more, and I've not had to do it since. Now there is a chance that the fresh aluminum pulleys acquired a bit of wear as they rode in and gained a bit of grip surface but I also think the rosin is very long lasting. We've used it at work to tighten up the slide factor on some sliding window blinds and again it was a one-time application. There's no visible thickness to the rosin and it's not like you need a ton of it to work so it's not flying around off the belts or anything. Nor does it impart any kind of gooey feeling like a pine tar would.

As I said it may not be the total solve that you're looking for on this application but it may work for those times when you just want to tighten up the slip without mucking with the tensions.

-frank

 

[francist]

And now of course I'm reminded of our drag racing days in the 80's when we campaigned an alcohol funny car. I was a pit crew lacky in charge of putting the body stand up and guiding the driver back from burnout. And also applying the "traction compound" for the next burnout. I have no idea what was in the stuff but it was stick-eeee as all getout! It had it in this squeeze bottle about the size of a dishsoap container and I was supposed to "give a shot" under the leading edge of both tires prior to a quick spin and advance to the line. Well you know drag strips -- they're hot, fast, and furious places so by the end of the day I had that sh** everywhere! On the car, on my pants, on the steering wheel of the towback truck (oh yeah, I was driving that too) and anything else that was even close to where I was! I can't remember how we had to take it off -- lighter fuel probably -- but all I can say is stay away from that stuff!

 

[BGHansen]

And now of course I'm reminded of our drag racing days in the 80's when we campaigned an alcohol funny car. I was a pit crew lacky in charge of putting the body stand up and guiding the driver back from burnout. And also applying the "traction compound" for the next burnout. I have no idea what was in the stuff but it was stick-eeee as all getout! It had it in this squeeze bottle about the size of a dishsoap container and I was supposed to "give a shot" under the leading edge of both tires prior to a quick spin and advance to the line. Well you know drag strips -- they're hot, fast, and furious places so by the end of the day I had that sh** everywhere! On the car, on my pants, on the steering wheel of the towback truck (oh yeah, I was driving that too) and anything else that was even close to where I was! I can't remember how we had to take it off -- lighter fuel probably -- but all I can say is stay away from that stuff!

I hope you didn't have to go #1! That'd be a tough one to explain.

Bruce