47 replies to this topic

[Thom]

So, does the orange cord unwind slowly off the motor shaft down to the stop?

[dalek]

So, does the orange cord unwind slowly off the motor shaft down to the stop?

 

Yes, but not constantly.  

 

The string pays out based on the amperage the Hudy is drawing.

 

When the amperage is below the amperage set point, the string pays out, causing the tire to be fed harder into the sanding drum, which causes the amperage to increase.

 

When the amperage then goes above the set point, the string quits paying out.

 

As rubber is removed from the tire, the amperage will drop back down below the set point and the cycle repeats until the stop screw on the Hudy makes contact.

 

The Budy will continue paying out the string for 15 seconds, but will then stop paying out the string because it can see that the amperage is not going up, which means that the stop screw has been reached.

 

The Budy will continue running the Hudy for 15 more seconds (user adjustable to run longer), then shuts the Hudy off.

 

Note:  The user sets the amperage set point using the feed rate pot.

 

Note:  The reaction time of the electronics is so fast that when controlling to set point, the amperage of the Hudy fluctuates only about one tenth of an amp.

[MrFlippant]

What methods have you employed to prevent soft rubbers from overheating and gumming up?

[dalek]

What methods have you employed to prevent soft rubbers from overheating and gumming up?

 

 

The user needs to employee the methods he uses.

 

When I feel like I'm risking overheating a tire by cutting too fast, I cut it more slowly.

 

If I was using a Budy in auto mode, I would cut more slowly by turning the Auto Feed Rate pot counterclockwise.

[MrFlippant]

The user needs to employee the methods he uses.

 

I usually use the Isopropyl Alcohol (IPA) method where you dab/drop a little IPA on the tire when the amps spike. As it evaporates, it lubricates and cools the tire. When it's gone, the tire cuts hard again and begins to heat up. I leave it cutting for just a couple seconds before dabbing on the IPA again. I do this with the pressure on and steady, until the amps during cutting (dry) are not much more than the amps while wet or without any contact. At that point, I check the results and either quit, or adjust the depth again and restart that process. This has worked well on every soft rubber I've tried, from NSR to RevoSlot and everything else.

 

If your device could do that also, or instead of increasing pressure, it would become even more hands-off than it already is. That would be even awesomer!

[dalek]

 

I usually use the Isopropyl Alcohol (IPA) method where you dab/drop a little IPA on the tire when the amps spike. As it evaporates, it lubricates and cools the tire. When it's gone, the tire cuts hard again and begins to heat up. I leave it cutting for just a couple seconds before dabbing on the IPA again. I do this with the pressure on and steady, until the amps during cutting (dry) are not much more than the amps while wet or without any contact. At that point, I check the results and either quit, or adjust the depth again and restart that process. This has worked well on every soft rubber I've tried, from NSR to RevoSlot and everything else.

 

If your device could do that also, or instead of increasing pressure, it would become even more hands-off than it already is. That would be even awesomer!

 

It appears that the purpose of your method is to speed up the cutting process.

 

 

To do what you're suggesting and be "hands-off", the Budy would need an IR temperature sensor to read the tire temperature, and a dispenser to drop alcohol on the tire.

 

For now, I just want to keep things simple because I think the Budy will work great, for most people, as-is.

 

 

Marcus, the owner of P-1 Raceway, does a lot of tire trueing/sizing for himself and some of his customers.  

 

He has used my prototype Budy.  

 

Yesterday I told him that I had just ordered parts to build a few units and he said "put me on your list".

[MrFlippant]

Good to hear.

Yes, I like for my truing to take as little time as possible, but I also only go for round/concentric, and rarely go for size reduction, which will take magnitudes longer in any case.

But no, the reason for the IPA is that it's very effective at keeping the tire from getting sticky, which can easily happen at low speed and low pressure.

Your machine would not need to measure temperature, the amp gauge you're already using would be enough, but applied differently.

 

Of course, it also depends on what kind of tires are being trued. For those unfamiliar with the technique, Ian Douglass has a couple of great videos showing how he does a set of tires.

https://www.youtube.com/@idwurks

[Mark Onofri]

One thing I've noticed is that (my) Huddy doesn't have the same rpm's as some of my cars. This results in a concave tyer at speed. Has anyone else noticed this?

[dalek]

One thing I've noticed is that (my) Huddy doesn't have the same rpm's as some of my cars. This results in a concave tyer at speed. Has anyone else noticed this?

Since the topic of this thread is about tire truer automation, possibly only having a relatively small number of followers, you might get a lot of replies if you were to post your question in a new thread.

[Mark Onofri]

OK.

[dalek]

Things are moving along but I haven't taken a video of the Budy in use because I've been spending time fine tuning the programming and the construction and the features plus learning new things relative to the project, 

 

One of those new things was learning how to design a printed circuit board.  

 

The photos below show one of the hand-wired prototype boards I made (very tedious and time consuming), and the same board but using a PCB.

 

The cost of having PCBs manufactured is very reasonable.

 

Note:  Marcus has been using the Budy prototypes for about the last month as development has progressed and there have been no issues so far.

 

 

[Phil Hackett]

I'm going to assume this project is ultimately for commercial sales. While this is an interesting project and if it is for sale to the public you need to address one thing that everyone who uses this truer will have to deal with: dust. While that might be a "they'll deal with it" policy, developing a solution, even if very few people would buy it, would show a level thoughtfulness of how the users would be using the device.

 

It might be nothing more than a simple attachment to a vacuum cleaner hose. Going beyond that might be too much.

 

Just a thought.

[Bill from NH]

I cut orange tires in my apartment once during the '70s. Then I was cleaning up orange dust for the next six months.   

 

Afterwards, I cut them inside a cardboard box for less mess.

[Phil Hackett]

I have several designs of tire truers that haven't been built and most likely never will be. All of them have a method of dealing with rubber dust. Some are overkill solutions and some are simple but marginally adequate. Dust isn't a problem until you start grinding and find out the dust goes everywhere and gets into everything. Rubber dust, or any dust really, is also not healthy to be breathing. So that's another consideration.

 

Before people start asking about these designs: these are commercial/industrial level truers. Ya know, like 110v 15 amp 1ph to 220v 3ph type powered truers. No 12v variable power supplies here. So, no, they won't be portable to take to the track.

 

Just to experiment, I set-up one of our Hardinge CNC lathes to cut tires. It works just fine, except the dust problem, but is overkill to the extreme. Years ago, I posted a video of it working on this site. Again, dust was a major problem and I didn't spend much time trying to solve it in this experiment.

 

Dust is not your friend.

[Jay Guard]

I don't remember where I got it but someone was making a 3D-printed base for a Hudy. It incorporated an opening to attach a vacuum cleaner hose to it. Some tire dust still escapes out front but it does draw the majority of the dust down into the base.

[Bucky]

There's a Hudy dust collector file on Makerworld if you have access to a 3D printer. I haven't tried it, but it looks like it'd do the job depending on the vacuum you hook it up to.

Dale, please continue to post updates of your automated truer. Seeing the evolution is interesting.

[Phil Hackett]

Just in case someone is looking for the video I mentioned in my last post: it appears I deleted it from YouTube years ago. I apologize to anyone who has searched for it.

[Racer36]

Theres a Hudy dust collector file on Makerworld if you have access to a 3d printer. I havent tried it, but it looks like itd do the job depending on the vacuum you hook it up to.

 

I’ve printed that dust collector for my Hudy. It’s a great little accessory.

[dalek]

I'm in the process of trying a new stepper motor (the one with the long black standoffs attached to it).

 

It's less than half the cost of the other stepper, the one I've been using so far.

 

The motors themselves are identical being 32 steps per revolution with internal 64:1 reduction gearing giving 2048 steps per rev at the output shaft.

 

However, an advantage of the new one, besides costing less, is that by not being a package unit, I can mount it all the way to the front of the enclosure, making more room behind the Hudy for some form of quick-change hold-down device.

 

 

[dalek]

Also, early in the project I wanted an audible alert to beep once a minute after auto mode shuts the Hudy off, like the audible alert from a microwave oven after it shuts off.

 

I had bought a couple of piezo buzzers to try but the volume wasn't very loud.

 

I was just thinking about the feature and it occurred to me that using the Hudy itself might be an acceptable way to give an audible alert.

 

Once per minute, for say 10 minutes, all of the LEDs would flash for several seconds to alert the user that the Hudy is about to run, then the Hudy would run for a couple of seconds.  

 

The user could push any switch at any time to cancel the operation.

 

Hmmmmmm... maybe.

[dalek]

Some might prefer the Hudy be separated from the enclosure (see photos below) rather than sitting on top of it.

 

It keeps the rubber debris away from the enclosure, for possibly easier cleanup.

 

It's easy to quickly dismount the Hudy by slightly loosening the two hold-down screws and then slide the Hudy sideways off the board.

 

 

 

 

 

[dalek]

The project is moving along well.  

 

Below are a few photos showing the additions of a power LED, hold-down bolts, and a Piezo buzzer.

 

The buzzer is a reminder for a situation where the user might hear the Hudy shut off, but the user is busy doing something else, and can't break away immediately.

 

The buzzer will go off for one second every 30 seconds after a tire is finished, until any switch is pressed

 

A user will be able to make the buzzer quieter, temporarily disable it or permanently disable it.

 

 

 

 

 

[dalek]

Still fine tuning software and hardware and trying new things.

 

I just received a votage/amperage display unit ($2, it even has pots to calibrate V and A, amazing).

 

The voltage display would be (if things don't become too complex) the voltage at the Hudy motor.

 

The reason I decided that knowing the voltage at the motor is somewhat important is because when I used one of the inexpensive power supplies (that can be found for less than $20) and was cutting at high amperage (Black Magic tires at or near 4.8 amps), the voltage across the Hudy motor was about 4 volts even though the power supply was set at 5 volts. 

 

Raising the power supply voltage to 6 volts got me 5 volts at the motor. 

 

The higher tire RPM obviously makes the job go faster.