Custom manual clutch

[mckutzy]

I'm guessing a cnc lathe an other machines.
As for him telling how its done or helping anyone else, I doubt it, he wants to sell these to people.
Look up a cone clutch. This is the type that he is selling.

 

[machinist@large]

Any word on the video yet? I'm not currently in the market for one, but I've been following this project with a lot of interest (as well maybe some ideas for where I could put one to use......)

 

[mckutzy]

Here's his youtube channel
http://www.youtube.com/user/mxracer1778?feature=watch

 

[machinist@large]

Here's his youtube channel
http://www.youtube.com/user/mxracer1778?feature=watch

Thanks mcklutzy; apparently I missed that link somewhere. The clutch appears to function as advertized!!!!!!
(Now I just needt to come up with the money to be able to think about a project for one.....)

 

[ChrisHartcom]

Your website http://downsbrosracing.com/ isn't up yet. Very excited to purchase a clutch or two. 3/4" shaft is perfect for my Electrathon testing. Wanting to allow coasting and still be able to use regenerative braking.

 

[ChrisHartcom]

I know I saw it back in the forum somewhere but can you reiterate the size of the clutch?

Also, is the sprocket replaceable? There was discussion early on in the forum about the sprocket not being changable but I think that was only for your prototype.

I have been looking for this for nearly two years now and am thrilled that someone, you, are actually making one. I have tried figuring out how to modify a mower's electronic PTO clutch but really wanted a manual clutch for all of the reasons you stated earlier in your forum.

Great job!

 

[mckutzy]

I was nearly at the same level of frustration of finding something like this myself, It was posted here somewhere on this site.
A company call TB woods, its a mechanical coupler, sheave drive line components manufacturer. One of there products they sell is a manual clutch for a machine of sort, almost exactly like the above, but probably 2-3 times the price.
http://www.tbwoods.com/Products_Mechanical_Clutches_Rotocam.asp

So the above(DBracing) when available will be quite the deal compared to that of various "competitors".

 

[ML-TOYS]

So far the only downside i see to this is the constant stalling factor untill you get use to disengaging the clutch. So on a kart thats a bunch of in and out of it

 

[ChrisHartcom]

McKutzy: I also found the RotoCam clutch. Quite a lot of cost and engineering for what should be a simple device. I like this one better for both price and the simplicity. RotoCam has a market and DownsBrosRacing has a market and I don't think they will mix.

ML-TOYS: I could see that as an issue, but my project is for an efficiency driven electric vehicle so I will be tying the clutch to the throttle and brake so the vehicle can coast without pushing a motor and can be engaged to allow regenerative braking. Basically the clutch needs to be engaged if either the brake or throttle is being pressed and no engaged if neither is pressed. (Brake is variable, throttle is fully engaged.) This will be quite an interesting cabling/spring/lever application because the throttle also has to activate the throttle and the brake has to also activate the brakes.

We will rig it up so we can rev the motor and pop the clutch though, so we can show it off to students at events. Races driven for efficiency aren't terribly exciting to watch.

 

[ML-TOYS]

i was referring to the overall driving using gas engines

McKutzy: I also found the RotoCam clutch. Quite a lot of cost and engineering for what should be a simple device. I like this one better for both price and the simplicity. RotoCam has a market and DownsBrosRacing has a market and I don't think they will mix.

ML-TOYS: I could see that as an issue, but my project is for an efficiency driven electric vehicle so I will be tying the clutch to the throttle and brake so the vehicle can coast without pushing a motor and can be engaged to allow regenerative braking. Basically the clutch needs to be engaged if either the brake or throttle is being pressed and no engaged if neither is pressed. (Brake is variable, throttle is fully engaged.) This will be quite an interesting cabling/spring/lever application because the throttle also has to activate the throttle and the brake has to also activate the brakes.

We will rig it up so we can rev the motor and pop the clutch though, so we can show it off to students at events. Races driven for efficiency aren't terribly exciting to watch.

 

[ChrisHartcom]

ML-TOYS: That could be a problem, but imagine how fun it will be once you get used to it!

 

[steveboy25]

It works like any other clutch but better design and iam gussing thers drums on both sizes off this clutch....!! Could be rong

 

[Kartguy6]

Let s know when you start selling! I'll for sure be one of your first buyers, this is an amazing idea such a great job on it.

 

[Kartguy6]

Pricing has been tricky since the start. The clutch requires precision machining of several critical surfaces, heat treating, gas nitriding, and finish machining. When the project was started, our goal was to hit a selling price of $100. Through several prototype iterations, we've had to make changes to maximize performance and enhance durability. Of course, this comes with added manufacturing cost. It took time, but we finally ironed out the designs to arrive at a product that works great and will be incredibly durable.

As of now, almost all of the parts and accessories have been ordered for the first set of clutches so we have a better understanding of the price. I can guarantee that the price will be somewhere between $135-150. We are thinking that we will offer the clutch at the bottom of this price range for the first 50 units, and then have to raise the price thereafter. To give you an idea about price, just for the machining and heat treating, the cheapest US shop quoted us at $450 per unit!

I'd like to get people's feedback on the above comments. I know we had said $100 before, but we believe that at a price tag of $135-150, the product is still a very good bang for your buck. Feel free to give us your feedback!

Hey I'm fine with that price, put me down for one

 

[rmm727]

Still in at that price

 

[Kartguy6]

When is the expected sell date?

 

[OasisQc]

are you a machinist ? Nice clutch !

 

[ddowns46]

are you a machinist ? Nice clutch !

Actually I am manufacturing engineer at a company that builds propulsion and power generating equipment for Navy ships. But I worked in a small machine shop during middle school and high school. I also worked as a lab technician at my universities machine shop. My dad has two mills and a lathe that I use quite a bit to build parts for my hobby cars. Other than that, my machining experience is somewhat limited compared to a true machinist.

My twin brother, who has played a big role in the design/development as well as the business side of things, is a metallurgical engineer here in the bay area. He's currently working on his masters degree in that field.

 

[ddowns46]

For all that are interested, I have attached an exploded view and parts list of the clutch. Keep in mind that the design is Patent Pending. Can anyone give an explanation on how it works?

Also, we're looking at approximately 1.5 months from now for the beta launch of 100 production clutches. We have not compiled a list recipients yet, but will send out PMs and emails as we get closer to being shipment ready. Thanks for the patience!

 

[machinist@large]

For all that are interested, I have attached an exploded view and parts list of the clutch. Keep in mind that the design is Patent Pending. Can anyone give an explanation on how it works?

Also, we're looking at approximately 1.5 months from now for the beta launch of 100 production clutches. We have not compiled a list recipients yet, but will send out PMs and emails as we get closer to being shipment ready. Thanks for the patience!

Nice!! One question though. P/N 8; it appears to use P/N 3 as the inner race, and P/N 9 as the outer race. Am I reading the diagram correctly? And I take it #3 are at least case hardened to be suitable inner and outer races? I know that it can be done; I've worked on enough different style machine tool clutches to know that it works just fine if all the metallurgy is correct.

Also, are you using a shielded type fit to protect the bearing from contamination? While in motion, it doesn't spin; when not in motion, it's going to spin all the time. And with the friction facing zone on one side, and the outer world on the other, running wide open could be a problem. A shielded class seal (like a shielded bearing) would give it durability into the "8's"; considering the market you are looking at, I don't know if you could actually get to the perfect "10".

For those of you who don't catch the scale I just referred to, a "shielded" bearing (for reference) can tolerate up to a slight to moderate amount of contamination. A "sealed" bearing is rated for moderate/ moderately severe contamination zones/applications. Anything higher, the price for the seals start to approach/exceed the cost of the bearing itself.

A shielded bearing will tolerate airborne contaminates that are not under pressure. A sealed bearing (garden/kart variety) is usually rated up to 1 Bar (approx. 15~16 PSI) of pressure applied at the seal joint to race. This is why uncontrolled compressed air is bad, and if you take a power washer to bearing; you are most likely going to get what you deserve.