Announcing new line of SubGravity DPVs engineered by Bonex!

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Light and sexy is usually a good thing! Just ask the $60B per year, health and fitness industry! 😍

---------- Post added June 24th, 2015 at 03:13 PM ----------

By the way, as I'm sitting here at my desk at work staring at my Specialized road bike leaning against the wall, I notice that the frame is made of carbon fiber. I don't think there is too much to worry about as far as durability goes. Carbon fiber is used in all sorts of demanding/high stress applications. The reason the SubGravity DPVs are made of carbon fiber is because it allows them to be extremely light weight yet very high performance. Who wants to lug around a heavy scooter? We have enough heavy dive gear to carry as it is! Light weight, competitively priced, and high performance. What's not to like? :)
 
Nose-Closure-Insta-509x509.jpg

Locking system


The Bonex locking system is located centrally in the nose. This dispenses with the need for housing snap catches. It is opened and closed quickly and reliably by releasing the central lock. Interior ventilation compensates for pressure fluctuations (SubGravity HQ is at a higher altitude after all! :wink:).
 
I'm in agreement with TBone hereCarbon Fibre Composite is Bad for this application

Disclaimer: Ex Materials Scientist for Aerospace Military Aircraft.

Bash a metal tube and it will dent, Bash CFC and it won't dent but it will probably delaminate (unless you're using an internal metal core/tube to dissipate the loads.

CFC impervious to Sea water - nope. Unless your resin is 100% then water can will get in. I suspect you're not subjecting the components to aerospace levels of inspection looking for voids (no resin) or resin rich areas (little fibre) CFC water and metal makes for a battery thus electrolytic corrosion of metallic parts.

as an analogy think for the gel coat on fibre glass when it chips off you see the fibres (yes I know that fibre glass and CFC are vastly different in construction but I wanted something easy for people to visualise)

Don't get me wrong CFC is a fabulous material I just can't believe hat the additional material, and manufacturing costs can warrant the application. If it was a complex 3D shape that would be difficult to machine or if weight saving was really critical then the balance might tip in its favour, again I agree there would be better composites.

I'll stop before I get too geeky!
 
I'm in agreement with TBone hereCarbon Fibre Composite is Bad for this application

Disclaimer: Ex Materials Scientist for Aerospace Military Aircraft.

Bash a metal tube and it will dent, Bash CFC and it won't dent but it will probably delaminate (unless you're using an internal metal core/tube to dissipate the loads.

CFC impervious to Sea water - nope. Unless your resin is 100% then water can will get in. I suspect you're not subjecting the components to aerospace levels of inspection looking for voids (no resin) or resin rich areas (little fibre) CFC water and metal makes for a battery thus electrolytic corrosion of metallic parts.

as an analogy think for the gel coat on fibre glass when it chips off you see the fibres (yes I know that fibre glass and CFC are vastly different in construction but I wanted something easy for people to visualise)

Don't get me wrong CFC is a fabulous material I just can't believe hat the additional material, and manufacturing costs can warrant the application. If it was a complex 3D shape that would be difficult to machine or if weight saving was really critical then the balance might tip in its favour, again I agree there would be better composites.

I'll stop before I get too geeky!

Although I can certainly appreciate your expertise in the aerospace industry, Bonex has been building DPVs made of carbon fiber for many years and has had excellent success with these materials for this application. The light weight materials are integral to the design of a smaller more efficient unit. Perhaps for some people, weight is not important. In that case, there are plenty of heavy, enormous scooters out there that they can choose from. The SubGravity DPV engineered by Bonex is specifically designed to take advantage of cutting edge technology in a small,highly efficient package at a cost that is VERY competitive with our competition. In fact, in most cases, when comparing apples with apples, the SG DPV is more cost effective.

We feel confident that when people compare our unit side by side with the competition, the SubGravity line of DPVs engineered by Bonex is in a league of its own.
 
his point was that carbon is not the right material to use for this application. You can still keep composite parts, just choose ones that are actually the best material for the job, and the fact is that CF is actually quite low on the list of fibers you would choose to design this if you were in the industry. Same reason people put kevlar in stuff, it's all to charge marketing premiums, it is rarely the best material.

If you wanted to use the actual best material for this application and still maintain the weight savings, you would go with a basalt/polypropylene hybrid that would keep your weight about the same, and dramatically increase your damage tolerance. Trying not to be rude, but these guys are trying to take advantage of the carbon to make more money, which is fine, but it is 100% the wrong material for this application.

Proof you might ask? Here's proof
What happens when you throw a Nova Craft Tuff Stuff canoe off a 100-foot building? | Canoe & Kayak Magazine

If you did what they did with carbon fiber, the canoe would have shattered beyond repair. They took this and went paddling with it. Sure it leaked a bit of water, but it wasn't destroyed. This weighs maybe 10% more than carbon fiber in a similar strength laminate, costs less than half of carbon, is better on the environment than carbon, and the 10% weight you gain is maybe a pound, negligible at these weights. Biased because I helped design it, but you can bet the farm that we did a full evaluation on carbon as well. Too expensive, too many compromises in durability. It's stronger than hell, but it's not tough. You don't need strong in a DPV, you need tough. When you deal with 100% cf this usually comes in many extra layers of CF to increase the toughness, which comes at unnecessary cost increases, and removes the benefit of using CF, which is to get the stiffest possible parts at the thinnest cross sections, and the lightest possible part, this is when millimeters and ounces matter. DPV's don't need that, and Bonex can provide literally 0 reason for using CF other than the marketing/sexy side of it because there are better materials out there.

Argue all you want, but carbon is not the right answer. I have no problem with them using it, it will work just fine, but if you want the actual best solution that is also conveniently cheaper, carbon is not the answer for anything except the blades, which are still plastic. You could sell the Discovery RS for $7500 with those changes, have the same dollar contribution, and have a superior scooter design. Sell the CF version for those who want to say they have a carbon scooter and save a pound or maybe two.


Good on you guys if you're selling $9k scooters, they're brilliant, wish I could afford one. It's something that will work, but is completely excessive and unnecessary for the application and doesn't bring any practical benefits to the unit.
 
Tbone,

I appreciate your thoughts on the matter, but I will iterate again that our DPVs have a long history of use worldwide and we have found them to be extremely durable, cost effective and efficient. Please keep in mind that the carbon fiber tube is a small part of the overall cost of a DPV. Even if we agreed with you that the material is not appropriate (which we don't by the way!), moving to another compound would not significantly impact the price of the scooter.

Please rest assured that we are constantly evaluating new materials and technology in conjunction with our products, but at this point, we feel we have a high performance material that meets our exacting standards.

Kind regards,
Randy

---------- Post added July 9th, 2015 at 11:10 AM ----------

Genesis 600 - 5.6 mile range - 33.5 lbs
Reference RS - 5.6 mile range - 41.88 lbs

Imagine what it would be without the carbon fiber.

Jon,

As a matter of corporate policy, SubGravity refrains from commenting on other manufacturer's threads unless our product is specifically mentioned in their thread and we find it necessary to correct misinformation about our own product. We find it in poor taste to come on a product announcement thread from another manufacturer in order to promote your own product.

SubGravity is proud of our high performance product line, our excellent customer service and our professional ethics. We will continue to build our marketshare based on these items alone. The marketplace seems to weed out the non-competitive products and companies over time.

Kind regards,
Randy
 
I never said you didn't have a material that didn't work, I said you could have a material that works better and is cheaper. That is a fact, whether or not you were aware of it prior to the design, or the engineers understood that you can very easily swap materials out in a layup with no extra R&D required is another story. DPV engineers are not composite engineers and vice versa, if they didn't work with the right people or just thought they needed CF, whoever is producing those parts for you is I'm sure quite glad to oblige due to the high cost and margin of CF. The CF tube may be a small cost, but the shroud isn't. I'm willing to bet it is at minimum $1k in cost for the pair, obviously pre markups The layup for something like that and the amount of material you need to use is quite expensive especially in that quantity.
 
...The light weight materials are integral to the design of a smaller more efficient unit.
... In fact, in most cases, when comparing apples with apples, the SG DPV is more cost effective.

We feel confident that when people compare our unit side by side with the competition, the SubGravity line of DPVs engineered by Bonex is in a league of its own.

Randy,

I apologize for stepping in on your thread, but as one of the "apples" you are comparing to, the claims regarding lightweight materials and efficiency were misleading.

Also in poor taste are "Liking" and "Thanking" of your own promotional posts by yourself and sons, who are also part of the company, under different screen names. (TOS - sock puppets)

Good luck with the product and I hope to see it at the next TBM, if there is a next one.

Jon
 

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