PEEK Gear for the Ultra Needed

Ebiker33

Well-Known Member
I am reposting this from another thread that got no traction, but it came up in another thread again so I am posting it here as well

So far only a few Ebike companies are using this tech like LUNA and I believe Watt Wagon is working on some as well. But their focus is on making an existing product the Bafang motors better, by replacing the weaker nylon gears and the noisy metal gear with a PEEK gear paring with German bearing for a significant upgrade.
LUNA PEEK GEAR

If you deal in polymers and have not come across PEEK – it’s probably because its one of those materials which does not surface unless really needed. When it is needed – there’s little else that can be used in it’s place and this often confuses OEMs; because even among expensive, high-end engineering polymers PEEK sits at a price point that causes the client no small amount of shock.
It is important to talk about the price of PEEK before all it’s other characteristics, as this is usually the first thing the client want to discuss. Invariably, they come knowing that they need this polymer (PEEK), but knowing little else. They expect the price to be similar to Polyacetal or, at the very worst PTFE. When they find out that it is close to 10 times the price of PTFE, it comes as a huge surprise.
Why PEEK is expensive is not fully known. Perhaps it is because it has not yet reached the global scale of manufacture of more commoditized polymers, or perhaps the technology is so unique that it allows resin suppliers to charge a huge premium – knowing that alternatives are not available. As processors, we know only so much:
  • The resin is 5-8 times more expensive than PTFE
  • Processing PEEK is time consuming and expensive in comparison to PTFE
  • Machining PEEK is tricky in comparison to other polymers
Since the resin prices are not in our control, we would like to look at points 2 and 3 and discuss them in more depth. But first, let’s get a better idea of what PEEK offers.
High tensile strength
In the polymer space, it would be tough to find something tougher than PEEK. It is so strong, in fact, that machining guidelines for PEEK need to follow the same as those for metals.
This strength allows PEEK to be used in applications such as gasketing and auto components – especially where metals cannot be used, but a metal-like durability is required
High temperature resistance
PEEK melts at about 400 Degrees Celsius and is capable of running in environments of 300-325 Degrees without deforming.
While PTFE can withstand up to 250 Degrees, any pressure/ load on PTFE at this temperature will invariably cause deformation. In the case of PEEK, its hardness allows it to be in a high-load-high-temperature environment without loss of dimensional properties.
High wear resistance
Again, while both PTFE and UHMWPE can take a significant amount of wear, PEEK exhibits a high PV value and can withstand wear effects even under harsh physical and chemical conditions.
Chemical resistance
While not on the same level as PTFE for pure chemical inertness, PEEK exhibits resistance to many harsh chemicals, allowing it to be used in corrosive environments, under heavy loads
In a nutshell, PEEK’s ability to stay dimensionally stable under harsh environments makes it a highly sought after polymer. OEMs who use PEEK do so knowing well that for the properties offered, PEEK is unique and therefore expensive.
Processing PEEK
We will not delve very deep into the processing of PEEK (as this is a proprietary process unique to each processor), but we will point out the key differences between PEEK and PTFE processing (which has been looked at earlier). It should be noted that here we are referring only to compression moulding, and not injection moulding.
The main difference is that while PTFE is cold compression moulded and then loaded in batches into a sintering oven, PEEK needs to be sintered during compression itself. Furthermore, post sintering, PEEK needs to go through an annealing process, which is time consuming. This leads to a few complications:
  • Batch processing is difficult. Since the total heating cycle for a single piece can take up to 8 hours, and since heaters are expensive, PEEK is normally moulded a few pieces at a time. So unlike PTFE, where a batch of 8-10 large pieces can be moulded in series and then put in the oven for a single cycle, PEEK will offer only a few pieces in the same amount of time
  • Since PEEK is heated under pressure, issues of flash can arise as the resin becomes molten, but has pressure being applied on it. Furthermore, the pressure and temperature have to be balanced very carefully, since the temperature makes the PEEK molten, allowing it to reach its desired shape, but the pressure is responsible for vacating air bubbles from the material, so that there is no porosity.
  • Batch processing the PEEK parts for annealing is possible, but takes about 24 hours
So overall, the productivity in moulding PEEK is far below that of PTFE. This does answer, in part, the question of why the price of the finished material is so expensive.
Machining PEEK
As discussed above PEEK machines more like a metal than like a polymer. It is hard and has a significant impact on the tool. The same tool that might churn out 3000-4000 PTFE parts may struggle to churn out a few hundred PEEK parts. Again – this adds to the cost of the finished product significantly.
More importantly for machining though is that if the PEEK is not annealed properly, the part will behave erratically during machining as different areas within the material react differently to the stress being placed by the tool. Thus, cracks can develop during machining and the dimensional stability across a batch of components can vary significantly.
As a result, PEEK machining is a difficult process and there are few who are willing to take on the risks of machining such an expensive item, knowing that the rate of rejection could be very high.
In conclusion – PEEK has remained a largely niche polymer mainly due to its prohibitively high price. If it were cheaper – say around the price of PTFE – there are chances that it could steal a significant chunk of the PTFE market. PTFE still rates much higher than PEEK on characteristics like coefficient of friction and dielectric strength, but where it is a question of sheer strength, PEEK stands unmatched amongst polymers.

Here is one happy customer comments from the Luna site

Just purchased the silent gear for a bbshd motor, My bike is 2 yrs old and mainly use it for hunting and have a deer cart and haul deer with the bike. I tore the motor apart think maybe some wear of the old plastic gear but there was none, I replaced the gear with the new peek plastic gear since I believed it would still be an upgrade to the bike. While everything was apart I cleaned up everything and filled every movable gear with mobil 28 grease and put things back together. I took the bike for a test ride this morning up some hills and was super impressed on how much more quiet the motor was. Once again LUNA you hit a home run with this gear. Next I would like for you guys to produce a peek plastic gear for the ultra 620 motor to quiet that beast down.

I agree as I listen to the Ultra in video's it needs the noise reduction, it's not the loudest motor but you hear enough of it.
Also of note adding grease and swapping from NYLON to PEEK even caused a noise reduction.
I personally believe a Watt Wagon motor with X1 controller and a PEEK gear would be hands down the best motor on the market.
Only thing is I think Pushkar might have to limit the peak watts to what has been tested which is about 1600W peak the BBSHD has the the same 160nm and wattage and it's holding up.
 

Cuz Vinny

Well-Known Member
I am reposting this from another thread that got no traction, but it came up in another thread again so I am posting it here as well

So far only a few Ebike companies are using this tech like LUNA and I believe Watt Wagon is working on some as well. But their focus is on making an existing product the Bafang motors better, by replacing the weaker nylon gears and the noisy metal gear with a PEEK gear paring with German bearing for a significant upgrade.
LUNA PEEK GEAR

If you deal in polymers and have not come across PEEK – it’s probably because its one of those materials which does not surface unless really needed. When it is needed – there’s little else that can be used in it’s place and this often confuses OEMs; because even among expensive, high-end engineering polymers PEEK sits at a price point that causes the client no small amount of shock.
It is important to talk about the price of PEEK before all it’s other characteristics, as this is usually the first thing the client want to discuss. Invariably, they come knowing that they need this polymer (PEEK), but knowing little else. They expect the price to be similar to Polyacetal or, at the very worst PTFE. When they find out that it is close to 10 times the price of PTFE, it comes as a huge surprise.
Why PEEK is expensive is not fully known. Perhaps it is because it has not yet reached the global scale of manufacture of more commoditized polymers, or perhaps the technology is so unique that it allows resin suppliers to charge a huge premium – knowing that alternatives are not available. As processors, we know only so much:
  • The resin is 5-8 times more expensive than PTFE
  • Processing PEEK is time consuming and expensive in comparison to PTFE
  • Machining PEEK is tricky in comparison to other polymers
Since the resin prices are not in our control, we would like to look at points 2 and 3 and discuss them in more depth. But first, let’s get a better idea of what PEEK offers.
High tensile strength
In the polymer space, it would be tough to find something tougher than PEEK. It is so strong, in fact, that machining guidelines for PEEK need to follow the same as those for metals.
This strength allows PEEK to be used in applications such as gasketing and auto components – especially where metals cannot be used, but a metal-like durability is required
High temperature resistance
PEEK melts at about 400 Degrees Celsius and is capable of running in environments of 300-325 Degrees without deforming.
While PTFE can withstand up to 250 Degrees, any pressure/ load on PTFE at this temperature will invariably cause deformation. In the case of PEEK, its hardness allows it to be in a high-load-high-temperature environment without loss of dimensional properties.
High wear resistance
Again, while both PTFE and UHMWPE can take a significant amount of wear, PEEK exhibits a high PV value and can withstand wear effects even under harsh physical and chemical conditions.
Chemical resistance
While not on the same level as PTFE for pure chemical inertness, PEEK exhibits resistance to many harsh chemicals, allowing it to be used in corrosive environments, under heavy loads
In a nutshell, PEEK’s ability to stay dimensionally stable under harsh environments makes it a highly sought after polymer. OEMs who use PEEK do so knowing well that for the properties offered, PEEK is unique and therefore expensive.
Processing PEEK
We will not delve very deep into the processing of PEEK (as this is a proprietary process unique to each processor), but we will point out the key differences between PEEK and PTFE processing (which has been looked at earlier). It should be noted that here we are referring only to compression moulding, and not injection moulding.
The main difference is that while PTFE is cold compression moulded and then loaded in batches into a sintering oven, PEEK needs to be sintered during compression itself. Furthermore, post sintering, PEEK needs to go through an annealing process, which is time consuming. This leads to a few complications:
  • Batch processing is difficult. Since the total heating cycle for a single piece can take up to 8 hours, and since heaters are expensive, PEEK is normally moulded a few pieces at a time. So unlike PTFE, where a batch of 8-10 large pieces can be moulded in series and then put in the oven for a single cycle, PEEK will offer only a few pieces in the same amount of time
  • Since PEEK is heated under pressure, issues of flash can arise as the resin becomes molten, but has pressure being applied on it. Furthermore, the pressure and temperature have to be balanced very carefully, since the temperature makes the PEEK molten, allowing it to reach its desired shape, but the pressure is responsible for vacating air bubbles from the material, so that there is no porosity.
  • Batch processing the PEEK parts for annealing is possible, but takes about 24 hours
So overall, the productivity in moulding PEEK is far below that of PTFE. This does answer, in part, the question of why the price of the finished material is so expensive.
Machining PEEK
As discussed above PEEK machines more like a metal than like a polymer. It is hard and has a significant impact on the tool. The same tool that might churn out 3000-4000 PTFE parts may struggle to churn out a few hundred PEEK parts. Again – this adds to the cost of the finished product significantly.
More importantly for machining though is that if the PEEK is not annealed properly, the part will behave erratically during machining as different areas within the material react differently to the stress being placed by the tool. Thus, cracks can develop during machining and the dimensional stability across a batch of components can vary significantly.
As a result, PEEK machining is a difficult process and there are few who are willing to take on the risks of machining such an expensive item, knowing that the rate of rejection could be very high.
In conclusion – PEEK has remained a largely niche polymer mainly due to its prohibitively high price. If it were cheaper – say around the price of PTFE – there are chances that it could steal a significant chunk of the PTFE market. PTFE still rates much higher than PEEK on characteristics like coefficient of friction and dielectric strength, but where it is a question of sheer strength, PEEK stands unmatched amongst polymers.

Here is one happy customer comments from the Luna site

Just purchased the silent gear for a bbshd motor, My bike is 2 yrs old and mainly use it for hunting and have a deer cart and haul deer with the bike. I tore the motor apart think maybe some wear of the old plastic gear but there was none, I replaced the gear with the new peek plastic gear since I believed it would still be an upgrade to the bike. While everything was apart I cleaned up everything and filled every movable gear with mobil 28 grease and put things back together. I took the bike for a test ride this morning up some hills and was super impressed on how much more quiet the motor was. Once again LUNA you hit a home run with this gear. Next I would like for you guys to produce a peek plastic gear for the ultra 620 motor to quiet that beast down.

I agree as I listen to the Ultra in video's it needs the noise reduction, it's not the loudest motor but you hear enough of it.
Also of note adding grease and swapping from NYLON to PEEK even caused a noise reduction.
I personally believe a Watt Wagon motor with X1 controller and a PEEK gear would be hands down the best motor on the market.
Only thing is I think Pushkar might have to limit the peak watts to what has been tested which is about 1600W peak the BBSHD has the the same 160nm and wattage and it's holding up.
I have a Luna Peek gear I’ll be installing in a BBSHD this weekend.
 

Wald

New Member
I personally believe a Watt Wagon motor with X1 controller and a PEEK gear would be hands down the best motor on the market.
I would be the first to buy a PEEK gear for the Ultra!!
 

pushkar

Well-Known Member
PEEK is a WIP for us. We have struggled with it because of lack of expertise on our end to find the right manufacturer for it. We have had 2 samples made and the quality has varied wildly - leads me to believe that the "PEEK" that failed was actually just nylon in disguise.

As @Ebiker33 pointed out, we will need to limit the wattage to around 1600 / 1700W. That is a limit based on the motor construction. If we can simplify the motor, we can drive up more wattage thru PEEK.

We have this as an action item. Just a lot on our plate. If there are individuals who can help us build this out, we will be happy to fund the effort.

Here are active initiatives with our current customers are helping us with that we are funding
1. XL frame size for hydra (for 6'3-69" riders)
2. New battery pack for uber long range.
3. Smaller custom packs (14s 3p /4p).

Great question. If someone is willing to take the lead, we will absolutely try to help.
 
See if you can find any tier 3 suppliers in aerospace with PEEK experience, that's where I've seen a lot of use. And while plastic processing is not my exact area of expertise, I don't think PEEK is hard to work with, maybe just different from other plastics.

  1. Great processability* – PEEK’s ease of processing has contributed to its wide acceptance in high volume commercial applications. PEEK components are injection molding in high volume tooling equipped with hot runner systems, machined from both extruded and injection molded stock shapes and even stamped and machined from thin strip stock or film. Machining high performance thermoplastics can be a challenge because the availability of the needed shape is often limited meaning the manufacturing cost increases due to unnecessary machining swarf and the time to create it. PEEK’s high molecular weight and melt stability enables it to be extruded into large cross sections such as rods greater than 200mm, plate up to 4” and tubes with 2” thick walls. There are more than 50 different sizes of PEEK rod and plate stocked and ready for immediate shipment. Additionally PEEK is one of the few high performance thermoplastics that can tolerate the kind of extensive machining needed to produce components with complex geometries one of reasons why it is found in so many diverse applications. (*Granted this is from someone trying to sell you PEEK)
 

Ebiker33

Well-Known Member
Well the same company that makes the M600 and the BBSHD ones is in the best position to make the ultra version, I don't think LUNA wants to give that info up though.
 

brake034

Member
Region
Asia
Can someone please post pictures of the required gear? In the oil and gas industry PEEK is widely used as seat material so it's readily available as rod material.
 

brake034

Member
Region
Asia
images (13).jpeg

Is it the larger gear of this kit?
 

Ebiker33

Well-Known Member
View attachment 82911
Is it the larger gear of this kit?
Yeah that is the one, since both gears come into contact with metal you would need to do them both to really make it silient, Bafang used to use a nylon gear on the bigger one but it's metal now, I think Luna was killing them when they first came out so they went to all metal.
 

mradel

Member
Region
USA
City
Minneapolis
Anyways I know a guy who has all the tools to machine these, I have reached out to see if he could maybe make a prototype.
If he can I will need to get a real sample first, then sourcing the best raw PEEK material, but it's not cheap look at this
PEEK RAW STOCK
How many gears can a single 1 x 5 PEEK rod produce?
 

Acme

Well-Known Member
0. If my memory is correct 2.54cm is an inch. Small gear is 2.6cm. You will need the 1.5” rod $3,158 for 10‘ and the 2.5” rod $8,807 for 10’
if they are <1” wide 120 units from each rod. Material cost $26 for small and $73 for the large. \
 

Ebiker33

Well-Known Member
My guy got back to me you need a CNC machine, and he doesn't have it, not giving up I am going to try another source.
 

Ebiker33

Well-Known Member
0. If my memory is correct 2.54cm is an inch. Small gear is 2.6cm. You will need the 1.5” rod $3,158 for 10‘ and the 2.5” rod $8,807 for 10’
if they are <1” wide 120 units from each rod. Material cost $26 for small and $73 for the large. \
Yeah I am wondering if people would be willing to spend $300 plus on this to upgrade, the single bearing one Luna sells is $200. But if you are already investing 5K plus in a Ebike $300 plus isn't that much more.
 

AdilDesai

Active Member
Yeah I am wondering if people would be willing to spend $300 plus on this to upgrade, the single bearing one Luna sells is $200. But if you are already investing 5K plus in a Ebike $300 plus isn't that much more.
I likely would, but until I take delivery of my bike, I really don't know how "loud" loud is. I've heard some noise on YouTube videos, but i don't know how that translates to my ear when riding through the city.

Fascinating thread, BTW. I like when I learn things about things that aren't a part of my world.