Converted Salsa M2 open to offers

[Genevieve]

I have a quickie Salsa m2 that I converted to lithium a couple of years ago that I'm looking to sell on.

It is a 6mph chair with lift, tilt and actuating footrest with a 120 amp Rnet controller. It has a 90 Ah LiFePO4 with Bluetooth BMS and a fast charger that connects to an Anderson connector under one of the armrests. It currently has a backrest, but no cushion as it is on another chair at the minute. There is a docking pin installed for use with a Q'Straint tie down system.

I would be able to deliver within reason. I'm based in Cardiff so local(ish) delivery wouldn't be an issue. I would consider delivering further afield, but would need to discuss the best delivery options.

Let me know if anyone is interested and feel free to make an offer.

[martin007]

Have you thought about putting a price?

[Genevieve]

I was hoping to get about £3500 for it

[rover220]

I was hoping to get about £3500 for it

Probably won't get £1000 for it.

[Genevieve]

Can I ask why you think that? These chairs tend to go for over that without the work to convert to lithium

[rover220]

Can I ask why you think that? These chairs tend to go for over that without the work to convert to lithium

The average user won't part with that money for a salsa and the lithium will scare them

[martin007]

The average user won't part with that money for a salsa and the lithium will scare them

Interesting point of view...

[Burgerman]

The problem is this.

The salsa can be had very cheaply new with a low spec. Or it could. If you wanted a cheap chair then a 2 pole motor, no lights, no fancy seating options, cheap joystick, cheap upholstery, swing away footrests etc then it was very cheap. Also very rubbish! From approx 2.5K new.

Now most salsa you see on ebay are this very low spec.
My OWN salsa was a little different.
It is a great chair. But it has all the expensive options on the form ticked. That includes power centre footplate. Lift, tilt, recline, expensive arm tops, the metal large screen advanced joystick CJSM2, and 120A power module, 4 pole 6mph motors, etc.

And a bunch of mods that make it a much better chair than it was when delivered. This chair retail cost is closer to 11K than the 2.5K above. Most users do not understand the difference, they just see a salsa. Yes the frame is the same... The rest is not! So good ones go cheap. Nobody gets the difference.

Also 80Ah lithium is not adequate. For several reasons. I tested that a decade ago. When that was all that would fit. Hardly worth the effort. And too much load per cell for long service life. And BMS are problematic long term and with my programming they cant cope and cut power too. So I would junk that anyway and do as we do here and fit a proper 200Ah lithium pack and a proper balance charger. Others are scared of lithium and if anything it puts them off.

My 2017 salsa. READ the details. The details are ALL that matters here.
Then scroll and look.
https://www.wheelchairdriver.com/board/ ... 00#p122818

[Burgerman]

Heres the exact opposite to mine. R2. To me this chair is literally unusable. https://www.ebay.co.uk/itm/185439262492 ... Sw7A9iemcg
Low power PM, 2 pole motors, super skinny grey tyres, swingaway footrest meaning the seat has to be mounted so far forwards that the chair cannot steer properly and loses rear traction on uneven surfaces, and makes the thing as long as an oil tanker, etc etc. And in excellent condition is still worthless.


The details matter!
And theres maybe 20 on eBay (M2 Salsas) at half the 3.5K you are looking for. https://www.ebay.co.uk/sch/i.html?_from ... cat=177831

[steves1977uk]

Also a Lithium chair should NOT have any kind of BMS on it as those are a fire hazard. My own Lithium chair doesn't have one and is charged/balanced correctly by a PL8.

Steve

[martin007]

Also a Lithium chair should NOT have any kind of BMS on it as those are a fire hazard. My own Lithium chair doesn't have one and is charged/balanced correctly by a PL8.

Steve

What is the reason why this happens?
Does an excess of intensity heat the BMS?

[steves1977uk]

The MOSFETs can fail in a BMS causing a short which leads to a fire starting. Electric cars/buses are in the news more these days, guess why? Because they catch fire while on charge due to the BMS developing a fault causing the cells to overcharge and catch fire since they're more energy dense similar to LiPo.

Steve

[martin007]

This?

https://en.wikipedia.org/wiki/MOSFET

[steves1977uk]

Yes Martin. Also read this... https://www.exponent.energy/post/why-do ... catch-fire Headway cells can be overcharged up to 50v and take a lot of abuse, even then it doesn't explode unless you ignite the oily liquid with a naked flame.

Steve

[martin007]

Interesting information.
I have taken notes.

Thanks Steve.

[SP3_NYC]

HI, I just joined the the forum, but have followed on and off for years.

@steves1977uk
you posted:

Also read this... https://www.exponent.energy/post/why-do ... catch-fire Headway cells can be overcharged up to 50v and take a lot of abuse, even then it doesn't explode unless you ignite the oily liquid with a naked flame.

I got a 404 error on you link-- do you have a live one?

I am part of the public who is afraid of even the promising LifPo options, but know the lead-acid can't do what I want. I simply know that Idon't have enough knowledge to do lithium safely, or even seriously consider it until I deeply understand what I need to. The dangers of BMS with lithium are a key example of this; I have a healthy respect for the dangers of DIY by someone like me, or someone with more knowledge and skill who doesn't know what they don't know.

Can someone prove to us how/why a 200mAh (or other large) Lithium can be safe? I've asked experienced tecnicians and gotten mixed answers. I was told by one that they've seen too many fires from users with regular lead acid in chairs....

Perhaps I should move my post to a thread on lithium batteries?

Best Regards,
~S

[Burgerman]

Headways are yesteryear. Forget those.

When you overcharge a lead battery it produces Hydrogen, and oxygen. That can produce an explosion and thrown acid everywhere. And if you short circuit ANY battery then you can cause a fire even if that is caused by the wiring.

LiFePO4 cells are intrinsically fire safe if overcharged SEVERELY but they may release a lot of white smoke/vapour. Same if you drive a large nail thhough them... Or saw them in half. No fire. These are safer than lead based batteries. These are the ONLY ones that should be used in a powerchair.

LiPo cells as used in hobby stuff are very dangerous. They are like fireworks and can go off for any number of reasons. You dont want these!

Standard Lithium Ion (usually cobalt but there are other derivatives) are also fireworks. These are the types used in phones, laptops, those hoverboard things, and many other consumer devices. These can also cause fires. They are definitely not safe in a powerchair. You would be stting on a bomb.

As for BMS then these are the things usually responsible for fires. Either the BMS dies and its mosfets fail in shorted mode, or the thing doesent correctly balance the cells or whatever and it causes the firework type cells to burn or explode. With a LiFePO4 cell system that cant happen but the bms itself or its wiring can still burn.

So the safest option that will also make your battery last a lot longer is NO BMS and a cell balancing charger. Which is what we all do here.

I've asked experienced tecnicians and gotten mixed answers.

Well theres a surprise! Dont waste your time.

[SP3_NYC]

@Genveive sorry for cluttering your thread.
@Burgerman, yes, the LiFePO4 are what I'm investigating. Thank you for the generosity of your reply; you're doing a rare and valuble thing by hosting this forum.

@Steve1977 I wasn't so much pointing out the dead link; I was trying to say:this guy has knowledge I crave and was looking for a way to start a discusion.

It's amazing to actually communicate with other wheelchair users about all the mechanics and engineering I'm breaking my butt to learn. I'm still studying out of sheer necessity, but it's become a passion as well.

~S

[LROBBINS]

Since you are in NYC you might want to PM "expresso". Starting out not even knowing how to solder he's become a real practitioner of the LiFePO4 art. Perhaps you can even get to visit with each other.

[SP3_NYC]

@LROBBINS thanks for the tipl

[Burgerman]

Expresso is a great example. He just asked millions of questions. Sometimes 10 times over. He had no clue. But the answers he needed were right here. He can and has built more packs than I have. He is the one that does 80 mile trips around new york logged by GPS on his phone in a day. In an electrically "greedy" fast bounder.

[Burgerman]

Just found one of expressos trips!

68 miles this time. He said it nearly killed him.

I think Snaker did 78 miles, cant find that post though.

[SP3_NYC]

*sigh* I'm eating my heart out now at these trips! Someday I will again! I used to do that route on bike or roller-blade, sometimes on foot. Right now, two miles outside my house would be heaven...

I've been working on mechanical competence, learning deep background, not just chairs specifically. I need to find relilable mobility, then will focus on doing the LIfePo conversion. I'm already doing background study on basic electrical engenering -- I'd never do this project until I fully understand what I'm doing and how to be safe and do a good job. I know much of the information is here in bits and pieces (though may need updating(?), but I won't 'paint by numbers', I've got to understand a lot more before I'm willing.

I do have computer programing background (never front-end), I'll be looking to learn some microsoldering and circut anyalysis. I'm not sure if my hand is steady enough, though, for some of that. The last time I soldered/welded, I was 5 years old; my dad let me make a metal sculpture with a torch and solder -- I was good at it for Five?! Why not try at 53? My apartment's small and terrible for ventilation, but I have a plan to set up a fume vent.

I cant wait to join these people joyriding all day-- even if my body will pay a price!
I'm looking into all forms of suspension, tires and dampening polymers/elastomeres/urethanes. I eventually plan to build a chair from scratch, or possibly start from a frame.

Has anyone tried Big-rig suspension forks (mostly for rear-wheel drive chairs); theyre made by Froglegs, USA, who make these popular caster/suspension fork for manual chairs, but they used to make sturdier Bullfrog Legs to handle loaded powerchairs, supposed to absorb most of the impact of obstacles up to 3" -- like most pavers and sidewalk cracks. They will make a 'dually' caster wheel and fork to get the chair over soft ground and maybe some snow. Bullfrog legs were replaced by BigRIgs, available now. I spoke to the Frog himself, Mark Chalgren(he also runs the German Company, Rolko's new Unised States plant (it's worth checking -out many of their products), who said the old caster stems were too brittle, and sheered off, the new are better.
They are a bit pricy, but open to doing custom forks, etc.
If you've ever roller-skated or rollerbladed, skateboarded, the density and composition of those urethane/polymer wheels makes a world of difference in how much vibration you get.
https://froglegsinc.com/

I again feel that my post belongs somwhere else-- if I ever try the products, or if people are interested, I'll post the suspension fork info in it's own threds.

Thanks for the inspiration and support, guys!

Best,
~S in New York City-- Manhattan born, but currently living in Brooklyn, neara the bridge to be more precise.
@Expresso, where are you at, neighbor?

[SP3_NYC]

OH, @Snaker is another member in NYC? If so, please say hi! Or is it the name of the chair?

[LROBBINS]

No, Snaker lives in Vietnam!