weight of Tilite alumunum Vs titanium backrest

[ChrissyOT]

I suppose I should also note that as a 125lb person, I don't expect to stress the aluminum axle tube of my chair too much, even if I hop curbs and roll down stairs. Maybe i would if I hopped off a half-pipe or something.

I honestly didn't expect the weight difference to add up to much, but the way Tilite markets these components is a little... Hyperbolic. "imperceptibly, but measurably lighter if you have a sensitive scale edition" would be more accurate. At least with regard to the backrest.

[lazierdog]

Originally Posted by DaleB

Theory is one thing, practical application is another. Question: Why would TiLite require aluminum components when selecting their heavy duty upgrade option, as pointed out by SCI_OTR in an earlier thread?

It would appear, by this, that whatever the text book properties of Al vs Ti may or may not be, TiLite believes their Al hardware is more suitable for a heavy duty chair.

I wouldn't consider the mechanical properties of a metal "theory." Having said that, I haven't seen SCI-OTR's thread so I can't comment. I was just on Tilite's website. Are you referring to the "power adaptable frame" option? To be honest, I'm not sure what is involved in that option but I'd be surprise if the reason for not choosing titanium was strength related. The one thing you cannot argue with is the superior mechanical properties of titanium vs. aluminum. I would guess one of the factors is the cost of the material. A 4' section of 1" OD 0.049" wall of AL 6061 T6 cost about $15 vs. $76 for Ti Gr 2 (source onlinemetals.com). Keep in mind that the cost difference won't be as drastic because the titanium can have a smaller OD and/or wall thickness and still be stronger than the aluminum. Of course there maybe others factors like availability, machineability, tool life, etc. Of course the Tilite rep. could easily answer this question for us.

[grommet]

Carbon fiber axle tube .. drool. Actually I would love to use the aluminum tube, maybe it is pretty strong. I don't think Tilite would put out anything that wasn't good for the weight limit of the chair - 265lbs. I weigh about 150lbs. I do jump curbs and go down stairs but that's all. To me that's just normal getting around stuff. I don't know the properties of the CF tube except that it looks great and is probably very light. But does it crack easy etc? I'll never know.

Talking about weight, I am in the middle of installing D's Locks. It wasn't until I had my old scissor locks off that I realized (along with Steve over the phone and pics I sent him) that the standard clamps he sent won't work for me so he's sending new ones. My point is that I already have the other clamps on my axle tube and the discs that go with D's Locks and I had to put my scissor locks back on. I'm not noticing any difference in weight when I'm using the chair. For me extra weight matters when I need to get the chair in and out of a car or if I am carry a ton of weight like 20lbs of groceries which, I do fairly often.

In case anyone is wondering why I still have the clamps on that don't work, I wrecked myself on the install and didn't have anything left to remove the axle tube again and remove the clamps. I'll start work again hopefully some time this week after the new parts arrive and I'm feeling better. I'm sure about the parts getting here, doubtful about when I'm going to feel good enough to put the parts on. Eventually it will get done :-)

[t8burst]

Originally Posted by grommet

Yes, please! Thank you. Want a pair of used NaturalFit rims?

I missed this. I am in SF next week, lets hook up and I will give it to you then.

[grommet]

Originally Posted by t8burst

I missed this. I am in SF next week, lets hook up and I will give it to you then.

Definitely. Thanks. Let me know when you are back and can get together.