Selbstbaureifen

[DougC581]

AW: Selbstbaureifen

Hallo, is anyone still reading? My reifen are improving slowly. My Deutsch perhaps not.

I did try a stahl gürtel test:
http://www.norcom2000.com/users/dci.../recumbent/tire_making/test_011/test_011.html

With the Stahl gurtel this reifen feels very hard at only 65 PSI / ~4 bar. With my weight (240lbs/108kg) on it, the sidewalls bulged out very little. I think 65 PSI may be enough air pressure.

I do not know if this is useful however. The rostfreier Stahl wire may not stay bonded in the gummi very well. Factory reifen use Stahl Draht plated with Bronze, that I could not obtain.

The gummi releases wasser so plain Stahl cannot be used, it would korrodieren..... I am attempting textile gürtel now--Polyester next. If the machine to make gürtels works.

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I did not work with the tire making during the winter. More progress should happen soon.

 

[Jack-Lee]

AW: Selbstbaureifen

Hello,

you could use stainless steel.

Or try Aramid or glasfibre.

Greetings,
Patrick

 

[DougC581]

AW: Selbstbaureifen

Hello,

you could use stainless steel.

Or try Aramid or glasfibre.

Greetings,
Patrick

The cable I have now is stainless steel.
The "real" tire companies always use bronze-plated carbon steel, but I wasn't able to find out exactly why.
Plain carbon steel wire would rust for sure, so it is bronze-plated,,,,,,, but they could use stainless-steel also, and they do not. Is carbon/bronze steel springiest? Does it stay bonded to the rubber better? Or is it just cheapest? Modern tire companies don't say, and the technical reference books that might say, are not cheap $$$$.

I don't know where to get the fiberglass in endless lengths.... Also I could only make the casing as fine as maybe 60 or 70 TPI (per ply), just because I can't find any source of nylon thread smaller than that.

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Aramid is not a good choice, because it weakens as it is flexed and predicting the strength loss over time is not reliable. The only sure way is to destructively test it. After all I have read of this problem, I even wonder if kevlar belts help protect from tire punctures. The kevlar would help a lot when the tire is new, but may not help much at all after only a few thousand km?

Also I have not been able to find straight-fiber kevlar thread, and the twisted thread is too loose--it has a lot of stretch. I could easily make kevlar beads, if I could find straight-fiber kevlar cord or thread.
The beads I use now are ~3 wraps of stainless-steel cable. So it is flexible, but not as foldable as kevlar.

With the new belt-making machine I may be able to try pre-stretching the nylon. The polyester has less stretch than nylon so I am trying that next.

 

[Klopfer]

AW: Selbstbaureifen

Hello,
Greetings,
Patrick

Wie umfangreich sind denn deine Erfahrungswerte?
Wieviele Reifen hast du denn jetzt schon selbst gebaut?
Wievile davon mit rostfreiem Stahl, wieviele mit Aramid- und wieviel mit Glasfasern?

Wäre vlt. nicht nur für mich sondern auch für DougC581 ganz interessant.

 

[leisetreter]

AW: Selbstbaureifen

Hallo, is anyone still reading? My reifen are improving slowly.

I'm following this thread, and I like it.
And for your Deutsch: we können this lesen

aramide is used for at least the carcass of military vehicle wheels

is this what you're looking for? http://www.threadstechnology.com/fibre-glass-threads.html

 

[Andreas I.]

AW: Selbstbaureifen

I don't know where to get the fiberglass in endless lengths....

And I don't know where to get hemp in endless ... fibers. And my english is ...
When building with glass or carbon, the fibers lay in the angle, wich is nessesary, and where they should be extra steif or hard, there are more layers of fibers. But this works with resin and the resion becomes hard. Gummi is weich.
But maybe with a fiber, wich is a little stronger than baumwolle or seide, maybe with hemp / hanf or leinen, and the right angle(s) and the right number of layers at the right place ...
I don't know, I buy tires and aramid/nylon-protection in a tire for ~30 euro works against puncture and the rolling resistance does'nt interest me so much, I'm not racing ... but in the size 406mm/20" there are just a few tires to buy ... and fibers with resin or fibers with gummi , that is just a little difference ...

MfG
Andreas I.

 

[DougC581]

AW: Selbstbaureifen

I am still at it. No tires yet.
I have a question.... has anyone else tried making Rinkowsky tires, since Rinkowsky himself? I know Joggl has mentioned someone trying, but anyone else before him?

I have seen that some aspects of the Rinkowsky tires -- wrapping around with metal wire -- do not work well. Does anyone else know?
I think it can work well but it will be slightly different. Not quite like car tires or motorcycle tires.

,,,,,

Mine will only use metal-wire belts, the textile is not worth the trouble I think. It takes more time to make it and the result won't be as good because of the textile belt stretching.
Casing thread angle will not be zero. It will be 15°, maybe 10°. Almost radial but not zero.

If the belt would ever break, then a tire with zero° threads would twist up on the rim -->
http://www.norcom2000.com/users/dci.../recumbent/tire_making/test_009/test_009.html
which would not be pleasant at speed I think.

 

[Patrick]

Update:

Bei mir nix Neues, außer ein paar neuen Büchern im Schrank und weiterentwickeltem Verständnis in der Sache.

@DougC581 hat aber an seinen (Draht!-)Reifen weiter gearbeitet. Seine Dokumentation mit letztem Eintrag Ende 2014 hier.

Sein letzter dokumentierter Prototyp:

 

[DougC581]

I am still at it. A couple more updates, still no reifen. I will say here when I get some made.... someday
http://www.norcom2000.com/users/dci.../recumbent/tire_making/test_014/test_014.html
http://www.norcom2000.com/users/dci.../recumbent/tire_making/test_015/test_015.html
,,,
This all has taken much more time than I thought. It will all work however.