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Yes that does look strange, do you know what kind of wood it was?
 

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Discussion Starter · #3 ·
no, sory i don´t know the wood, but my grandma says the wood is to dry. maybe this was from a dead tree i found?
 

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There's a row of dimples along the stress fracture too.
 

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Baumstamm, have you tested rotating forks at all? I'd like to know if you would still experience fork hits.
 

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Jörg how do you make your bearing swivels? I have designed and commissioned some blocks made of a stack of 3 ball race bearings packed within a bored-out case and retained between internal-style circlips, with the shaft also secured with external circlips. It should handle the strong side load and rotate freely. Yours looks more straightforward from your videos, but I can't tell how it's done exactly.
 

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It is very easy.

I buy ball bearings, 12 mm inner and 28 mm out dia. Those are really cheap, like 68 cents per. You need two for a grip.

http://cgi.ebay.de/10-Kugellager-Rillenkugellager-6001-2RS-12-x-28-x-8-NEU-/400038969528?cmd=ViewItem&pt=W%C3%A4lz_Kugel_Rollenlager&hash=item5d242e40b8

Then I buy 12 mm steel rods, like this one:

http://cgi.ebay.de/50-cm-Rundstahl-12mm-Rund-12-EDELSTAHL-V2A-geschliffen-/190299186170?cmd=ViewItem&pt=LH_DefaultDomain_77&hash=item2c4eb723fa

I can make three rotating handles from it, so it costs about 1.50 Euros.

Then I buy aluminum tube, inner dia 28 mm and outer dia 32 mm (2mm walls). Aluminum tubes have a perfectly smooth inside surface, as they are not welded like steel tubes.

http://cgi.ebay.de/Aluminium-Rohr-32x2mm-Alurohr-Alu-Rohre-AlMgSi0-5-/140386564776?cmd=ViewItem&pt=Rohstoffe_Materialien&hash=item20afb0faa8

I have to buy 20 cm, makes 2.40 Euros.

BOM is just over 5 Euros.

Then I cut the steel rod to about 12 cm and weld it to the frame.

Then I cut a 12 cm length from the aluminum tube.

I press in the ball bearings in the vise. Be careful not to cant the bearings. No need to heat the tube, but oil it lightly so the bearing slides in OK. The bearing will sit very tightly in the tube, not glue is necessary.

I press one of the bearings a cm in, so it does not cause a problem with the welding seam. The other one can be flush.

Next, I slip the tube with the bearings over the steel rod. This may require a few taps with the wood hammer. I usually smear a little epoxy on the rod beforehand so the bearings won't slip later.

That's it!

Good luck.

Jörg
 

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Discussion Starter · #8 ·
Baumstamm, have you tested rotating forks at all? I'd like to know if you would still experience fork hits.
no, jörg never tested a rotating fork, i would realy like to do this

my forkhits are only a problem in my mind and with some small forks, so getting my mind clear will be the best!
 

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You're going to have to get rid of all those dang women that you let hang around and play with your...slingshots! That is the only way you are going to get your mind clear.
 
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