Var Preciray Truing Jig - Instructions Needed On How To Use It

Greengoguy

New Member
Hi, does anyone have knowledge on how to use the Var Preciray Truing Jig?
I have purchased one, but I don't have any instructions on how to operate it!
I have searched Google, to see if there may have been a manual in pdf format, but I couldn't find one.
 
Have you ever built or trued a wheel?

I've never used a wheel jig as I always just use an upturned bike with bits of sellotape and cable ties as reference points, but I always assumed the wheel jig would just be an improvement on that and it would be fairly obvious?.....
Having built a few dozen of wheelsets over a number of decades I never felt it was necessary to acquire a wheel jig.
 
OP
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Greengoguy

New Member
Hi Skol, it's always been something of a dark art to me, how to true a wheel without a jig or at least a dial!
I have trued a few wheels, but not very accurately. I haven't yet built a single wheel!
I really like this vintage Var Preciray; it has the dials for lateral and radial truing, at the same time.
I'm very keen to learn how to use it.
Have you seen one?
 

Darius_Jedburgh

Looking for the lost chord.
Have you ever built or trued a wheel?

I've never used a wheel jig as I always just use an upturned bike with bits of sellotape and cable ties as reference points, but I always assumed the wheel jig would just be an improvement on that and it would be fairly obvious?.....
Having built a few dozen of wheelsets over a number of decades I never felt it was necessary to acquire a wheel jig.
Not a very helpful comment to a new member, considering he already has the jig.
 

Big John

Guru
That's one serious piece of kit and would normally be used by a master wheel builder. I've got a Park truing stand which by comparison is a pea shooter compared to an automatic weapon. Keep hunting on the net. If it'll do the basics, ie lateral and radial truing, without using the dials then you'll be fine. There's a place called The Birmingham Bike Foundry (Google them) and it might be worth giving them a ring. Persevere because that kit is a work of art.
 

andrew_s

Guru
Location
Gloucester
Good luck with searching, but instructions are unlikely as the Preciray pre-dates the internet.

To work properly, the rollers should be positioned to match the intended position of the rim, and not taken from an un-true wheel.

The radial roller position is fairly simple as the height of the edge of the rim above the bead seat doesn't vary much, but the lateral roller needs to allow for the width of the rim as well as the hub OLN dimension. For example, if the hub OLN is 130 mm, and the outside rim width is 26 mm, the edge of the roller should be (130+26)/2 = 93 mm from the face of the wheel clamp opposite the roller, or (130-26)/2 = 52 mm from the roller-side wheel clamp face. Hopefully the scales that aren't properly visible by the name plate and at the bottom will help with this.
I'd suggest putting a known good wheel in, and seeing what the various scales seem to show.

Brief notes from someone who's used one here
 
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