caster sweep

[cam.in.head]

hi all. i have been reading loads and loads about alignment settings and have built myself some tools to do this. 

laser pen calibrated on adjustable base to do straight line thrust and toe measurements and a digital angle finder on an adjustable vertical bar calibrated for camber/ caster measurements.

however one thing that keeps cropping up is the caster sweep angle. in an ideal world you would just rotate your wheel 90 deg and get a caster reading from this but obviously a wheel wont have 90deg of movement so i thought move it 45 deg and just double the reading you get off the camber guage. ( ie:22.5 degree out,zero guage ,22.5 degree in and  then double the reading. that seems to make sense but i keep hearing about a 20 deg in/out ( total 40)sweep and some even say use 30 deg total and double it .?    what am i missing .it seems like basic angle measurement to me .

this weekend im going to build a quick wooden frame with 2 arms and pivot points to try and bench test the idea and see whats what.

 

[Jessopia74]

WoW that is freaky!
silver coupe is nearly back and I was think about this exact topic yesterday.

I have adjusted the top ball joints so that I can move them a little that will adjust a little.

I was reading 

And 

http://uniball.fi/cgi-bin/webio2kauppa?Cars/Opel/Opel-Ascona-/-Manta-B-RACE-eturipustus-&naytasivu=1002&id=0&saitti=rallycorsa

 

 

Edited April 1, 2020 by Jessopia74
Found the other topic I read a while back

[cam.in.head]

wow yes freaky. 

its like when you think of a song and then it comes on the radio !!!

reason behind all this is that i like to do all my own work and would rather spend all day doing something accurately with patience rather than take it to an alignment shop to be set up (in the green !)

there is no reason why we cannot set up our cars accurately ourselves.many other discussions on the web about this .some people say you can only get accuracy by thousands of pounds of equipment and others say its easily (?) obtainable at home. 

i remember years ago having a simple 2 wheel alignment done ( front tracking only) set to what they said was spot -on and it felt wrong so i took it back.they put the equipment on again and found it was a fair few mm out.they readjusted it and i left.it still felt wrong so took it back again.same again ,out again  by a few mm ?

it dawned on me that the scope of accuracy was down to how they mounted the guage on the wheel in the first place .any slight discrepancy here showed up as a lot by the time the laser had bounced from one place to another so i began thinking that there must be a better and more accurate/ consistent way to do this. even the string method would have been better and is still highly regarded. 

interesting reading and nice to hear how other people have done theirs .ive spent a fair few hours now reading up on this and enjoy it anyway so thats a bonus . 

[Jessopia74]

Yeah, I have only ever really thought the laser alignment is close, but that is pretty expensive. Whilst not outside my or my Mechanics skill set, the cost of the equipment is - so need to rely on others.

But I have been looking at Camber gauges on eBay so that’s something I can set, but the problem I could see as far as adjustment was the castor.

https://www.ebay.co.uk/itm/BG-Racing-Wheel-Camber-Alignment-Frame-Without-Digital-Dual-Axis-Angle-Gauge/362249191456?hash=item5457bc0020:g:oD4AAOSwyDFdzQro

I have seen some digital inclinometers that are magnetic, I was thinking about tac welding something liken to a frame into the stub axle just to setup, as It should be set when under normal compression of car for zero. Although I might not be able to accurately get the true reading before, I should gave a relative point to figure it’s changed angle?

 

 

 

[cam.in.head]

yes thats what i have made. a digital angle finder .its got to be more accurate than the available camber guages which are only  bubble guages.i have mounted it on a bar which is adjustable to fit rim size 13" to 16" . then calibrated on a spring loaded arm.

 

caster would then be the sweep that i am unsure about but maybee after ive had a little play this weekend it will be clearer.

thought about making something to fit inbetween the upper and lower balljoint stubs too as that would be a perfect caster measurement.adjudtment if req is limited of course with the spacers but i would imagine it will be ok anyway just want a way to measure it for my own records.

[Jessopia74]

Good thinking 👍

we are very much on the same page, not sure when I will be getting to work on mine as it still has snags to finish at body shop and with lockdown, they are not working .