Clearanced Radius Trailing Arms

[Plasticman]

I think those burley ones are what i was trying to describe, makes sense to do the whole length, it looks right and avoids sudden stops in and changes in angle as the letting in method does,
i would either do that way or insterad of the discs, press some reliefs in along the length like ribs, very proffesional way to do it and even as the o/p only wanted a small bit of clearance, by using this method you can take as little as you want away.
i will agree with him ref not wanting to use spacers and altering the the slider.
mm

[Oilline]

From what i can see what Burley have done is a longer version of what i have done, but also punched some holes in the plate they welded on for whatever reason.
I have only removed the flanges and then plated over the top to tie the two halves together.
When the flanges are ground away it leaves a gap of up to 10mm between the two halves which is not easy to bridge with weld.

I cant tell if Burley have joined the two halves by letting in a strip of metal the full length and then
welded the punched plate on top

[Plasticman]

interesting, if you had a burnley one to hand a peek inside would be good, i agree, when you have a slit/hole like that you have to do something other than try weld it up as that would be a right old bodge and weak as well ,
i suppose when vw designed the arms it was easier and made sense to use mirror halves and by retaining a lip to weld together actually give it a lot of strength , especially torsionaly, a nice tubular arm would be nice, look tasty and can be made 14 ,15.16.17" any length with in reason also easy enough to make non handed as well
mm

[HarryMann]

It's possible Burley cut an accurate strip out and fill that first.

Dai lengthens them 30mm requiring 2 sets

[..lee..]

if you plan on taking a lot of metal out of the arm it would be wise to invert the seam. if you remove the seam both sides of the arm you can internally brace the arm right the way through to the seam on the other side. doka is going to get this done with me

[Dai]

Dai lengthens them 30mm requiring 2 sets

Clives right, it looks like Burley are extending them the same way, im running 31/10.5 /15 tyres and there is no need to trim the seam as there is about 20mm clearance and no need to alter the sliding door hinge


14" arm extended by 30mm by Dai Syncro 1990, on Flickr

[jes*b]

Dai , do you think you could make a set of 16" spec arms ? Hot pod did a pair recently by grafting a set of 14" onto what was left of his 16" arms, but could something similar be done with two sets of 14"'s

[HarryMann]

I think that's exactly what Dai is doing ...

but going to 30 instead of 25 mm.

[Dai]

I think that's exactly what Dai is doing ...but going to 30 instead of 25 mm.

Hes right again,
I spoke to Patrick at Coney Farm about rebuilding his 16" arms around sept/oct time, i could rebuild yours if you want,or i could make you a set like the others ive been doing using 2x 14"arms which are 30mm longer........................ but there seems to be a queue developing.

[Fabzzz]

I think that's exactly what Dai is doing ...but going to 30 instead of 25 mm.

Hes right again,
I spoke to Patrick at Coney Farm about rebuilding his 16" arms around sept/oct time, i could rebuild yours if you want,or i could make you a set like the others ive been doing using 2x 14"arms which are 30mm longer........................ but there seems to be a queue developing.

Dai, have you ever though of having the Arm scanned to have them on 3D so pressing tools can be made to do each side of the arm, then weld each side together, follow the bushed tube and the flange. I was talking with Jes at Coney and i was saying that i can't believe the money them 16" arm rich, when i think it would be cheaper to have one made from scratch by a fabricator all gigged up and everything. What do you think ?

[Oilline]

On the other side after grinding off the flange i opened up the slot to 9mm and then let in a piece of steel

Seam welded that and then ground flush


Then plated over the top

[Dai]

Oilline, that looks good and strong

Fabian.i looked at all different ways of doing it I even looked into fabing up some tubular steel ones much like trhe grasstracker lads do, but by the time you lay out for the jigging and and the labour involved and the limited market that there is for them it I didnt really seem to work out cost effective.

even VW with all there R&D finances just made up an end cap that welded onto the 14" arms instead of making a whole new pressing

[Fabzzz]

Oilline, that looks good and strong

Fabian.i looked at all different ways of doing it I even looked into fabing up some tubular steel ones much like trhe grasstracker lads do, but by the time you lay out for the jigging and and the labour involved and the limited market that there is for them it I didnt really seem to work out cost effective.

even VW with all there R&D finances just made up an end cap that welded onto the 14" arms instead of making a whole new pressing

Fair enough. I know a guy that have press and CNCs and stuff i'll ask him how much ( just for reference, and curiosity).

mate there is some Mach5 for sale on Ebay have a look. ( if you need some spares).

[HarryMann]

even VW with all there R&D finances just made up an end cap that welded onto the 14" arms instead of making a whole new pressing

...even SDP in their wisdom and financial resources didn't re-tool for 2,300 odd 16 inch (although numbers must have been guessed at when they started knocking 16s out)

You're both right I reckon...

Dai because press-tooling in those days was a totally different exercise, and a very expensive exercise, involving some development and trial and error.

Fabz because things must be very different today, for the design & lofting of the tool, much quicker and cheaper. Then making it using NC machining instead of using the traditionally highly skilled toolmaker.

So you'd need to come up with design and tooling costs and bang-out per item costs, which I'm fairly sure just would never add up even today for less than a good few hundred...

[HarryMann]

Mach 5's eh, love Dais, might like a whole good set too...