Mendalot
|
|
« Reply #6690 on: August 20, 2013, 09:45:58 AM » |
|
Having looked at the theory of that system (new to me) and as has been said, you shouldnt need a panhard rod. Providing that the triangulation bars have the correct geometry. But, if the top arm pivot points on the chassis are too far forward, you may get some sideways movement of the axle. Cant see a reason why a panhard rod cant be fitted though. If fitted correctly with the rod virtually in line with the axle when loaded normally, the only sideways movement will be the arc of travel, and with those shocks, that would be minimal. I stand to be corrected though guys, as it is always good to learn. This is a link to a page on my kit car build, where I have made the 5 link suspension from scratch, may be of interest to some of you ... http://www.godspeed.me/forums/viewtopic.php?f=3&t=1055&start=30
|
|
|
Logged
|
Precision Guesswork ......... What else do you need?
|
|
|
madron
|
|
« Reply #6691 on: August 20, 2013, 10:32:43 AM » |
|
theres a second hand pair of shocks on rods n sods for £50 similiar to yours
|
|
|
Logged
|
|
|
|
Manky Monkey
Administrator
Hero Member
Karma: 264
Posts: 55102
|
|
« Reply #6692 on: August 20, 2013, 01:38:32 PM » |
|
Hiya Ron. There's a queue of half a dozen people wanting to buy that pair!
|
|
|
Logged
|
On the last freedom moped out of Nowhere City.
|
|
|
kapri
|
|
« Reply #6693 on: August 20, 2013, 02:42:27 PM » |
|
The land Rover bump stops might be a bit big for your application but I believe that they can be cut down. Pretty sure that you can't fit a Panhard rod to a triangulated 4 bar system. A panhard rod actually causes the axle to move sideways but in a controlled way. Like I said before this isn't unheard of and I'd be surprised if you had enough axle arc of travel to provide the leverage required to shear through that . Would take at least 20 ton at 1/2" thick shaft.
Kev, I had a look at the break in the shaft. The break happened at the bottom of the eyelet thread (an obvious stress raiser) and shows the sort of surface I would expect from Izod testing (breaking) a fully hardened steel. No sign of repeated stress fracture, no bending and no sign of shear. I think the rod was just too brittle. Now I've seen the picture of the top mount I now can understand what's happened . On the others I've seen go have all been higher mileage motors and failed due to repeated stress raising through caused by conflict in arcs of travel with bushings that do not absorb this. Urethanes have a place in suspension but need to be used in the correct position and often with a 'compliance' rubber . I was basing my breaking strains on 8.8 quality, as you say if higher grade then going to become more brittle to shear. Are they chromed steel shafts or stainless? I've a triangulated rear on my A pickup with a mixture of urethanes ( both end lower arm) , rods ends ( chassis end of short top arms ) and heavy duty estate rubbers ( on axle end). Your correct that a panhard rod would cause a conflict of arcs by forcing the axle to one side as the suspension rises and falls. Even on a 4 bar'd or triangulated wishbone set up you can actually feel the arc of the panhard ( if you are tuned in). Usual place they break is either the bottom of eyelet thread or at the same point where they have welded eyes on some makes.
|
|
« Last Edit: August 20, 2013, 02:45:47 PM by kapri »
|
Logged
|
|
|
|
kapri
|
|
« Reply #6694 on: August 20, 2013, 02:54:42 PM » |
|
Only other damage is a small dent in the wheel arch & a squished brake line on the axle. The brakes needed re-bleeding anyway. I hear you & Chris had a few brake problems of your own the same day Kev.
Yers, Chris suffered total brake loss as we arrived at a show with crowds of people round him.Luckily as it's fitted witha twin circuit there was just enough back up to slow him down and operate when pumped. Later we came back to check and the pedal was firm again so we chanced a careful drive back. Got to Wisley services where they failed again so decided discretion was the better part of valor and had it recovered. Not as unlucky as the guy whose car caught fire on the petrol pumps who jumped in it and drove it off the forecourt with smoke pouring out from under the bonnet !! 5 fullsize fire extinguishers late it was out even before the Fire Brigade turned up. All extinguishers fired through grill and underneath as the last thing you want to do is open a hood as it can flashback instantly . 3 cop cars as well ( 2 unmarked that trawl along the A3 looking for speeders) arrived as they thought it was going to turn into a major incident with the A needing to be closed! We pulled Chris' apart and it had a split seal on front circuit. It was NOS rather than simply new so rubber had probably started to perish from sitting about.All repairs already underway.
|
|
|
Logged
|
|
|
|
Manky Monkey
Administrator
Hero Member
Karma: 264
Posts: 55102
|
|
« Reply #6695 on: August 20, 2013, 05:23:21 PM » |
|
The brakes were a nightmare to sort out on my truck weren't they, but when you see dual circuits in operation like that you realise they're worth the hassle! Knowing the quality of Chris's car, it also shows potential accidents can happen to anyone. Chrome plated rods in the shocks by the look of 'em Kev. They might be 1/2" diameter, but obviously where the thread's cut into them they're maybe 3/8". I've got rose joints on all my locating rods, right hand threads on one end & left on the other so they can be adjusted in situ. Rubber boots over the rose joints, packed with grease. The top collar, above the spring, sits quite tight to the underside of the chassis outrigger, so as well as trimming back the underside around the eyelet, I may trim back the sides a little, (being careful not to go too far obviously), to make sure nothing fouls in future. Didn't get a chance to get under it at the 'shop this afternoon, but I'll jack up the other side, remove the bottom mount & swing the shock up as far as I can to see where it fouls, then trim accordingly. Spoke to "Gaz", the shock absorber people today. They're based in Basildon, Essex, about an hour & a half away. Very friendly & helpful on the phone. Basic service, (dismantling, reassembly, change oil if necessary etc) £26.50 New rod £11.00 I told them I'd probably need new bushes too. No problem, about 40 quid altogether, plus VAT. It's my day off tomorrow & Loony won't be at the workshop, so looks like I'll be heading Essexwards. I'm booked in at a rod show in Camberley, Surrey in 11 day's time & had to change my day off to go, so I'm really hoping I can get this fixed before then.
|
|
|
Logged
|
On the last freedom moped out of Nowhere City.
|
|
|
kapri
|
|
« Reply #6696 on: August 20, 2013, 05:33:15 PM » |
|
Have you any pictures of the actual bushing in the top and bottom as well ? The top spacing may be too tight to allow any movement fore and aft meaning a longer steel centre would add more 'give'. Likewise the bottom bush how tight is the safety washer to it and does it allow and fore and aft ? If teh bottom bush is too tight then that will add even more leverage force against the top.
|
|
|
Logged
|
|
|
|
cunningplan
|
|
« Reply #6697 on: August 20, 2013, 06:14:40 PM » |
|
Tell me if I am talking total bo****ks, but I recon the shock are mounted the wrong way, you look at the picture Mankey put up and your find the bottom bolts go in from the side. My shocks were mounted like yours but then I had a Jag IRS where they pivot in the same direction as the arms, but yours are conflicting and when you have such a large ark they are bound to bind. As Kev said, fitting rose jointed ones will help, but I really think you need to mount them with the bolts going in from the sides. You could use the same brackets.
|
|
|
Logged
|
|
|
|
Manky Monkey
Administrator
Hero Member
Karma: 264
Posts: 55102
|
|
« Reply #6698 on: August 20, 2013, 06:25:32 PM » |
|
Hi Tony. ? -top & bottom bolts both go for & aft, along the line of the chassis, so top & bottom eyes are in the same direction. No photos of the bushes Kev, but I'll get new ones anyway. Old Newbie remarked on them at the workshop yesterday. The inner sleeves are virtually flush with the rubber bushes, (which are obviously wider than the eyelets), but looked a little "shaved" on the ends, so may have worn or been damaged when the shock popped.
|
|
« Last Edit: August 20, 2013, 06:27:04 PM by Manky Monkey »
|
Logged
|
On the last freedom moped out of Nowhere City.
|
|
|
phunkie hiboy
|
|
« Reply #6699 on: August 20, 2013, 07:31:25 PM » |
|
The inner sleeves are virtually flush with the rubber bushes This may well be your problem, as Kev has said already. I think before you get the standard bushes that the shock absorber company supplies, you need to look at the possibility of fitting silent bloc bushes. Think they are all a standard size. If the centres don't "stick out" far enough you could always have small spacers (0.125") turned up for either side.
|
|
|
Logged
|
Built without compromise, by the more luck than judgment method.
|
|
|
Manky Monkey
Administrator
Hero Member
Karma: 264
Posts: 55102
|
|
« Reply #6700 on: August 20, 2013, 07:40:42 PM » |
|
O.K. I'll have a look at a standard Gaz bush & sleeve tomorrow & see how a new one compares to the one in my shock.
|
|
|
Logged
|
On the last freedom moped out of Nowhere City.
|
|
|
cunningplan
|
|
« Reply #6701 on: August 20, 2013, 09:01:30 PM » |
|
Sorry Andy, this was the picture I was referring to. They should be in the same plane as the lower 4 bar bushes, look at this picture you posted I know the top mounts ain't the same, but with a couple of brackets welded to what you have already would sort that. At the moment the axle wants swing up and down and the shock wants it to go side to side.
|
|
« Last Edit: August 21, 2013, 07:12:47 AM by cunningplan »
|
Logged
|
|
|
|
Manky Monkey
Administrator
Hero Member
Karma: 264
Posts: 55102
|
|
« Reply #6702 on: August 21, 2013, 06:26:46 PM » |
|
Not sure it'd make much difference in practice Tony, but I'll look into it. I've done a complete lap of the M25 today. My day off work, so I drove around the bottom of London & through the Dartford Tunnel to Basildon in Essex. I took my damaged shock to "Gaz", the manufacturers, hoping they could repair it. "Have you come far?" "About 150 miles". "O.K then, give us an hour & we'll have it done". I wasn't expecting them to do it while I waited! So I strolled up the road to a local transport café & had an enormous fried breakfast then sat in the sunshine, having eaten way too much. Very pleasant though. Sure enough, when I went back, my shock absorber was waiting for me. New rod, new bushes top & bottom, 2 new adjusting ring grub screws, (holds it in place on the threads, although it can't really move with the spring tension on it. They were missing from both shocks), & a second hand top collar cos mine was chewed up when the rod broke. £41.40 including VAT. Sorted. I took the spring along for them to check as it'd been bent at 90 degrees. They said it was fine. "I've got no idea what poundage it is". "225 pounds" "Wow, you can tell that just by looking at it?!" ..."it's written on the bottom". http://www.gazshocks.com/
|
|
« Last Edit: August 21, 2013, 06:43:43 PM by Manky Monkey »
|
Logged
|
On the last freedom moped out of Nowhere City.
|
|
|
Manky Monkey
Administrator
Hero Member
Karma: 264
Posts: 55102
|
|
« Reply #6703 on: August 21, 2013, 06:28:19 PM » |
|
.
|
|
|
Logged
|
On the last freedom moped out of Nowhere City.
|
|
|
Manky Monkey
Administrator
Hero Member
Karma: 264
Posts: 55102
|
|
« Reply #6704 on: August 21, 2013, 06:41:11 PM » |
|
If you read the motorcycle section you might know I'm also building an XS650 Yamaha. I had ribbed aluminium mudguards made for it, by the same guy who did the ones on the Pop. I cut the rear one to length, drilled the mounting holes in it, then decided I wanted it 2 inches shorter cos I want to hang the numberplate underneath it. So having paid the nice people at Gaz & thanked them profusely, I jumped back in the car & headed straight back onto the M25. I carried on round, circling around the top of London, then down the M40 & A34 to Oxford. Darren, of Brooklands Bodycraft, has a small workshop near Witney, where he builds aluminium bodied 1920s/30s race cars. A genuinely nice & enthusiastic guy, with more talent than I'll ever manage. I showed him my 'guard with the area I needed removed marked in Typex. "No problem. Do you want a cup of tea while I fix it?" Again, I really wasn't expecting him to do it while I waited. He cut the excess off, shaped the end, warmed the aluminium with a torch, then folded the edge over short length of wire to create the beaded end. "Give us a tenner". I love small British businesses. http://brooklandsbodycraft.co.uk/index.html
|
|
|
Logged
|
On the last freedom moped out of Nowhere City.
|
|
|
|