410 replies to this topic

[stuart bowes]

meanwhile, I've been playing with a bit of cardboard and trying something out..



would you believe measured pretty much freehand (guessing a bit) and pumped that into solidworks as a sheet metal part, fitted perfectly first time, that's a bit of luck

perpective makes it look a bit off centre but it's bang in the middle

trying not to have it sticking out too far, but allowing space for wiring and a nice viewing angle trading off against the angle of the bulkhead pretty much decides the positioning for you really

I know you can get really flat cheap panel things but I want something with a decent amp built in

and then 20mins of mucking around with ms paint



it's a bit of an eighties look but with a modern screen, I might have to smooth out some of those edgy corners a bit though

I'm thinking spot welded or even pop riveted centre section from folded sheet (easy to revert to original) and two separate side sections for easier removal / access, with some sort of leather / pleather / vinyl covering to tie it all in together

Not totally sold on this yet, will play with it a bit more to see if I can find something I really like

Edited by stuart bowes, 06 April 2025 - 08:54 AM.

[stuart bowes]

back to more sensible real stuff that is actually going to happen 

 

before I start painting the inside of the engine bay I want to make sure this bonnet hinge arrangement is going to work, and work out the positioning for gas struts:

 

firstly fitted the hinges and cable tied in the washer motor to check clearance:

 

 

it's close, but does not touch

 

also the other side works obviously, no clearance issues there

 

 

and then tried to work out the effective 'weight' of the bonnet (trying to take spring force into account)

 

 

measured up hinge distance, estimated gas strut positions, lengths required.. did some maths to work out the right gas strut force and give it a go now while I can still get easy access and make holes where required

 

also with the wiper spindles in place I can get a reasonable idea of where the right stopping point is, to make sure no collision to back edge of bonnet

 

have ordered 2 x 30N struts (60N total for bonnet, where calculations show about 40n total is required minimum), 100mm travel, 270mm full length inc. end mounts (centres).  fingers crossed they're right because they're £90 the pair, ouch

Edited by stuart bowes, 17 March 2025 - 10:51 AM.

[stuart bowes]

update, I did the maths wrong.. oops.  2 x 30N is not enough to keep the bonnet up.  length and stroke still seem correct, getting them re-gassed to 2 x 60N

 

don't want to go too strong obviously as you get into the area of bending the bonnet when closing

 

also I need to make a bit of an adjustment to the geometry of the brackets

Edited by stuart bowes, 02 April 2025 - 02:54 PM.

[stuart bowes]

continuing the bonnet hinge saga now the wipers have been ordered for checking clearances, I knew it would be tight

 

I'm measuring about 15deg improvement, and about 2mm to the window wipers at closest point (guessed slightly, the screen will probably push them out a little more) so I might shave a couple mm off the dipped part of the original hinge just for a tiny bit more space maybe

 

 

showing the normal and improved positions

 

 

you might be thinking was it worth it.. yeah me too, but I've started now and every little helps I guess..  if I can get 15degrees extra reliably, I haven't measured the length of the bonnet but just as an estimate (say 800mm) I'm looking at around 200mm extra space at the front edge (slightly up and slightly back away from you)

 

I needed to add a bit of meat to the part where the gas strut goes:

 

 

 

(I'll be redoing these anyway to improve the angles and these are all a bit battered and tool-marked now)

 

the result looks a bit like this

 

 

and then I need a couple of brackets for the other end

 

 

stepped up in the middle for clearance around the indicator lights wiring hole.  these will have a captive nut for bolting from the other side.  and they'll be trimmed down to a nice shape once I know where the fixing point is

 

all 3mm steel, proper solid :)

 

the bonnet gaps aren't bad, within range of some fettling at least

 

 

 

next step make the hinges again and start marking up for fixing positions, working out the arcs for the gas struts etc, will be fun

 

struts have 100mm throw, and 60n each (120 total) holds the bonnet up perfectly well.  seems like it will be a nice smooth open and close as well, no deforming but also doesn't lift by itself which is probably the ideal 

Edited by stuart bowes, 23 April 2025 - 02:15 PM.

[stuart bowes]

found a bit of free time over the long weekend, made replacement hinges

 

old ones were a bit frankenstein by this point, cut and shut and number of times, holes welded and redrilled etc, but now I've got a working layout I can jig it

 

 

and carefully fabricate new pieces that fit exactly (and this time, are identical both sides not bodged into shape individually)

 

 

and now they are asssembled on the jig I can mark out accurate locations for the 'stopper' part to limit angles

 

you might also notice the 'dipped' part has been made slightly thinner, just a fraction to get some more clearance at the scuttle and over the wipers hopefully

 

 

 

again so both sides are identical (or close enough)

 

and the finished article reassembled. 

 

 

re-drilled the clevis pin hole to the right position so it's nice and snug on just one washer, that looseness before was causing a bit of an issue and annoying me

 

I'll probably get these zinc plated when all finished, I don't really want paint in there gunking up the pivot point and also, it'll look nice

 

quite eager now to get them fitted and work out the gas strut bracket position, etc

Edited by stuart bowes, 23 April 2025 - 02:08 PM.

[stuart bowes]

back onto these bonnet struts again trying to get the damn things finished

I sorted out the brackets for the inner wings:



extra points if you noticed I did one the wrong way around, luckily so did I just in time.. they mount to the inner wing like this



and then I assembled everything and it they all lived happily ever after.. erm, no.. so it worked really well, the struts held it perfectly and I was getting a real nice opening which I'm pretty sure would have cleared the wipers

BUT because the pivoting part was acting slightly right from the start (need stronger springs?) the back edge of the bonnet was rubbing the scuttle very slightly which obviously we can't have can we. and I didn't want to adjust the gap larger because that would look sh!t

so I was umming and ahhing and drinking tea until I realised, I can fiddle about with this later, the main thing is I have the wing brackets holes drilled, so I can paint the engine bay. so I said sod this,welded them up, and just have them 'normal' for now

 

the effort required to lift and lower is very minimal, no chance whatsoever of bonnet deformation, but it also holds itself up well. Only thing in the back of my mind is, what if there's a strong wind lol.. I'm comparing it with the volvo just in tems of effort to lift and pull back down, it's not far off really

the strut stops about 2mm short of fully 'in' at the shortest point, and 7mm off fully extended, which I hope to improve on another time (sounds minor but actually makes a decent bit of difference)

there's a good clearance from the triangle gusset as well which I was a bit concerned about hence how far the brackets stick out from the inner wings, I could have lost a couple mm off there but hey

I've got about as much as I'm happy to get by profiling the arm a little (tidied that up later so may have gained a mm or two after)



these are now the backup option if all else fails later on I have something I can bolt in and the bonnet works well.

really annoyed to be honest, it was SO nearly perfect. I guess it was a bit of a whim anyway, at least I got the gas struts working well

I'm getting 58degrees now from wing to bonnet, which I'm hoping is a little more than standard ? if anyone is bored enough to compare angles with me that would be cool

the 'kit' such as it is now looks like this



and because I want to get it zinc plated, I also dug out the remaining grotty fixings because it's priced by the tub and I might as well get them done at the same time



triple concentrate white vinegar, rinsed and refilled a couple of times until it stopped being all muddy and brown, rinse again and wire brush. I know they'll do a chemical dip anyway but why not give them the best chance of looking nice

Edited by stuart bowes, 13 May 2025 - 01:04 PM.