I am going to get the courage to face it again. I have been drawn to a conclusion with intent of lifting the hinge arms out of the rest position slightly, so the forward movement commences immediately. Right now, there is a kind of dead spot it seems just for a couple of millimetres of initial movement where the hinge seems to be in limbo so to speak as it commences its path of movement and rides too low to clear the firewall lip edge. I had to walk away and I am a pretty patient individual, but I needed to avoid being drawn in by the problem and grasping at straws which could have lead me to do some dumb stuff. So I am now in a cooling off period just mulling over my next steps and listening to others view points. I am just so close, but finding the tweak that will get me over the line is killing me right now... Thanks for your continued interest.
I know exactly what you are talking about. It was hard to get lift before the tilt if that makes sense. I had a different style hinge so I'm not sure it applies to yours. I used cardboard and Brads on a much smaller scale to get the hinge points. Trial and error, scrap paper, and luck.
Thanks Dyce, yes I have done similar trial prototypes leading up to the final product. A friend from another Forum had raised a point that seemed obvious after I had read it and was something that was doing my head in with hinge lift. He was saying he had a production vehicle with a torsion bar spring lift in the trunk (similar to a hood I suggest). His torsion bar broke after many years of use and from that point on his trunk lid would bind and scrap when operated. He is suggesting some kind of pre-load may be required as a kind of prompt if you like to the hinge to get it to initiate the lift first. Since I have no spring loaded type holding method and was just going to use a prop, maybe this is what is missing in my case!!!
That makes sense. Mine had an arc it traveled in until the hinge went over a center, then the arc reversed. I made it swing closed just over center. I can see how having a spring load over center could change the geometry enough to straighten the arc. I was just thinking about the hood and hinge designs used by ford and chevy and the hoods opening from the front only fit the cowl through the 50s. The front of the hood makes the nose of the car so it can move forward. The 60s hoods fit flush but are very flat and only have to lift a little bit. I think the forward tilt hinge I used worked (sort of) because I could make the hinge arms long resulting in a wider arc.
Hinges can really do your head in once you really get into them. I will persist for now, but do have a plan B, which is to use another hinge design (drawings) which I purchased from a guy in Canada for little money. Only problem IMHO is that it does not look pretty as it has super lift and sticks up oddly when open. Looks kinder fragile, like a scissor lift effect... Plan C is to scrap the hinge and just tie down the hood and make it hand removeable which really goes against the grain in my book... I am not all that competitive, but I hate being beaten when I am so close to the finish line.
Well men, I think I am all tweaked out. My latest hinge pocket tweaking has gone some way to improving the lift motion. It is more obvious now that the peak of the hood arc at the cowl end is the issue. As the hood rotates up the arc is moving from the horizonal more into the vertical plane and hence needs space towards the windshield end. It is so damn close now that if I put a nylon washer in its travel path is rides on the washer and then clears. The washer is protecting paint scratching for now. A guy from another Forum had earlier suggested a small nylon wheel or skid wedge for that edge of the hood. It did not make much sense to me then, but now it does. I need more thinking time as this is turning into brain surgery... I really don't have anything in the actual hinge or hood left to tweak now. I think if the straight seal lip in the cowl/firewall sheet metal had a curve or bow in it at about the center line of the hood instead of being straight, it probably would saved my bacon and cleared. Pre-load is definitely a part solution that I at this late stage will not be able to take advantage of. It sure is something to consider for others following in my foot steps.
Two things...Closed Gap from Hood Edge to Cowl...increasing gap to near max with visual consideration and considering paint thickness. This decreases the amount of hood edge tilting down and colliding with the paint when opening and consider aviation quality rub strip or rubber buttons and adhere...perhaps with adhesive only...so the hood is colliding with the buttons or rub strip, rather than paint... Adding springs to hinge to help activate action to the hinge mechanism that could be needing more weight related load to activate desired action... This truly is a mechanical challenge even in the relative simplicity of this movable joint...I am thinking of that saying Walking a Mile in the Shoes of Another and that is more than meets the eye but achievable... Another thing is the hood is tacked and not fully contoured with its outer layer fixed which may affect the proper lift and tilt movement. Since you touched upon some of these thoughts before I sent this I still thought this may help get beyond the Challenge at hand... One more thought...a metal cam/deflector think idle set screw set clamped or bolted in the hinge that delays or alters the tilt actuation till the hood is clear... I'm a mechanical thinker but an artist not an engineer... I roll with your journey in Hoodlumdom...
Boy, you are up pretty late young man or should I say boy you are a early riser. Thanks for your thoughts and I hope to have some more offerings in the next 24 hours. I appreciate motivational comments during these testing times. I have almost cut a track in my yard from the shop to the house by just walking away from these recent headaches...
I'd remove a few things and go for a motivational/spiritual ride come back and go for additional adjustments... Here's another thought you may have already considered is tapershimming hinge to firewall to preload/effect hinge to change how hood deflects once front pin is released....you may even need angle shim at hinge to hood mount...there is a quick setting mold maker in a tube you can apply to get proper shape of the mount area...they use it in machining... I had the last ride of the season I believe the other day..near or at freeze has set in salt soon...I think you have winter setting in too but maybe one more chance this season... I have been giving some thought to a hood that is quick release myself as it's a showing bling beating out streamline Race on the street Hotrod but lacking a hood can limit a Journey...
I've gone back to the drawing board to figure out if there is anything I can improve on my current hinge design that will get me over the finish line. I have determined the front lifting arm is running too quick a head of the rear lift arm causing the incorrect sequence of movement since I don't have any preload on my hinge. I have played with several scenarios relating to changing front arm pivot point lengths, but this affects my opening angle and I seem to be losing opening height. So, I have ventured to review the rear arm movement which in hindsight was the obvious place to review, but like a dumb ass I left it to last. Getting the rear arm to respond quicker and with a little more lift height seems to mean that I need to reposition the fish plate and change its rest angle. So, I have spent some time pulling out old discarded hinge parts and mocked up a copy of my current hinges and then played with repositioning pivot points and checking lift movement. I could be onto something, but I need to do more comparisons first to be totally satisfied. I think my CAD guy may have rushed the last drawings and did not get too involved in the initial lift detail.
Did this for my ‘33 https://www.jalopyjournal.com/forum/threads/easy-hood-for-my-33-pickup-made-from-46-hood.623660/
Thanks for sharing and providing some extra motivation. I like your project hood, it shows great innovation and thought. You can see from your donner hood what I was saying previously about cutting back the center high point of the hood at the rear to help eliminate bind in my case.
I note that many other vehicles of the 1940's and 50's with high arched hoods had a similar kind of V shape or taper to the center along the back edge of their hoods, probably as a means of avoiding exactly what I am experiencing now. I've have decided to take a day or two off and do some gardening instead and mix with non car friends as a means of clearing my head for now...
Well folks, its been a while. Between life, a spell of weather and a lack of motivation, I have now got a new idea and have started implementing it. Well, 2 ideas actually; 1st is a slightly modified hinge design, nothing drastic, but it appears that it may offer some extra lift at the rear. 2nd I have decided to do a mock up on my old wooden engine bay buck and use it to make any hinge position tweaks. Attached are a couple of pic's of the hinges in place as per the real engine bay, with the exception, I have moved the hinges in from the outer edge by 1" and raised them 3/8". I can not give a detail explanation for this move, other than to say I am going with my gut right now. Fingers crossed again...
Sorry for no updates, but I've been off the radar with a really bad bout of Bronchitis. It has taken some time to get over, although I am still not fully recovered yet, hence nothing much has happened.
The wooden buck looks like a great idea. Now you can see what is happening under there. Sent from my SM-T350 using The H.A.M.B. mobile app
Well, after numerous attempts to get a hinge location relating to the firewall and have a clear lift, it seems I have not been successful. In the meantime, I have come down with a case of Chronic Fatigue Syndrome CFS which has been no fun and taken away most of my project motivation. However, I can now see the light at the end of the tunnel with this CFS. It has been a challenge to say the least, but have been looking a round the forum on good days. The good news is that I have also spent my time wisely and discovered a different style hinge which I decided to try after many mock ups of the original hinge I made with no success. When I say no success, I really mean not enough improvement for it to work without scraping or binding. The alternative hinge I plan to use was discovered quite by accident and had been under my arm all this time as it is being used in a console to the side of my TV chair. I rarely open it but was looking for the lost remote controller and opened the lid and the penny dropped. I thought that discovery was going to be too easy, if it worked. I took the pair off my console much to my wife's disgust and installed them and made new mounting brackets. I could not be that lucky of course as they did not work either, but I could see their potential and have started modifying them to see if I could get them to move slightly differently and that is where I am right now. If this fails I will definitely walk away from the idea of a firewall hinge. Stay posted...
The above picture is the hinge I plan to use/modify now. Since it had no brand name etc on it, I thought I'd never find any information about it. However the power of the internet and the right choice of search words finally provided me with this picture which is identical to what I had in my console. I still don't know who makes them or where they are made, but I did end finding a supplier/agent who has them in stock. They are mainly used in caravans and RV's as a hinge for a bench seat that has a lift up lid that has a storage compartment below it. No need buy a pair for now until I am sure they will or wont work as required.
I have now made a card board mock up of the basic hinge principle and allowed extra length of arms and the option to re-position pivot points. As you can see by the number of puncture points in the card board I have just about turned it into Swiss cheese. Each time I felt that the pivot points were close to what I sought, I graphed the swing and marked hood angle at specific points. I have now chosen what I feel is the best possible scenario of pivot points and arm lengths. Next step is to replicate them in steel and mount them onto the car and see once the hood is attached whether it really does clear and work as anticipated.
Just for the sake of the record, attached is a pic of my final cardboard pivot points. You will note; Blue A - is the marked trajectories at various stages of movement. Important to success of this hinge was to keep the left hand end of the hood attachment point lifting and rising to clear the firewall edge. So too much lift at the RHS would cause the LHS tail edge to drag on the firewall. Green B - are the new chosen pivot point when compared to the original hinge. Pink C - are the location of the original hinge pivot points. Orange D - is the perimeter shape of the original hinge base plate. Yellow E - indicates a larger base plate size is required to the modified hinge for attaching one of the new pivot points. Purple F - is a hole in the cardboard used to place a pencil lead into and scribe the arc of each selection of pivot points. So the original hinge arc was scribed first as the base which I knew was not workable and then each additional point was scribe to compare any improvement against the original arc and that of its trajectories.
Well my friends, I am pleased to report that the new hinge works and the hood clears, so let the party begin... I am totally over the moon with this result. So high 5's all round I guess. There is still a lot of fiddly work ahead, but it kinder means more now, that I know it will work and anything I do now will be worth the effort. I guess the hinge pic and its mounting is self explanatory for you. It is odd but it works and not as pretty as my first choice. Pretty is a bit like BS, it only gets you so far...
Well, I now have my new stainless steel laser cut hinge components and I have assembled them. I still have some finish welding to do but for the sake of showing them here is what we have. One pic is of the prototype (with spring attached) and the other of the stainless hinge still requiring the spring. I am now in the process of trying to get the inner and outer skins to match up ready for attaching them to form one unit.
Thank you and I must say I am extremely happy with the outcome. Particularly the fact that the hood will now open up to 90 degrees and the back end rests on the radiator support rods. A stroke of genius some say, NO just plain old good luck for a change... .
How's the wife enjoying the cannibalized lazy boy or did you put it back together......I have a vision of her making dinner and your wrenching the chair apart while she's cooking coming back to a couple of cushions on the floor... The garage supply zone is expanding... Joking aside that looks awesome... I have to say I'm glad it's only a partial hood because that's such an awesome mill to hide...
Actually it is all back together now, it was the only way to get some peace, she was not impressed. I used those hinges to copy from and modify and then made a pair in mild steel which became my prototypes. Once confirmed in place that the hood would lift and swing up, then I got a set replicated in stainless steel from the laser cutting guy. Thanks for you kind words and the joke remains home regarding me pirating those console hinges. I have determined that they are used in RV's and Caravans if I wanted to purchase a pair but they were not going to do the job for me in their stock standard form. Hot rodding is a process of compromise and modifications most of the time, that is why I love being a hot rodder...
Fordillac! Wow, that's neat. Funny... I know what Flathead Cadillac engines look like. But looking at that picture of your engine, my brain assumes Ford. But then... wait... the heads look a little different. Is that a Cadillac engine? I'm studying the heads intently. Then the headers were like, "Hey dummy". Sent from my VS835 using The H.A.M.B. mobile app
Yes, the heads I think are physically larger and a little more squared off than the Ford items. The external markings on the heads indicate what year engine they came off. My heads for example are from late 1940's, while the block is early 1940's The way the exhaust exits the engine block is generally the give away that the engine is a Cadillac. Sometimes I just wonder why I am going to all this hood trouble to hide an engine that does not really need to be covered up...
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