Scissor lift to full length? Tell me I’m wrong

[Trumpy]

I currently have this 3000kg scissor lift , great bit of kit, but I would really like a full length ramp . I don’t have room for a 4 poster so I’m looking at getting some longer channels made to extend this lift to accommodate the car on its wheels. 
I currently use a cross bar on the drop down ends ( as shown) to lift the car,  having checked with the supplier that it is safe to do so. 
(I feel lifting further along the car puts less stress on the chassis. )
So if I get two channels made from 5mm plate with a 60mm lip along each side at 2900mm long and bolt this to the existing ramp it will extend the ramp to accommodate the car . The new channels will strengthen the existing  ramp considerably and allow the car to be driven fully on . 
The actual contact points of the tyres are only 150mm beyond the current ramp (at each end. ) 

In my mind this will put no more stress on the current lifting points of the ramp as the load ( car) is still the same length and weight . 
please correct me if wrong ! 
Jacking individual corners will be much easier and safer with all four wheels on the ramp although I will still be jacking from the same points on the car .
Had anyone done something similar ? 
Or is there a better option that I have missed ? 
Pics seem to be upside down !. 
Dave 


 

[Lebro]

[Motorsport Mickey]

Genius…remember not to drill through the side flanges..,it will weaken the channel. Bolt through the horizontal surface, 2 each end should do it, the lift will not know anything’s changed. Post here after you’ve done it so I can copy it.

Mick Richards

[PodOne]

Hi Dave

I'm liking this idea as I'm tired of crawling under the cars having spent time jacking the corners up its still limiting. I wonder how much longer the extensions would have to be to take a TR6?

Think I've seen these scissor lifts at the NEC Restoration show a few years ago is yours powered using 13A or a 16A supply?

Andy  

[Motorsport Mickey]

3 hours ago, PodOne said:

Hi Dave

I'm liking this idea as I'm tired of crawling under the cars having spent time jacking the corners up its still limiting. I wonder how much longer the extensions would have to be to take a TR6?

Think I've seen these scissor lifts at the NEC Restoration show a few years ago is yours powered using 13A or a 16A supply?

Andy  

Mine is a Clifton Strongarm 3000 kg

 

and their spec is "The power supply for this mobile car scissor lift is 240V single phase. There is a 16A Cee-form male socket supplied with this lift. Requires 16A C or D type motor rated circuit breaker upgrade in your consumer unit."

Mick Richards

 

[Trumpy]

oh heck , that makes my garage look even more of a mess ! 
My ramp just works from a standard 13amp supply and lifts the car quickly and easily but I’ve not had anything heavier than the TR on it . 
A Tr6 has the same wheelbase and chassis as a 5 so It should fit just the same . 
If you are near to Lincoln Andy you are welcome to have a look . 
I found that lifting the car from points on the green ramp base caused the door gaps to open which I didn’t like leaving for any length of time . 
By raising the black loading ramps ( they lock up) I can use them as jacking points and the car shows no signs of being stressed .  I did check with the supplier that this was safe but may not be on different makes . 

Certainly getting the car up in the air is a game changer . 

We will see if extending the ramp to full length is ‘genius’ or not but I like the sound of it  . 
I will have the new ramp side flanges facing upwards to avoid having to cut out for the ramps frame cross bars . Or maybe I could reinforce the cutout area and retain the flat ramp ? 
Hope to have it done next week. 
I will post pics.

Dave . 
 

[Tim D.]

Have a the same lift. Nice idea regarding the extension. Also resorted to using 2 pieces of square section between the two platforms for my TR6. Not 100% satisfactory. Keep us in touch with progress. 

Tim

[Motorsport Mickey]

"I will have the new ramp side flanges facing upwards to avoid having to cut out for the ramps frame cross bars"

If you check your standard ramps you'll see they have a cut out near the front and rear, yet the advance and depart hinged ramps (which can be fixed at horizontal and used as part of the ram) are rated to take the load. So that is likely material dependant. Having a channel standing upwards 60mm is likely to get in the way sometimes whether it's stopping a cross car crossmember (engine support without gearbox eg) or other task.

My ramps are set into the floor (as are Tims, I pinched his sink it in the floor idea (on site builder £150 extra to other work) after seeing his excellent set up). I'd tried the "leave the ramps on the floor surface with wood at the front and rear of the ramps to increase the height of the parked car to sit over them" method. But after tripping over the remaining ramp width (about 15" either side) a couple of times when the cars parked there, flush floor fitting seemed a life saver...literally.  So the full length ramps for me would be with channel sides down onto the surface allowing the ramps to come up inside them before securing in use. I might even have an approach ramp formed on one end making them a foot longer. Thoughts ?

Mick Richards

Edited October 27, 2022 by Motorsport Mickey

[Bfg]

20 hours ago, Trumpy said:

In my mind this will put no more stress on the current lifting points of the ramp as the load ( car) is still the same length and weight . 
please correct me if wrong ! 

You are not wrong.  Aside from the additional weight of the two new channel pieces - the load on the ramp lifting points will be the same  ...as long as the weight distribution (when the car is on its wheels) also remains the same.  But.., park the car too far forward and the loads on the ramp's front pivots will increase.  And if you park it way-too-far forward then the ramp may have a tendency to topple over end.   Stop blocks permanently positioned on your channel extensions easily resolve this.  Bolted or clamped-on blocks at the back will prevent the car rolling back should you (or someone else) happen to forget to apply the handbrake. That may sound improbably but it can happen.  

Channel with their flanges upright will act as guides to position your car on the lift laterally, but such deep flanges would be a nuisance as the lift is used as table for tools & parts - they'd be like overly-deep fiddles (used on a sailing boat's galley work surfaces).  Perhaps more convenient to have them turned down but then use 1" box section rails on top ..as a guide for your tyres.        

 

Although not a car lift - I did similar extending, to support under the tryres, on a motorcycle lift. . .

I bought this Clark's brand of motorcycle lift, and found it critically lacking in common sense design and safety.  The motorcycles frame curves, brackets, engine sump and centre stand each got in the way of the bike sitting on the lifting pads. The design didn't accommodate different types of motorcycle either, for example my Norton Commando's side-stand bracket hangs down on just one side of the frame, and the cartridge oil filter hung down just in front of the rear wheel.  I appended to the lift with bolted-timber packers, but when lifted.. each of my bikes were terribly unstable to work on.  The force of undoing some bolts pulled the bike over.  It toppled once, when a rear wheel was removed and its overall balance upset.  Although no damage to me or the (400lb) bike was done ..it was a fight to get back upright, and definitely brought close to home the matters of safety.   
 

I modified the lift by adding a 3/4"-thick screwed n' glued plywood box over it. This was too short in itself so I extended it forward (with a deep I-beam in timber) which kept its overall footprint as tight as practical.  My 'extensions' are securely bolted to the lift.  I can push the machine up a ramp onto the box, and then raise the bike onto its centre stand.  To balance (side to side) and secure the bike up there, especially when hydraulically lifted, I added oak upright posts ..to embrace the front wheel. Timber blocks are used to accommodate different tyre widths, and there is a tyre stop between those, at the bottom. I use a large G-clamp around those posts to pinch them to the front wheel. That all worked very well.

The lift and its lock (to avoid the hydraulic ram from loosing height) work as standard, except that the lift is now in-line with the bike rather than coming in from the side.  But still, the small footprint of this bike lift, felt uneasy (threatening to topple front end forward).  I resolved this by simply having two stout (wedged & clamp-on) legs, from the front upright-posts down to the ground.  I could now work on my (and customer's) bikes at a sensible height all day long (I use a swivel office chair with no backrest as a stool). The flat bed of the box is a convenient bench to place tools and parts, and even a sump-oil drain container. And I could safely remove the rear wheel with the bike lifted well off the ground.. for working on the rear wheel, brake or final drive (these Sunbeams are shaft drive).

As configured, using an old packing case - the (unaltered) Clark lift is positioned a little too far back. And so although it lifts up OK, when lowered the hydraulic ram tends to jerk down in steps. It's fine when lowered very slowly, although I suspect it would be a smoother action had the lift had been further forward.  The Clark lift is on wheels - so I could pull the bike out into the middle of the garage, or to move it to one side or another for clearer access, or for parking it out of the way. As a safety precaution I did use a winch / tie around the roof beam down to the bike's handlebars .. Just in case the worse scenario might happen - it would give me time to correct things or to get out of the way. That's been 'peace of mind' and thankfully not yet been needed.   

So the lessons learnt were ones of balance and stability. Positioning & securing the bike onto the lift  ..And extra support legs down to the ground - so that the whole lot was safe to lean / push against when struggling with overly tight bolts, or when the balance of the machine itself changes significantly.  In the case of your lift and car - perhaps spares in the boot, tank of fuel, and engine lifted out. Or else a different car.

Hope that helps,

Pete.   

 

 

Edited October 27, 2022 by Bfg

[Trumpy]

I’ve been doing some measuring and head scratching and decided to flip the new ramps so the folded flanges face downwards as the original ramp . 
As you have both said it’s much better to have a flat surface. 
I’ll double the thickness of the flange with a welded plate where the cut outs are . Should beef it up nicely. 

nice bike btw Pete ! 


 

[Eddie Cairns]

On 10/26/2022 at 9:01 PM, PodOne said:

Think I've seen these scissor lifts at the NEC Restoration show a few years ago is yours powered using 13A or a 16A supply?

Andy  

Andy,

Assuming you have a good capacity electrical supply to your garage and a consumer unit fitted in the garage, my guidance after wiring up a number of two post and scissor lifts is as follows but I advise I have no electrical qualifications.

The mcb breaker capacity and design curve can be a bit hit and miss, let’s assume a 16amp mcb.

Type B should trip at 3 times it's rating, in this case 48 amps for a B16.

Type C should trip at 5 times it's rating, in this case 80 amps for a C16.

Type D should trip at 10 times it's rating, in this case 160 amps for a D16.

General advice is that a D16 breaker may cause the main consumer unit to trip before it will and in reality, needs a 200 amp supply into the premises. Not in a domestic environment!!!!!!!!!!!

I have known some lifts to have no issues being fed via with a B16 mcb in the consumer unit, in most cases I have used a C16 mcb for friends lifts with no issues. I have known a good few lifts to run off a 13 amp plug in commercial garages and a few to have a bolt in place of a 13 amp fuse in the plug, not in my view a safe installation!!!

On my own 2 post lift, I had a C16 mcb installed in the consumer unit and as soon as you asked the 2 post to lift a vehicle it would trip. A change to a C20 mcb solved the issue. My own lift pulls down the garage voltage when operating and the nearest fluorescent tube to the lift which is the last in line of 6 double tube fittings goes dull during lift operations. My 2 post has an electric motor has an 80 amp stall current. It is the most current hungry lift I have used. All wiring was to the 18 edition of the electrical regulations. It has been working without issue since December 2013.

Last week, I wired up a friend’s garage and his lift was being run via a 13 amp socket and three flex extensions via the only mcb in the garage consumer unit, a B20 mcb. It was tending to trip the B20 breaker via the many extensions. I could not get a C rated breaker locally and he was hot for using his lift “NOW”. I sourced a B25 breaker locally, the lift and sockets are now hard wired via separate mcbs. C16 is 80 amp trip, a B25 is a 75 amp trip. He is a happy camper!

Wiring a Fixed Single Phase Lift

To finish I would use a C16 mcb in the garage consumer unit via 4mm2 twin and earth cable to a fixed lift control unit in the first instance and take it from there.

For short cable runs 2.5mm2 cable will suffice but for the small increase in cost, I would always use 4mm2 cable for this duty where possible.

Wiring a Mobile Single Phase Lift

I would use a C16 mcb in the garage consumer unit wired via 4mm2 twin and earth cable to a 16 amp commando socket on the garage wall nearest to where the lift will be used. Then equip the trailing lead to the lift control unit with a 16 amp trailing commando plug via 4mm2 arctic cable to the lift that may be moved about the garage. Or the trailing cable that is supplied by the lift supplier. For short cable runs 2.5mm2 flexible cable will suffice but for the small increase in cost, I would always use 4mm2 cable for this duty where possible.

 

[PodOne]

Hi Eddie 

Thanks for all the advice!

So happens the house consumer unit sits in the garage. It's also split given the load and multiple ring circuits for the house as I like everything split. 

If I was to get a scissor lift I think I'd put it on a separate consumer unit/supply even though the cable run to the lift would be quite short. That way it keeps the Mrs's happy as hopefully there would be no tripping out.

Just need a nice exhibition discount plus my brother wants one which might help.

Andy

[John Morrison]

Hi Dave,

In my mind this will put no more stress on the current lifting points of the ramp as the load ( car) is still the same length and weight . 
please correct me if wrong ! 

I've followed this post from the beginning and believe me I fully get where you are coming from, before I eventually shoe horned a four poster into my domestic garage i looked at a myriad of different ways to raise the car, so I do get your thinking, but I think your proposal is flawed.

The car is the same weight- agreed, but that weight is not evenly distributed front and rear, I've looked but cannot find front axle laden weight v rear axle laden weight, THATS WHAT YOU NEED TO KNOW.

I think you would need to fit your longer ramps not centred over the existing but offset, if you don't the greater weight acting through the centre line of the front wheels will impart a turning force greater than will be countered by the weight acting through teh centre line of the rear wheels, as this is outside the original base of the lift, you will be imparting a lifting force on the fixings of the lift at one end.

I would ask around, folk cleverer than me, but if I were you I would get the front and rear axle weights of your car, easily done at a local public weighbridge,

Drive the car partly onto the weighbridge leaving the  rear wheels  off the bridge, get that weight.

Drive the car fully onto the bridge, and get that weight, the total weight, then

Drive the car over the bridge until the fronts are just off the bridge and get that weight, then you will have the accurate weight front to rear, then you can look at siting your new runways so that when the car is on the lift the weight is even and the car in balance.

John.

[Motorsport Mickey]

+1 for the way John describes the weighing process to obtain a split weigh of front and rear axles, and also the differentials in imposed weight on the lift and any "overramp" channel added onto the scissor ramps caused by the cars difference in front to rear weight distribution. When weighing you may well find there is a slight difference between adding the front and rear axle weights together (normally more) than the "all up" weight of the car when parked upon the weighbridge, that's caused by the small error naturally occurring with the car positioning to leave one of the axles on the weighbridge, that's not a problem.

However in your case the lift manufacturer has supplied the lift with "advance and depart" ramps and these ramps are strong enough to take the weight of the car or indeed have the car lifted on these areas as the manufacturer confirms (Strongarm confirm this with my lift). Your photos above show the car positioned with the front and rear tyres just contacting the finishing edge of the hinged ramps meaning the imposed load is going onto the scissor platform through hinges and onto the lift in the manner the manufacturer is happy with (maybe a call to them to confirm if you haven't already done so). I notice your scissor lift has a shorter ramp area at the front (overhanging the lift attachment) than the rear, loading the lift more highly to the rear with overhang. Happily, the TR has a normal front to rear bias in axle loading showing about a 55% - 45% split front to rear which mimics roughly the loading on the ramps ie more weight on the shorter overhang front in the event the car is loaded in the same way as shown in your photo.

Mick Richards      

[Bfg]

12 hours ago, John Morrison said:

if I were you I would get the front and rear axle weights of your car, easily done at a local public weighbridge,

Drive the car partly onto the weighbridge leaving the  rear wheels  off the bridge, get that weight.

Drive the car fully onto the bridge, and get that weight, the total weight, then

Drive the car over the bridge until the fronts are just off the bridge and get that weight, then you will have the accurate weight front to rear, then you can look at siting your new runways so that when the car is on the lift the weight is even and the car in balance.

why not do things the long-way-around way John !

Seesawing the channel sections on centrally positioned narrow block(s), perhaps just 1" high ..and positioning the car to be balanced - then measuring axle to block dimension, would possibly be a little quicker - seeing as the channel sections are already available.

However, perhaps still more convenient ;  the weight distribution of the TR4A is said to have been F. 50.6% , R. 49.4%,  with a kerb weight of 2,358 lb / 1,1071kg, with oil water and half a tank of fuel. (AUTOCAR  28th May 1965)  ..so for all practical purpose 50:50 weight distribution for the TR4A.   Btw., the TR4, with just 1.5 gallons of fuel in the tank, was recorded to have R. 54% , R. 46% weight distribution (Motor  magazine July 11th 1962).

The ramp was (most likely ..but worth checking) made to take many different (compact to mid-size) cars of very different weight distributions that any owner may use it for, and so the undoubtedly-generously designed and tested safety margins would accommodate a moderate amount of 'imbalance'. As Mick has pointed out the ramp appears to have already been configured for the imbalance of FWD cars, so I'd suggest Dave extends his lift equally, a foot or so both front and rear. 

Pete

 

 

Edited November 5, 2022 by Bfg
TR4 weight distribution added for clarity

[Waldi]

From a static point, as long as the centre of gravity of the load (the car) does not change with this modification abd remains within design criteria, it would not make the lift unsafe. 

The longer ramps however create the possibility that the load is more off-centre, and this can be dangerous (like when an unaware person tries to lift something heavy out off centre. 
Example: lift an engine on the end of the elongated ramps.

I would be hesitating to modify a “small foot print” support such that it allows a load to be lifted outside the COG.

Just my thoughts.

Waldi

 

[Motorsport Mickey]

Good supporting thoughts here from everybody BUT maybe we are a little too pessimistic. The way I would regard it is the lift is rated at 3000kg lift capacity, it is tested under the LOLER system (safety rating for items used in lifting, chains, ropes, cranes, lifts etc) for safe lifting here in the UK which means it is rated as being safe with a 25% OVERLOAD !. Hence within it's 3000 kg plus 25% safe overload window of 750kgs I think a 1100 kg TR with a 605kg front axle loading (55%) and a rear axle loading of 450kg (45%) and the centre of gravity misplaced by 12" has ...bugger it,... plenty in reserve as a safety margin.

Mick Richards

 

 

 

[Bfg]

+1

 

 

 

Edited November 5, 2022 by Bfg

[stuart]

FWIW Your local MOT stations brake rollers now show the weight on each axle when doing a brake test. My 4a (solid axle version) actually comes up as 50/50 split.

Stuart.

[boxofbits]

1 hour ago, stuart said:

FWIW Your local MOT stations brake rollers now show the weight on each axle when doing a brake test. My 4a (solid axle version) actually comes up as 50/50 split.

Stuart.

It probably would Stuart as someone weighing around 90kg operating the brakes would almost certainly add rear weight especially on a TR driving position virtually over the rear wheels. 
 

I think Mick is absolutely right. The manufacturer could not possibly take the risk of the car not being bias weighted correctly over the ramps. More to the point,  is the whole assembly correctly weighted or fixed into the floor!

Kevin

Edited November 5, 2022 by boxofbits

[Trumpy]

Hi folks , apologies I’ve got a bit behind on this . 
I’ve drawn a v childlike pic of the ramp . 
My take on this is still that it makes no difference, with or without the extensions. 
Imagine the ramp was the chassis of a car . Probably a longer and much heavier car . 
I have now temporarily fitted the new ramps to try them . Surprisingly they do bow v slightly,  although once bolted to the original platform I think it will stop that .  I’m going to add more bracing to be sure . 

[Trumpy]

Removed as upside down 

 

Edited November 7, 2022 by Trumpy

[Trumpy]

And again 

 

Edited November 7, 2022 by Trumpy

[Trumpy]

 

 

Edited November 7, 2022 by Trumpy

[Lebro]