Thread: Dumb Waiter/Goods Lift Track

I'm just taking a stab here -- how about garage door tracks? (I dont know about the size your asking for , but I have 2 tracks laying on the side of my house and I noticed that I could link them together and make them almost 16 feet long.)

I agree with turbo TA
Have a look at panel lift garage door tracks. It might be cheaper to change your rollers so that you can use the door tracks than trying to find channel to fit the rollers you have. The panel lift door tracks use rollers about 50 - 60mm od (I'm only guessing as I don't have access to a door anymore) The track itself is like a "C" section which the rollers fit into.

regards
bollie7

How about Unistrut. I think they have rollers to fit as well. Been a while since I looked though.

http://www.unistrut.com.au/

Nev

Conventional unistrut and garage door track are C shaped and designed for significant weight hence are heavy, but all you need is a lightweight U shape. I would suggest an aluminium U shaped channel from Capral.

Something like a 25 mm wide x 20 mm deep x 1.6 mm thick x 6 m long
part number 863364 - I have their complete cattle dog if you need it.
No prices buy my guess is not too bad. If you want less (but pay more) try a big green hardware store!

Originally Posted by Matt2u1

they will need to resist the pressure of the cart wanting to tip forward.

Originally Posted by BobL

Conventional unistrut and garage door track are C shaped and designed for significant weight hence are heavy, but all you need is a lightweight U shape. I would suggest an aluminium U shaped channel from Capral.

How would a U shape prevent the forward movement? Unistrut comes in light, medium and heavy. The system is designed more for overhead mounting but with a little thought should be suitable. I would be inclined to mount four rails (two each side) rather than two back rails.

Nev

Here's a quick diagram of what I'm talking about. Top view.

I just need the C-Channel. The channel will provide a guide vertically and stop the cart from tipping forward. I have seen this type of set-up used in commercial units. The cable will attach to the top roller structure.

Originally Posted by Matt2u1

Here's a quick diagram of what I'm talking about. Top view.

I just need the C-Channel. The channel will provide a guide vertically and stop the cart from tipping forward. I have seen this type of set-up used in commercial units. The cable will attach to the top roller structure.

I call that U channel, C channel, has small lips either side of the 4th face.

most of the aluminium suppliers will have various U channels.

capral, smart, and so forth.......the problem is that most of the channels will be even metric outside dimensions.....like 25x50 x 3mm which makes the inside 46mm...or such

have you thaught about running pairs of wheels either side of a RSJ

or running wheels or rub blocks on the outsides of the carrage against the shaft....like they do in real lifts.

We..a builder mate of mine, built a dumb waiter for an accountant.......we just ran rub blocks on the outside of the carrage.....top and bottom corners all 4 sides......against a tubular lift shaft.....and drew the carrage centraly on a chain.....this was only small....took a plastic crate of files.

if you draw centraly on the carrage ther is no tortion.

if you are wanting to run more like a construction lift........pilling an adjustable monkey up an RSJ or U beam would be easy.....then you pull up the outside of the beam.

If you have your heart set on the channel.....you might have to machine your wheels to your channel...if you want a good fit.

BTW... what are you using for a lift motor?.....and I trust you have interlocks on the doors..

cheers

Thanks for you constructive feedback Soundman.

I have a 400kg 240v hoist (apparently handles 400kg or 800kg on a loop). The most I expect the thing to lift is 100kg.

The lift shaft is lined with 12mm ply. Inside dimensions 990mm wide and 595mm depth. The height of the shaft is 3 levels. The hoist will be mounted at the top on a steel pipe that goes across the width of the shaft. Pipe is 48mm OD thinckness 4mm (should be strong enough).

The door locks are electronic latches, and door handles are standard key locking. I have done most of the cct design, just haven't fabricated any electronics yet. Will be PICAXE based.

I had thought about the I beam idea. The problem is the shaft is built (house is almost finished) so getting it in there would not be easy.

I can mount the hoist to either lift centrally or at the back of the shaft. Maybe I should take some photos and post them. I am open to any ideas, I only spent $15 on the wheels so I don't have to use them.

I think I know the winch you are talking about.....wire rope hoist right?

I'd go centre pull.....just so much easier.

you could run rub blocks or wheels.....as I mentioned.

you could still use your wheels, just mount them above and below the carrage...of course you will need more wheels.

The rub blocks we used were just teflon furniture slides.

ours was only a two floor thing...the winch is a panel lift door opener.

we ran the chain over the sprocket in th normal housing...used another sprocket out of the kit to take the excess over to one side of the shaft...where it went down a length of plastic pipe......we hung a steel bar counter weight in the tube.....very close in weight to the carrage....a little heavier I seem to remember.

the door opener provided all the controll gear and limit switches we needed.....even a place to connect the door interlocks.

adjusting the stop height top and bottom was a bit of a fiddle and you only got about half a dozen runs up & down the shaft as the motors are not 100% duity rated and the thermal cut outs do their thing....so you wait for it to cool and go again...till it's right

I should write it up as a handyman article.

cheers

I may be able to help you, if I'm not too late.

My business used to put together very simple low-cost kits for dumbwaiters in the early 1980s, for competent tradesmen to install for themselves, till the Qld Machinery Dept warned me off, about 1985.

Since then I've stayed in the industry (now semi-retired in my 70s and working from home) but now my kits include everything you need to be street-legal, based on Australian Standard 1418 "Platform Goods Hoists", which is a lot less demanding than the Lift Code AS 1734. That costs a couple of grand, just to buy the set of books it's written out in.

Just supplied a big 1 tonne platform goods hoist last winter for the RSL extensions at Ayr near Townsville, for a fair bit less than their other quotes.

I'm at Mt Gravatt and happy to have a look at what you've done so far, and give you any advice you need on saving yourself from possible future dramas - for free of course.

Thanks Bill

I will take a few photos tomorrow and post them with the plans.

I have purchased a cable hoist that's rated to lift 400kg on single strand.

I don't have tracks or a cart yet.

How far is it from the upper floor to the lower floor, and are you planning to serve 2 floors, or 3?

Those winches (which I also sell) run illegally too fast for dumbwaiters
(10 mtrs a minute) so you have to double-fall the wire rope with the pulley block supplied. That halves the speed to an acceptable and controllable 5 mtrs a minute (The Code says not over 6m/min) but it also halves the reach.

If it's now not long enough, I take off the original wire rope and fit a longer length of a thinner high-tensile rope that's still strong enough when doubled back to take the actual load, and doesn't over-fill the winch drum when the car is up.

I'll be interested to see your dimensions etc.

I've just seen this dumb waiter thing and I am REALLY interested,
I am also building - starting in January - so I have some time to sort it out. So for I've checked out pricing from local suppliers K$10-14 and from China K$5-6.
I've built a few hundred vertical lift doors for freezer/chillers. These all have counterweights (up to 200-500 kgs) and Robot or Dorma drives - expensive. I thought I could do this little job for my new house at a fraction of the cost - but it is a complicated little beast to do properly. My current line of thought is to use a 240v chain or wire hoist, pulling the ~450x~450 car on centre of gravity, some simple nylon slides on steel angles each side. BUT - I haven't found a control box to do it.
Soundmans builder mate had a couterweighted solution but naturally the counterweight can never be the correct weight in this application (as the payload varies from nil to 100kgs) so the little garage door opener is bound to heat up quickly!
The old Bill's kit idea sounds good to me.
Can you let me know how things have progressed? What is the go here fellas?