Winch conversion from wire to chain sprocket

[thehomeengineer]

Hi All

I am in the process of building a motorised trailer mover and purchased a new 4500 lbs winch as the drive unit. Like most of my homemade projects I try to keep the cost to a minimum. However this was a brand new winch so the budget is blown . Other new items include a battery chain sprockets, wheels and bearings. I already had a length of 3/8 pitch chain.

The first issue was how to connect the smaller drive sprocket to the cable spool on the winch as the sprocket was a smaller diameter than the spool. So decided to cut the spool in half and mount a second boss to the sprocket and rejoin the two half’s of the spool back together on either side of the bosses.

The winch was taken apart and in my mind this was going to go one of two ways as this was a new perfectly working winch about to be butchered. So nervously the spool was setup in the lathe and parted off, support at the tailstock end with a pressure pad to prevent the spool from coming out of the 3 jaw chuck. Success the two halves were then machined to length and bored.

The sprocket was then modified and and both the spool halves and the sprocket drilled and bolted back together and refitted to the winch.

The photos will hopefully clarify modification.



Spool with wire removed.

Winch motor and clutch assemblies.

Parted off and part assembled sprocket ready for finishing.

Modified sprocket and bored spool halves

Winch back together

New drive wheels and trailing support wheels. ( no expense spared on this project )

Next job will be to mockup the assembly and build the chassis.

Will keep you posted on progress and build as it happens.

Thank you for viewing
The Home Engineer

[ductape]

Doing it this way instead of simply attaching the sprocket to the output shaft of the gearbox retains the winch clutch and allows the cart to be powered or freewheeled as needed. Clever idea, and nice work.

[DIYer]

Thanks thehomeengineer! We've added your Winch Spool Modification to our Trailers and Towing category,
as well as to your builder page: thehomeengineer's Homemade Tools. Your receipt:

Winch Spool Modification by thehomeengineer

tags: trailer, modification, winch

[thehomeengineer]

Doing it this way instead of simply attaching the sprocket to the output shaft of the gearbox retains the winch clutch and allows the cart to be powered or freewheeled as needed. Clever idea, and nice work.

Thank you for the comment. I didn’t want to create too much damage to the winch just in case the trailer mover isn’t a success. (I am building it a bit on the fly). If not successful I can put the winch back to its original intended purpose. Simply make a spacer piece and bolt the two halves together and reattach the wire rope.
Many thanks again for the interest in this project.

[imohtep56]

How are you controlling the motor speed and direction?

[thehomeengineer]

How are you controlling the motor speed and direction?

Hi and thank you for your interest in this project. The winch was supplied with two remote controllers and a hardwired hand controller. The chain sprocket ratio of 3:1 19T:57T If I have worked it out correctly the movement of the trailer at 2.2tons should move at 0.5m/min not fast but only moving short distances. The sprocket ratio should also increase the torque of the mover so should cope with the weight (we will soon find out)

The photo below shows the mockup of the chassis. I have tried to make it as simple as possible be also be able to take the weight of the trailer.

[thehomeengineer]

Every day is a school day. I really enjoy building projects like this, researching how others have overcome the same problems, what is commercially available and developing designing and improving something to try and meet my needs.

However doing this just highlights the void’s in my engineering knowledge. Like most projects starting from scratch can be quite daunting. Especially when it is your money you are spending and that little nagging thought in the back of your head (I hope I have got this right) Already on this project there has been mistakes that I have had to overcome. (Great feeling when you do solve them) but I thought I would share a mistake I did make which could have been expensive.

Awhile back I purchased a load of new old stock chain from an auction (only about 20 years ago, because one day that will come in handy for a project) There was quite a bit of chain and eight boxes of 3/8 Renold chain. (Useful size I must of thought, 20 years ago)

As previously mentioned I have purchased several new items for this project, one being two 3/8 pitch chain sprockets. When they arrived they looked right, correct part number etched on them, correct number of teeth etc. Now normally I would have tried the chain on the sprockets to make sure they fitted. Oh no! not this time, I will be clever and leave the chain in the sealed box so the chain doesn’t get dirty etc
Machined the sprocket to fit winch and put all back together, ready to go. Had a bit of a mockup and then the sealed box got the better of me and I had to try the chain on the sprockets.

photo below shows the dimensions of the pitch on the boxes
Clearly states 3/8 pitch

You guessed it the chain wouldn’t fit, so opened another sealed box same result. Oh dear either I have purchased some dodgy chain from auction and that’s why I got it cheap or the sprockets had to be incorrect.

On researching chain I didn’t realise British Standard chain is different to American Standard chain. Please forgive me if you all knew this but I didn’t. It turns out that 035 chain is American and 06B-1 is British. Both 3/8 pitch but other dimensions are so different.

In my defence I don’t often need to use chain drives for projects. In the past I have purchased chain and sprockets at the same time, so was unaware of the issues that I was about to face having this void in my knowledge.

Fortunately with in the lot I purchased (20years+ ago) there was a 10m length of Standard British chain to suit the sprockets I had purchased.

So next time I decide to use a chain drive with 3/8 pitch I need to purchase ASA sprockets which are readily available in the UK

hope this helps not to fall into the same trap as me