I would like to find a hand crank worm drive strap winch with a 1" wide strap

[problematique]

I'm working on an archery project and would love to find a winch that is worm drive and hand crank. The 1" strap is the least of the requirements. There is something like I need at Harbor Freight but it's pretty big.

This isn't anything new. I'm just trying to improve on current designs. The part is called a draw board. The people that make the better ones seem to make their own winch. I would just like to have a work around for more budget minded people. The cheapies use a boat winch from a trailer but that doesn't give you the fine adjustment that a worm drive would give. Those also require letting a catch loose and maybe losing control of letting down the bow. I've seen some great ideas come out of this forum so I figured I'd try here. You guys may have seen something that may work in your experience. Thanks in advance for your time!

 

[brino]

Many cheap ratchet straps have pawls with a dozen steps.... Is that not a fine enough adjustment?

I know this uses rope not strap, but how about a multiple pulley system:
https://www.leevalley.com/en-ca/sho...-tackle-system-for-steam-bending?item=05F1301

That's it for now, but I will keep thinking......
Brian

 

[problematique]

Thanks for the reply. I could get fine tuning out of a different adjustment, but the ratchet by itself isn’t fine enough for precise work. The pulley idea wouldn’t allow me to have both hands free to work on the bow. Thanks for the idea though

 

[RJSakowski]

*I built one more than 30 years ago.. I didn't know it was called a draw board. I used a ratchet style boat winch on mine. I used it to measure the total stored energy in my bows. I had a JLJ compound with 70 lb. pull and 80% letoff and I wanted to know how it compared to my older bow. I graphed pull vs. draw and integrated under the curve to determine ft-lbs of energy. Somewhere, I still have those graphs.

I didn't shoot target except for practice . For hunting, the 80% letoff was sweet. At full draw, I was only holding 14 lbs. so I could afford to draw early and wait for the right moment to release. The one drawback of the large letoff was release was a lot more critical. I finally went to a mechanical release which improved my accuracy greatly.

Harbor Freight sells a worm gear winch for $35.

 

[problematique]

*I built one more than 30 years ago.. I didn't know it was called a draw board. I used a ratchet style boat winch on mine. I used it to measure the total stored energy in my bows. I had a JLJ compound with 70 lb. pull and 80% letoff and I wanted to know how it compared to my older bow. I graphed pull vs. draw and integrated under the curve to determine ft-lbs of energy. Somewhere, I still have those graphs.

I didn't shoot target except for practice . For hunting, the 80% letoff was sweet. At full draw, I was only holding 14 lbs. so I could afford to draw early and wait for the right moment to release. The one drawback of the large letoff was release was a lot more critical. I finally went to a mechanical release which improved my accuracy greatly.

Harbor Freight sells a worm gear winch for $35.

I wouldn’t have the slightest idea how to even set up the equation

This one will be used primarily for cam timing, draw weight and draw stop setup. We’re getting back to shooting competition because of my youngest son being interested. I just want to have the ability to tune as closely as possible.

I saw the one at harbor freight and am probably going to use it. I was just asking to see if anyone knew of anything that may be more compact. Thanks for the reply!

 

[Alcap]

If you end up making one ,you might find a awning drive something like this or ones used for greendhouses ( hoop house ) https://www.ebay.com/itm/2849309958...MItOj34eKt_AIVFonICh02zgdtEAQYBCABEgKLK_D_BwE

 

[OTmachine]

Might a right angle worm drive gear box work?

 

[RJSakowski]

The issue with finding an off the shelf winch will be cost. There are options out there but they are expensive. As I was trying to think of a a product that might use a low cost, more compact winch, I came up blank.

One possibility might be a windshield wiper motor. The one that I have uses an 80:1 worm drive. The gear is Nylon so you might want to proof test it before using. It will require some modification ; i.e. adding a drum for the winch strap and possibly some modification of form. To drive it, I would use a PWM control and a hand held remote with speed control, on/off and forward/reverse. If you are building a one of a kind for yourself, this would work. For a production solution, I think the cost would be prohibitive although you would have additional features that might justify a higher price.

I have no idea as to what vehicle the motor that I have came from bur some typical examples I saw ran around $50 new. To replace the 2" strap, I would get Nylon strap from a sewing supply store. You can get strap that would proof out at several hundred lbs. easily.

 

[francist]

I fell asleep last night wondering if a planetary gear set out of a cordless drill might offer any possibilities. Not the motor drive, just the gear transmission. Trouble is, aside from having taken one or two apart to see how they worked, I don’t know too much else about them. Definitely not an off-the-shelf item either.

-frank

 

[problematique]

Thanks everyone! I ended up buying the HF winch this morning. I’ll work around the size for the cost savings. It was built to pull 2k lbs. so i’d think that 80 lb. Draw weights should be safe. It has enough spool to convert it to strap.

Thanks for all the great ideas. I’ll look into them for refinement of the idea.