Long Bolts for winch install

[sail_girl91]

Hello everyone! So I am trying to reinstall the winches on my sailboat. These are the winches that the previous owner had removed. On the deck, just outside of the cockpit is a mounting block, which sits about 4-5 inches off the deck surface. The problem I'm having is that in order to have bolts that can go all the way through that block and through the main deck/supports in the locker below, and through the backing plate, my machine screws need to be at least 8 inches long! I am having a hard time finding stainless machine screws that are this long (and don't cost $13+ each!). Has anyone else had this problem? I thought about using stainless steel threaded rod and nuts on either end, but I'm not really sure if that works, since the nuts won't countersink into the holes in the winch base. The winch is an older Lewmar 40.

[Charlie]

I had that problem in Mexico. I ended up buying a piece of threaded rod and then some machine screws. Cut the heads off of the machine screws and had them welded on to the end of the threaded rod. The bolts I needed were 12" long and I couldn't get them anywhere. I think that $13 is going to be the rate you are going to have to pay.

[atoll]

try find them online you might get them a bit cheaper.
otherwise the previous posters solution sounds good.

[Island Time O25]

Last time I needed extra long ss bolts I used these guys. Not really cheapest (but cheaper than WM and more assortment than either HD or Lowe's) but they had everything I needed under one roof. Even though their outlet is nearby they said they prefer to do business online and don't stock as much in their physical location. They also give a decent discount on boxes of 25 so that ss 7/16X8' is $12 a piece but under $8/piece for box of 25. Anything 6" or less is considered "standard" and is much cheaper (I was almost tempted to do a hurumpah drum roll after this sentence)

www.boltdepot.com

[SVJennie]

Here is just one of several ways to help solve your problem.

You didn't state the size of the machine screws, and with that in mind, it may be cheaper and easier than what I am suggesting here to purchase the fasteners as has been suggested at boltdepot. You might also try Fastenal.

Keeping in mind that a winch base invokes far more of a sheer force compared to tensile, you don't need to have really long bolts, but the block has to be well secured to the deck. That being said, you can screw/glue the block in layers and at a thickness below the winch you feel comfortable with (1 1/2" should be sufficient) install STAINLESS tee nuts to match the windlass bolt pattern. Then you can use shorter machine screws to secure the winch.

A simpler way would be to fasten the support block with threaded rod, then use shorter heavy fasteners to secure the winch. People with fiberglass boats and aluminum masts seem to forget how winches were/are attached to sitka spruce masts, it being a light soft wood.

I have a wooden boat with wooden masts and use either heavy wood screws or flat/oval head sheet-metal screws. A number 14 screw is approximately 1/4".

Incidentally, Fastenal has oval head sheet metal screws on clearance (if still in stock) that are cheaper than plain steel. I was able to purchase a good variety at an incredibly low price. There is often, but not always enough clearance above the base of a winch to use oval head screws.

Another way would be to imbed a drilled and tapped plate in the "tower that supports you winch.

Is it about time, skill or money? That is a choice you will have to make.

All the best

[secrabtree]

Originally Posted by sail_girl91

Hello everyone! So I am trying to reinstall the winches on my sailboat. These are the winches that the previous owner had removed. On the deck, just outside of the cockpit is a mounting block, which sits about 4-5 inches off the deck surface. The problem I'm having is that in order to have bolts that can go all the way through that block and through the main deck/supports in the locker below, and through the backing plate, my machine screws need to be at least 8 inches long! I am having a hard time finding stainless machine screws that are this long (and don't cost $13+ each!). Has anyone else had this problem? I thought about using stainless steel threaded rod and nuts on either end, but I'm not really sure if that works, since the nuts won't countersink into the holes in the winch base. The winch is an older Lewmar 40.

I think that Charlie's solution for 12" long bolts is humorous. I can't conceive that the cost of the welding would be significantly less than $52 (four $13 bolts). Plus there'd be the additional cost of the fuel in chasing down a welder. And the finished product would probably be of lesser quality than manufactured bolts (Unless you purchased the services of a certified welder). I have a Lewmar windlass on my boat that I installed more than a decade ago.
As you describe the situation of the supporting structure, IF the wood block is firmly attached to the boat, four lag screws would probably be sufficient. The loading should be shear only.

[secrabtree]

Sorry. I just re-read the original post and relized you asked about mounting a winch, not a windlass.

[UNCIVILIZED]

It's kind of been mentioned, but to clarify.
- Get a metal or G10 plate, & drill & tap it to accept the pattern & size of you winch's bolts.
- Drill said plate for some of that long, all-thread.
- Using the all thread, bolt the plate through everything, including your belowdecks backing plate. Bedding it of course, & hiding the nuts on top of the plate underneath of where the winch will be. Assuming that you just don't simply tap this plate for the long pieces of all-thread.
- Bolt the winch onto your pre-tapped plate.

Ensure that all bolts are bedded properly if needed. Ditto on using Tef-Gel or Loctite on all of the fasteners, depending on their location & function.
For instance, Loctite the ones holding the winch onto the tapped plate. And yes, when correctly selected in terms of type, & properly applied, Loctite will prevent seizing, in addition to making sure that the fastenings stay securely in place.

The other option would be to, fully bolt down your base plate. And assuming that it's strong enough to take the full winch load. Cut some window pockets through it's sides, into which nuts & washers for the winch mounting bolts can be inserted.

[tbkahuna]

You don't need to go all the way through with 1 bolt. Cut the mount in half. Put a plate or use large washer to run shorter bolts through one half of mount. Secure the winch to this half. Then join the two half with longer rod that you can can use mount as well. Or counter sink, bolts in both directions to attach both winch and mounting surface.