Mounting Electrical Devices and Supporting Electrical cables

AaronD · Feb 19, 2026

I'll tell you what I did on my Catalina 22 and am currently doing on my Classic 26.

On smooth surfaces:
* When I expect to want to add wires to a bundle : Self-Adhesive Cable Clips - e.g. XHF @Amazon - re-openable so you don't have to cut a zip tie to add wires.
* Smaller runs where a zip-tie is OK : Cable Tie Mounts - e.g. XHF @Amazon

If under enough tension to possibly pull the adhesive off (after a few heat cycles):
* Drill and tap into liner (not hull!). For thick surfaces, you can use a bottoming tap to thread 1/4" or so without drilling through and leaving a visible hole.
* Screw through those adhesive clips to secure - 8-32 or 10-24 works pretty well.
* Threads in fiberglass need ~2 screw-thicknesses to meet full screw strength, but you don't care for this application
* I've found this easier to get consistent than pilot drill + sheet-metal screw in FG. YMMV.

On raw fiberglass where nothing sticks
* Interior cabinetry, where the liner or structure is thick enough: drill and tap as above
* Hull or thin liner (where you don't want to drill):
* Cut a small pad of fiberglass or G10
* Drill and tap
* Epoxy to hull - you can cover the back side of the tapped hole with a tiny bit of masking tape, so it won't fill with epoxy
* Screw a holder like those above into your newly-secured pad

Most of the same steps work for securing bus bars, terminal blocks, and light components.

At least that's been working for me.

Project_Mayhem · Feb 19, 2026

Dave0963 said:
What is a reasonable solution for supporting exposed cables? Am I over thinking this whole matter and screwing into the fiberglass/gelcoat is a sensible option?

Yes. If you're opposed to drilling try some VHB tape with something like this

dLj · Feb 19, 2026

Dave0963 said:
What is a reasonable solution for supporting exposed cables? Am I over thinking this whole matter and screwing into the fiberglass/gelcoat is a sensible option?

I've had more problems using adhesive to hold things in place on my boat than what screwing into the fiberglass brings. Although I don't screw into my hull, I will along other areas. If you have to run along your hull, I'd try what @Project_Mayhem says above.

dj

JoeWhite · Feb 19, 2026

I would hold the wire in place with blue tape on both sides leaving a one inch gap where the wire lays on the fiberglass. Then use white caulking in this gap to hold the wire in place. After the caulking drys, carefully remove the blue tape. The wire will remain in place. Use white wire to hide.

Project_Mayhem · Feb 19, 2026

dLj said:
I've had more problems using adhesive to hold things in place on my boat than what screwing into the fiberglass brings. Although I don't screw into my hull, I will along other areas. If you have to run along your hull, I'd try what @Project_Mayhem says above.

dj

To elaborate further, I only trust VHB and one other foam based tape. The other is a Chinese tape that would probably pull gelcoat off if you tried. I can look it up for you if you'd like. Using adhesion promoter or iso alcohol before VHB helps as well.

@Dave0963 I've taped cables to an unswept NYC street with gorilla tape. If you want something, quick fast and wont come off unless you want it to, try that. It leaves behind very little residue considering it's strength

dLj · Feb 19, 2026

Project_Mayhem said:
To elaborate further, I only trust VHB and one other foam based tape. The other is a Chinese tape that would probably pull gelcoat off if you tried. I can look it up for you if you'd like. Using adhesion promoter or iso alcohol before VHB helps as well.

@Dave0963 I've taped cables to an unswept NYC street with gorilla tape. If you want something, quick fast and wont come off unless you want it to, try that. It leaves behind very little residue considering it's strength

I'll have to try VHB sometime in this kind of application. But I've not found adhesives to do well over longer time periods especially if things get pretty hot - like in an engine room. But I'm certainly open to giving this a try sometime.

The Gorilla tape works great for temporary work. But I've found if you are leaving it in place for like a year or more - it degrades and it definitely leaves a serious residue...In the long term I'm talking...

dj

Project_Mayhem · Feb 19, 2026

dLj said:
I'll have to try VHB sometime in this kind of application. But I've not found adhesives to do well over longer time periods especially if things get pretty hot - like in an engine room. But I'm certainly open to giving this a try sometime.

The Gorilla tape works great for temporary work. But I've found if you are leaving it in place for like a year or more - it degrades and it definitely leaves a serious residue...In the long term I'm talking...

dj

You're absolutely right about VHB and heat. The best way to remove it is with a hair dryer or heat gun. I've found that the age of the VHB also makes a difference which likely backs up what you stated about long term usage. I have an old roll that's kinda useless at this point and a brand new roll. The new stuff works shockingly well, even on high energy plastics like polyethylene.

Gorilla Tape may not be as good as a quality gaff tape but it leaves a lot less residue than electrical or duct tape. The angle that it's pulled off makes a big difference. I usually end up with one spot of residue in the beginning and little to none after that.

@Dave0963 If you post a few pics of where you want to run cabling you'll likely get some excellent answers

dlochner · Feb 20, 2026

To run cables along the hull epoxy a small wooden block to the hull and use wire ties and mounts posted by @Project_Mayhem. The adhesive will hold the mount in place while you install a screw.

The wire should be supported every 18". Be sure to clean the hull and remove any paint before epoxying the wood block in place. Use thickened epoxy because the surface won't be flat.

Project_Mayhem · Feb 21, 2026

Dave0963 said:
Thank you for the suggestions, I'm happy to know there are options that don't involve penetrating the fiberglass/gelcoat.

I like the sheer simplicity of using blocking with tape-adhesive solution, and supporting every 18" will result in a clean/organized solution.

I will post images and thoughts when this project wraps-up. it's still cold and snowy where I am (Winnipeg, MB, Canada) so it may be a few months.

This forum has proven invaluable. Thank you for the thoughts and reasoning.

The pre installed adhesive will likely fail if you dont add another adhesive to the back. This could be VHB or a liquid adhesive. Prep is important if you are using double sided tape

brazenarticle · Feb 21, 2026

I've used Liquid Nails or PL construction adhesive to attach small blocks to the hull. It's good stuff, inexpensive and available everywhere. Clean the mounting spot with alcohol before gluing.
Side note - a box of pre moistened alcohol wipes are handy for cleaning and gluing, and also may be used for nausea if you or a passenger feels sick to the stomach.
Small plywood blocks with wire holders like the Ancor cable clamps allow multiple wires to be supported and still able to slide for repair, replacement or removal. Your future self (and anyone who eventually acquires your boat) will curse you if you use too many and/or too tight zip ties.
While spending money on boat stuff buy a decent label maker to mark which wire is what. Not sure anyone every complained about too many labels.
Old wire harnesses are a good source for multiple colors and gauges of wire but finding tinned wire in old bundles may be a challenge. When you need 3 feet of yellow with a red stripe, some dark blue and a couple feet of 14 gauge periwinkle old harnesses beat buying small rolls.

LLoyd B · Feb 27, 2026

Peel and stick cord cover will allow additional circuits without the need for a new tie wrap to be added for each new device that might be wanted.

Project_Mayhem · Feb 27, 2026

I'm about to mount LED strips in aluminum channels with VHB tape. Ask me in a year if held up

brazenarticle · Mar 1, 2026

Recently I added two long strips of COB leds behind the top teak trim on my C36. The circuitry is embedded in a long flexible strip so they are practically invisible. In other earlier uses with exposed chips I used the aluminum channel with a cover and the adhesive had to hold the weight of the channel. VHB (very high bond) tape can easily hold the weight. These COB strips just stick onto the boat.

Project_Mayhem · Mar 1, 2026

brazenarticle said:
Recently I added two long strips of COB leds behind the top teak trim on my C36. The circuitry is embedded in a long flexible strip so they are practically invisible. In other earlier uses with exposed chips I used the aluminum channel with a cover and the adhesive had to hold the weight of the channel. VHB (very high bond) tape can easily hold the weight. These COB strips just stick onto the boat.
View attachment 236760

I'm very confident that the VHB will hold up just an LED strip. In my case I put them in aluminum channels and made some custom mounts to get them at the right height and angle. The ones on the mount have limited contact with the boat. I'm guessing each mount will allow for 2-2.5" of VHB. I plan on putting one mount every 12-18". The aluminum channels are very lights so it should hold up. Mine are in a similar location as yours but I went for as bright as possible instead of accent lighting. I have a wireless dimmer mounted on the companionway, 12 to 24v converter (24v system avoids voltage drops on long runs) and the receiver/dimmer module is hidden away. I'll be posting pics in a separate thread when it's complete