On my bicycle I need to attach a plastic part (cadence sensor) about the size of a quarter to an aluminum part (crank arm). Both parts are flat.

I used the 3M double sided tape supplied with the plastic part, but that 3M double sided tape is a millimeter or so thick, and that takes up the tiniest bit of tolerance that I have and causes interference. I need to attach these parts together with double sided tape that has the thickness of Scotch / masking / duct tape, or use an adhesive.

The tape or adhesive needs to be similar in strength to the 3M outdoor tape. The parts will be in motion, but nothing extreme, and they will get wet on occasion. However, it also needs to be something that when I need to remove it, while maybe not super easy, it needs to be possible and leave no damage on the aluminum part. If it hurts the finish on the plastic part, no big deal.

What do I want to look for / buy at the hardware store?

Dab of 3M 5200 will work. It’s for marine industry, works when wet and has a littl flex .

But buying a whole tube would be too expensive.

Do you have any silicone caulking or the like? Try that.

There is a foam-backed tape, made by 3M or maybe Scotch brand that seems to be what you are looking for. It is about 1/8" thick and has adhesive on both sides. In the tape display at your local Deep Homo or Lowsers store.

Alternatively, maybe try high-strength adhesive-backed Velcro for quick mount/dismount capability.

OK, so neither of these can be expected to meet the clearance requirement. Seems like that pretty much leaves you to glue, which will compromise the easily-removed/replaced requirement. Maybe thin tape that, instead of being double-sided and applied between the parts, it would be wrapped around them, and if you're counting crank turns, you could probably move out the crank to the pedal, and get more frame clearance that way...

I think I would use JB Weld for Plastics.
https://www.amazon.com/J-B-Wel...83795260945725&psc=1

I always keep some of this in my tool chest.

YMMV

quote:

Originally posted by architect:
There is a foam-backed tape, made by 3M or maybe Scotch brand that seems to be what you are looking for. It is about 1/8" thick and has adhesive on both sides.
<snip>

As I understood it, holdem said that 1 mm was too thick.

Gorilla makes a great double sided tape. I’ve used it inside a shower door to hold a drip edge in place as well as in outdoor applications with good results.

Take a look at the small tubes of Flex glue ... a couple months ago used for the first time for a small repair and surprised how strong it was. Maybe this will work.

E6000 adhesive bonds very well and can be removed with no damage to the surface. The sensor would have to be positioned and held in place (tape?) while the E6000 sets up. I'd give it a day to be sure. A thin layer is all you'd need.

I agree with the 3M 5200. You can buy it in 1 OZ tube. Store it in a baggie in the refrigerator and it will last a while if you need to use it again.

JB Weld. You can buy it all over, strong and will be thin between the parts.

Very small zip type wire ties. The very small ones approx 1mm thick. .................... drill sgt.

100% silicone caulk, like this tube of GE clear for $6 at Home Depot. Way more than you need, but it works great as an adhesive, and can be pulled apart later and peeled off pretty cleanly.

https://www.homedepot.com/p/GE...lk-2708911/100091111

You could try double sided woodworking tape. Amazon, or any woodworking specialty store.

I’d try a drop of Super glue. You can remove the sensor by giving it a sharp whack from the side with a dowel and hammer.

I have some really thin 2 sided tape. 2" wide. How much do you need? Email me your address and I'll send you a piece. My email is in my profile.

E600 or something like it.

I believe the part being attached to the crank is a magnet and the part on the frame is a reed switch. Would a thinner magnet fit? Or file down the plastic housing.

3M Transfer tape - it is an extremely thin (.05mm) very high bond double sided tape.

I do this all the time. Some epoxy. I use west system because I have it always around, but any of the quick set versions at the store will be fine.
You definitely don't want 5200. It has poor adhesion on aluminum that has not been prepped (which I wouldn't do to a crank) and bothers some plastics. It's likely a simple dab of silicon will do just as well if you clean the aluminum well.

quote:

Originally posted by MikeinNC:
Dab of 3M 5200 will work. It’s for marine industry, works when wet and has a littl flex .

But buying a whole tube would be too expensive.

Do you have any silicone caulking or the like? Try that.

3M 5200 if you NEVER want to remove it! Use 4200 if you want to remove it in the future.