another tower install question

[riverfreak]

putting on the tower Sat., ? is when we drill the holes (there are 4 for each mount) should we use the same size bit as the bolt or slightly larger? Maybe a stupid question but we've had some debate over a tight fitting bolt and the gel coat? I'll try to get some pics, but the eyeful tower is impressive, very smooth weld and fitting unlike some popular towers I've seen, and the racks too, very well built, had it cutom painted mettallic silver......

[OttoNP]

I was wondering how the metallic silver color would come out...

Drill a hole that is slightly larger. In a joint like that you are using the bolts to clamp the mount and the backing plate to the fiberglass. Ideally all the forces will be transferred to your boat through the plates clamping and not through the bolts, they should just pull the plates together. This is because the bolts have much less contact area than the plates. When you have the mounts on the bolts should move freely in and out of the holes but not wobble too much side to side.

These are the steps I would take:

1. Determine the final size drill bit you'll use, you can test it by drilling holes in wood or better yet fiberglass, with wood you have to make sure you've cleared out all the saw dust, etc... You want a size so that the screw threads don't catch on the hole but that is also not too loose.

2. After you have all the holes marked, start will a very small drill bit, it is much easy to drill a precise hole with a small bit.

3. Continue to drill larger holes and when you get to the final size, start the hole by running the bit backwards, it may help in getting a neater hole.

4. After you drive the large hole, you may wish to chamfer the hole by using a larger bit and running backwards to take of the sharp edge. You don't want to make it too large because you are removing surface area that the plate could be in contact with.

5. Repeat for each hole, it is a good idea to place the mount on the hole to make sure everything lines up right before drilling each new hole.

Good Luck,
Nick
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AIRSOFT SMOKE GRENADE

[OttoNP]

Here's a more definitive answer, make the holes the same size as the ones in the mounts.

Also, suspending the tower over the boat made the installation so easy, I highly recommend it. You can do this by installing it in your garage or under a tree, or you could even build something to hold the tower up. You might be able to get people to hold the tower in place will you mark the holes. Also, if the mounts aren't too much on the sides, the tower may stay in place on its own.

Nick
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MARIJUANA INDICA

[1LD]

may want to countersink holes also. this will spread gelcoat away from screws so they don't stress gel & less likely to create gel cracks from screw contact. good luck

[Fishmaster]

Remember to run the drill in reverse until you are through the gelcoat or the gelcoat could chip.

Someone had posted a great idea as well which was to sand where the chamfer meets the gelcoat to creat a small radius. Removing any sharp edges can only help.

Bill