Bicycle Mechanics - Fenders

I was looking at my bike i just got a Giant Sedona LX, and notice on the frame under neath the seat there are little threaded screw holes i was wondering what these where actually for, i think there for fenders but couldnt find any info in the manual or there website... I was wondering if anyone could give me a hand on this thanks... also how would i know what fenders to buy if this is what they are for? sorry for my noobness btu we all halft o start right...

Do you have a photo? Could be braze-on mounts for fenders, for brakes, or for racks.

The rear triangle of the frame is made up of the seat tube, the chain stay and the seat stay. If the threaded holes are near the top of the triangle on the seat stays (they slope down from the seat post to the rear hub), they're for a rear rack.

The fenders I've used are attached at threaded holes near the rear hub and a single threaded hole at the back of the bottom bracket tube (where the crank arms are attached).

Here, man had to dust off the old didgital rebel and 550ex man i cant wait till its nice out again... well anyays here is the picture

http://www.photochaos.com/pics/screws1.jpg

thos are jsut plastic caps over them...

Side ones are for rack, top one is for fender.

intresting, the guy at the shop said i couldnt havea rack on this bike cause it has disc breaks... he said i could get a seat post one but that carrys half the weight.. so what type of fenders are good to get?

They are Rack bosses. Fenders use them sometimes but they are primarily for racks. The majority of mtb fenders now mount to the seatpost or seat in some fashion instead.
The idea that a rack is not compatible with discs is ludicrous. I have done so for years on my Sedona. It merely requires a spacer on the caliper side, depending on the rack itself. Mount the rack as you would and check the caliper. If the rack strut is against the caliper, space it out so that it doesn't touch. Not a big deal at all.

P.S. Here is a pic of mine now that I have her raceworthy again.

Lol thats funny cause i was just thinking that... im a pipefitter and work around machinest also i was like uhh some old tent pole and a longer screw will do the tirck... lol i jsut havent seen a rack that actually bolts to the upper part of the frame.... am i mising somthing here... Kinda broke thow so no big hurry after bike,helemt, tier pump, lock, turnk rack. im kina broke.... yea that looks cool im gonan try to find some finders that screw in that i can put under the rack... those are cool fender thow....

also how would i know what fenders to buy if this is what they are for?

I pretty much start with the assumption that any fenders are going to require some kind of modification or bracket fabrication to fit onto any bike. I'm sure there are exceptions, but that's one of those Murphy's law things that's right much more often than it's wrong.

When buying fenders, take a close look at every bike that you see that has fenders. Look closely at every mounting bracket and attachment point. If your bike looks similar, ask the owner what brand they are. Schedule a whole Saturday morning for installing them - all day if you drink beer while you work at it.

For the sheer simplicity of it, I like the SKS Shockboard seapost-mount fender for the rear and fork crown mounted front. They mount in literal seconds and quick release as easy. But unlike many quick releasing designs, they hold up to cross country trail races.

If you have threaded frame fittings and want a permanent fender then SKS chromoplastic are the best.
Integrating fenders and rack with disk brakes will be interesting. If there are 2 threaded holes use one for rack and one for fender but otherwise, they both go onto the same bolt. You usually put the rack strut next to the frame, then the fender strut, to reduce the leverage on the bolt from luggage weight. If you need to space out the lugage rack you can try using the fender as a spacer. The fender stays can be bent to avoid interference.

Yea when i get my next nto workign check ill probly get a rack and rear fender and spend a weekend fittign it all up...