How To Adjust Zero Bevel on the Bosch GCM 12 GDL

hello and welcome to this informal tip

video on the bosch professional glide

sorts of 12-inch gliding Mitas all with

a patented axial glide mechanism on the

back and what we're going to show you in

this short video is just to how how to

check the alignment of the blade at zero

bevel so what we've done with this

particular machine is deliberately miss

adjusted it we've got a a square resting

on the aluminium base very important to

have the square on the aluminium and not

resting on the plastic here which could

cause an error in the measurement and

you can see as we go up there there's a

massive gap there between the blade and

the and the back of the gauge there at

the back of the square so we're going to

correct this

there is a procedure outlined in the

manual which is fairly straightforward

the first thing you have to do is to

release the the front locking lever here

of course if you've got that lock down

we have this forward locking lever that

needs to be released and then as per the

instructions we go around the back of

the machine

and we have a couple of locking bolts

there a 10 millimeter bolt they're


I think 68 yet so there's two of them

there so just use a socket or a drill

driver there on it to loosen those off

okay and then the next thing we need to

do before any adjustment can be made

it's the loosen off grub screw it's I

think it's a four mil allen screw we

marked on the machine here number 70

because that correlates with what's in

the manual so we loosen off number 70 by

by three turns and then we're ready to

go now it's very important to note that

the top screw number 69 that's the one

that the head of the saw is resting on

that's if you like your reference screw

so when you tighten that it will correct

the error we put on this saw in the

correct direction so it will actually

move the head of the saw to your right

or to your left as you can see it as

we're viewing it in the movie so

tightening that top screw there will

actually bring the head up right and

hopefully it will get the saw perfectly

at zero so that it's touching the the

gauge of the square firmly so got a nice

flush fit there the cameras picking that

up it's also important to notice that

the the gauge there that the square is

is is kissing the the core of the blade

and to make sure that you've got that

between teeth at the bottom there don't

have it resting on a tooth make sure

you're going in to a gap between the

teeth otherwise again your adjustment

your reading might be affected the other

thing of course is that because that's a

set screw because that's a stop

effectively on the back that top allen

screw you do need to physically push the

head of the saw over to your left as

you're looking at it and then bring it

back again firmly on to the stop and

double-check that the alignment is still


also if the error is to the left as we

look at it in the video and you need to

correct it to the right it's very

important to note that that top screw

will not move the head to your right

okay it'll create space for that

movement but you do need to push the

head of the machine in the direction of

that stop so I'm hoping that's not too

confusing to see as you can see now

we've got a nice flush fit there between

the square and the blade and so we can

now lock this down so I think it's some

front locking lever down okay to

stabilize the whole thing and then we

just basically reverse what we did to

start with so we tighten number 70 at

the bottom there okay so that's the

lower grub screw the allen screw okay

just tighten that up not too much and

then finally to make it all stable with


m10 bolts and and that should do it but

please remember that top screw only

moves the head to the left if you want

to make a correction to the right if

that's where your error is then you do

need to loosen that top screw and push

physically on the side of the machine

the head against the stop so hope you

hope you find that useful it's a very as

I say informal movie but it's a fairly

straightforward procedure thanks for