Old power tool issue, fixable?

azk404 · Post by **azk404** » Mon Apr 13, 2020 10:47 am

HI there,

I acquired some old power tools for free but I have an issue with a Bosch GKS 65 circular saw. It starts up but sounds very loud and clunky, as though things that should be are grinding together slightly. The blade spins and I can start to cut through some reasonably soft wood but eventually it will jam and the blade will no longer spin even though the motor sounds like it's still running. If I pull back a bit the blade will start to run up again but the same thing will happen.

Basically it just doesn't have enough cutting power to cut through anything as the blade jams up even though the blade looks quite new.

Would be keen to take it apart to see if it's fixable but any advice would be good thanks.

A

big-all · Post by **big-all** » Mon Apr 13, 2020 10:58 am

may be the reduction gear has gone assuming the blade is tight

ayjay · Post by **ayjay** » Mon Apr 13, 2020 10:59 am

Have you checked that the nut/screw/whatever that holds the blade is done up tight? Does it have the correct bushing at the centre, (if necessary)?

azk404 · Post by **azk404** » Mon Apr 13, 2020 12:35 pm

Sorry bit of a disclaimer but I don't know what some of those bits are exactly but I will do some searching to figure it out. Blade was tight though.

I have take it off and removed a couple other bits. Powered it up and the part 846 in the image below which spins everything doesn't have much power so when its at full power I can stop the bit spinning with my fingers. No blade on it obviously.

fin · Post by **fin** » Mon Apr 13, 2020 12:48 pm

sounds like theres some damage inside the gearbox to me. usually there is a gear wheel on the end of the motor shaft that would drive number 45 gear wheel which in turn would drive the shaft that the blade is attached to. if it was number 45 that was damaged then it would be an easy repair. if it was the one on th end of the motor shaft then a lot more difficult.

it should be simple enough to take that part of the saw to pieces to take a look. may aswell as to replace a circular saw that size would be in the region of £100 i would imagine atleast.

im going of when i had to strip down my hitachi circular saw btw but i assume all circular saws will be pretty much the same.

fin · Post by **fin** » Mon Apr 13, 2020 12:49 pm

bet the previous owner has hit something very hard when hes been cutting up a floor. like an rsj for example or some brick work.

fin · Post by **fin** » Mon Apr 13, 2020 12:51 pm

id have thought taking the saw blade housing apart and then the lower guard offf will let you get acces to that small gear box to investigate. it couldnt really be anything other than that if the blade is fitted correctly

dewaltdisney · Post by **dewaltdisney** » Mon Apr 13, 2020 12:58 pm

Is not 45 plastic or nylon for that reason, so it strips the cogs if you hit something so hard it jams up in order to prevent damage to the other gears?

DWD

azk404 · Post by **azk404** » Mon Apr 13, 2020 2:01 pm

So I don't thing its the 45 piece that's the issue as that seems to be metal and that's the gear that is driven by the motor section.

I split the saw up to look at the motor section and the main bit, which I think is 3/50 piece, in the image below is what should drive 45. I ran the motor while it was disconnected and it spun fine so I am guessing 3/50 (or the bit in the photo at least) isn't connecting with 45 correctly. Is there supposed to be something on 3/50 which completes the connections? Is this the possible plastic/nylon bit dewaltdisney mentioned?

fin · Post by **fin** » Mon Apr 13, 2020 2:48 pm

whatever that part is in the picture looks well goosed to me. like its totally worn away

fin · Post by **fin** » Mon Apr 13, 2020 2:50 pm

so that would likely be the end of the armature. not owa clever. try putting the model number of the machine into ebay see if you can get an armature though youd need to get the correct either 240 or 110v

fin · Post by **fin** » Mon Apr 13, 2020 2:52 pm

defo reakon that saw has hit something hard thats stopped the blade dead when the motor has been under power

azk404 · Post by **azk404** » Mon Apr 13, 2020 4:49 pm

Thanks for the advice btw.

I think I have located a 110V armature on eBay for 15 quid so I wouldn't mind giving it a go.

Just looking at how to get access to the broken one though as I am not sure which way I am meant to go to remove the broken one.

Do I remove the bit the red arrow is pointing to some how and then what?

Or do I go the other way with the green arrow?

Is the thing my finger is pointing at the same bit or an extension of something else?

https://www.ebay.co.uk/itm/Bosch-GKS-19 ... Swsddekv4x

Someone-Else · Post by **Someone-Else** » Mon Apr 13, 2020 6:17 pm

azk404 wrote: ↑Mon Apr 13, 2020 4:49 pmI think I have located a 110V armature on eBay for 15 quid so I wouldn't mind giving it a go.

But your saw has a black lead, so its 240V?
A 110v armature will spin very very fast in a 240v saw

fin · Post by **fin** » Mon Apr 13, 2020 6:31 pm

all my 110v tools have black leads from the factory across makita, dewalt, elu, bosch, festool

normally to get armatures out youd have to take the carbon brushes out that press onto the commutator which is part of the armature. its all one assembly so will come out of either the front or the back but most likely the front where its damaged.