help with castor screws please

[Guest joshua]

hi,

basically i got two questions, so here goes the first one.

if i have 4 castors that say they can take 70kg each, does this mean that when i screw all 4 castors to the bottom of my cab, is the maximum total load still 70kg? Or do I add up all the castors, making a total maximum load of 280kg?

thanks and heres the second question:

i just bought some castors, but they did not come with any screws. these are the ones:

i need to attach them to a warwick 211 pro plywood cab. i cant open the cab up to thread bolts onto the screws, so the screws are just gonna have to stay in without bolts somehow. anyway here are the specs of the castors:

75mm Light Duty swivel Castor Grey Rubber Wheel Ref: PLM75GRT
Overall Height : 98mm
Wheel Size : 75mm
Wheel Type : Grey Rubber Plain Bearing
Load Rating : 70kg
Fixing Plate Size : 60 x 60mm
Bolting Centres : 48/38 x 48/38mm
Bolt Size : 6mm

can anyone point me in the right direction for some screws that will work good with them?

many thanks guys!

Edited November 14, 2008 by joshua

[Protium]

Some short self-tapping screws should do the trick. Try your local hardware store, and get ones with a flange head ()

[chris_b]

Take one of the speakers out and then you can use bolts.

[Guest joshua]

i cant it is a "sealed" cab, there are no screws or anything holding it together, i think its glue

[jerseytrev]

[quote name='joshua' post='329383' date='Nov 14 2008, 08:14 PM']hi,

basically i got two questions, so here goes the first one.

if i have 4 castors that say they can take 70kg each, does this mean that when i screw all 4 castors to the bottom of my cab, is the maximum total load still 70kg? Or do I add up all the castors, making a total maximum load of 280kg?

thanks and heres the second question:

i just bought some castors, but they did not come with any screws. these are the ones:

i need to attach them to a warwick 211 pro plywood cab. i cant open the cab up to thread bolts onto the screws, so the screws are just gonna have to stay in without bolts somehow. anyway here are the specs of the castors:

75mm Light Duty swivel Castor Grey Rubber Wheel Ref: PLM75GRT
Overall Height : 98mm
Wheel Size : 75mm
Wheel Type : Grey Rubber Plain Bearing
Load Rating : 70kg
Fixing Plate Size : 60 x 60mm
Bolting Centres : 48/38 x 48/38mm
Bolt Size : 6mm

can anyone point me in the right direction for some screws that will work good with them?

many thanks guys![/quote]


280kg as the load is spread over the four

[Merton]

[quote name='chris_b' post='329470' date='Nov 14 2008, 11:12 PM']Take one of the speakers out and then you can use bolts.[/quote]


[quote name='joshua' post='329484' date='Nov 14 2008, 11:38 PM']i cant it is a "sealed" cab, there are no screws or anything holding it together, i think its glue[/quote]
You can still unscrew the speaker grille and speakers and then there's be a nice big hold to get inside the cab!

[Dr.Dave]

If you do manage to get inside and use bolts be aware that the internal plywood walls may mean that you can't get the castors as close to the corner edges of the cab bottom as you'd think/like. That's because if the bolt heads are right up against the wood inside you can't get a spanner on them.

Siting them further away from the corners , towards the middle , can have the effect of allowing the cab to 'tip' easily.

It stands to reason that the further into the corners you can get the castors the more stable the cab will be - so for the above reasons - and against much of my better judgement in terms of 'using best available' I'd go for screws every time , esp with cabs having a small footprint.

[Merton]

[quote name='Dr.Dave' post='330462' date='Nov 17 2008, 10:04 AM']If you do manage to get inside and use bolts be aware that the internal plywood walls may mean that you can't get the castors as close to the corner edges of the cab bottom as you'd think/like. That's because if the bolt heads are right up against the wood inside you can't get a spanner on them.

Siting them further away from the corners , towards the middle , can have the effect of allowing the cab to 'tip' easily.

It stands to reason that the further into the corners you can get the castors the more stable the cab will be - so for the above reasons - and against much of my better judgement in terms of 'using best available' I'd go for screws every time , esp with cabs having a small footprint.[/quote]
What I did to alleviate that problem was use screws in the places you can't get a bolt, and use bolts everywhere else.

[Dr.Dave]

[quote name='Merton' post='330482' date='Nov 17 2008, 10:32 AM']What I did to alleviate that problem was use screws in the places you can't get a bolt, and use bolts everywhere else.[/quote]

Yep - that's the way.

[Guest joshua]

ok well ive attached all 4 castors, but because the cab is not very deep, if a bit of weight is applied to the front top of the cab, the whole cab falls forward - something i dont want to happen with another cab and an amp on top of it!
so, im thinking of unattching the front 2 castors and replacing them with 2 castors that have a built-in brake. do you think that will do the trick?

EDIT:

oh no i think ive got a far bigger problem now.
i was just playing through my rig and i noticed the speakers (or at least one of them) was crackling up a bit. then i remembered as i was drilling the holes for the screws, the drill bit kept getting caught up in the white wool that is inside the cab. i thought nothing of it, but now im starting to think i might have drilled into one of the speakers!
i sure hope not! lol

[Guest joshua]

ok well it seems it was the compressor on my zoom b2.1u that was overloading the tweeter on the cab and making it buzz. i dont know why it was doing that, as the clip light was not coming on, and it was only on volume #1. oh well, at least i know its not a broken speaker!

[Protium]

I'd have used screws anyway, that way you're not drilling right through the walls and potentially getting air leaks.

It'll also be easier to permanently remove the castors without the need to fill bolt holes to seal the cab again.

Too late by the sounds of it