Securing a bench to slabs

[Alie Barnes]

Ok so im now thinking of buying a metal lathe bench, the downside is that my sheds base is of slabs and i have no option for concrete i have very hefty slabs 2ft square.
How do i go about securing a bench to these slabs? can they be drilled without breaking and what sort of fixings would i need?

Thanks for all help.

Alie

 

[cornucopia]

yes they can be drilled- i dont know the correct name but i call them expanding coach bolts- most builders/big sheds stock them- there a normal bolt with an expanding raw plug type end on them.

 

[boysie39]

Rawl bolts we call them
REgards Boysie

 

[big soft moose]

that said i'd be concerned about the vibration causing the slab to crack. In your place i would lift one of the slabs and dig a hole a couple of foot deep - fill that with concrete and hard core and embed a couple of bits of threaded rod - then use these to anchor the lathe.

 

[PowerTool]

Pete's suggestion of a concrete pad is probably the ideal - however,if not practical,I have drilled slabs and used anchor bolts succesfully before ; just plan where you are putting everything to get them all as near the centre of the slabs as you can.

Andrew

 

[cornucopia]

my vb36 is bolted down into modern 2'x2' slabs- i'm amazed as they are then glued to the concrete floor :shock: no problems

these are the bolts i use

 

[big soft moose]

my vb36 is bolted down into modern 2'x2' slabs- i'm amazed as they are then glued to the concrete floor :shock: no problems

these are the bolts i use

I would guess that the VB36 has so much mass itself that the vibration may be less of a problem than it is for lesser lathes.

one key thing is not to be talked into putting rubber between the lathe and the floor - there are some ill educated article on the internet that encourage this citing car engine mounts as precedent - but car engine mounts are designed to stop the engine vibration being transmitted to the body - they do not stop the engine from vibrating.

therefore putting a layer of rubber under your lathe will not make things better and may well make them worse by introducing bounce as well as wobble.

 

[cornucopia]

it has got allot of mass but its mainly at the top as the bottom is a box which holds all the electrics so the majority of the 300 ish kg is at the top - so the bolts /glue really do a good job- the other thing is the footprint of the vb is only 22" square so when you have a big out of balance piece hanging of one side the bolts are working hard.

 

[big soft moose]

Ok so im now thinking of buying a metal lathe bench, the downside is that my sheds base is of slabs and i have no option for concrete i have very hefty slabs 2ft square.
How do i go about securing a bench to these slabs? can they be drilled without breaking and what sort of fixings would i need?

Thanks for all help.

Alie

going back to alies dilema the other posibility would be to forget bolting it down but instead make a wooden cabinet arround the metal bench which can be filled with concrete blocks or bags of sand - that dramatically increases the mass and counteract vibration as much as bolting it to the floor.

there is a design for this in keith rowleys foundation in wood turning tho you need to adapt it to the shape of your lathe bench.

 

[wizer]

If you can afford a bit of extra height, I'd be inclined to double up the slabs and glue them together with grip fill.

 

[loz]

I'm not sure Alie has a problem ?

Has he mentioned vibration ? or being led to believe its a MUST to secure lathe to floor ?

My bench isn't and i dont have any vibration issues, i however only turn balanced stock, ( or i have slow speed till tru ) and balanced shapes, like bowls\ boxes or spindle objects.

It would be a different case if i was hanging planks off the outboard ( if i had one ) like some of the wonderful wall hangings i have seen by members in here.

( or i had the motor and torque to do so ..... one day. 8) )

Maybe there are other facters at play for the assumed vibration, ? Dirty unseated tapers, untrue bed ?, the current bench is not true, or only has three legs on the ground like a bad pub table ?

Loose headstock, tailstock, belt, Worn out bearing ?

Alie, can you explain your want for securing, do you have vibration issues and have ruled out all other factors ?

Does your lathe wobble when off ? have a tug at it and its componants and let us know

Or are you indeed spinning planks of an outboard, or swiveled headstock ?




Best Regards

Loz

 

[wizer]

good point Loz. Mine is just sitting on the concrete.

 

[Bodrighy]

Mine is on the wooden floor of a small shed, hardly solid. Yes I get vibration with off centre stuff but nothing that can't be handled easily. If I was doing the sort odf thing that George does maybe it would be different but for most of us as long as the lathe uitself is tied down securely to th stand / base it should be OK. Mine is on a Perform stand that I have feinforced by bolting chipboard flooring to to make it into a box and I have loads of wet wood stored in it drying out.

Pete

 

[Alie Barnes]

Alie, can you explain your want for securing, do you have vibration issues and have ruled out all other factors ?

Does your lathe wobble when off ? have a tug at it and its componants and let us know

Or are you indeed spinning planks of an outboard, or swiveled headstock ?

Ok this goes back to my shed post a few weeks ago and i can link if people need reminding. anyways i built my prefab shed and i was worried about vibration through the bench and causing wobble in my turnings.

So what i did was to lay 2 sheets of 18mm ply on the floor of the shed and screwed them together. i then placed my bench on this built a shelf on the bottom of the bench and packed it full of bags of sand.

i then put some triangulation onto the corners and across the ends. ( i should have just taken a picture) ive turned near round pieces of wood and with a cup of tea on the lathe dont seem to get much vibration.

But something with the lathe just still isnt right and im not sure what. i just cant quite get a true round piece of wood (i havent turned too much) recently since doing all this but when i do it seems to take a lot of wood to get a near true round. Like when you place a pencil on the wood and it colours in 2/3rds of the wood??????

it could be my technique i dont know ( i dont really have one) anyways so im gonna give it some more time, a little more ply (maybe) and level the lathe on the bench end to end as its currelty slightly out.

The main reason for this post is that im thinking of buying a metal lathe bench, putting in some shelfs and placing sand or concrete bags on the shelf to secure it then cut through shed floor and bolting it to the slab base.

Concrete is not an option (its a long and complicated story) but its not an option. its very frustrating.

Somewhat of a long post and apologies for that.

 

[big soft moose]

But something with the lathe just still isnt right and im not sure what. i just cant quite get a true round piece of wood (i havent turned too much) recently since doing all this but when i do it seems to take a lot of wood to get a near true round. Like when you place a pencil on the wood and it colours in 2/3rds of the wood??????

.

if you cant get a full round with that much weight attached to the lathe then i very much doubt that vibration is the problem - and thus neither a metal bench or bolting it down is going to help.

I would suspect that if its not your technique then your headstock isnt running true and or the centres or face plate arent sitting square to the drive.

what you really need is an experienced turner to come an take a look - i would offer but i'm not going to be in m/head for about a month - but there must be someone on here who lives closer.

 

[Alie Barnes]

But something with the lathe just still isnt right and im not sure what. i just cant quite get a true round piece of wood (i havent turned too much) recently since doing all this but when i do it seems to take a lot of wood to get a near true round. Like when you place a pencil on the wood and it colours in 2/3rds of the wood??????

.

if you cant get a full round with that much weight attached to the lathe then i very much doubt that vibration is the problem - and thus neither a metal bench or bolting it down is going to help.

I would suspect that if its not your technique then your headstock isnt running true and or the centres or face plate arent sitting square to the drive.

what you really need is an experienced turner to come an take a look - i would offer but i'm not going to be in m/head for about a month - but there must be someone on here who lives closer.

Well if you are ever in the area i would be very pleased if you could take a look because at the moment i dont really know where to go from now and i dont want to do anything drastic unless i know for sure that it/isnt vibration.

 

[loz]

Alie,

Will you kiss test your centres just to check they are aligned.

I loosen my headstock, and remove the drive centre, then bring the tail right up so the tail centre enters the spindle, then tighten my headstock, this way i knwo they are true.

Or a simple kiss test - leave centers in, and bring the tail up, see if the points touch.

revolve them both see they stay true ( centres not bent )

 

[Jenx]

Hi Alie ... by the sounds, the problem is at the headstock end, so even the 'kiss test' may not solve too much...

Without trawling back over everything .. what are you 'chucking' with ?
Is it just a screwed faceplate ? is it a faceplate that mounts in the chuck jaws ? ...


It sounds very much as though somethings a little out of kilter at the headstock end of things ... have you been in there and had a good look ? .. are there grub-screws on the headstock shaft securing pulley(s) to the shaft, that have come a bit loose ? ( usually Allen-socket type grubbers )...

Can you hold a large-ish piece mounted and try to feel lateral ( axial-float ) movement in the shaft.. ( bit of a 'grunt' operation, but similar to how you feel for 'play' in the wheelbearings on your car.. )...?

It may be 'obvious'.. but the more 'joints' between the headstock and the workpiece, the more 'scope' there is for 'weirdness' to take place .. eg : - The nose may come out the headstock and be threaded, then its possible to have a chuck insert, then the chuck, then a face plate ring, then the workpiece itself .. you follow where I'm headed ? ... lots of 'joints' which each potentially present a problem, if not functioning totally 100% accurate.

Assuming you are cabable of 'facing up' a blank, perpendicular to the lathe-bed .. then find the application of pencil is only hitting 2/3'rd of that 'trued face' ... then something is indeed a tad out.

I'm not hugely experienced turner.. but have a lifetime of repair / maintenance of similarly configured machinery.. as do a large amount of the 'bods' here, so between us all, we should be able to get to the bottom of the issue...
I'd be inclined to start right back at the 'beginning of the drivetrain' ...
we can assume your motor and motor-side pulleys are ok ( check the grubscrews on the motor-side pullys & the belt condition & alignment anyway, as a matter of good housekeeping, -- then really get into the ribs of what is occurring from the headstock drive belt / pulley arrangement, forwards.

It has a 'familiar' taint of "Headstock bearings shot" feel to it ... but without 'proving' a fault.. its easy to get caught up in throwing replacement components at a fault, and not end up curing the problem.
As mentioned... take consideration of the number of 'interfaces' between the spindle and the workpiece.. there's a lot of scope for 'indescrepancies' there, and the more 'jointing' there is.. the more this scope widens.

Start back at the beginning of the drive, and work forwards, checking and tightening etc...

At the end of the day, there's not that many components that can be causing the problem... and it may be an easy enough 'fix' once you get right into the 'puddins' of the machine.

HTH 8)