Different bolts in pallet and tombstone, what to do ?

[Panza]

Used tombstones. The boltholes in the tombstones are for M16 bolts, which looks about right for a 500mm pallet. The only problem is that the pallets have 14mm T-slots, so M12 bolts is the max that will go in.
M12 looks kind of tiny for the tombstones, but there will be 8 bolts on each pallet, and the pallets are made like that so it must be ok .. ?
I have figured 3 ways to fix the problem. All of those end up with M12 bolts holding it all:
- Make sleeves for the tombstone and just use M12 bolts.
- Turn and retread the bottom of M16 bolts to M12.
- Make custom bolts with 16mm shank, taper and then M12 threads at the end.

 

[Booze Daily]

16mm shoulder bolts come with M12 thread

 

[???]

Make custom bolts with 16mm shank, taper and then M12 threads at the end.

Shoulder bolts, you may be lucky and find the correct length.

 

[Orange Vise]

M12 is fine for a 500mm machine.

We have 400mm, 500mm, and 630mm machines from DMG Mori and every pallet on every machine is tapped for 1/2"-13.

Just make sure you use thick washers if your tombstone flanges are drilled for M16.

 

[Garwood]

I mounted my 400mm tombstones with 10 1/2" bolts.

I'd use thick hard washers under the bolt heads.

On a related note, my used stones looked unused, but the mounting faces looked milled with a Chainsaw. I was surprised. I setup and recut the bottoms flat and perfectly perpendicular to the faces. So I guess check the mating surfaces closely.

 

[Panza]

Thanks everyone! if I don't find should screws easily around here I'll just make sleeves with a thick top and use straigth M12 bolts.