A question about fastening in lightweight concrete with anchor compound.
To achieve the highest possible pull-out value, I have seen recommendations to make a conical hole.
Can this be done with a regular drill?
Or do you need a special tool, such as Fischer's conical drill PBB, which is found almost at the bottom here http://admin.getanewsletter.com/t/pm/59464213944/ ?
To achieve the highest possible pull-out value, I have seen recommendations to make a conical hole.
Can this be done with a regular drill?
Or do you need a special tool, such as Fischer's conical drill PBB, which is found almost at the bottom here http://admin.getanewsletter.com/t/pm/59464213944/ ?
The cone should have its largest diameter inside the hole, and it's not quite easy with your suggestion because it usually ends up largest outside the hole instead.Oldboy said:
But it's doubtful if such solutions are necessary for normal conditions, as even without a straight hole, it provides great strength.
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ESSVE's lightweight concrete plug "with wings" at 8mm provides incredibly good grip even though the plug itself is not actually that long. There is also a 10mm version but I've rarely felt the need to use it since the 8mm provides very good grip. Tested everything from sparring rails to wall cabinets in porous lightweight concrete.
Never in my professional life have I encountered conical holes in ltb to improve strength; the practice, in my opinion, is through bolts if something heavy needs to be attached.
Otherwise, it holds like a rock with anchor mass!
How does one make these conical holes? It would be interesting to know in case I ever need to do it.
Otherwise, it holds like a rock with anchor mass!
How does one make these conical holes? It would be interesting to know in case I ever need to do it.
It usually involves multi-family houses or premises for offices or industryMathiasS said:
Yes, it concerns load-bearing details, such as brackets for supports.
But when do you need to chemical anchor a bolt for something in a regular house? It's not like you're fastening the flat TV with two chemical anchored M12s 😁
Oceanis wrote:
"The cone should have its largest diameter inside the hole and it's not easy with your suggestion because it usually becomes largest outside the hole instead."
You hold the drill still at the entrance and ream out the hole internally. It's incredibly easy in lightweight concrete. If you find it difficult, you can take a piece of wood or metal sheet with a hole (matching the drill diameter) to "ensure" the drill doesn't over-ream at the surface.
"The cone should have its largest diameter inside the hole and it's not easy with your suggestion because it usually becomes largest outside the hole instead."
You hold the drill still at the entrance and ream out the hole internally. It's incredibly easy in lightweight concrete. If you find it difficult, you can take a piece of wood or metal sheet with a hole (matching the drill diameter) to "ensure" the drill doesn't over-ream at the surface.