Drilling in a concrete pillar...

[canardo]

I am living in a 30 year old bungalow (1 story free standing house) and I want to hang a hammock in the garden between a tree and a pillar of my outer wall. The pillar is about 18 cm wide. I have a metal plate being made 15x15 cm and a solid hook welded on it I want to screw with 4 8mm metal dowels which are 7 cm long...

Questions:

Can I drill 4 10mm holes about 7 cm deep into a pillar or i this a bad idea?

And, what kind of drilling machine I would need, I have a BOSCH drill hammer but not a professional heavy duty thing?

Thanks for your help in advance...

[Crossy]

Probably no issue whatever.

One of those anchors would likely do the job.

[manfredtillmann]

suggest you abandon the plate. welded joints are subject to fatique cracks with moving attachments. if you can, drill straight through the pillar to the other side, use an eyebolt or similar, washer and nut on outside, secure the bolt from movement by using epoxy resin. similar on the tree section, do not rely on threaded hooks in life wood. if your hamocks fails the most likely injury you or someone will sustain is spinal.

Edited September 27, 2015 by manfredtillmann

[canardo]

suggest you abandon the plate. welded joints are subject to fatique cracks with moving attachments. if you can, drill straight through the pillar to the other side, use an eyebolt or similar, washer and nut on outside, secure the bolt from movement by using epoxy resin. similar on the tree section, do not rely on threaded hooks in life wood. if your hamocks fails the most likely injury you or someone will sustain is spinal.

Unfortunately I cannot drill through the entire pillar, but thx for the advise with the welded crack potential, will check if I find a different dowel with a hook or "O" thingy at the end...

[stoneyboy]

Why not just use a fan belt like most Thais do,no need for drilling or any thing.

[bankruatsteve]

Or, you could put your plate on the opposite side of the lateral tension and you only have to worry about the post.

[eyecatcher]

I agree should not be a problem at all.

I am holding up the roof of my house with three of these on a 5 inch square plate. They cost 3bt each 50mm long and only need an 8mm drill.

I went from 4 to 3 as they can carry a tank.

At least you have the best drill! .....it reminded me that i should go and buy that mercedes coupe even though i know nothing about cars.

As for the hook failing...possible yes so just make sure you dont set it up 4m above your concrete drive.

[IMHO]

The problem I foresee is it's a 15cm2 plate on an 18cm wide post - assuming the 4 bolts are going on each corner of the plate, they're going to be awfully close, or clash, with the rebar inside the post. The normal standard for rebar spacing is 15-35mm from the outside edge.

Even if you manage to drill a hole that avoids the rebar, you could still be giving the rebar a way to corrode.

If it were me, I'd probably secure the plate using just 2 bolts, in the center-top / center-bottom where I have the most chance of avoiding rebar.

[canardo]

Why not just use a fan belt like most Thais do,no need for drilling or any thing.

Because it is a pillar of the house attached by walls and beams...

Edited September 27, 2015 by canardo

[Soutpeel]

Masonary drill bit and rawl bolts not quite sure what you mean by dowls, if your really paranoid about the integrity of the rawl bolts pack the holes with epoxy glue before you tighten the rawl bolts

[Soutpeel]

suggest you abandon the plate. welded joints are subject to fatique cracks with moving attachments. if you can, drill straight through the pillar to the other side, use an eyebolt or similar, washer and nut on outside, secure the bolt from movement by using epoxy resin. similar on the tree section, do not rely on threaded hooks in life wood. if your hamocks fails the most likely injury you or someone will sustain is spinal.

Welded joints done properly in carbon steel will not be subject to fatigue cracking under these conditions

[manfredtillmann]

suggest you abandon the plate. welded joints are subject to fatique cracks with moving attachments. if you can, drill straight through the pillar to the other side, use an eyebolt or similar, washer and nut on outside, secure the bolt from movement by using epoxy resin. similar on the tree section, do not rely on threaded hooks in life wood. if your hamocks fails the most likely injury you or someone will sustain is spinal.

Welded joints done properly in carbon steel will not be subject to fatigue cracking under these conditions

i would perhaps agree with you - if we were not in THAILAND

[Soutpeel]

suggest you abandon the plate. welded joints are subject to fatique cracks with moving attachments. if you can, drill straight through the pillar to the other side, use an eyebolt or similar, washer and nut on outside, secure the bolt from movement by using epoxy resin. similar on the tree section, do not rely on threaded hooks in life wood. if your hamocks fails the most likely injury you or someone will sustain is spinal.

Welded joints done properly in carbon steel will not be subject to fatigue cracking under these conditions

i would perhaps agree with you - if we were not in THAILAND

Not if you get a proper welder to do it not a frence wire burner your most likely referring to who are not welders in the first place and before you start with a diatribe, let me just clarify....

i work in Engineering in Thailand and have over 120 real Thai welders working for me and they are as good as, if not better than some farangistan welders i have come across over the years

[manfredtillmann]

suggest you abandon the plate. welded joints are subject to fatique cracks with moving attachments. if you can, drill straight through the pillar to the other side, use an eyebolt or similar, washer and nut on outside, secure the bolt from movement by using epoxy resin. similar on the tree section, do not rely on threaded hooks in life wood. if your hamocks fails the most likely injury you or someone will sustain is spinal.

Welded joints done properly in carbon steel will not be subject to fatigue cracking under these conditions

i would perhaps agree with you - if we were not in THAILAND

Not if you get a proper welder to do it not a frence wire burner your most likely referring to who are not welders in the first place and before you start with a diatribe, let me just clarify....

i work in Engineering in Thailand and have over 120 real Thai welders working for me and they are as good as, if not better than some farangistan welders i have come across over the years

sorry, i did not mean to step on your - or anyone else's - toes. i simply have not seen anything of the kind of quality work that either you or anyone of your 120 good welders could produce. i do not even walk over a welded drain grate up here in the north east. cheers.

[wayned]

The biggest problem that you will have drilling the holes is if you hit steel re-bar in the concrete. You can't drill through it and it will destroy your masonry bit if you try. Murphy's law says that you will hit it at least once drilling four holes with predetermined spacing!

[Soutpeel]

suggest you abandon the plate. welded joints are subject to fatique cracks with moving attachments. if you can, drill straight through the pillar to the other side, use an eyebolt or similar, washer and nut on outside, secure the bolt from movement by using epoxy resin. similar on the tree section, do not rely on threaded hooks in life wood. if your hamocks fails the most likely injury you or someone will sustain is spinal.

Welded joints done properly in carbon steel will not be subject to fatigue cracking under these conditions

i would perhaps agree with you - if we were not in THAILAND

Not if you get a proper welder to do it not a frence wire burner your most likely referring to who are not welders in the first place and before you start with a diatribe, let me just clarify....

i work in Engineering in Thailand and have over 120 real Thai welders working for me and they are as good as, if not better than some farangistan welders i have come across over the years

sorry, i did not mean to step on your - or anyone else's - toes. i simply have not seen anything of the kind of quality work that either you or anyone of your 120 good welders could produce. i do not even walk over a welded drain grate up here in the north east. cheers.

You wont see it eithet in the likes of Nakon Nowhere and typically drain covers are castings as opposed to welded anyway ...fact is there are some excellent Thai welders out there and many work over seas as well...

[eyecatcher]

As I read the thread, the engineering design of something that really probably only needs 2 screws seems to be getting a bit hypherluted.

as a bit of humour I was going to post a pikky of a fat man in a banana hammock saying none of us know how heavy the OP is;

However I had a big shock, and learned something when I googled "fat man in a banana hammock"

you are forewarned!

[manfredtillmann]

suggest you abandon the plate. welded joints are subject to fatique cracks with moving attachments. if you can, drill straight through the pillar to the other side, use an eyebolt or similar, washer and nut on outside, secure the bolt from movement by using epoxy resin. similar on the tree section, do not rely on threaded hooks in life wood. if your hamocks fails the most likely injury you or someone will sustain is spinal.

Welded joints done properly in carbon steel will not be subject to fatigue cracking under these conditions

i would perhaps agree with you - if we were not in THAILAND

Not if you get a proper welder to do it not a frence wire burner your most likely referring to who are not welders in the first place and before you start with a diatribe, let me just clarify....

i work in Engineering in Thailand and have over 120 real Thai welders working for me and they are as good as, if not better than some farangistan welders i have come across over the years

sorry, i did not mean to step on your - or anyone else's - toes. i simply have not seen anything of the kind of quality work that either you or anyone of your 120 good welders could produce. i do not even walk over a welded drain grate up here in the north east. cheers.

You wont see it eithet in the likes of Nakon Nowhere and typically drain covers are castings as opposed to welded anyway ...fact is there are some excellent Thai welders out there and many work over seas as well...

no, i am afraid they are not cast (up here in Nakhon Nowhere) but made from scrap or what ever they have found to make do. i have personally observed a moped 'fall' through one of those grates in a major street.

mate, i fully agree that there a lots of different standards - but you always engineer to the lowest available.

who knows where the op got his welding done? obviously not your shop.

there are a multitude of issues with his problem and the solution i posted eliminates most of them.

all good?