Drilling in concrete - what am i doing wrong

[edl]

hi all - want to mount a winch in my concrete floor to be able to move the project car in and out of the garage - once out of the garage the driveway drops and so i need a winch to ensure it doesn't go too quickly and it would be the only way i could get it back in without 3 of my good buddies around

i am using "drop in" anchors (female thread on the inside).

the mounting bracket for the winch has 11 holes 4 on each end that are 3/8 to anchor the bracket and 3 in the middle that are 5/16 where the winch mounts (and these then go through the bracket and into the anchors to act as further anchorage

the problem i am having is I can't drill a hole exactly where i mark it - i start with a pilot bit and do a starter hole and work my way up and none of the 3 holes i have tried has ended up where I started

i am using a Milwaukee 28v hammer drill with a masonary bit - my guess (which can't be right) is that the hammering action walks the bit ever so slightly that after an a while the hole is off - but who knows...well ... hopefully YOU know ... how do i do this??? what am i doing wrong?? - thanks!! ed

 

[bmwpower]

hi all - want to mount a winch in my concrete floor to be able to move the project car in and out of the garage - once out of the garage the driveway drops and so i need a winch to ensure it doesn't go too quickly and it would be the only way i could get it back in without 3 of my good buddies around

i am using "drop in" anchors (female thread on the inside).

the mounting bracket for the winch has 11 holes 4 on each end that are 3/8 to anchor the bracket and 3 in the middle that are 5/16 where the winch mounts (and these then go through the bracket and into the anchors to act as further anchorage

the problem i am having is I can't drill a hole exactly where i mark it - i start with a pilot bit and do a starter hole and work my way up and none of the 3 holes i have tried has ended up where I started

i am using a Milwaukee 28v hammer drill with a masonary bit - my guess (which can't be right) is that the hammering action walks the bit ever so slightly that after an a while the hole is off - but who knows...well ... hopefully YOU know ... how do i do this??? what am i doing wrong?? - thanks!! ed

You need the winch mounting plate in place when you do the drilling - similar to what they did when they installed my lift. Drill through the holes in the mounting plate, into the floor.

 

[Yotaforce]

I agree, you need to drill THRU the holes in the bracket. Rock in the concrete will cause the hole to move while drilling.

 

[edl]

wow...simplicity really is profound!...ok, i'll give that a try...any other tips or tricks?? - one other thing may be the bit - it is from a HFT pack of bits - maybe I need to be using something higher end for this job?? - any suggestions? - thanks, ed

 

[Yotaforce]

I use a water bottle and keep the hole wet while drilling. It helps it go alot faster, keeps the bit cool, evacuates the dust out of the hole. It's nice to have a buddy pour the water while you are putting the force on the drill. I never had to use a hammer drill using this technique either, just a concrete bit (cheapies at that!).

 

[mhoffm911]

You can also use your air compressor to blow the dust out while drilling.

See also:

http://www.wikihow.com/Drill-Into-Concrete

 

[edl]

thx guys!````

 

[JCByrd24]

At those sizes I don't think you need a pilot hole either... plate in place, right size bit in holes, go for it. After the first couple you could even bolt the plate down to insure it doesn't move.

 

[kbs2244]

Use the shop vac to clean the holes.
It is a whole lot neater than blowing with the compressor.

 

[Wilbur]

You might want to anchor the winch some how with a frame tied to your studs or something so it doesn't move (not sure how heavy it is or if it would slide on the floor as you are drilling).

 

[MXtras]

Don't apply much more pressure than the weight of the drill. Let the hammer do it's job. And another recommendation for the shop vac instead of the compressed air.

Scott

 

[5wndwcpe]

Or, if the holes get to boogered up, drill them oversize and epoxy in some quality threaded rod and run nuts and washers down them. If you don't want the winch there at a later date, just cut the studs and grind the stubs flush with the floor.

 

[joa65]

I'd like to know more about this project. I have the same issue and had a similer solution in mind. I haven't yet followed through.
Have you picked a winch yet? How far do would have to pull the car at the max? 50~60 feet for me. Can a winch hold that much cable?
Let us know how this works out.
Thanks,
Jeff

 

[edl]

thanks all - very good suggestions

vac - yep...when i drilled the holes that ended up going off, i had the vac an inch or so awawy from the drill sucking everthing up

lubrication - i squirted wd40 in as i went - i guess i'll try water this time (i take from the above that water will be better)

studs - good idea if the holes go bad again - original problem was alignment of the hole - then i tried to "move the hole" that just gave me a really big how and that was useless - the elegant part of the drop in anchors (and this came from you guys in another thread) is that they are flush with the concrete floor - you bolt in the winch - when done, you unbolt, plug the anchors and there is nothing to trip over

winch - is here http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=91781

mounting plate - is here http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=93202

will keep you guys posted (sorry for the pun!) as to progress - thanks! ed

 

[Junkman]

I was the one that suggested the anchors, so I guess that it is up to me to bail you out on this project. If the holes are off, then drill them over-sized and use the epoxy concrete to hold them in. Just bolt the anchors to the winch, and put the epoxy into the holes. Then set the winch on the floor with the anchors bolted to it and the anchors going into the epoxy. Once everything sets, then you can take the winch off and take a picture of your work. As for the WD40..... save that for your car door hinges, and use water as the lubricant for drilling. If you want, you can epoxy one anchor in, then bolt the winch, and drill the rest of the holes through the winch mounting plate. The one epoxied anchor should hold it secure for drilling the rest of the holes.... Junk..

 

[partsman]

wow...simplicity really is profound!...ok, i'll give that a try...any other tips or tricks?? - one other thing may be the bit - it is from a HFT pack of bits - maybe I need to be using something higher end for this job?? - any suggestions? - thanks, ed

you are useing masonary bits right ???

 

[boiler7904]

you are useing masonary bits right ???

Says he is in the first post.

FYI - there is no such thing as masonary. It's masonry.

 

[partsman]

sorry teach my huked on phonex hasnt come yet

 

[DiStOrTiOn]

We drill into concrete at work all the time. Our preferred method is a hilti hammer drill that plugs into the wall, with the appropriate hilti bits. Putting those size holes in, you shouldn't need the pilots, but the bit will walk, and I agree with the above suggestions. Drilling concrete is as much an art as it is a science.

 

[edl]

thanks all

junk...to late (for now) on the expoxy - after all the bad holes figured i was useless (right, can't even drill a hole straight) and filled it all up with liquid concrete in a bottle - so need to grind that down flush and start over (moving a few inches so as not to hit the old anchors now buried (may they rip) in the concrete!), as you guys have bucked me up

if i mess it up again, i'll go the epoxy route (oh, and as long as it is pretty clear i am an amateur...when you say expoxy...is something like JB weld sufficient?)

thanks! ed

 

[5wndwcpe]

JB Weld is great stuff but you're gonna go through a whole lot of those little tubes. I'd use an epoxy made just for this application or what may be easier to find (Lowe's, HD etc.) is Hot Plug. This is a fast setting, high strength cement used to anchor iron handrails into concrete steps and whatnot.

 

[russlaferrera]

Sometimes when drilling you hit a stone and it stops the drilling progress. Hit it with a center punch to break it up then continue drilling.

 

[edl]

thx guys...

 

[Bigger Hammer]

I'm not sure if any of the posts made it very clear, but mark out your holes as you did the first time around and drill the first hole. This first hole doesn't matter if you are drilling through the winch plate or not. After you get one anchor in place, bolt the one anchor through the plate and tighten it down. After you have one in place then drill hole number two. Anchor it down tight and you should be in the clear to go ahead and drill all the rest of the holes at once. If you only have one anchor tightened down the drill can and will walk on you taking the plate with it. That is the reason to get two in and tight before going hog wild drilling.

Don't waste your time with any water or other type of lube. All the hammer drill really is is a delicate and precise jack hammer. It pulverizes the concrete and rocks as it drills. It's not a friction type cut like a core bit or a concrete saw blade.

 

[edl]

thanks - that is the intent - believe it or not, the water helped (or maybe not) - what i mean is that it allowed for an incredibly precise hole - the last time, with the first hole, which as you say it doesn't matter if it walked a little - the hole still ended up somewhat bigger than the bit and fairly rough - but using water, the hole was snug and smooth to right to the bit - the problem then became that the "drop in" anchor wouldn't drop in - maybe the drop in mfgr expected a somewhat bigger hole with the traditional "pulverize" method - my solution? - get a big hammer - pounded the thing good and hard - was not able to make it sink all the way (and yes, the hold was deep enough and the bit was the size the anchor mfgr states on the box to drill the hole with) - not wanting to give up this time, i used junk's suggestion to "make the hole bigger" and so undaunted, i took a metal bit to drill it out - well to make a long story short, i ended up with a 3x3 hole that still has some metal stuck at the bottom - frustrated as all get out, i filled the quarry up with liquid quickcrete and again decided to bag the whole thing - today being a new day...maybe someone can point out what i am still doing wrong - i understand the using the plate and getting the holes to line up (although i didn't get far enough to see it work...but it seems like that will be the ticket) - despite what big hammer says...i kind of like the result using water (NOTE...I did not get that result using oil...so water must react with the concrete a bit differently

- so now what? - bigger bit? - or just wiggle the bit as I drill to get a slightly bigger hole? - maybe these HFT bits are actually not the size they say?? - any other thoughts - i am determined to drill 11 concrete anchors...this will not beat me!

 

[the intimidator]

First off you don't need all eleven of those holes you would be just fine with 4, all the holes are there to give more flexibility in the mounting position on a atv or small car, trailer ect. I put a 2500 pound warn winch on a buddies car trailer 3 years ago with 4 bolt's and it is still hanging tight and that winch will pull a truck onto the trailer. Go out and get a good bit you will be amazed by how much better and faster they are. If the anchor does not quite fit rock the drill bit side to side in a circular motion and don't use too much pressure or you will fry the bit. hope that helps you out some good luck getting that done.

 

[Bigger Hammer]

Does HFT mean Harbor Freight? If so, I'd suggest dropping those bits and getting a Bosch bit. If your dsrill has a 1/2" chuck I'd suggest getting an SDS bit from Lowes. They are made for an SDS drill so they have a funky shank on them but they can be used in a 1/2" chuck just fine. The cheap junk bits will wear quickly and actually drill a smaller hole.

What brand of drop ins are you using? Ever drop in that I've ever used was a fairly tight fit. If you are using water you are creating concrete slurry inside the hole. With the wet slurry you won't be able to get the hole cleaned out properly and believe it or not, the wet dust will actually bind things up inside the hole. For beating them in I sometimes will thread a bolt down into the anchor and beat on the bolt head. That will allow you to beat the anchor in without setting it. I'm back to my original suggestion of drilling it dry. Vacuum the hole out and they should slip right in.

Your mid America location isn't the part of Mid-America that includes Indianapolis is it?

 

[edl]

thx bh - went HD and bought a hilti and a bosch 1/2" bit - so we'll see what difference that makes - will try w/o water this time as the hole will end up a bit biger and it was too small the last time - the anchors are these from graingers:

Item Details
Fasteners > Anchors > Drop-In Anchors

Anchor,Drop-In,Pk 50
Drop-In Anchor, Flange Type, Material Zinc Plated Steel, Anchor Dia 1/2 In, Thread Size 3/8-16, Thread Depth 1/2 In, Min Embedment 1 5/8 In, Ultimate Tension in 4000 PSI Concrete 3800 Lb, Ultimate Shear in 4000 PSI Concrete 3160 Lb, Drive Tools 3A498, Meets/Exceeds GSA Specifications FF-S-325, Group VIII, Type 1, Package 50 Grainger Item # 3A493
Your Price (pk.) $22.17
Package Qty. 50
Brand RED HEAD
Mfr. Model # RM-38
Ship Qty. 1
Sell Qty. (Will-Call) 1
Ship Weight (lbs.) 3.2
Usually Ships** Today
Catalog Page No. 2495

we'll see how it goes...thx all - ed