teach me about hammer drills/rotary drills

[rfuerst911sc]

Javadog I thought buying this Bendpak branded install kit I was avoiding generic/unbranded ? Anyway it is what I have so I will use them . The foot plates on this Ammco branded Challenger lift are quite large so I think there is clearance for the drill . And the holes in the plates measure 3/4 with a tape measure so not oversized . I'll hit them with a caliper to get more precise measurement just to be safe .

[Eric 951]

As mentioned, no epoxy with wedge bolts. Don't drill with post in-place, make a template out of cardboard, or position post, mark holes, then move post out of way prior to drilling. Clean holes, position post, insert bolts(do not tighten), shim as necessary, then torque/tighten bolts.

[MBAtarga]

Drill all the way through the slab for your mounting bolts.

[javadog]

Originally Posted by rfuerst911sc

Javadog I thought buying this Bendpak branded install kit I was avoiding generic/unbranded ?

Hard to say, since we don't know where they get their anchors and they look to be unmarked.

My only point was that I tend to use products I trust and have used for a long time. There are a number of brands that I use, Hilti being the most frequent. As far as I'm concerned, they may as well have invented all this stuff.

I am in training to become a crotchety old fart and I am not a fan of the Chinese flooding our market with crap products, including hardware. I tend to avoid anything from China like it's radioactive, because so much of it is junk and I'm getting too old to buy useless crap. I build things for a living, I want to sleep well at night.

[rwest]

Originally Posted by rfuerst911sc

This is the install kit I purchased , it states they are wedge bolts . They are 3/4 " diameter so I drill a 3/4 hole correct ? No mention of epoxy but epoxy could be added right ? Or is there no value adding the epoxy ? In regards to the bit wandering I was planning on using the holes in the foot of each post as my drill guide that will work right ?

I figure I will drill the holes , insert shims as needed and install the bolts . If you guys think some epoxy would be good " insurance " then I will do so . I want to do this right the first time

https://www.carliftparts.com/product/bendpak-lift-installation-install-kit-16-wedge-anchor-bolts-30-pack-shim-kit/

Okay, I do these all the time. Here’s what I do and have good results. Mark the holes with a marker, drill 1/8” hole directly on center, drill recommend size much deeper than length of anchors- through slab is good, put your post in place, put the nuts and washers on the top of the anchor bolt just enough to cover threads, pound them in most of of the way, install shims and then finish driving them down and finally tighten with proper size wrench.

The “secret” is making sure there is plenty of depth and that you pound them in with the nuts on top to set them as deep as possible.

Guys at work never listen to me and do the measure and put in and invariably the dust fills the hole and the anchor doesn’t seat full length causing a lot of threads to be exposed above the thing you’re anchoring.

One other thing is that the anchor needs to be shorter than your slab thickness or it will just spin not wedge in place.

[ckelly78z]

Originally Posted by rfuerst911sc

Pretty soon I will be installing my 2 post lift . I will have to drill 12 holes 3/4 " in diameter and about 6 " deep . This concrete is high strength fiberglass reinforced and was poured aprox. 6 months ago .
.

.

I have the exact same scenario going on at my farm in my 40x60 pole barn. We dug out the old broken, thin concrete, and used multiple bags of 5000# HS concrete about 9" deep. I had health issues, and a stupid work load last fall, so I left it for this year. Tonight, I am going to use cardbaord to create a template to drill the holes in the concrete, but I will probably rent on Saturday morning. Renting on a weekday will get you 24 hours of use, renting on a Satrurday will get you 48 hours of use for the same money....and obviously more time to not have to rush.

[mussberger]

I sell a lot of 7/8" core drill bits for pool cover anchor installation. If you want a clean,straight, hole use a core drill.

[onewhippedpuppy]

Also, don't be lured into getting a standard drill with a hammer drill function. It's slightly better than a normal drill but nothing like a good dedicated SDS hammer drill.

[mfiazzo]

Rent a hammer drill from home Depot. best way to go

[mopydick]

I just purchased the GP-7LC model and started installation. I'm having an issue with the anchor bolts pulling back out as I torque them. I was careful to drill the 3/4" holes perpendicular and cleaned them well. The bolts took a bit of pounding to drive the expansion sleeve past the base plate and into the concrete, so I don't think I over-sized the holes.

I've only drilled and installed 4 bolts so far. Two of them seem to be working correctly yet the other two are pulling up with light torque (less than 20 ft-lbs).

I'm wondering if others have had this issue with their installations, and how they fixed the situation.

A contractor friend of mine says to just throw the mechanical anchors out, and buy Hilte brand epoxy and fasteners. But these do not come cheap, and it seems that the original mechanical anchor solution should work.

I'm tempted to use a bit of epoxy with the anchors that I have, to help the expanding portion of the bolt mechanism stay in place, but I've been told this is a big no-no.

Thank you for any input,

Peter

[rfuerst911sc]

Peter I did not have that issue when I installed mine . A few the bolt portion came up maybe 1/2 " to 3/4 " then stopped . I was able to torque all to 150 ft. lbs. so they held fine . I think you just need to keep trying .

[dad911]

Changed my tune, I agree with mfiazzo.... while I own a cheap sds drill and HF bits for small stuff, I rent the larger ones all the time.

Mopydick, don't use epoxy with a system it's not rated for. Did you drill deep enough? Screw not bottoming out? Which fastener? Pics would help.

I'd reach out to bendpak, surely this isn't an isolated question.

How old is the garage/concrete? Sure it's at least 4" thick? I can't tell you how many slabs we've cut/removed for renovations, and found concrete 2" thick or less.....

[1990C4S]

I do a lot of machine installations. Wedge anchors are inferior to chemical anchors.

Is wedge good enough? Likely yes, they certainly are if installed properly. Make the hole the right size, and vacuum the hole clean.

[NY65912]

We use Hilti Quad bits or core bits.

We are currently putting in 7800 ¾" x 7" SS Wedge Anchors on the RFK Triboro Bridge for 6" dry standpipe.

Get a good hammer drill 11/8" capacity will do. Drill nice and easy and use a baster to blow out the dust. Use domestic brand anchors like Hilti or Powers. Look up the embedment chart for your size anchor for best pull out number.

Use some duct tape to make a stop on the bit if needed. No need for overkill. I also like adhesive anchors but this requires a special gun but only uses a piece of threaded rod.

[gordner]

Hilti expansion anchors are about the best wedge anchor available.

The advice to drill through the slab is good advice, they are so much easier to pound down flush if you ever remove it vs grinding them flush.

[rnln]

Originally Posted by rwest

I found that drilling the holes first with an 1/8” bit helps to get the big holes lined up for accurate placement, otherwise they bounce around and the holes are off.

yes. Easier too.

[fastfredracing]

Interesting, I did mine a long time ago, but I was told by the Rotary lift rep, and installer, to epoxy my bolts . Maybe this has changed ??

[wdfifteen]

Originally Posted by stomachmonkey

That was too easy!

[mopydick]

Thanks for all the feedback. I'll take some pixs of what I have going this weekend when I get back to the garage.

To answer some of the questions:

- concrete slab was poured in the 1970's

- I drilled a test hole in the corner of the garage before ordering the lift, and found I could go 5" deep and still not pop out the other side. Maybe the the thickness varies from one area to another but I would have thought I would have felt the bit punch through the other side while drilling the holes that I have done.

- The threaded bolt head height of the ones that 'took' are about 1 to 1 1/2" above the nut.

- The loose ones are 2" or more and I feel that I could pull them out with some light force (haven't done it yet but I'm curious to see what the expanding end looks like now - maybe it got beat up to much when being driven in). I did have to hit them pretty hard to insert them (everything is relative but I do have some meat on the bones).

I did have the thought of using an impact wrench (with ultra low pressure) to give them a quick spin to see if I could get the wedge part to catch some concrete. I'm pretty sure once the wedging action starts, then one is home free, and torque slowly and methodically.

I won't be able to play with them again until this weekend and I'll take some pixs, and report back on any success or failures. I like the idea of drilling all the way through the slab and wish I had done it with the four that I've started. I'm also glad that I only drilled four and checked the fastening before drilling all 12.

Thanks everybody,

Peter

[aschen]

I read many stories about people struggling with the wedge inserts when I was doing my max jax install (on garage journal). This is why I went for the epoxy set inserts. It was expensive but I feel better getting under it with them. The pull out strength rating is something like 75% more for the ones I used and the install is more straight forwards.

One thing I absolutely would not do with this sort of thing is take any liberties in the mfg reccomendations. I found a lot of people recommending things that probably work, but there is too much risk to push your luck here.

Also I would not drill through if you are still undecided about giving the epoxy set anchors a go. You need the bottom of the hole in place.