Driver Choices for Cabinet Assembly Confirmat Screws

Cabinetmakers discuss the options in cordless, corded, and air-powered drivers for cabinet assembly using Confirmat screws. June 17, 2012

I'm looking for a better driver solution for assembling cases with 5x70mm confirmat screws. I currently use a Bosch 12volt cordless impact. It is surprisingly strong when the battery is at full charge but in my opinion slow, and slower as the small battery gets drained. I am looking for a pneumatic or cordless driver. I have tried a pneumatic non-impact driver (stalls before fully driving), a corded drywall screwdriver (fast but the clutch is tricky, itís loud, and strips screw heads), and finally the afore mentioned Bosch 12v impact.

My budget is in the $100-300 range if feasible, but Iím willing to push further out for a sure enough, top notch driving solution. Iím considering a Beaver Tool BT302- Ballew Saw, and a Makita BT141 18v impact (actually compact and no hose really appeals to me).

Forum Responses
(Cabinetmaking Forum)
From contributor Y:
The best driver I have used is a Hitachi 18v impact. It may be the impact, not the brand. I did have a 12v Hitachi that worked well also.

From contributor C:
We have run the heck out of the Hitachi 18v cordless and received great results. The same goes for the 18v Dewalts. All of them are impacts.

From contributor F:
It sounds like the biggest hurdle is the battery life, correct? I think I'd echo the others and say buy a new cordless drill and additionally maybe consider buying an extra battery or two. As soon as the drill starts slowing down you swap batteries.

I like Makita's myself and just bought a new 18v kit yesterday. All the reviews I read confirmed that it's a quality tool. However, be aware they have two different batteries for these drills - something like 1.6 and 3 amp per hour. For what youíre doing it would be worth the extra expense of the higher amp hour (longer run time) battery. Less expensive drills come with the lesser amp hour batteries.

From contributor L:
Confirmats are sized by shank diameter, since I'm not aware of any 5x70's, you must mean 7x70. Is there a reason you are using 70mm long confirmats? 50mm is plenty for 3/4" stock (5x40 for 1/2"). The 70mm ones I've seen call for a 5.4mm end bore.

From contributor O:
Have you seen the DeWalt DCF885L2 yet? Itís an inch shorter and is lighter that the Bosch, and it sports a 20V lithium Ion battery. It's amazing. Don't know what the long-haul life will be though.

From the original questioner:
My mistake on the size - not 5x70 but 5x50. It calls for 7mm thru holes and a 5mm end bore. Still tricky though. The main issue is speed. The smaller impact drives it, but the rpms aren't there at load.

From contributor F:
I think youíre going to have to compromise a little. Cordless drills with the ability to drive confirmats fully are (generally speaking) going to be high torque, lower speed. Impacts drive fast with no load, but once load is applied they slow right down.

Even air impact drivers are lower speed than standard drills. The Beaver screw guns run at about 700 rpm's. The drywall gun you mention will likely be the fastest of your options. Are you using confirmat driver bits? I only ask because I've seen guys using regular Phillips and stripping the heck out of the screws. I use an older Makita 14v impact drive and find it fast enough for my needs.

From the original questioner:
To contributor J: I am using a #3 pozi drive bit, no slippage, but as you stated the drywall gun is entirely too fast and the clutch is tricky bad. Have you done a test run on the Makita? Whatís the battery life?

I seriously considered the Beaver, in fact ordered one, but Ballew Saw called and said no longer available. 700 rpm seems slow anyway, plus dragging the hose around shoots that deal down. I am leaning towards the Makita 18v 3.0, as I don't like the yellow stuff. I just don't want to spend $250-300 getting halfway to where I want to go.

From the original questioner:
On a side note, I pre-bore on a Maggi 2332, with a 7mm throughbore and 5mm endbore, but sometimes the screw (with nibs) spins out (strips) before pulling the screwhead below suface,

Should I drop back my endbore hole size to 4.76 to tighten the hold? Iím using high density temple yellow pine particle board with looser core and denser particles at face surfaces.

From contributor F:
I only purchased the 1.5 amp hour version. I may pick up a couple of the 3 amp hour batteries in the future if needed. I was/am very tempted to get the Beaver impact, I will say though I was a little disappointed at the quality of their regular 3/8" drill. After a couple hours of use the screw inside the chuck fell right out.

I find materials make a difference in how well they countersink. I bore all my holes on an old CNC boring machine so they're all exactly the same. In plywood, which is most of my work, no problem, sinks right in. In melamine, hit or miss, though many miss. I actually started using a chamfer bit in a second drill during assembly, as I was stripping too many out. It's a pain, but I haven't done enough melamine to invest time in experimenting with remedies. I was thinking about trying the self-coutersinking screws, but it sounds like those are the ones youíre having trouble with, so maybe not worth the extra money?

From contributor L:
All the Hafele confirmats I have acquired are undersized. Like all screws, confirmats will be strongest (and align the parts best) if the thread pilot hole is the same size as the thread root/minor diameter. On my 7/5mm confirmats itís 3/16" - a lot less than 5mm. I've also changed my tune on self countersinking. Confirmats have a relatively small/thin head that is relatively easy to sink into melamine/PB without nibs - when using appropriate sized holes. I haven't tested, but my feeling is that nibs require at least as much torque to countersink.

The earlier thread prompted the testing, but I have not had a chance to make adapters and test 3/16" in production yet. I've been using smaller (5/32") pilots on 5/4 confirmats for some time, but the testing showed 9/64" works better so I'll be making adapters for those as well.

I've been hesitant to comment on impact drivers because I've only used one once. I thought the point of using them was the additional torque. Driving confirmats doesn't require that much torque, even a 7.2v Metabo drill/driver can countersink plain head 7/5 confirmats on low (3/16 pilot).

From contributor L:
We've been using Makita impact drivers for years, very durable. The 18V lithium powered ones come in several models. Don't get the smallest one. Also get the higher capacity batteries, (expensive) but they work great. Use a #3 Posidrive bit.

From contributor B:
We use a Master Power #2462-M (1000 rpm) air tool by Cooper Power Tools with a #3 Phillips bit. It has a ratchet type clutch easily enough power to counter sink confimats. We drill 5.2mm holes in our vertical pieces. No batteries to charge, no batteries to replace, and no batteries to dispose of. I bought three or four of them at the Hartford woodworking show six or eight years ago. They aren't pretty anymore but I never had to fix them either (even after many drops on the floor).

From contributor L:
You got my curiosity up about the size of our confirmats (not Hafele brand.) I just measured one: root 4.85mm, upper 6.82mm, O.A.L. 50.08mm conclusion - close enough. We drill with 7mm and 5mm bits. They self-countersink into raw industrial PB fine. For melamine you have to push pretty hard so we pre-countersink. If you use them into the edges of MDF you need to use a larger pilot hole to keep from splitting the board.

From contributor F:
I purchased a Makita and here are my short term impressions of it.


1. Much lighter than my previous Makita 14v.

2. Has lights on both drill and impact - very handy if you do installs.

3. Batteries really do charge in about 15 minutes..


1. Battery life is pretty short.

I have to say I like the drill and am pretty happy with it. If I wanted to drive screws all day I'd either buy a couple extra batteries, or pick up the three amp hour versions, but for my use the 15 minute charge is a big improvement over my last drill, so I think the trade-off is a good one.

From the original questioner:
The 12 volt Bosch drives them well when the batteries are at full charge. I have around eight batteries that I cycle through the charger, it just takes some more thought on my end to remember to swap them.

I think your suggestion on the compromise was on target. An impact is slower RPM, but the Makita was rated a tad bit slower RPM than the Bosch 12v, so no real advantage other than run time, and the Confirmats drive easy anyway.