Board Logo

spot weld drill
donn - May 3rd, 2013 at 12:39 PM

Somewhere I picked up that there is a special drill for removing spot welds to make it easier to remove panels, (I've always used a normal drill bit) I've asked at a few places only to be greeted with a blank stare. Is there such an animal, if so what's it calledl and where would be the best place to get one.
Thanks
Don


68BUS - May 3rd, 2013 at 01:23 PM

This page shows both.
The black shoud turns round to give 2 cutting edges.
The one with out a shoud I think is better but tries to run a little bit still when you first start.
You can also reduce the angle of a normal drill with a fine grinder blade.

The concept behind them is hey are more shallow cutting so you can take out the spot weld without drilling through the 2nd piece to make rewelding easier.
http://www.ebay.com.au/itm/BGS-Germany-10-pieces-Spot-Weld-Cutter-Drill-Bit-S...


gordysbeetle - May 3rd, 2013 at 01:29 PM

There is a couple of types i have seen. One is like mini hole saw with a centering point in the middle. The other is a sheet metal drill which is sharpened the reverse to a normal drill ( cuts from the outside first. They are sharpened like this to give a round hole ) Auto stores and auto paint suppliers should have them.


donn - May 3rd, 2013 at 02:01 PM

Cool Mr. Bus, I've sent a question to get a bit more info off them. :yes:
gordy, thanks, the ones in the link look like what you are describing. :tu:


68BUS - May 3rd, 2013 at 03:15 PM

You can get cheaper ones too Donn.
The ones I linked to look to be a good german steel though.


psimitar - May 3rd, 2013 at 06:52 PM

Heard them called Brad drill bits here.

I bought mine from Ebay UK. 6mm and 8mm cobalt for about $10 inc P&P and that was for 5 drill bits.

Only worn one of them out so far and just sharpened it using a 1mm slitting disc on the grinder :)


hellbugged - May 3rd, 2013 at 07:22 PM

Wurth make them

They are great!

Ebay


Special Air Service - May 3rd, 2013 at 08:43 PM

http://sykes-pickavant.com/Portals/0/PDFs/Bodyshop%20Tools/Body%20Repair%20To...


psimitar - May 3rd, 2013 at 09:14 PM

here ya go. Cheap and good quality

Spot Weld bits Ebay


Lucky Phil - May 3rd, 2013 at 09:30 PM

Bought one at great expense to replace a pan 1/4 and couldn't get into the welds cos the drill was too short.
Persisted with ordinary drills and had no problems.


helbus - May 3rd, 2013 at 09:47 PM

They are short bits in 6mm and 8mm. They can be used in ordinary drills and also special spot weld drills.


matberry - May 3rd, 2013 at 09:52 PM

We use $20 Wurth ones

IMO the ones in the link are too fragile and the small drill puts a hole in both panels which is a pain


Doug Sweetman - May 3rd, 2013 at 10:07 PM

eBay .... You can get ones which (with practice) will leave only a small divot on the bottom panel. HSS is fine with body panels but be careful not to push too hard and overheat them, they will blunt quickly if you do.


psimitar - May 4th, 2013 at 01:11 AM

Quote:
Originally posted by matberry
We use $20 Wurth ones

IMO the ones in the link are too fragile and the small drill puts a hole in both panels which is a pain


Yup, those weird mini holesaw ones aren't worth bothering with IMO.

Seriously tho the link I gave is a great bargain. They are Cobalt steel so better than HSS and took multiple panels over 3 years to blunt the first of them.
A steady hand and a 1mm slitting disc managed to resharpen the cutting edge and so it soldiers on :)


gordysbeetle - May 4th, 2013 at 07:56 AM

I have found the mini hole saws to be brittle. Like everything you get what you pay for. Wurth products are expensive but you can't buy better. If anyone is having difficulty ( like me ) Hare and Forbes sell sharpeners for sheet metal drills but I don't have a spare $1400.00.


donn - May 4th, 2013 at 04:50 PM

Well, ask and you do receive on this forum, once I knew what I was after I troted off to Gasweld and bought one (the drill type) cost me a bit over $20 for one drill, it had better be worth it at that price. I'll probably get one of those other kits as a back up but I wanted to get started straight off and didn't want to wait for delivery.
Thanks
Don


modulus - May 4th, 2013 at 07:14 PM

Quote:
Originally posted by donn
cost me a bit over 420 for one drill


Hopefully that is $20, with a bit of shift allergy.

hth


HappyDaze - May 4th, 2013 at 07:27 PM

Could it have been $@) ?


donn - May 6th, 2013 at 04:40 PM

Ho ho, yes $20 (check, yep, typed correctly) :crazy: looks like I could have waited as the bloody flue has got me and I still haven't started. :grind:


HappyDaze - May 6th, 2013 at 05:27 PM

Good work donn........now you've got the drill.:rolleyes:


1303Steve - May 6th, 2013 at 10:10 PM

hi

Make sure you use some cutting oil on it.

Steve


Klaus - May 8th, 2013 at 11:20 AM

make your own , I've made them up to 14mm to remove plug welds in ute trays bench grinder is your friend


HappyDaze - May 8th, 2013 at 01:15 PM

I agree, Klaus.....you need a good 'square' corner on the grinding wheel, though, particularly for the small drills.

Keep the cutting speed down, and use cutting fluid, as Steve says. Water is good...and cheap.


donn - May 8th, 2013 at 04:15 PM

Yeah, I thought of making my own once I'd seen exactly what they are so I went out and rescued a couple of broken 5mm bits to try out on, hmm, gonna need a bit of practice but I think I'll get it eventualy. I'm having the best result so far cutting the drill square with a slitter disk and then grinding on my wet wheel, once this bloody flue is gone I'll give the "made" ones a go and compare them with the bought one.


1500S - May 10th, 2013 at 11:58 PM

Thought I'd add this. Dress a 30 degree bevel on the edge of the grinding wheel (pref 60 grit) which will give you the small 60 degree centre point and you can make as many as you want from a standard twist drill. Just a steady hand and a bit of practice!