Flow Drilling

[Welderpaul]

Any one any experience of flow drilling? I can get the kit for 650 odd quid, less about 35% discount. We have 900 holes to drill in 2mm wall 304L CHS, which need to be tapped M8. 2mm doesnt leave much meat for a machine screw to bite.
Not a great picture on the link, but do you think they will work on a pillar drill. Does the drill not just work harden the ss as it works its way through? The 'drill' must be made of some special stuff to cope with the heat. Glows red hot i think as it passes through.
Not really room for rivnuts to seat behind the fitting that screws to the CHS, so thats out.

This weeks learning curve

 

[Shox Dr]

I watched a few youtube videos on this a while back. While I'm used to seeing thin sheet with a thread formed like this, it never dawned on me how it was done.

Clever stuff. Get it bought and report back ASAP

 

[Welderpaul]

This looks similar to the one i've been looking at in the catalogues

And here
And here

 

[Shox Dr]

That's em

 

[Hitch]

Creates a fair lump on the back mind, probably not far off the size of a riv nut- but quicker and more reliable.

Theres a fair lump to spin, I think its a heatsink affair, on a morse taper
Always used it in a mill, powerfeed etc, i imagine it hard going on hand feed.


The bits 'em selves are solid carbide i think, and roll taps instead of normal ones too.
Been about 5 years since i last did it.

 

[Welderpaul]

Looks like the raised lump on the outside of the tube would need flap discing flush to let the fitting sit flush, which might allow the formed collar inside to come free?
Tungsten carbide they are made from.
You don't think our rubbish clarke pillar drill will be up to it then?

 

[Hitch]

Dont know, they need to spin a fair ol rate of knots. Got to need a fair bit of pressure i reckon.

The bit on the outside, i think theres different shape bits to avoid having that.

 

[Welderpaul]

What's Brian up to? Send him round for a bit - just his sort of work

We don't do much thin stuff, so not something that will get used too much, but may be worth buying for the savings in time/better quality job. I think you are right about the different shapes.

 

[Hitch]

Nothing is his sort of work.
Youll be welding them back up.


Hes off to Ireland for 10 days.
Get Mr Snowy on it, be alreet, perched on a stool, old fertilizer sack tied round his foot with some bale cord to keep it clean... sorted.

 

[hotrodder]

You don't think our rubbish clarke pillar drill will be up to it then?

Probably already found it but just in case the flowdrill site you linked to mentions 1000 - 3500rpm and 1.5 - 3.5kW ... http://www.flowdrill.com/english/reccomendations.htm#mtr

 

[jugs]

Looks like the raised lump on the outside of the tube would need flap discing flush to let the fitting sit flush, which might allow the formed collar inside to come free?
Tungsten carbide they are made from.
You don't think our rubbish clarke pillar drill will be up to it then?

NO - See THIS at 2 mins = flush

Brill kit , @ M8 you should be able to drill & tap 5 holes / min. BUT you need a good drill & aprox 3 hp

 

[Rick]

They'r awesome.

 

[Shox Dr]

Roll formed taps so the threads will be super good.

 

[TheJoker]

I've learnt something new today, thanks Gents!

 

[Lewis Medlock]

Have a look at Robert Speck LTD (no connection). They were demo'ing formdrilling at Mach10 last year, I've got a sample on my desk with flush holes and a raised collar.

They were really helpful at the show.

http://www.robertspeck.com/formdp.htm

Jim

 

[nickk]

flow drill costs

been reading up the archives on this,what are the costs of the bit ,i only have 60 m8 holes to m/c in s/s,& dont have any other jobs pending @ the moment,so it may not be viable,very strong joint though-a type of forging.