How do you guys cut large holes into thick steel?
And how/when do you swage them?


I need to cut a large oval hole in some 3mm steel for my adjustable top mounts.
How do you guys do it at home?
I could use a hole saw and cut 2 holes (in this case each hole would be 40mm making say 65mm in length) overlapping other but that's a bit tricky and my hole saw might not like it too much as I would need to drill 4 holes.

Next question,
When do you need to swage a hole? And what for? Does it add strength?
How do you do it? Use a press and push a socket that's slightly too big through it? In my case 45mm?

Thanks

 

I have got a plasma cutter that would do a rough hole in that and then you could grind / file back to what you need. OR take it to a laser cutter.

If you measure out what you need then you can post it to me and I will cut within 10mm ish of how you and it and then you can cut back. Or some people multi drill then grind and file back. I have a mate who can get stuff lazer cut too if needed but not sure on cost.

If you are in South London you can jump on the A3 and pop down and you can use my plasma cutter as much as you like. Plasmas are under Ł400.

I do not know the answer to the swageing.

 

Cutting holes with the holesaw is simple enough. As long as there is a guide hole in the middle it will be fine.

Failing that, cut some other material, either wood or metal, say 5-10mm thick and drill a hole in this. Then set it on top, ideally bolt it to somehow and use this as the guide instead of a central drill hole.

Or drill lots of small holes around the perimeter and grind/file smooth after.

Or plasma cutter.

Swaging can look better and it can add strength to an otherwise flat panel. Yes you would need some sort of die setup to create the swage.

 

In answer to your second question. swaging is done to add strength/ridgidity to thinner sheet steel upto 1.5/2mm. typical uses are rollcage gussets & infill panels.
Dimple dies used to make swaged holes consis of a male and female 'cup' which when squeezed together (usually by means of a centre bolt) produced the flare. some also cut the hole too. others you have to cut the hole first and dress it.

 

Thanks Toby,
That's a very kind offer and if I wasn't going on a stag do this weekend I would love to take you up on it.
But I can't this weekend and don't know when I'd be free next to come down.
Would have been nice to have a nose around the pug at the same time.


I may post it down with a cardboard template and a box of beers if I get stuck.


Stevie,
Good idea with the wood template, I can easily do that but hadn't thought of it.

My hole saws do have a pilot bit, I can cut the plate oversized and screw a piece of Mdf to it and drill through. That should work well.
And I have thread cutting oil to keep the blade cool.


I like the swaging idea but it's probably not needed.

I will look into the tools to see if it's worth getting.


Cheers guys.

Can you tell I've bought a welder and am now a budding fabricator lol.

 

Do you have a compressor? If you do then I may be able to pop my Plasma in to you on my travels depending on where you are...i do not need it all the time.

Colin Satchell and Sandie Brown sell a swage kit I think, they are big in the pug world in the Cornwall area. I expect you can get them on ebay but I really doubt you need it.

My mate pays a couple of quid for each lazer cut hole I think.

 

http://stores.ebay.co.uk/FAB-PARTS-2009

these any help to ya, prices aint to bad.

 

I'm in Croydon, yes I have a compressor, is that what plasmid run off?

Very kind of you mate.
I will try the hole saw and wood template tonight to see if it works, if not I may take you up on the offer.

I called 3 local laser/water jet cutting people today.
The cheapest price was Ł50 and the dearest Ł75.
They all said minimum charge for setting up the machine.
So weather it was just the 1 oval hole or cutting the whole plate out to shape, the oval hole and 3 bolt holes it would be the same price and none could do it till the end of next week anyway.


Thanks for the eBay link, I will see how it goes once I cut the holes out.

Ideally I could take my piece of metal to someone to cut/swage the hole for a bit of beer money but that doesn't look likely lol.

 

for waterjet/laser etc

Ralph at www.componentengineering.co.uk

 

Yes, 3 pin plug and just an air compressor. Really easy to use. There are loads of "how tos" on youtube but it is a matter of earthing it like the clamp on a welder and just pull the trigger and away you go. The only adjustment is how powerful you want the cut to be in terms of thickness of metal but you cant really get it wrong.

I used mine to cut a household radiator in half the other day to fit it in my car for the dump.

Croydon is pretty close so let me know and I am sure we can meet part way if I am not that way.

Thanks for the eBay link, I will see how it goes once I cut the holes out.

 

If you get a swager, id advise the ones without hole cutter as they tend to work much better producing a neater swage and last longer.

 

Well I've made one side.
As I'm an impatient git I cut the shape with a grinder and cut the oval centre out with the hole saw.
I sandwiched the metal between 2 sheet of Mdf and just drilled it out the cleaned up the middle with a grinder.
This is my first ever attempt at welding and I did about 5 practice lines before getting bored and going for it.
I've never picked up a welder before today so be kind lol.
It doesn't look great but I will grind it down and seam sealer it anyway so you won't see it when I'm done.

Hole cut out and cleaned

New plate made and cleaned


Rested on top for good measure The plate is about 10mm bigger than the hole all round so I could have 2 overlap welds, 1 on top and 1 below.


Plate fitted underneath and All welded up



Welding getting slightly better lol


Underneath



And finished.



Only grinded it down a bit as its late.
Will clean it up and Seam sealer it later.

Overall I'm very happy with it.
Especially as Its my first attempt.

 

I dont get it ?

The plate is the same size as the strut tower ? Yet the weld looks like it is on a smaller diameter, not attached to the actual strut tower of the car ?

 

looks like to me that its been put in from the bottom and welded on the top.

 

I cut the plate to the same max size of the tower and then the hole I cut in the tower is about 10mm smaller all round.
I did this so I could fit the plate from below and have the top of the plate touching the bottom of the tower.
That way the old tower stops the new plate pushing up.
Also so I could have 1 weld around the smaller hole on the top of new plate and another weld around 10mm away on the bottom of the plate. So there are 2 separate rings of weld holding it in place.

An experienced welder could have fitted the plate on top and made a nicer job but for an amateur like me, this seemed like the safest way to do it.

 

Not a bad first attempt mate, looks ok after a grind down anyway, since you put the plate in from underneath it should be strong enough aswell

 

it's probably not attached all that well where you didn't get very good penetration (ooh er missus) and then ground the weld back, but not bad for a first attempt.

 

Well done, looks like job done and not going anywhere. If in any doubt turn up the mig and go over the weld again then grind back, I find you can really go for it once the weld has been done once. I have done far worse and seen no failure.

Great feeling when it goes right and a bad feeling when it doesn't. Keep up the good work

 

I think it will be fine and also wouldn't be to concerned about seeing the penetration on the back of the new steel to much as the new steel is probably 2-3 times thicker than what you welded it to, if you turn up the mig to high you mite start blowing holes