Discussion
There are two main problems with the Dremel, lack of power to shift material and lack of size to use reasonable size tools for removing material. If you were to use a flexible shaft in a drill you should be able, with patience, to port your heads and manifold. If you look at Eliot's piccie of all the grinders and tool attachments you will see a few with emery cloth wound around them. This is a good way of smoothing and blending. Get some mild steel round bar(say 8 mm threaded bar), cut a length of of around 125 mm, slot the end (from one tip of bar) with a hacksaw (25mm slot). Buy some 25mm x 60 grit emery cloth. Fit the bar into the flexible shaft chuck leaving around 100 mm as the extension, tear off some emery cloth and wrap it anti clockwise if the drill has a clockwise rotation..... get porting. You can also use the emery cloth by hand to smooth ports.
Most novices make the mistake of thinking if they mod the big, easy to get at, holes they will get best power gains, this is not so as most gains are with careful work around valve throats, valve seats and valves. For a lot of the valve lift/close cycle the port will not have a significant effect on most heads, it is the areas that affect where the valve first cracks open to around 6-8mm lift you can get the best gains on most heads, especially for road use.
Peter
Most novices make the mistake of thinking if they mod the big, easy to get at, holes they will get best power gains, this is not so as most gains are with careful work around valve throats, valve seats and valves. For a lot of the valve lift/close cycle the port will not have a significant effect on most heads, it is the areas that affect where the valve first cracks open to around 6-8mm lift you can get the best gains on most heads, especially for road use.
Peter
one eyed mick said:
^ listen to a master!!.
Indeed. What Peter says makes perfect sense. I don't know why it alluded me in the first place 
Sometimes the simplest solutions are right under your nose!Right, I'm off to Screwfix. I might even try and weld one of the wire brush attachments I have, to some rod. IF I can weld it straight that is...
Thanks chaps
For info
If you use a Dremel it will burn out...or you will.
I use one of these -
http://www.amazon.co.uk/Bosch-Professional-240V-St...
And buy burrs from here -
http://www.abrasive-systems.co.uk/spindle-mounted-...
If you use a Dremel it will burn out...or you will.
I use one of these -
http://www.amazon.co.uk/Bosch-Professional-240V-St...
And buy burrs from here -
http://www.abrasive-systems.co.uk/spindle-mounted-...
denisb said:
For info
If you use a Dremel it will burn out...or you will.
I use one of these -
http://www.amazon.co.uk/Bosch-Professional-240V-St...
And buy burrs from here -
http://www.abrasive-systems.co.uk/spindle-mounted-...
You can get them with a thinner and longer nose so they may fit in deeper if port size permitsIf you use a Dremel it will burn out...or you will.
I use one of these -
http://www.amazon.co.uk/Bosch-Professional-240V-St...
And buy burrs from here -
http://www.abrasive-systems.co.uk/spindle-mounted-...
http://www.amazon.co.uk/Makita-750W-240V-Speed-Gri...
http://www.amazon.co.uk/s/ref=nb_sb_noss_2?url=sea...
I agree with Eliot's Dad, we only use air grinders. We have far more control and a stall situation is not as frightening. I do have a flexible shaft grinder, a 1/4hp Derotor pendant foot controlled grinder but it is best suited for very light work and a snag is still a little worrying. I can use it where I have no air supply, which, I suppose is why most home head modifiers use electric based grinders of some kind, whether high speed or drill based low speed. On the plus side, in the winter, electric based ones are warmer to the hands!
Peter
Peter
Eliot,
Thank you very much for sharing your Dad's secrets!
As said above, it's craftsmen like him that are missing these days.
The extensions he made for the burrs are intriguing. I can see how they helped prevent 'helicoptering', as they start thick at the base and thin out to the end, in other words they are strongest where the leverage is greatest - first class engineering. But how did he make them, and what from? I presume they screwed onto a threaded shank in the grinder, using either the hexagonal base or the tommy bar hole? Did your Dad fabricate them from bar, or did he have a original part that he adapted?
I hope he would agree to sharing his real secrets with enthusiasts today!
John
Thank you very much for sharing your Dad's secrets!
As said above, it's craftsmen like him that are missing these days.
The extensions he made for the burrs are intriguing. I can see how they helped prevent 'helicoptering', as they start thick at the base and thin out to the end, in other words they are strongest where the leverage is greatest - first class engineering. But how did he make them, and what from? I presume they screwed onto a threaded shank in the grinder, using either the hexagonal base or the tommy bar hole? Did your Dad fabricate them from bar, or did he have a original part that he adapted?
I hope he would agree to sharing his real secrets with enthusiasts today!
John
Thanks again for the replies chaps.
So I have already bought this: https://www.machinemart.co.uk/p/crt40-40pce-rotary...
and this: https://www.machinemart.co.uk/p/100pce-accessory-k...
And ordered this yesterday: http://www.screwfix.com/p/flexible-drive-shaft-915...
I haven't used them yet, so can return them if need be.
The reason I say this is is the consensus seems to be that air die grinders are most effective. The trouble is, I don't have a compressor. So then you start to ponder whether buying one is overkill or a sound investment. Also, my budget for restoring the Chimaera is starting to run away a bit, and I've already made the decision to not have the seats re-leathered at a cost of over £1100, and go for the furniture clinic kit to restore the existing stuff. Just to balance up the budget.
So if I go down the air route, what else will I use it for? And how much more room is it going to take up in a garage I'm trying to keep clutter free? And the most important question, how much is it going to cost?
I already have a Sealey impact driver, so wont need a hammer gun. What else, apart from grinding and possibly spraying is it going to be needed for? Sure blowing debris out of hard to reach places is very handy.
The real question is, how much air capacity air compressor am I going to need to make it worth while having? So I can have a window shop
Cheers
So I have already bought this: https://www.machinemart.co.uk/p/crt40-40pce-rotary...
and this: https://www.machinemart.co.uk/p/100pce-accessory-k...
And ordered this yesterday: http://www.screwfix.com/p/flexible-drive-shaft-915...
I haven't used them yet, so can return them if need be.
The reason I say this is is the consensus seems to be that air die grinders are most effective. The trouble is, I don't have a compressor. So then you start to ponder whether buying one is overkill or a sound investment. Also, my budget for restoring the Chimaera is starting to run away a bit, and I've already made the decision to not have the seats re-leathered at a cost of over £1100, and go for the furniture clinic kit to restore the existing stuff. Just to balance up the budget.
So if I go down the air route, what else will I use it for? And how much more room is it going to take up in a garage I'm trying to keep clutter free? And the most important question, how much is it going to cost?
I already have a Sealey impact driver, so wont need a hammer gun. What else, apart from grinding and possibly spraying is it going to be needed for? Sure blowing debris out of hard to reach places is very handy.
The real question is, how much air capacity air compressor am I going to need to make it worth while having? So I can have a window shop
Cheers
Oddly enough i've got a draw full of air grinders as I prefer electric. I do quite a lot of porting now so being a Yorkshireman the size of my electric bill was an issue, it didn't take a genius to work out which is cheaper to run (by a country mile), the huge motor on my compressor or the small one on a grinder, not to mention the numb cold hands and noise it makes rumbling and clattering away in the corner, at least when I stop the grinder now I can answer the phone without running into the office.
The other point was that because I was using one machine to power another I had twice the maintenance costs and wear and tear which was a bit daft when I thought about it.
The bigger ones do feel a bit cumbersome at first, but like any tool in regular use; you adapt. The controllability of it was easily overcome by plugging it into a foot pedal which works like a car accelerator.
A lot of head porters swear by an old Makita which is a lot smaller than the one in the link above and now quite difficult to find as they went NLA, but apparently someone in Japan has started to make them again and you can get them on Amazon.
I wouldn't suggest a hand held electric (as opposed to the shaft driven ones) to a beginner, in the wrong hands they can be quite dangerous.
The other point was that because I was using one machine to power another I had twice the maintenance costs and wear and tear which was a bit daft when I thought about it.
The bigger ones do feel a bit cumbersome at first, but like any tool in regular use; you adapt. The controllability of it was easily overcome by plugging it into a foot pedal which works like a car accelerator.
A lot of head porters swear by an old Makita which is a lot smaller than the one in the link above and now quite difficult to find as they went NLA, but apparently someone in Japan has started to make them again and you can get them on Amazon.
I wouldn't suggest a hand held electric (as opposed to the shaft driven ones) to a beginner, in the wrong hands they can be quite dangerous.
Edited by Evoluzione on Monday 8th February 10:51
I think I would buy this if you have room, https://www.machinemart.co.uk/p/se16c150-air-compr... I used two of these until I could buy 2 x 5.5 three phase compressors ( one spare incase of failure!) We produce around five modded heads a week so need to ensure we can stay in production, I guess that means we have done around 7000 modded heads since I started full time!
Most airgrinders will use around 9cfm actual. The air compressors are rated as free air delivery and will only give around 75% actual air delivery. The one I linked to would give approx 10.5cfm which is enough to run a diegrinder. It is expensive setting up for using air diegrinders, but, as you say, you can buy myriad other air tools too.
Peter
Most airgrinders will use around 9cfm actual. The air compressors are rated as free air delivery and will only give around 75% actual air delivery. The one I linked to would give approx 10.5cfm which is enough to run a diegrinder. It is expensive setting up for using air diegrinders, but, as you say, you can buy myriad other air tools too.
Peter
Electric and flexible shaft is probably most practical for DIY'er with no air compressor.
There are pro's and cons on both sides. Noise with air is very irritating, as is the cold air constantly blasting your hand, plus they consume a lot of air, so really need an air supply that's up to the task.
And it really doesnt take a lot of usage for air to struggle.
There are pro's and cons on both sides. Noise with air is very irritating, as is the cold air constantly blasting your hand, plus they consume a lot of air, so really need an air supply that's up to the task.
And it really doesnt take a lot of usage for air to struggle.
tapkaJohnD said:
Eliot,
The extensions he made for the burrs are intriguing. I can see how they helped prevent 'helicoptering', as they start thick at the base and thin out to the end, in other words they are strongest where the leverage is greatest - first class engineering.
Some are made from hex bar stock and some are just plain round stock. They are threaded and screw into a male thread on the die grinder - which I appreciate few die grinders actually have nowadays. Although the "new" one we got of ebay with the blue handle did have a male thread on it.The extensions he made for the burrs are intriguing. I can see how they helped prevent 'helicoptering', as they start thick at the base and thin out to the end, in other words they are strongest where the leverage is greatest - first class engineering.
The ones made from round stock have a simple hole drilled across so you tighten them onto the grinder.
The burs are are simply held in on lock-tite alone.
I've uploaded larger pictures onto my webpage - if you clear your browser cache you should get the VERY LARGE photos when you click on the small ones.
caduceus said:
Thanks again for the replies chaps.
So I have already bought this: https://www.machinemart.co.uk/p/crt40-40pce-rotary...
and this: https://www.machinemart.co.uk/p/100pce-accessory-k...
Cheers
That 1/8th stuff looks a bit of toy to me. I can understand not wanting to get a compressor - so get an electric die-grinder with 1/4" shaft with industry standard burrs is what you need.So I have already bought this: https://www.machinemart.co.uk/p/crt40-40pce-rotary...
and this: https://www.machinemart.co.uk/p/100pce-accessory-k...
Cheers
A foot pedal speed control will make it far less scary and nicer to use.
Thank you, Eliot!
For porting, as mentioned above, burrs like your father used are MUCH quicker than abrasives, and provide a nice rippled finish that is better than polished, as it discourages wall wetting with fuel.
What compressor? Cubic Feet per Minute (CFM) is the key; see the usage which any tool should state, on it or its packaging, and get a compressor that is delivers at least that much plus a bit (20%?)
Direct drive, not belt driven, compressors are compact and a bit cheaper, but also a LOT NOISIER!
OK if you can position the compressor in an outhouse, but they make the garage/workshop too noisy for conversation of even a radio at reasonable volume.
What other tools may usefully be air-driven? Just an air blower is invaluable for rapid drying after parts are cleaned, keeping flash rust to a minimum, and a tyre inflator is obvious but very useful. I use an underseal applicator as a blower, because it entrains a lot of ambient air as well as the pressurised supply. Without the underseal cartridge, of course.
Also I have an air hacksaw that can get into places that a hand saw never could, and an air belt sander, the one with half-inch belts. Remarkably effective, can remove material almost too quickly, but also can polish metal parts from rusty to gleaming in no time.
There's a host of other air tools I covet, planishing hammers, pop riveters, quite apart from the obvious paint sprays, but the one I would really like is this kit that uses compressed air to cause a vacuum in the cooling system and sucks out all the coolant, so that it can be replaced without air locks. Seen it in use, and impressive.
https://www.machinemart.co.uk/p/draper-expert-cool...
John
For porting, as mentioned above, burrs like your father used are MUCH quicker than abrasives, and provide a nice rippled finish that is better than polished, as it discourages wall wetting with fuel.
What compressor? Cubic Feet per Minute (CFM) is the key; see the usage which any tool should state, on it or its packaging, and get a compressor that is delivers at least that much plus a bit (20%?)
Direct drive, not belt driven, compressors are compact and a bit cheaper, but also a LOT NOISIER!
OK if you can position the compressor in an outhouse, but they make the garage/workshop too noisy for conversation of even a radio at reasonable volume.
What other tools may usefully be air-driven? Just an air blower is invaluable for rapid drying after parts are cleaned, keeping flash rust to a minimum, and a tyre inflator is obvious but very useful. I use an underseal applicator as a blower, because it entrains a lot of ambient air as well as the pressurised supply. Without the underseal cartridge, of course.
Also I have an air hacksaw that can get into places that a hand saw never could, and an air belt sander, the one with half-inch belts. Remarkably effective, can remove material almost too quickly, but also can polish metal parts from rusty to gleaming in no time.
There's a host of other air tools I covet, planishing hammers, pop riveters, quite apart from the obvious paint sprays, but the one I would really like is this kit that uses compressed air to cause a vacuum in the cooling system and sucks out all the coolant, so that it can be replaced without air locks. Seen it in use, and impressive.
https://www.machinemart.co.uk/p/draper-expert-cool...
John
Edited by tapkaJohnD on Monday 8th February 18:29
Check this one out - that must be about a meter long:
http://www.ebay.co.uk/itm/K912-500-9-Desoutter-Str...
This one looks useful:
http://www.ebay.co.uk/itm/FUJI-DIE-GRINDER-FG-3VX-...
http://www.ebay.co.uk/itm/K912-500-9-Desoutter-Str...
This one looks useful:
http://www.ebay.co.uk/itm/FUJI-DIE-GRINDER-FG-3VX-...
eliot said:
Check this one out - that must be about a metre long:
http://www.ebay.co.uk/itm/K912-500-9-Desoutter-Str...
That's a tool and a half, i'd feel like Luke Skywalker brandishing that http://www.ebay.co.uk/itm/K912-500-9-Desoutter-Str...
Hi Mike
I would be happy to show what we do to road spec heads, a matter of where to post the info? We seem to be doing a fair few V8 heads at the moment so could produce pics of the various stages of work involved with each spec. I am not bothered about lines and lines of flow figures, I was thinking in terms of descriptions and pics of what works and how to do it, eg bullet the inlet guides and shorten em in place?
Peter
I would be happy to show what we do to road spec heads, a matter of where to post the info? We seem to be doing a fair few V8 heads at the moment so could produce pics of the various stages of work involved with each spec. I am not bothered about lines and lines of flow figures, I was thinking in terms of descriptions and pics of what works and how to do it, eg bullet the inlet guides and shorten em in place?
Peter
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