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Old 13th Dec 2017, 8:40 pm   #1
M0FYA Andy
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Default Cutting Tufnol

Can anybody recommend the best power tool for cutting Tufnol and similar materials accurately and squarely. Thicknesses from tagboard material up to, say, an inch thick.
Should I be looking at bandsaws? Any recommendations for a good quality small bench-top machine? Looking at the various offerings, a lot look suspiciously similar, the only difference being the colour, so doubtless originating from the same factory in China or wherever.

Many thanks,

Andy
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Old 13th Dec 2017, 8:44 pm   #2
G6Tanuki
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Default Re: Cutting Tufnol

For flat/thin stuff, a Dremel in a clamp/jig will work [could perhaps repurpose one of the things used for Granite-worktop/tile-cutting? These are usually water-cooled too, which would be a Good Thing given the hazardous nature of SRBP and Tufnol dust]

For any cylindrical or square/fluted-section stuff like coil-formers I'd be using a lathe.
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Old 13th Dec 2017, 9:52 pm   #3
David G4EBT
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Default Re: Cutting Tufnol

It cuts easily on a bandsaw and is easy to drill too - no more difficult than a hardwood such as beech or oak. You can plane it with a newly sharpened plane taking fine cuts, but it blunts the blade quite quickly, then so does hardwood. Someone asked a while ago on the forum about drilling larger diameter holes and it only took a minute or two to drill the30mm diameter hole in the 12mm piece of Tufnol in the pic below, using a Forstner bit in a pillar drill.

Just don't use your lungs as an air filter!
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Old 13th Dec 2017, 10:39 pm   #4
M0FYA Andy
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Default Re: Cutting Tufnol

David, I was hoping you might answer! I think it might have been me who asked about drilling, and I have to report good results using Forstner bits. I've also found wood-working flat bits cut well, but the Forstner bits are better suited to a blind hole with a flat bottom. Similarly I've been sucessfully milling and turning the material.

So, if my assumption that a bandsaw would be be the best bet for sawing to size, to get good straight square cuts withour 'ragging' the edges, can anybody recommend a good accurate solid bench-top machine? (As opposed to a monster freestanding metal-working machine)

Andy
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Old 14th Dec 2017, 2:09 pm   #5
David G4EBT
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Default Re: Cutting Tufnol

Quote:
David, I was hoping you might answer! I think it might have been me who asked about drilling, and I have to report good results using Forstner bits. I've also found wood-working flat bits cut well, but the Forstner bits are better suited to a blind hole with a flat bottom. Similarly I've been sucessfully milling and turning the material.

So, if my assumption that a bandsaw would be be the best bet for sawing to size, to get good straight square cuts withour 'ragging' the edges, can anybody recommend a good accurate solid bench-top machine? (As opposed to a monster freestanding metal-working machine)
Firstly, if you're drilling thin material - acetate sheet, tufnol, metal, by far the best way to prevent 'snatching', which so easily happens with engineering bits, is to use a 'step drill' sometimes known as a cone drill. I quote often drill holes in 2mm acetate sheet up to 2" diameter and step drill is far and away the safest tool. EG:

https://www.amazon.co.uk/Hiveseen-Me...p+drills&psc=1

As to small bandsaws, which can be stood on or screwed to a benchtop, first, what not to buy!

I initially bought a Charnwood W711-8 mistakenly believing that it was made in Britain as it's emblazoned with Union flags and terms such as 'Woodworking Machinery at it's Best - Great Britain', the inference being that the machinery is made in Britain, though it doesn't actually say as such. (Charnwood don't seem to manufacture anything - they're just a marketing brand as far as I can tell). If fairness, the reviews on the whole seem fairly favourable, and it may well be that had I took up my disappointment with the company, they'd have been only two pleased to have helped.

On unpacking and assembling the saw, it became immediately apparent that is was poorly made and probably arrived in the UK after a long sea voyage. I had to rectify several defects, including with the two wheels, which were wobbly and out of balance, and the blade didn't run true. I almost sent it back and ought to have done as I was never happy with it and sold it after a year or so for about a third what I paid for it:

https://www.amazon.co.uk/Charnwood-W.../dp/B005BDNSZK

I replaced it with an Axminster 'Hobby Series HBS200N' Bandsaw which I've been happy with.

http://www.axminster.co.uk/axminster...bandsaw-102266

Much better built, though again, not by Axminster but to their spec, and I assume from the Orient. It some useful features, such as having knobs which you can turn to open the two doors to clean out the dust and change blades etc, rather than the more usual slotted screws. Unfortunately, with the fall in the value of the pound, the price has jumped by about £50 since I bought mine.

If I were buying one today, I'd probably go for a Scheppach HBS20 8in Hobby Bandsaw.

https://www.toolstop.co.uk/index.php...0240V%20(60103)

Scheppach is a German company, which does manufacture equipment, but that's not to say that the bandsaw is actually made in Germany. It looks a nicely made saw and at £125.00 is quite a bit cheaper than the competition.

They're all two-wheel saws of a similar size - about 720mm (28") high and about 475mm (18") square at the base, with a table of 300mm (12") square, a throat of 200mm (8"), and a maximum depth of cut of 75mm (3"). They come with a fence, a mitre gauge, and the table can be tilted up to 45 degrees. They all have quiet induction motors. They mostly have a 1/4" wide 6 TPI blade. You can get other widths and teeth according to your needs (for example, to cut metal), but 6TPI is a good compromise for most materials.

To get a wider throat requires a three-wheeled saw, which from my past experience, are dreadfully noisy.

A point to bear in mind when cutting thin sheet of any kind - veneer, thin Paxolin, acetate sheet, is that you must never do that without placing a piece of thin sacrificial wood, hardboard, MDF or whatever, beneath the sheet to support it. If you don't do that, at best you'll get a ragged cut, at worst, you fracture the material.

See the first pic below, which shows a 1mm thick piece of paxolin on a 5mm thick sacrificial piece of scrap ply.

The second pic shows the Charnwood, my 'ex' bandsaw, resplendent with it's Union flag and 'Great Britain' logo emblazoned on the front. The third pic is the Axminster one that replaced the Charnwood, which I've been pleased with. The fourth pic shows the depth of cut it can cope with - up to 75mm. The last pic shows the knobs which make it easier to gain access for maintenance than the usual slotted screws.

Hope that's helpful.
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Old 14th Dec 2017, 3:17 pm   #6
M0FYA Andy
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Default Re: Cutting Tufnol

David, many thanks for that. Informative as always.

I've been trawling the internet, and am focussing in on that same Axminster machine!

There seem to be at least a dozen 'makes' which look to be exactly the same machine in origin, including the the two you link to, however the Axminster variant looks to be the only one to adverise a cast-iron table, which I favour.

Would you recommend a blade with 6tpi for Tufnol? I was thinking more tpi might be better for a smooth cut, a bit like comparing a rip saw with a panel saw.

Thanks again,

Andy
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Old 14th Dec 2017, 6:31 pm   #7
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Default Re: Cutting Tufnol

I'm think you'd be pleased with the Axminster, which has a 3-yr guarantee. I'm sure mine came with the mitre fence, but that seems to be an extra now.
It's very useful not just for mitres, but if you're just cutting something that's say 75mm wide and 10mm thick at 90 degrees:

http://www.axminster.co.uk/axminster...e-fence-102919

When using the fence, always check with a set square that the fence is square and especially if you're cutting something say 2Ft long, try a test piece to make sure there's no 'run-out' and that it cuts exactly square. Also, use a square to make sure that the table is exactly 90 degrees to the blade so that when cutting thick material, the cut is exactly perpendicular.

As to the TPI of the blade, I think you might find 6TPI is fine because it's less likely to clog or overheat. The blade speed is 800 Metres per minute, so that's about 520 inches of blade per second passing through the material, and at 6TPI, that's 3,120 teeth per second. Probably best to familiarise yourself with it first, and do a few test cuts, then if you're not happy, try a finer blade. If you go to this link to 'The Bandsaw Shop' they sell bandsaw blades for every purpose in a wide range of lengths and thicknesses.

The blade length for the Axminster 'HBS200' ('Hobby Band Saw') is 1,400mm (55") long and you can get them in 6, 10 & 14 TPI. They cost 7.08 plus 1.95 post.

http://shop.thebandsawshop.com/shop/...bandsaw-blade/

A useful skill to acquire, is how to coil a bandsaw blade - quite a knack, which looks easy:

https://www.bing.com/videos/search?q...D9F3&FORM=VIRE

Hope that's helpful.
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Old 14th Dec 2017, 7:41 pm   #8
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Default Re: Cutting Tufnol

Quote:
Originally Posted by G6Tanuki View Post
For flat/thin stuff, a Dremel in a clamp/jig will work [could perhaps repurpose one of the things used for Granite-worktop/tile-cutting? These are usually water-cooled too, which would be a Good Thing given the hazardous nature of SRBP and Tufnol dust]

For any cylindrical or square/fluted-section stuff like coil-formers I'd be using a lathe.
I use a wet stone cutter with diamond tip blade, basically a tile saw, no dust and it cuts through it like butter with a very clean cut.
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Old 15th Dec 2017, 10:05 am   #9
M0FYA Andy
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Default Re: Cutting Tufnol

OK, I've ordered the Axminster saw!
Hopefully it will arrive early next week. I now have to make space on my bench, which demonstrates that tools and things being worked on behave just like gases - they expand to fill the space available!

Andy
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Old 15th Dec 2017, 12:47 pm   #10
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Default Re: Cutting Tufnol

Amongst other things, keep the band wheel surfaces and the inside of the blade clean, resin/saw dust build up is a killer for band saw blades, as is poor tracking, incorrect tension, incorrect feed speed (too fast) and trying to cut with blunt teeth etc.

Oscillating blade = bad news.

I used red diesel to lube the blade and wheels with on mine to help prevent resin build up, that in conjunction with brass scrapers on the wheels but even that wasn't enough, if left then eventually the blade would start to oscillate due to the inevitable build up of stuff so periodically I held a wide paint scraper blade on the back of the band saw blade and the wheel surfaces to scrape off the build up of crud....not for the feint hearted on a 4" wide 18ft blade with big gnashers travelling at 60 miles an hour in front of yer nose. Happy days.

I always stored my band saw blades open, for transporting wide blades the safest and best way to prepare them is to pinch them to a figure of eight between a strip of corrugated cardboard with the teeth offset then wrap the rest of cardboard strip around and tie off, then bring the two loops together between another strip of cardboard offsetting the teeth again and wrapping and tying off as before, doing it that way the teeth won't get damaged by clashing with each other.

Enjoy the saw Andy.

Lawrence.

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Old 15th Dec 2017, 3:13 pm   #11
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Default Re: Cutting Tufnol

Lawrence, it sounds like that bandsaw might be just a tad bigger than the one I'm buying............!
Andy
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Old 15th Dec 2017, 3:16 pm   #12
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Default Re: Cutting Tufnol

Just a little...

Although I have used a Scheppach.

Lawrence.
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Old 15th Dec 2017, 4:30 pm   #13
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Default Re: Cutting Tufnol

Concur the comments re Axminster kit. I have an Axminster morticer and sliding mitre saw - the Trade range, rather than the Hobby - and they're good solidly-built machines.

Cheers,

Frank
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Old 15th Dec 2017, 6:31 pm   #14
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Default Re: Cutting Tufnol

Quote:
Originally Posted by neil24-7 View Post
Quote:
Originally Posted by G6Tanuki View Post
For flat/thin stuff, a Dremel in a clamp/jig will work [could perhaps repurpose one of the things used for Granite-worktop/tile-cutting? These are usually water-cooled too, which would be a Good Thing given the hazardous nature of SRBP and Tufnol dust]

For any cylindrical or square/fluted-section stuff like coil-formers I'd be using a lathe.
I use a wet stone cutter with diamond tip blade, basically a tile saw, no dust and it cuts through it like butter with a very clean cut.
For cutting FR4 fibreglass PCB laminate I uses a 'Plasplug Compact' tile cutter which works a treat. Cost me a fiver at a car boot sale. Water cooled, but I use it dry - it cuts in a jiffy. They often pop up on e-bay, sometimes cheap others not so cheap. Several on there now, one used once to tile a bathroom - £20 B.I.N. (They're now about £80 new).

I wouldn't let FRB anywhere near a band-saw - it would blunt the blade in the blink of an eye.
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Old 15th Dec 2017, 8:02 pm   #15
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Default Re: Cutting Tufnol

Perhaps drifting off-topic a bit, but I have a Tufnol catalogue from 1962. It's easy to think 'Tufnol is Tufnol', but this lists a dozen different types, mainly with paper or fabric bases, but a couple with asbestos! I'm sure this won't be made any more, but worth bearing in mind.
The stuff I'm actually working with at the moment isn't genuine Tufnol, but a paper-based phenolic 'Tufnol substitute' which I chose as it is available in black, as I'm trying to replicate something originally made as a Bakelite moulding.

Andy
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Old 15th Dec 2017, 8:58 pm   #16
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Default Re: Cutting Tufnol

That sounds like the stuff I use Andy, which comes in black or brown in various thicknesses and sizes on e-bay from a supplier based in Hull. Good stuff - it has that characteristic phenolic smell, which I rather like!
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Old 15th Dec 2017, 10:47 pm   #17
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Yes, gfgplasticfabricationsltd in Hull. Good stuff.
Andy
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Old 16th Dec 2017, 10:31 pm   #18
robin coleman
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Default Re: Cutting Tufnol

There is a cutting disc that is sold by Tool Station that fits in an angle grinder, which builders use to cut cladding.

Regards, Robin.
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Old 17th Dec 2017, 11:12 am   #19
M0FYA Andy
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That doesn't sound like a precision tool to me............

Andy
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Old 17th Dec 2017, 12:58 pm   #20
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Default Re: Cutting Tufnol

Talking general wood based panels and bits of timber here (and maybe paper based sheets)... In the absence of a full blown panel saw the most accurate DIY method for straight cuts, 90 degree or angle, is to use a decent hand held circular saw and a proper guide track(s) system.

I have a Festool circular saw with a general purpose blade and a laminate blade, complete with set of Festool guide tracks and clamps that will do a 3 meter length of cut, the clamps fit in a full length slot underneath the guide track. The guide tracks are fitted with rubber splinter guards which fit right up to the job side of the kerf.

Deadly accurate, even doing 2.4 meter length mitre joints....Eeek!

Video to show what's what:

https://www.youtube.com/watch?v=4peebDA3PKw

Festool is more popular now with DIYers but back in the day Festool was a bit of a trade secret, had mine for about 18 years now and still it does it's stuff.

Lawrence.
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