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Brit01 · Gold Cloverleaf Joined: 24 May 2010 Posts: 665

Hi guys,

Has anyone had experience with using the flex-hone tool to de-glaze bores?

Considering buying one to de-glaze before re-fitting pistons with new rings.

My old man is saying not to bother.

He's built loads of engines and just used emery papery to create an 'edge' for the rings to bed into.

Just concerned about getting the speed/forward-backwards motion correct to produce a nice finish using a drill.

Maybe less risky using emery paper by hand. I'm not sure.
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S2 33 1988 1.7 QV
Dellorto DRLA40 (32mm venturi)

ZeNiTh-PbArM · Posted: Wed Jul 06, 2011 7:05 pm Post subject:

Hi,

The best option is to have it done at a machine shop. It takes 10 minutes and does not cost much. The honing is made at the right angle and you're sure that your bores are perfectly circular afterwards (e.g. no compression loss)
Be sure to thoroughly clean the block afterwards, because the cutting fluid mixed with the sanding dust forms an abrasive compound.

Hand honing was used in the good old days when engines used to produce 50bhp per liter of displacement, but is not suited for modern or performance engines.
You could still use this technique if you were stranded in the middle of nowhere, but you'd better avoid it if you can.

Regards,
zp

Brit01 · Gold Cloverleaf Joined: 24 May 2010 Posts: 665

Guy Croft and members are telling me this is foolproof and is the only effective tool to do the best job by far.
It is self-centering and does an excellent job with no skills necessary. If you are a bit cautious just test it on a test pipe.

I'm stuck with no options as I can't take my block out really and the garages here will not do a good job at the cross hatch.
Apparently the flexi-hone is the best tool on the market to de-glaze.
Far better than the 3 stone tools, one of which I have in the house on a loan but will not use it.

I've seen plenty of pics and results of the flexi-hone and seems a good idea.

Fexi-hone is misleading - it's a de-glazing tool and will create a fine fine cross hatch perfect for ring seating. It will not remove material (well just a tiny tiny amount).

Thanks for your advice though.

Have a look at the flexi-hone site - very interesting.
http://www.brushresearch.com/
_________________
S2 33 1988 1.7 QV
Dellorto DRLA40 (32mm venturi)

ZeNiTh-PbArM · Posted: Wed Jul 06, 2011 9:32 pm Post subject:

Hi,

I use flexi-hone in small diameter for clutch and brake cylinder. I wouldn't use it for engine blocks unless I've checked beforehand that the bores are perfectly circular.
When honing blocks at a machine shop, it is interesting to see how the block vibrates at the beginning until the bores get perfecly round? I've already fine-adjusted brand new liners to pistons and they don't vibrate.

regards,
zp

JeremyC · Posted: Thu Jul 07, 2011 8:58 am Post subject:

I've used one several times on my Sprite engine and it's very easy to produce a good finish just keep it well lubricated and moving up and down.
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'93 Black 33 1.7 16v

Brit01 · Gold Cloverleaf Joined: 24 May 2010 Posts: 665

My bores are in very good shape, just need de-glazing,

Got 2 flex-hones on their way from USA. Just 30 USD each.
180 grit and 240 grit S/C.

Yes they tell me they produce excellent results and are easy to use.

Got advice from Guy Croft.
_________________
S2 33 1988 1.7 QV
Dellorto DRLA40 (32mm venturi)