Domed hones?

i have in the last few months cought a very bad case of HAD.in lapping many hones all of them were high in the middle even the ones that were sold as "lapped" in fact the only dished stones i have lapped are the ones that i have used for 30 years in my workshop.now this makes me wonder if iam doing someing wrong or if other people have had the same experience? my hones are flat as far as i can tell.iam now lapping a arkansas tranlucent 8X2 3 days in useing 2 dmt 320s, realy alltogeather iam lapping this rock for at least 5 hours and its just the edges that dont touch the dmt. feedback?

It could be whatever they used to lap on was dished or they used flexible diamond plates. The current sanding mesh sheet I have in use is dished so whatever I lap with it comes out domed. I used to have cheap diamond hones, they were fast but nothing came out perfectly flat :D

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Originally Posted by cutalot

.iam now lapping a arkansas tranlucent 8X2 3 days in useing 2 dmt 320s, realy alltogeather iam lapping this rock for at least 5 hours and its just the edges that dont touch the dmt. feedback?

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Are you saying you've worn out 2 DMT 320's try to lap a translucent Ark. ? It could be your lapping technique that's causing the dome . If that's the case , you could lap it until the cows come home , and it would still be domed .

yes iam useing 2 dmts but not at the same time . the thing is that every hone i lap starts out domed. the flat starts in the middle and depending on the hone works slowly or in the case of the Ark. very slowly out to the edge. i was wondering if other people have seen this. i have lapped maybe 20 hones in the last few months

A lot of domeing can happen if the person is rushing and pushes on the hone. this causes it to rock and make doming. Another one I have seen is when lapping plates of the hone lapping machine are worn out and dished.

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Originally Posted by cutalot

yes iam useing 2 dmts but not at the same time . the thing is that every hone i lap starts out domed. the flat starts in the middle and depending on the hone works slowly or in the case of the Ark. very slowly out to the edge. i was wondering if other people have seen this. i have lapped maybe 20 hones in the last few months

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I suppose some might come from the maker slightly domed . I've never really noticed it , but it's been a while since I lapped a new hone .

If you want to get rid of the doming you may need to create a flat spot in the centre first or you will tend to ride the current shape. Try turning the stone 90º to the DNT till the centre is flat then turn round again & be sure not to rock the stone off the new true spot.. Keep your pressure light but on the flattened centre.

Have you got a belt sander? That's the fan favorite among woodworkers to get arkansas stones close before going to something more precise.

Just make sure if you do, that you absolutely do the work outside

Try a fresh new concrete block if you don't have a belt sander.

question the translucent is this a new stone ?

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Originally Posted by eleblu05

question the translucent is this a new stone ?

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yes right out of the wrapper. i got 2 of them both are domed the larger one is nearing flat and the smaller one is abough 50% compleat.

Who makes the stone that you're having to flatten? Halls?

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Originally Posted by DaveW

Who makes the stone that you're having to flatten? Halls?

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the thing is that i have stones from a lot of different people some are old and were lapped by the seller others (the arkanasa) were new in the box old , stock for sure got them at a hardware stone that folding.just a paper box . with genuine arkansas stone written on it. all of the rocks i have bought in the last year have been domed to one degree or another.the arkansas not only has the most domeing but its well hard as a rock