Working with MOP

[Sean O'Hare]

Okay I feel that I have a reasonable understanding of drilling holes in Mother of Pearl but am wondering if I can dovetail bolsters with a MOP handle?

I think it was Warren Osborne who said never to dovetail bolsters with Mammoth Ivory, I am wondering if the same issue exists with MOP, ie. that the scales can/will move?

Any opinions are appreciated.

Sean

[John R. Fraps]

Mother of Pearl is much more stable and less affected by changes in temperature or humidity than bone or ivory or even antler. But as you found on that thread about drilling MOP, it sure can chip easily when cut or drilled or is hit or dropped.

It can be dovetailed but I would not use a dovetail cutter...if you want to dovetail MOP, sand the pearl.

Beware that if you dovetail, you are creating a potentially real sharp edge on the bolster so fitting and finishing is not just for looking good, it also is for safety.

Personally, I would rather not dovetail MOP but it can be done by belt or disc sanding.

[Sean O'Hare]

Thanks for the reply John. If I did dovetail it I would use my grinder to do it, it's the only way I have available to me. As this is my first time working with mother of pearl I think I will keep it as simple as possible and not dovetail it.

Thanks for your opinion.

Sean

[John R. Fraps]

Sean,
I am not the top "expert" re MOP. I have certainly paid dearly when not fitting it right. I think you decision is a good one......concentrate on the fit and finish at the bolster/pearl fit. 90 degreess to 90 degrees.

If you were to choose to do a single bolster knife this time (barehead), it is easier, not easy but easier, to fit it up. ...

Here are some additional resources:

http://boseknives.com/backpocket-construction/

http://boseknives.com/pvtbushing/

Saying these are additional resourses is kinda like saying...something so significant that you ought to see them.......and then some!

[Sean O'Hare]

Hey thanks very much for those links! I had not seen those before. They both look very informative.

Thanks again.

Sean

[Charlie Mathews]

What happens when you dovetail bolsters with mammoth ivory? Are you talking about bolsters on each end of the handle as you might have on a folder? Does this ivory behave differently from elephant ivory or other exotic materials.

[Warren Osborne]

I dont dovetail any ivory modern or ancient. The problem lies in the ivopry expanding & contracting with the change in climate . Ive seen & have had ivory actually lift the bolster off a knife. A dovetail traps the ivory where it cannot move . If the bolster is not joined to the liner with pins or hard solder it can lift the bolster away from the liner.
Pearl is very stable & no such thing takes place. The dovetail joint looks better & for me no more difficult to fit well than the straight . Both need to be flush.

Warren

[Charlie Mathews]

Thanks for the information. We use 1/8 inch stainless pins (at least two but mostly three) that we peen in place and have not had a problem. One point that has not escaped us is the fact that it is very humid in South Georgia. That may be the reason we have experienced no problem to date. We have not sent any ivory out west and dread the day we get that request. I just checked the knife I had with me this summer, I used it for one of my knives that was judged for my voting status, and the ivory is just as I finished it. There is absolutely no movement. We always thought mammoth ivory was very stable (that's the reason I followed up on this). Maybe it is our humidity.

[srj]

Harry,
Send a knife out west and it, the ivory will shrink, so a dovetail probably wouldn't be a problem in that specific situation, though a gap may appear. But... Warren is right, you'll be safer not dovetailing. (You've been warned, as they say, I've seen the same thing with bolsters actually being lifted off of the tang, or liner.......)
Ivory, or pretty much any natural handle material will swell/expand when exposed to high humidity and shrink when humidity is low. I can send a knife just about anywhere (Except Phoenix!) and it won't shrink too badly, but send me a knife that was made in GA, or FL, or LA, etc. and the natural handle material will shrink up somewhat.