Ceramic Vent liner's

[12ptdroptine]

Has anyone ever thought about ceramic coating the hole's in a vent liner? My aunt used to do ceramic stuff and has her own kiln. I was just wondering how that would hold up on the inside of a vent liner. Those ceramic tile's on the shuttle hold up pretty good ya know. Drop

[FLETCH]

I think that there were some traditional vent liners that were make with a platinum insert at one time and they reportedly lasted a long time.

[youp50]

I would venture a guess that it is purely an economic thing. It goes something like this.

A friend of mine worked at a major construction equipment manufacturer in the mid 1960's. They put two machines on jobs with forged track pads. They lasted many years longer than the cast steel pads. That is not really a good thing for the sale of replacement pads. Ergo no more forged pads.

For an aftermarket company to get involved with the design, set up and manufacture of ceramic inserts or ceramic lined vent liners would make them rather spendy. If you consider that a factory vent liner is several bucks and last an average ML 10 shooter an arguable three years at 10 shots per year and 30 shots per liner, there really is no market.

There are board members that will set up a new breech for you with hardened drill bushings with very long life spans.

There are board members that drill their own vent liners. I am soon to be among them. Depending on my ability to avoid flexing the carbide drill bit I should be in the range of 30 cents per bushing with no labor cost.

It is a good idea. Ideas also need to be cost effective.

[dave d.]

:)our own edge made some but i don't remember what the outcome was.

[12ptdroptine]

Jan 13, 2009 11:06:52 GMT -5 youp50 said:

I would venture a guess that it is purely an economic thing. It goes something like this.

A friend of mine worked at a major construction equipment manufacturer in the mid 1960's. They put two machines on jobs with forged track pads. They lasted many years longer than the cast steel pads. That is not really a good thing for the sale of replacement pads. Ergo no more forged pads.

For an aftermarket company to get involved with the design, set up and manufacture of ceramic inserts or ceramic lined vent liners would make them rather spendy. If you consider that a factory vent liner is several bucks and last an average ML 10 shooter an arguable three years at 10 shots per year and 30 shots per liner, there really is no market.

There are board members that will set up a new breech for you with hardened drill bushings with very long life spans.

There are board members that drill their own vent liners. I am soon to be among them. Depending on my ability to avoid flexing the carbide drill bit I should be in the range of 30 cents per bushing with no labor cost.

It is a good idea. Ideas also need to be cost effective.

Not an insert..But like the ceramic glaze we used to put on the item's we were making..then fire it in the kiln.. It was applied with a small paint brush ..then allowed to dry and then put in the kiln and fired.. I was thinking of something like that paint it in let it dry then run a jewler's drill bit gently through it for size then fire it with a torch... Just an idea. Drop

[DW]

IIRC Edge had a plug with a ceramic bushing enclosed in some type of metal sleeve that was pressed into a modified plug. I think wear was non-existent but there was the worry of the bushing cracking.
Maybe Edge will revisit this once he has time to breathe after the switch to the new board.

[petev]

Jan 13, 2009 19:42:29 GMT -5 DW said:

IIRC I think wear was non-existent but there was the worry of the bushing cracking.

Those two considerations have always been true for ceramics for better and worse, as far as I've ever heard. But, drop, ceramics do seem like a natural for the vent liner, given that the high temperature is the main problem with the vl.

[DW]

At one time I believe someone had some Inconel(spelling?) screws that they made into ventliners, supposedly had a ridiculous amount of shots with no wear. Pete and I talked about using this material for his bushings in his plugs, not sure if he looked into it any further.

[edge]

I have used ceramic vent bushings in the past. I sent one to RB and also SW.

To my knowledge they never wore out.
They were a high alumina ceramic material. One style had 2 0.024 diameter holes.

The risk was that the web between the two holes would break and then you would have one large hole. The material also needed to be machined with diamond tooling

IMO, your greatest risk is that the ceramic material may chip off, but it sounds like a very interesting project if you have access to the kiln:)

IMO, a worn out vent liner with the ID coated with glaze and fired might last a very long time with very low risk.

edge.

[SW]

:)1 for sure never wore out.

[jims]

I have two vent liners that were coated with some type of material (potentially ceramic). I think it was called MIST. Something to do with molecular technology depositing. I have not had a chance to shoot them to see how long they will last, I was told the material is very hard and thin but can be scratched and if that is done then the film will be damaged.

[12ptdroptine]

OK so if ceramic coating wont work .,,, How about cryogenic treating them? I wonder if that would help?

[jims]

To 12ptdroptine: I think the cold treating process does not really add any coating or thickness at all, it is as I understand a cold treat, in effect is the opposite of a heat treat, but serving the same purpose of making the material tougher or more wear resistant. If that indeed is the case it might well work.
I have had it done to a number of my barrels but not the ventliners.

[edge]

I think that it would work as long as it were thin!

edge.