alum oxide vs diamond lapping compound

[bigjake]

Getting ready to do the hardest part for me. lapping/polishing

How much faster does diamond compound work opposed to the other kinds of lapping materials. 220 grit

I have 3 thousands to remove.

thanks

[Red River Rick]

I use aluminum oxide lapping compound for roughing (Clover Leaf / Loctite) brand. Starting off with 220 grit, then 400 grit and finally with 600 grit.
And finishing with 800 and 1000 grit diamond lapping compound.

Being a lot cheaper, the aluminum oxide works just as well for roughing, compared to the diamond.

RRR

[country gent]

Aluminum Oxide, Silicon carbide, diamond are meant for different materials and break down rates. .003 to remove from a mould is .0015 on a side. Normally lapping the initial application is used and as it breaks down becomes finer as it breaks down. I only use diamond compounds for very fine finishes and carbide, a .5 gram tube is around $20.00. Silicon carbide is used for fine finishes a in steels and cast iron, a good tip is start one grit finer than you think you need. I reserve aluminum oxide for roughing.

Once impregnated add only carrier to keep cutting lapping compounds are normally water or oil based carriers you want to know which you have. Work thru a few cycles and add a small drop of water or oil then work some more

[bigjake]

Thanks Rick and Gent :grin:

any other tips from you point die masters are welcomed!

[country gent]

One thing to watch when buying diamond compounds is the concentration of the diamond. Lower concentrations wont cut as cleanly or evenly and much slower. I avoid valve grinding compounds by name as they arnt graded as finely as the true compounds are or they are a blend o several grits, and are usually too coarse.

Another recommendation is to buy yhe dry powder then you can se what ever carrier concentration you desire as needed

[midnight]

I do pretty much as Red River Rick describes using 200, 600, & 1200 Clover which is Aluminum oxide I believe. The 1200 has provided a finish that has been satisfactory to me but I will have to try fine grit diamond to make an even better finish. I have been feeling my way along & trying to get better. One thing I did learn is to be careful & go slow. Using barrel laps, it is suprising how fast lapping compounds cut. It's really hard to put material back on once it's lapped off.

Bob