[alex_ku]

By volume.
As for Alex, if you think about it, the physical properties of natural granite (and diabase) are a function of its makeup - quartz, feldspar and mica. If we introduce plastic (epoxy) in any large quantities, we greatly compromise why we are choosing granite - 8% by volume has been shown to yield as close to natural stone as possible
The epoxy acts as a bonding agent and only a bonding agent. The aggregate is sized and shaped so intimate contact is insured between the aggregate particles themselves - the epoxy filling only the voids.

I agree with you, but also have my own opinion
All that you say is appliable only if you use right mix of sands. If you have some disbalance (for example low quantity of micro size sand), in case of hobby its possible, than youll get voids, because of small amount of epoxy, and final result will have poor quality.
But if you add more epoxy and use vibration - all corns will fit together with minimum distance between each others and extra epoxy will be on the top of form, where you can remove it. All what i say is based on my own experiments.

PS: sorry foy my poor english.

[alex_ku]

hi all!

I need some help:
meybe some one know links to seller/manufacturer (in EU) of insert nuts applicable for epoxygranite ?
I had one but lost link and cant find it any more

Thanks!

[jonixllc]

hi all!

I need some help:
meybe some one know links to seller/manufacturer (in EU) of insert nuts applicable for epoxygranite ?
I had one but lost link and cant find it any more

Thanks!

Contact: [email protected]
It is located in the midlands, specifically the Leicester area
They used to be the main supplier of epoxy granite bases for Taylor Hobson metrology products as well as Taylor Hobson's line of ultra precision machine tools
Derek Robinson used to be the Managing Director and has good experience in epoxy granite
If they cannot provide you with an EU manufacturer, I can give you a US manufacturer

[alex_ku]

meybe some one know links to seller/manufacturer (in EU) of insert nuts applicable for epoxygranite ?

I found it! Maybe this help to someone: http://www.rampa.de

[ckelloug]

Alex,

The RAMPA stuff looks more appropriate to wood to me. Any second opinions?

Jonixllc,

Thanks for the reference to rock of ages. I've got a big surplus solid granite plate made by them but I didn't realize they also did E/G.

Regards all,

Cameron

[jonixllc]

Alex,

The RAMPA stuff looks more appropriate to wood to me. Any second opinions?

Jonixllc,

Thanks for the reference to rock of ages. I've got a big surplus solid granite plate made by them but I didn't realize they also did E/G.

Regards all,

Cameron

Rock of Ages DO NOT do E/G - they do have inserts

These inserts are not for granite or epoxy granite
An insert for granite or epoxy granite is essentially a solid round of steel or stainless steel with essentially a circumferential set of milled grooves and a vertical set of milled grooves. The insert is sized like the following: An M10 threaded insert would have an OD of 19mm - so multiply the OD od the thread X2 to get the OD of the insert
The hole that the insert goes into should have no more than 0.13mm radial clearance - this keeps the epoxy bond layer thin and strong

[alex_ku]

well, seems like you rigth guys.
so, i'll use something like this.
it cheap and strong enought.

[brunog]

Alex,

The RAMPA stuff looks more appropriate to wood to me. Any second opinions?

Cameron,
Actually the dowel nuts with the large heads could be of some interest however I personally prefer using threaded rod couppling nuts available just about anywhere and combining them to a flat washer and short hex bolt at one end. (as per Alex Ku's earlier post)

BTW Cameron, nice work! I still check the thread about once or twice a week, I am busy doing renovations these days including a 15' x 25' workshop in the basement for future projects(includung EG)

Best regards

Bruno

[Eric R.]

hi all!

I need some help:
meybe some one know links to seller/manufacturer (in EU) of insert nuts applicable for epoxygranite ?
I had one but lost link and cant find it any more

Thanks!

There are two main methods to apply inserts:

Method 1) NOT RECOMMENDED! First cast the E/G and after curing drill holes and place the inserts. This has some major drawbacks: (a) drilling holes in a cured products may not be very accurate and (b) it may damage the E/G. Also, after you have drilled the holes, you need to apply the inserts by either pressing them into place (which is more appropriate for wood and plastics) or by glueing them.

Method 2) RECOMMENDED! Imo a much better option is to pre-mount them in your mold and then cast the E/G. For this you will need inserts that have been developed for casting purposes, as where most inserts (including those from rampa.de) are for wood or other soft materials and which are applied by drilling/screwing and/or pressing (method 1). Here is a manufacturer that has a nice collection of inserts for casting purposes: www.anchorinserts.co.uk.

The image below is an example of a blind (one side is closed) insert and its cross-section.



Regards,

Eric

[jonixllc]

I agree with you, but also have my own opinion
All that you say is appliable only if you use right mix of sands. If you have some disbalance (for example low quantity of micro size sand), in case of hobby its possible, than youll get voids, because of small amount of epoxy, and final result will have poor quality.
But if you add more epoxy and use vibration - all corns will fit together with minimum distance between each others and extra epoxy will be on the top of form, where you can remove it. All what i say is based on my own experiments.

PS: sorry foy my poor english.

Alex-

Your english is OK
You are correct - the correct size of aggregate is of high importance
For most manufacturers, this is what is proprietary in their process
For most ultra precision applications, achieving a base that's as close to natural granite is the goal -strength, mechanical and thermal stability and good damping characteristics
Although epoxy granite has its limitations, manufacturerd properly it also has its advantages