OLD MATE (formerly Medgrind)

OMD

Well-Known Member
Accessory Maker
Question for @OMD: if the OG as shipped can’t be immersed in ISO for cleaning, what are your recommendations for cleaning? Do you recommend switching to a ceramic bearing for this reason?

The other two “upgrades” seem unnecessary to me.
I have had customers remove the top seal from the bearing and submerge in iso to clean. Just be aware, there is a chance of the balls in the bearing flash rusting if you let them get dry for too long without some kind of oil on them. I recommend putting a drop of avocado, olive, veg oil in the bearing etc as its food safe. I personally would just dab some iso drenched Qtip around the lid to clean it when the time comes.
 

OMD

Well-Known Member
Accessory Maker
He says to remove the bearing if you ever need to deep clean the unit.
If I could not work out how to remove the bearing I would simply use iso in a shallow dish with the teeth facing down so the iso level stays below the bearing for a good long soak if I did not own an ultrasonic cleaner or a ceramic bearing.
Ceramic bearings have a habit of breaking during installation compared to steel so that may be part of the reason along with wanting the magnetism would be the reason for the standard issue jobs. That said, Ben would happily install any bearing you like when made.
I have purchased some ceramic bearings just now to test out. Thankyou for taking the risk and trying them in your grinder!

As part of me being open and honest with you all i need to share that i I have had some concerns from people regarding the bearing sliding on and off the post potentially causing metal dust. To alleviate any concerns i would like to offer ceramic bearings on my website.

I obviously need to test them out to make sure they dont break on install (might mean i need to hold a super dooper tight tolerance on the lid bearing pocket) and are fit for purpose.

Super keen to hear you guys thoughts on this?
 
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jbm

Well-Known Member
As part of me being open and honest with you all i need to share that i I have had some concerns from people regarding the the bearing sliding on and off the post potentially causing metal dust. To alleviate any concerns i would like to offer ceramic bearings on my website.
I can’t determine from this whether you think this is an actual possibility or not. Should we be replacing the bearings after all?
 
jbm,
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LesPlenty

Well-Known Member
Company Rep
To alleviate any concerns i would like to offer ceramic bearings on my website.
The minute amounts of black dust accumulate on the white ceramic bearing as well (probably worse but not sure as ceramics can be about 3x harder than S/S) and is also more noticeable than with s/s raced bearings due to the ceramics being white.
The ceramics only break if you do not have them lined up correctly when installing, the ceramics are unforgiving compared to steel and will not tolerate an uneven press.
 
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OMD

Well-Known Member
Accessory Maker
I can’t determine from this whether you think this is an actual possibility or not. Should we be replacing the bearings after all?
I personally don't see this as a massive concern, the amount of residue is probably 0.1% compared to the safe limits of metal exposure. You would probably need to inhale the entire post to be a concern. Metal fabricators/ welders etc that are grinding/filing all day might be a different story.

However my opinion is irrelevant!! If my customers have concerns i will do everything i can to help. I want you guys to be able to do whatever you like with your grinders. If you want to change the bearing then you should be able to imo. I created them using skateboard bearings so you can change them and make them your own.

The black dust accumulates on the white ceramic bearing as well (probably worse as ceramics are about 3x harder than S/S) and is also more noticeable than with s/s raced bearings due to the ceramics being white.
The ceramics only break if you do not have them lined up correctly when installing, the ceramics are unforgiving compared to steel and will not tolerate an uneven press.

I believe the new filleted post design should help with this as there is a lot less contact area, however its something i need to test!
Do you mind sharing a photo of your inner race on your ceramic bearing?

Maybe pressing in a post of a different material will 100% eliminate this issue.
 

LesPlenty

Well-Known Member
Company Rep
The dark lines do not disappear completely once q-tipped so both surfaces seem to be wearing.
If this sort of thing concerns you a simple drop of cooking oil on your finger wiped over the top post occasionally may stop the wear?
1681387510187-jpg.45633
 

OMD

Well-Known Member
Accessory Maker
The dark lines do not disappear completely once q-tipped so both surfaces seem to be wearing.
If this sort of thing concerns you a simple drop of cooking oil on your finger wiped over the top post occasionally may stop the wear?
1681387510187-jpg.45633
Excellent photo! Thankyou.

Alrighty, I think any bearing would be fine if it was in conjunction with a post with a pressed in PEEK top section https://en.wikipedia.org/wiki/Polyether_ether_ketone would be absolutely ideal.

We machine peek for a lot of high demanding applications and it's quite awesome stuff! I know it would work well because its self lubricating and i have used it as a dry slide for a nickel plated aluminium bush to run it. It blew my mind how well it worked.

Thoughts on this?


EDIT:
Something like this is what im thinking.

 
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Knewt

Well-Known Member
Excellent photo! Thankyou.

Alrighty, I think any bearing would be fine if it was in conjunction with a post with a pressed in PEEK top section https://en.wikipedia.org/wiki/Polyether_ether_ketone would be absolutely ideal.

We machine peek for a lot of high demanding applications and it's quite awesome stuff! I know it would work well because its self lubricating and i have used it as a dry slide for a nickel plated aluminium bush to run it. It blew my mind how well it worked.

Thoughts on this?


EDIT:
This is what im thinking.

I think this is a great idea. Personally, I feel you are addressing possible wear issues better than any of the other grinders that I have seen discussed.
 

OMD

Well-Known Member
Accessory Maker
I think this is a great idea. Personally, I feel you are addressing possible wear issues better than any of the other grinders that I have seen discussed.
Thankyou! I appreciate that. Instead of letting this get me down i will tackle it head on and make this product even better.


Also guys, they make PEEK bearings. (that's how good the stuff is)

PEEK BEARING

This could be offered as a retrofit if you guys have any concerns with your current aroma-3?

11pm here. I need to get some sleep. Feel free to add any input guys

Thankyou!
 

jbm

Well-Known Member
This could be offered as a retrofit if you guys have any concerns with your current aroma-3?
How would these differ from the OG bearings or the ceramic bearings wrt performance and cleaning?
 
jbm,

Timps27

Feel like I’m winnin’ when I’m losin’ again
Impatiently awaiting my current revision A3, I don’t think I would want to retrofit it, but I would almost certainly add a PEEK version to the collection!
 

minasch

Well-Known Member
He says to remove the bearing if you ever need to deep clean the unit.
If I could not work out how to remove the bearing I would simply use iso in a shallow dish with the teeth facing down so the iso level stays below the bearing for a good long soak if I did not own an ultrasonic cleaner or a ceramic bearing.
Ceramic bearings have a habit of breaking during installation compared to steel so that may be part of the reason along with wanting the magnetism would be the reason for the standard issue jobs. That said, Ben would happily install any bearing you like when made.
Interesting, how do you use an ultrasonic cleaner with a grinder?
 

lapis

Well-Known Member
This could be offered as a retrofit if you guys have any concerns with your current aroma-3?
I applaud your efforts to make this grinder create as close to zero metal dust as possible, but I'm personally totally unconcerned about the absolutely minuscule amount of metal dust created by the bearing sliding onto and off of the post – and it's worth noting that a ceramic bearing could even create more dust than a metal bearing, due to, as mentioned by @LesPlenty, the fact that ceramic is a significantly harder material than SS.
 

minasch

Well-Known Member
Beakers of iso suspended in the water bath (I also put a plastic lid over while cleaning),
img_20190604_170322-jpg.9785

There is a grinder in here with what was fresh iso at the start,
img_20181209_162928-jpg.6473
Wow, impressive cleaning setup. The ultrasonic cleaner looks like a professional one?
I figured already that you would need quite some equipment to put a grinder in iso into an ultrasonic cleaner. I cleaned my Dynavap parts in the past in an ultrasonic cleaner for glasses. That was a lot easier cause you could just use bags. I was very impressed how much more residue from the dynavap tip the ultrasonic cleaner was able to remove compared to an iso soak.
 

Shit Snacks

Milaana. Lana. LANA. LANAAAA! (TM2/TP80/BAK/FW9)
I have had customers remove the top seal from the bearing and submerge in iso to clean. Just be aware, there is a chance of the balls in the bearing flash rusting if you let them get dry for too long without some kind of oil on them. I recommend putting a drop of avocado, olive, veg oil in the bearing etc as its food safe. I personally would just dab some iso drenched Qtip around the lid to clean it when the time comes.

Oh, I had no idea lubricating the bearings was a thing we would have to do at all until now... Not thrilled about the idea, I'm also not exactly sure where the lubrication should be going? It is all sealed up in there I wouldn't really feel comfortable just smearing oil all over personally... Like I'm someone who's always washing my hands from oils, I don't like lotions etc, I wouldn't really want loose oil around somewhere like that where I'll end up touching it and then feeling like I need to wash my hands?

I have purchased some ceramic bearings just now to test out. Thankyou for taking the risk and trying them in your grinder!

As part of me being open and honest with you all i need to share that i I have had some concerns from people regarding the bearing sliding on and off the post potentially causing metal dust. To alleviate any concerns i would like to offer ceramic bearings on my website.

I obviously need to test them out to make sure they dont break on install (might mean i need to hold a super dooper tight tolerance on the lid bearing pocket) and are fit for purpose.

Super keen to hear you guys thoughts on this?

Yes this is one of the things I was waiting for! Hoping you would offer these same ceramic bearings Les discovered, so I wouldn't even have to bother trying to change bearings, and I could get a second OMD from you with it (along with customized finer holed middle plate as I had mentioned previously so it would compliment my current OMD perfectly)

The minute amounts of black dust accumulate on the white ceramic bearing as well (probably worse but not sure as ceramics can be about 3x harder than S/S) and is also more noticeable than with s/s raced bearings due to the ceramics being white.

Oh I had no idea about this dust issue I suppose it is a concern but I didn't notice anything with mine, I do wonder if it would be better with the ceramic and the new post since you don't have that one yet either? Seemed like you wouldn't need it because the ceramics are non-magnetic already but if they are rubbing too much...?

I believe the new filleted post design should help with this as there is a lot less contact area, however its something i need to test!

Yeah I wonder how this improves more of these issues...

Alrighty, I think any bearing would be fine if it was in conjunction with a post with a pressed in PEEK top section

Oooh full peek protection now so my above comments may be irrelevant, more changes, but you could not soak it in alcohol at all if it had this now then?? I don't know tough to clean plastics sometimes even though peek is such high quality?

I trust you'll figure it all out!
 

OMD

Well-Known Member
Accessory Maker
How would these differ from the OG bearings or the ceramic bearings wrt performance and cleaning?

I imagine they would operate the same (ill test this), the plus is that you could submerge in iso /chuck in dishwasher and clean it no problems.

Oh, I had no idea lubricating the bearings was a thing we would have to do at all until now... Not thrilled about the idea, I'm also not exactly sure where the lubrication should be going? It is all sealed up in there I wouldn't really feel comfortable just smearing oil all over personally... Like I'm someone who's always washing my hands from oils, I don't like lotions etc, I wouldn't really want loose oil around somewhere like that where I'll end up touching it and then feeling like I need to wash my hands?
No no no! It's not something you have to do! This only applies if you have submerged your bearing in iso and washed the oil out. it's more of an advanced thing so i haven't really mentioned it for this reason. Sorry i should have been more clear. Some people are comfortable doing this, some aren't. You typically will never need to touch the bearing or service it in these grinders.

Oh I had no idea about this dust issue I suppose it is a concern but I didn't notice anything with mine, I do wonder if it would be better with the ceramic and the new post since you don't have that one yet either? Seemed like you wouldn't need it because the ceramics are non-magnetic already but if they are rubbing too much...?
Not everyone is getting this issue (over 350 out there now and only 3 reports so far). There are a heap of people on my discord showing they don't have this problem.
Oooh full peek protection now so my above comments may be irrelevant, more changes, but you could not soak it in alcohol at all if it had this now then?? I don't know tough to clean plastics sometimes even though peek is such high quality?

The idea is to be able to soak in iso with this peek bearing and it be no problem.
I trust you'll figure it all out!
i will! thanks mate!
 

FNQ2

Member

feralcomprehension

Qualified Observer
Excellent photo! Thankyou.

Alrighty, I think any bearing would be fine if it was in conjunction with a post with a pressed in PEEK top section https://en.wikipedia.org/wiki/Polyether_ether_ketone would be absolutely ideal.

We machine peek for a lot of high demanding applications and it's quite awesome stuff! I know it would work well because its self lubricating and i have used it as a dry slide for a nickel plated aluminium bush to run it. It blew my mind how well it worked.

Thoughts on this?


EDIT:
Something like this is what im thinking.

1. I'm *super* impressed with the energy you devote to responding to your customers.
2. If the addition of PEEK changes whether or not the unit can be cleaned in the dishwasher I would be sad- love that with my Herb Ripper.
3. In the cutaway image the engagement depth of the PEEK post into the ss looks proportionally too short for proper stability and retention.
 

LesPlenty

Well-Known Member
Company Rep
I used it till it became harmonically unbalanced and just to see :)
I ended up just iso q-tipping the tips of the top plate row of teeth that made the smear on the lower part and had been spinning the heck out of my OM and only grinding in smaller amount each time instead of loading up as much as possible in the grinding area. The smear mark disappeared and my bearing was again spinning for over 3 minutes...then I installed my ABEC9 full ceramic and the smear reappeared and just cleaning the opposing teeth has not removed the smear...yet.
 

Cloud McLongFoot

Well-Known Member
Hi guys,
Disappeared from the forum for a while since I got my grinder but decided to come check out the posts. I recently had an issue with my grinder getting stuck after a friend got some herb material caught between the bearing and post before grinding. I used a q tip and iso to clean it and got the a similar black residue off. Could this be from minute amounts fo herb getting stuck?

Too add, after looking at all the new changes and everything I am feeling the temptation to get a second. Will always love my founders edition but that new post and side grooves look nice
 
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Franco

is (most likely) vaping
TBH, I'm starting to be a little concerned about this black dust reports.
I've ordered one exactly three weeks ago, but I haven't received any order/shipping notification yet.
I really hope @OMD comes up with a solution that can be used to retrofit existing units, because at the moment I'm starting to have regrets for this purchase.
 
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