Switching Macap M4 from stepped to stepless - DONE!

Grinders are one of the keys to exceptional espresso. Discuss them here.
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#1: Post by dorkboy »

So when I bought my Macap M4 about 1.5 years ago, stepless wasn't around yet. Then about 6 months later, there they are. So I have never been able to find that perfect step, always one or the other, but not perfect. So about a month ago, I started emailing everybody out there about buying the stepless setup and putting it on my machine. Most people said that it can't be done, and you will ruin your machine by doing so plus they wouldn't sell it too me.
So Chris from Chris' coffee sold me the complete setup for like $30. And for $30, if it works, great, if not, well it's only $30.

After 45 minutes, it is installed and working perfectly! my grinder was already designed for it but just 2 holes had to be drilled in the body.
If you want to know if you can do yours, 1st remove the 3 #1 phillips screws from the base. Look inside, there should be 5 tabs to screw into, 3 are used to hold the motor/grinder to the body from the top. The other 2 that are in the back between the main screw is what you screw the stepless too. I would say, even if you don't have those 2 stepless holes, you could drill/tap holes, that was my original plan. The body is about 1/4" thick, and that's plenty to hold.

I could probably do it again in about 15 minutes.

So for everybody saying that it can't be done. It can and without problems.



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#2: Post by TruthBrew »

Has anyone else attempted this? Looking for more details as I am a stepped M4 owner.

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#3: Post by TruthBrew »

For the record, this conversion is quite simple for anyone with basic mechanical skills and some tools. $38 in parts plus 45 minutes and I'm done. Pics soon.

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#4: Post by HB »

Thanks for the update and the (upcoming) photos. :)
Dan Kehn

da gino
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#5: Post by da gino »

I agree that this is well worth knowing, when I bought my stepless I'd noticed that the stepped was available in chrome for $499 through Amazon (it was actually Espresso Parts NW, through Amazon, but I couldn't find it directly on their website), while for the stepless the vendors I trusted such as EPNW, Chris' etc had the chrome listed for $629. I am sure that many people would gladly save almost $100 for a little work especially if there is a good photo guide up on this thread. Thanks!

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#6: Post by TruthBrew »

Not perfect instructions, but here is what I did. Thanks also to the original poster Scott (aka dorkboy) for additional information and my neighbor Jeron for the tools and drilling.

NOTE: All work should be done with the grinder unplugged! Since there may be variability in parts and grinders, be sure to double check everything listed on here yourself beforehand. This mod will likely void any warranty you may have.

There are two possible conversions based on when your Macap M4 was manufactured. To check which you'll need to use, turn the empty grinder over and remove the 3 outer screws holding the bottom panel to the base. Look all of the way into the body to see how the motor is mounted to the body. There will either be 3 mount points (like mine) or 5 mount points (like the original poster's).

If you only have the 3 mount points, you will need to drill and tap holes to mount the worm gear to. If you have 5 mount points (only three are used, the other two are open), you should only need to drill holes in the case so that you can screw the worm gear into the unused mount points.

The "3 mount point" (older revisions) conversion:

Tools used:
- Drill
- #21 drill bit [needs to be verified, didn't write down at time of work]
- #10-32 tap [needs to be verified, didn't write down at time of work]
- thread oil (optional)
- small punch (we used a transfer punch as well as a center punch)
- hammer
- small hex key (allen wrench) <need to check size and update post>
- small Phillips head screwdriver

1) Order from Chris' Coffee the Macap M4 stepless "conversion", which is ~$38 and includes:
1 x plastic toothed neck ring
1 x worm gear assembly which includes worm gear, 2 thumb screw covers and 2 screws

2) On the grinder neck, remove the 3 Philips screws holding the plastic neck ring to the upper burr assembly.

3) Remove the upper burr assembly by depressing the button and unscrewing it all of the way.

4) Remove the spring loaded "step lock" button (no longer used)

5) Replace the upper burr assembly. Just give it a few turns, no need to screw it in completely as we'll remove it again.

6) Place the new plastic toothed neck ring on the upper burr assembly, make sure it locks in place with the plastic tabs but no need to screw in yet.

7) Place the worm gear on the back center of the grinder body so that it matches up with the teeth of the new neck ring. The worm gear base should almost butt up to the inner metal circle. NOTE: The worm gear will completely cover the back body screw.

8 ) Center your drill points as much as possible and mark them with a punch or similar tool. The holes on the worm gear part are oval shaped, so there is some play if you are slighly off.

9) Once marked, remove the worm gear, toothed neck ring, and the upper burr assembly (so it's not damaged during drilling).

10) Using a punch and hammer, carefully punch the marked drill spots so the bit has guide points.

11) [Optional] Turn grinder over and remove 3 screws in base. Carefully pull the base plate out from under the grinder and set the grinder up right so the plate is on the side of the grinder. This is so any metal shavings don't end up in the wiring.

12) Using either a hand-held drill or a drill press and a #21 bit (VERIFY SIZES ON YOUR PARTS), carefully drill the holes into the grinder body taking care that the holes are straight. NOTE: The body is quite thick, nearly 1/4".

13) Use a vacuum, brush, magnet, etc... remove the metal shavings from the grinder.

14) Using a #10-32 tap and some threading oil, carefully tap the holes.

15) Again remove any metal shavings and also check the interior of the grinder body for any metal shavings.

16) Replace the upper burr assembly and the toothed neck ring. Secure the neck ring with the 3 small Philips screws.

17) Place the worm gear onto the grinder body and slide in to interlock with the toothed neck ring. Attach worm gear to body by using included bolts and a hex key to tighten.

18) Attach thumb screw covers to worm gear posts.

19) If you removed the base plate, reattach it now.

Test, dial in your grind, and that is it.

The "5 mount point" (newer revisions) conversion:

NOTE: I did not attempt this method, but the original poster did

You can follow the same basic instructions for the 3 mount point conversion, however you will need to align the drill spots with the existing threaded mounting points on motor body. To give your self some room for adjustments, you should use a larger drill bit than quoted as the thumb screws will hide the holes anyway.

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#7: Post by Alan »

Resurrecting an old thread because I'd like to do the same thing...

I also have a stepped Macap M4 that I'd like to convert, but I just emailed Chris and he said he'd never sold conversion parts and doesn't have any at this time either. Are you sure you got them from him?

Anyone know of another source that might sell them? Maybe anyone else who sells the stepless M4 and could get parts?

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#8: Post by TruthBrew »

Sorry for the late, late reply, but yes I absolutely got the parts from ChrisCoffee... might want to check with Mary or Roger, assuming they are all still there.

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#9: Post by naked_barista »

You might also try 1st Line. I got a replacement worm gear assembly there when one of my thumb screw covers broke. I don't know if he has the neck ring or not, and the screws to mount it are probably available at the hardware store.

larry at laurelnet dot com

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#10: Post by kitt »

1st line had the adjustment mechanism (worm drive) on special the other day when i checked - down from $39 to $29 i think.Unfortunately i'm in New Zealand and they don't post internationally.Stefanos' espressocare site has them and posts internationally, but it's $65 on there, just a bit too much for me! I couldn't find it on the chris coffee website, if someone can confirm they do have it please let me know.