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I've finally joined the world of using a buffer to polish the finish on my instruments. Today, I raked the wheels for the first time (explosion of cotton fluff) and then tried to charge one wheel with Menzerna P204 medium compound (the rust-colored one) after first running the wheel against a board to warm the wheel as Dan Erelwine does in one of his videos. I got zero transfer to the wheel even after holding the Menzerna against the wheel for 20-30 seconds. Nada. Tried several times and got a tiny tiny bit of transfer, but not remotely like what it should be. The bare buffer wheel is basically polishing the end of the Menzerna block. In the videos I've watched, people hold it against the wheel for a just a couple seconds and you can see the color of the surface of the wheel change. My wheel remains almost as white as the new driven snow. I bought the Menzerna a couple months ago so it's fresh, if that's a thing with this stuff. I broke the block in half and tried using the newly exposed surface and got the same result, no transfer.

Any ideas for what's going on here? Is there such a thing as a bad block of Menzerna or am I doing something wrong or not doing something I should be doing? The wheel is a new StewMac Canton cotton wheel. I'm considering ordering a new block of Menzerna but the stuff's not cheap. Thanks for any help.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

why are you using 204 that is for hard coatings
I use these
175 for final
https://www.menzerna.com/products/solid ... ing-steps/
this link I use medium and finish
what you have isn't for guitar finish not all menzerna is for wood some are metal comounds
here is what 204 is for
https://www.menzerna.com/products/solid ... -cut/p204/

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I start with the P204. Sounds like your wheel is too soft. A medium cotton airway wheel is needed for this compound. It would not load on a soft dommett wheel very well.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

I start with 204 also. What temp is the room and compound?

Along with Brian's comment, it takes quite a bit of work to really break in a new buff. Raking is a place to start, but trimming the buffing surface with sharp scissors so that it is flat and free of stragglers is important. Rake, trim, charge, buff, repeat. The wheels get better over time.

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It will probably be alright.

Here's a link to the buffs Brian described.

https://www.jescarguitar.com/shop/jesca ... 60-cotton/

Thanks for all the replies.

John - I'm using P204 because I'm using the method of another builder whose finishes are super nice. I didn't want to try to reinvent the wheel. Also, LMI sells P204 for this purpose.

Brian - The wheel I've been trying to load is a Canton wheel, not a Domet wheel. I'm using the Canton wheel for the P204 because that's what StewMac recommends using for medium compound. I do have a Domet wheel for the fine compound. I got both from StewMac. The wheels came unlabeled so I'm deciding which is which based on the photos on their website:




Glen - I was wondering last night if temperature could be a factor. The shop was about 64 degrees and the compound had been stored there. I brought the compound into the house last night and I'm heating the shop this morning to see if that makes any difference. The Menzerna website says it should be stored between 15 and 25 degrees C (59 and 77 degrees F) so it seems like that shouldn't be the problem?

Greg - I raked until the the faces of the wheels were flat and the fluff explosion had died down. I don't know though if that was enough though. I did go over them with a pair of scissors and removed threads and bits that were sticking out.

Michael - Thanks for the link.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

+4 Brian's comments. Domet for medium, Canton for fine.

Just for fun, I recently redid my buffer, which I posted previously.
Note: I made a new cover, taking off the corners and playing with joints.

I'm confused. Brian says above to not use a Domet for medium.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

I had the same experience when I started with buffing wheels and Menzerna. I could get the medium to take a bit of compound enough that you can see the colour change on the Canton but found it almost impossible to get the fine to take on a soft wheel. I persevered but stopped to add what compound I could get on as often as I could. It took me all day and half of the next to buff the first time I use'd them.

I have found like Greg suggest's that they work better the more you use them. I haven't changed anything with my set up. Still got the same blocks which are now 4 years old, same wheels. After a few guitars I found the wheels would take the compound just like in the videos and i can buff a guitar out in a couple of hours.

Maybe try raking the wheel again, do the Erelwine trick, try adding some compound, buff the board as if it's the guitar, rake again etc. Might help break the wheel in.

I use canton for medium and Domet for fine.

Good luck.
Glenn.

I just checked Jescar, StewMac (and Grizzly from memory), seems different companies interchange the names for different buffs, causing confusion.

Basically, use the "harder" buffing wheel for medium, and the "softer" buffing wheel for the fine. If you look at the StewMac image you posted, the Canton is the soft, and the domet is the hard. Jescar calls it different.

Actually when I match up the wheels I have with those StewMac photos and check them by hand, the one that's labeled Domet is definitely the softer one. The individual sheet/disks in that wheel have a finer, tighter weave and the texture is a bit like very thin felt. The individual sheet/disks of the Canton wheel have a coarser weave and are rougher and a bit thicker and stiffer.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Happy days! Problem solved. I had tensioned the drive belt based on what I saw in a few videos. In those, the belt was loose enough that pressing hard against the wheel would slow it down a lot, even to a near stop. I had mine set loose enough that pressing hard slowed the wheel some, but it wasn't loose enough to be able to make it slow to a crawl. Turns out that it was slowing down enough though that there must not have been enough friction/heat to pick up compound off the block. Buffing is on the agenda for this evening.

Thanks to everyone for their suggestions and experiences with their buffers. It's much appreciated.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

First time buffing an instrument with a buffer. So far so good. I did the body of this octave mandotar this evening and it didn't get smashed to kindling. There's some room for improvement, but I can already see what a step up this is from going through the Micro Mesh series by hand. Also much faster a whole lot less tedious.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Nice job there. Glad you got it all rolling!

I had the same issue early on when I tried to tension the belt to act as a slip clutch. That may be a good tip for fast, aggressive setups with lots of power and no room for error. But the Stew Mac system is very forgiving and requires full belt tension to drive the buffs enough to get the work done. Glad you figured it out, power buffing is the way to go.

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It will probably be alright.

I currently run a 3 stage buff out on UV Poly as follows with the equipment used listed. All compounds are Menzerna

Level sanded. finished lightly by hand at 400. Pre polish with 113GZ on a Airway construction, 60/60 Cotton buff.

Inspected and defects sanded at 600 and rubbed with light grey scotchbrite. Polish with P204 on a different Airway construction, 60/60 Cotton buff.

Followed with GW16 on a Airway construction, super-soft Bleached Domet Flannel buff.

For clear finishes with a clear pore fill this is where I stop. Solid colors will get an additional pass with Atol6 on a Airway construction, super-soft Bleached Domet Flannel buff.

So which buff is which? Look at the sides of the wheel. The flannel will be a soft material just like a flannel shirt or pajamas. The 60/60 will be a bit coarser and stiffer, closer to denim than flannel. Breaking in a new wheel takes about an hour. I find a nice split of hardwood firewood like oak to be the most efficient tool. To break it in I rake the wheel for about 2-3 minutes and then start buffing the split oak. You want to really work it, almost stall the buffer at points. I pause to trim the "whips" as needed. The idea is to soften up the buff and fray out the edges. When the wheel without compound can gloss up rough oak fairly quickly you are ready for final prep and compound loading. So again rake the wheel real good to remove any splinters. Trim the surface of the wheel so there are no whips or hard tufts. Now load the wheel with the desired compound and work it with a smooth piece of softwood, I use a pine 2X4 scrap. Repeat this last step of applying compound and buffing the 2X until the wheel colors up on the outside quickly (20 seconds or so) and you are ready to buff.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Brian - Thanks a lot for writing up this detailed description, especially the part about prepping the wheels. I searched for that kind of information, but had no luck. I definitely need to put in more prep time on my wheels. Once you have the wheels prepped, if you take a close look at the edges of the individual cloth disks in a wheel, about how long do the frayed ends stick out past the woven part of the cloth? About 1/4", 1/2", 3/4"?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Good on you Jay. I am still toiling away with micromesh and keep looking at those buffing wheels...

Dave M

Per Brian's method for prepping the buffing wheels, I went back and did a bunch more raking this afternoon. Guess what the shop looks like.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

The 60/60 wheels fray out about 3/8"- 1/2".The compound used will help set that in the end after you load and use a bit. The coarser rouge like 113GZ loads up on the fibres more so the frays are deeper than the P204. The softer flannel wheels only about 1/4".

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

This is the dirtiest job in the entire shop hands down.....

Another point on breaking in buffs. There are two things you must accomplish. 1; fray the ends so they take compound. 2; soften the buffs so they conform to the surface during use and develop a good footprint.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Super good info in here.

Jay, I see you have the buffer wheel covers like Michael but I can't tell if you've hooked them to dust collection or not? Do you plan to?

As Brian mentioned, it makes a mess. I'm considering making the dust hoods but a little intimidated.

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Thanks again for the good information. Like I said above, I had no luck finding this kind of info on buffer wheel prep on the web so it's much appreciated.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

They are set up for dust collection, but unlike Michael, I don't have a shop-wide dust collection system so mine can be connected to my shop vac through ports on the back at bench height. I'm not convinced that it does as much as I hoped though because the shop vac just doesn't pull as much air. Also, from my initial experience using the buffer, I think a large part of what gets thrown off the buffer wheels goes to the floor below them and doesn't get as far around as the dust port.

I am convinced that it was worth building the hoods though because they do prevent the buffer wheels from slinging buffing compound particles and dust all over the place. There's also a safety factor to not having two large spinning wheels fully exposed.

Michael and I used different methods to build our hoods. If you are interested, I could add a few photos showing how mine went together on that thread you started on dust collection from buffers. https://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=51310&hilit=buffer

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter