Official Luthiers Forum!

I know a place who has the Parma rig and they love it. They went out of business recently, and if I had known, I would have offered them money for it. It's really nice...

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I use the StewMac system on my fully assembled guitars with no real problems. I could wish for more space I guess...but since the wheel speed and belt tension don't really grab the instrument out of your hands and fling it I manage without feeling it's a risk. I did mount the system low so I can polish as I sit in a rolling chair. This adds stability compared to standing.

On the shaft concentricity issue...the center hole isn't really fixed perfectly concentrically on any new wheel anyway. New wheels pretty much always require raking to make them spin true so any minor shaft issue is somewhat mitigated by the fact that you have to rake new wheels anyway. I'm not seeing this as an issue unless the shaft is WAY out...but mine seems close to perfect.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

On the website for the Parma unit they have a photo of it without the belt cover; however, the literature states that a stainless steel cover is included.

Have you attempted to contact the manufacturer of the Parma unit?

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Always have plenty of sandpaper; it's rough out there!

Not really.



If you are knocking the guitar on that buffer, it's probably not the machine's fault.

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Aaron Craig

Does anyone have any feedback on the Caswell Rig?

http://www.caswellcanada.ca/shop/produc ... 104&page=1

Cheers,

Richard

It works. Still a bit of a toy though. You'll need to find better buffs than the ones provided. Nice that its small. Ideal for buffing out scratched CDs. When I start doing more shiners again, I'll be going straight past it and the stewmac to the Parma without a second thought. Buffing on the old rinky dinks is a drag.

I have an older (they don't make 'em any more) Grizzly with 1 1/4 " shafts. It has a 2hp motor, direct drive, and a 1200rpm. It is merciless as I have little buffing experience. I just got a Caswell. The cast iron base was broken but they replaced it and were quite nice about it. It runs smoothly. It was recommended by a great repair specialist that you would know as a much better unit than the StewMac one. I have yet to buff a finish with it, but hope it works better.

Danny

OT, but can you point me to a thread that shows how you bolt on a neck with those skinny little sound holes?

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Mike Lindstrom

Being as I'm about to spring for a buffer of some sort, and the StewMac thing looks good to me....I contacted them this week, about the shaft quality mentioned here.
Their reply was this : "We have added pillow block bearings to the shaft which has solved the problems we have had in the past with the previous version. " I'm wondering if this is a true thing.....problem solved?

Any recent experience in regards to this statement.

Michael

No experience with them, but if that's their response then it sounds as if they're stating the bearing quality was the culprit.

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Always have plenty of sandpaper; it's rough out there!

I built mine cuz I'm too cheap to lay out $626.00 for one. I bought a heavy duty portable shaft from Grizzly and the 4 buffing wheels and two grades of Menzerna compound from LMI. I bummed a motor off of a friend, robbed the belt off of my lathe and with some scrap plywood I had laying around the shop I built a stand. All total I have about $160.00 in it. It only runs one pair of buffing wheels at a time but it has no run out or wobble in it.

Their newest style 14" buffer, that I own, has the pillow blocks and steel mounting plate. The shaft on my unit is not straight with a straightedge, the diameter is not consistent as would be a turned/machined shaft and both sides have something different going on so it is out of balance. The only tough to source component for a buffer is a good shaft, and despite the thing being sourced/made in Taiwan they went with a cheapo steel rod that is threaded on the ends instead of something machined and trued.

With the wobbly shaft on the Stewmac, I'd usually use my Caswell even though it hasn't got quite as much clearance and spins faster. I'm buffing set-neck solidbody electrics and there are lots of areas that can't be buffed anyway, and the slightly less clearance on the Caswell just means a little more hand work. Right now I have coarse and medium on the Caswell, where I spend more buffing time and fine and extra fine on the Stewmac. I've gone to only dry sanding nitro so I need to start with coarse.

If I were in your shoes I would contact them before placing the order and ask for one that has been tested by them to make sure the shaft doesn't wobble. If they won't do that or promise to exchange then walk. They offered a full refund incl shipping but not an exchange after confirming with their R&D guys that mine performed within tolerance of the ones they have checked and an exchange likely would not help. Unfortunately it's a kit that must be assembled before you can tell how it runs and I spent a bunch of time making the base and putting it together so a refund, while nice, is tossing that time/$ and starting all over.

That wouldn't have fixed the bent shaft problems on my buffer. The first shaft was so bent I didn't dare load the buffs. The replacement shaft they sent me free of charge was usable, but still bent. It's really all about the shaft on any buffer. All the other bits and pieces (bearings, motors, switches, pulleys, V-belts, etc.) are pretty standard off-the-shelf engineering parts.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Mike, this is the tutorial I did a while ago.
viewtopic.php?f=10117&t=16049

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Dave
Milton, ON

Thanks Rand;

Thanks.

As long as you post pics! Have you made a choice on the buffer yet? I have the Caswell with canton flannel buffs (two on each end). I know others called it a toy, but it works for me just fine.

Richard, I have been using a pair of Caswell machines for over five years now. I buff with four different Menzerna bars and I run 16" wheels custom made from jascar and after more than 500 guitars, they are both still running strong.

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jw ( o)===:::

Wondering what average cost is for a machine shop to prepare a shaft for this purpose.
Seems that one can obtain higher quality shaft material than what the vendors are supplying with their units?

TGP shaft in diameter and length of choice seems to be available.
Stopping point for most seems to be the threads; perhaps that was the purpose of using the go-kart axles.

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Always have plenty of sandpaper; it's rough out there!

Right on. When I'm buffing a steel string, sometimes I wish I had more space between the guitar and motor. Other than that, I can't complain. My lacquer gets glossy.

After reading this thread last night I got to wondering the same thing. I found a 6 foot long 1 1/4" TGP shaft for @60.00 and today I emailed a machine shop about cutting the threads. HE emailed me back and gave me a number to call to talk to him, he wanted to know what size of threads I want? other than right hand on one side and left hand on the other I am not sure what size of threads ?

I was first thinking I would need to turn a shoulder on the shaft for the buffs but after seeing this buffer http://www.amazon.com/Shop-Fox-W1681-Bu ... B005W1C8GG it looks like it would work fine to cut enough threads to just put a nut along with some kind of stiffener plate on each side. How wide are the buffs? how wide would you cut the threads? would 4" or 5" be enough?

My shaft is 1-1/2", with the ends turned down to accomodate 1-1/4", 12 TPI thread. Thread length is 4-1/2".
My reason for going with that size was because I obtained several cases of buffs from a business auction, and they all had 1-1/4" holes.
You can either have your buffing wheels custom-made, or purchase from the common vendors (Stewmac, Grizzly, etc.). Generally speaking, common hole sizes for this type of work can range from 1/2" to 1-1/4".
Try your best to pick a hole size suitable to your needs and stay with it.

When designing shop-built equipment, economy is always at the forefront, but many (including me at first) mistakenly believe that sizing the arbor on the "small side" will allow them to use adaptors if they happen to come across a good deal on buffs with different sizes of center holes. IOW, making the equipment more universal.
Adaptors are available to enable use of larger center holes (in the wheel) with a smaller arbor. Caution should be exercised here, as the purpose of larger arbors is to minimize flex. When shopping around for wheels, you'll notice that it is not common for the larger-diameter wheels (above 12") to be offered with small center holes. They're available, just not as common (for good reason).
Example: I've used the adaptors to run 10" diameter wheels with 7/8" arbor holes on a 5/8" thread, but I definitely would not feel comfortable adapting a 14" wheel with 1" hole on that same 5/8" thread. That particular machine was built years ago with the intention of using it for "small stuff" (knives, tools, etc.). It has a 3/4" shaft with 5/8" threads, and the most common wheel diameter used on it is 6"-8".
Keep in mind the weak link in the system is the point of smallest diameter. There's a reason why we don't usually see 1-1/4" shafts with the ends turned down to accomodate 3/4" threads. Simply put, unless you have an unusual application, you're wasting the capability of the large shaft.
A unique exception would be if you planned to use only small-diameter wheels (with accordingly small center holes) to accomodate built-in speed requirements, yet the project at hand required extremely long shaft clearance, in which case the large-diameter shaft is needed to minimize flex throughout its length.

Regarding the need for a shoulder, it's nice to have one, but I've seen and used machines without them. Whatever method is used to provide a stopping point seems to work OK, even if it means welding a flanged nut to the shaft.
Locking nuts, collars, etc. of various designs are available, and that is what I would recommend. This allows you to keep the buffs located on the outboard side of the threads for those instances when you choose to "go narrow" on the buff width.

Speaking of buff width, the buffs you are apt to use for this application are most commonly available in widths of 1/2" to 1", with the most common scenario being to gang two or more buffing wheels together to obtain desired total width.
The width you need will depend upon project requirements. Going wide gives the ability to finish large areas quicker and more consistently, while going narrow allows confidence when navigating complex shapes and areas. For guitars, "complex" could mean a cutaway, an unusually tight waist, or the neck-to-body junction on a Classical, or any other situation where you emphasize control over speed.
Important to remember is that for a given diameter of wheel, the wider you go, the higher the power requirement (motor). So don't expect to run 16" wheels ganged together for a width of 4" on 110v power.
To answer your question regarding thread length, the 4"-5" you mentioned will probably be plenty for your circumstances. That would be plenty of room to accomodate the nuts, washers, flanges, and reasonable wheel widths. Go as long ("wide") as you want, but see if your machinist charges by the the inch.
Be sure to have it threaded for a commonly available nut. (TPI)

Now for the disclaimer:
I've cobbled together more than a few buffing units, but I am not an engineer, and I know very little about machining. The individual who turned the threads for our shafts was the same machinist who turned the crankshafts and bored/honed the cylinders for our engines. The cost for "side projects" was quite often a decent lunch and/or a 6-pack after work.
In other words, I can't tell you what today's prices would be in order to compare cost effectiveness of building your own versus purchasing a unit from one of the vendors. I suspect that reasonable "resourcefulness" would still allow us to build higher quality, meaning not necessarily more monetary savings overall, but more quality for the money.
The machinist mentioned always did a quality check on the shaft (straightness, roundness, etc.) before cutting the threads, and checked it before it left the shop. That in itself is reason enough for me to consider the "make-your-own" option.

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Always have plenty of sandpaper; it's rough out there!