Presto K-10 - fumblings of a newbie

[CIVIL_PRIMATE]

Yo!
Long time lurker, first time poster. I'll try to keep this concise. I just acquired a Presto K-10 cutter, my first foray into this wonderful world. I've been experimenting nonstop, cutting on different materials and generally messing around. I understand that with these machines, and indeed with the art of cutting itself you need a curious mind and lots of energy. These things I have. Technical know-how, on the other hand, I am desperate for.

Anyway, I feel bad bugging/PMing user:Jesus H. Chrysler, so I thought I'd open this up to the general public. Know that I have made much use of the WIKI, the newbie posts and the search function, but there are things I can't seem to find and hopefully someone could point me in the right direction, offer tips, etc.

To start, my set up is the K-10 with a Yamaha receiver connected to an iPod feeding in. I've managed to get audible music fairly quickly. I'm now trying to figure out the nuances of the machine.

1) How do I stabilize the arm/stylus in order to get a consistently cut groove? I'll put down some plastic and sometimes it will dig in a couple times per revolution, or dip, or skim certain sections. I feel like I'm careful when placing the plastic down, taping it evenly. Is there some other adjustment I'm not factoring in, outside of the vertical positioning of the cutter head?

2) There seems to be a 'cloud' of fuzz coating the music I've cut. ***I understand this machine will produce decidedly lo-fi results*** but I have heard other demonstrations from the K-10 and they sound much cleaner than the sound I'm producing. Are there things that come to mind that I should be considerate of outside of EQ, distortion, and so forth? Could it possibly be that I need to clean or replace something?

I'm not asking anyone to definitely answer these questions per se - I understand there are too many details left out for that. But if anyone has any general tips from experience using this model, things they've found helpful, tricks, tips, etc - that would be marvelous.

I'm just an amateur looking to get deeper into cutting; I'm a hard worker and I'm not asking anyone to handfeed me entire servings of technique. Just a few morsels of wisdom would be gratefully accepted.

TROLLS OF THE LATHE, I APPEAL TO YOU!

Thanks in advance,
Jordan

[piaptk]

What are you cutting on? Picnic plates? Poly? Lacquers?
What kind of needles are you using?

The first step in figuring out if something is wrong with your machine or your setup would be to cut a lacquer with a new, known to be good, needle. Then if you still have the cloud of fuzz, you know it's something with the amplifier or head, not your material...

Sounds like you are cutting picnic plates, but you will always fight them pulling up in certain sections, regardless of how carefully you tape them down. They are just too flexible. They do, however, lie flatter on one side than the other...

[CIVIL_PRIMATE]

Thanks for the reply! Exactly what I was looking for...

Yeah I haven't graduated to poly, lacquers, etc. just yet. I'm cutting on a variety of consumer-grade plastics such as picnic plates/solo plates, garage sale signs and so forth.

I've gotten in touch with West Tech Services about a needle because, like you said, I just don't know what a good needle sounds like so I need to at least do a compare/contrast & go from there. I have no idea what kind of needle is in there right now.

Thanks again and I'll report back with any progress/regress.

[piaptk]

Thats what i figured. I doubt the problem is in your machine, its woth your needle and your medium. Call apollo and prder a good needle and 1 lacquer. If you are lucky they will package the lacquer between two partially used ones that you can also experiment with.

You sound like me when i first started with a suitcase cutter from west tech and a handful of steel styli (totally worthless) and picnic plates or cardboard based lacquers. I wasted months trying to make that combo sound even sorta decent. Once i bought a new sapphire and a new lacquer, i was able to isolate variables and actually started figuring out how to use the thing.

A lacquer and sapphire arent cheap, but they are way worth it to verify that the setup is working and your stylus weight is appropriate.

Also, stylus weight could be a contributing factor to your picnic plates not laying right, the atylus could be dragging it a little.

Another tip: dont try poly with your new stylus. You will ruin it.

[piaptk]

Also, stick to picnic plates, lacquers, and acrylic. Garage sale signs, placemats, xrays, etc are more likely to hurt your styli than they are to give you decent results.

[maniman]

Yes yes , if i understand what you wanna try i guess really the most sharpened cutting needle , less weight for the same deep , if you need more weight maybe your problem is the sharpness ...

[Jesus H Chrysler]

Sorry I didn't get back to you sooner. I don't always sign in when I come here and didn't see the message.
In answer to your question about input volume, I like to keep the volume on the presto between 3.5 and 4 and adjust the source volume to get a good output. I use a powered eq between my source and the presto and set the presto's tone at 0, but if you don't have one, it'll still cut pretty well with the tone knob turned halfway to the right. Don't worry too much if the meter goes out of the green range as long as most of the audio stays near it. I usually run mine where the needle bounces off the peg on the loudest bits.

On cutting depth/weight: I cut best if the needle leans back 10 to 15 degrees. You can adjust that by raising or lowering the head in it's bracket. the weight is controlled by the thumbscrew attached to the spring. keep fiddling with that until you get the best results.

Try the lighter colored opaque picnic plates (white, pink, yellow, orange, etc) they tend to cut with less surface noise than red or black or translucent. I get mine from party city. Also the bottom side always cuts better.

If you haven't already, pull the platter and lubricate the gears. The manual says to use petroleum jelly. That works fine for me.

Hope that helps.

[CIVIL_PRIMATE]

So much great info all around. Thanks so much to all you guys for the tips and tricks - exactly what I was looking for. I like fiddling around with it, it's *obviously* not a chore, but it's great to get some time-saving tips every once in a while.

I've ordered a new needle from Apollo, so that's kind of my new launching-off point. I'm going to take all the other great stuff said in this thread and apply directly.

Thanks once again, I will keep you guys posted with more failures/minor successes.

[Angus McCarthy]

I'm still not clear, are you driving the head directly with the Yamaha or with the on-board amplifier? If it's the latter and things still sound "fuzzy" even after lowering the input level and other fixes, you may need to replace the capacitors which will probably have have dried out. Also, it may be worth having Gib check out the head itself if the quality doesn't improve from the other methods.

[CIVIL_PRIMATE]

I'm not sure if I can concisely answer the question of amp driving - excuse my ignorance here. What I've got going right now looks like this:

iPod->Yamaha Receiver->Presto input

I'm using the receiver as a more defined EQ/pre-amp for the music. With this set up, am I still using the Presto amp to drive the head or does this bypass the on-board? If this isn't already bypassing the amp, how would I do that? I'd prefer to do it all with the Yamaha if I'm not already.

The apollo order comes in tomorrow, so hopefully by playing around with that stuff, I'll know more and get a proper diagnosis going. I'm going to run through the Presto and clean all necessary parts.

[Angus McCarthy]

I see. I'm assuming you are currently using a Line level output from the Yamaha? (Tape Rec outputs?) You can directly run the cutting head from the 8-ohm speaker outs of the receiver (or any 8-ohm amp), but this introduces a much higher risk of burning up the head if you are not very careful. All you have to do is run speaker cable from the Yamaha and splice it into the wires coming from the head. If you are going to try this, definitely put a 1Amp or 2Amp fuse in the circuit, just for safety's sake. I speak from unfortunate experience

All in all, though, you're better off getting the Presto amp in top condition and driving it with that, since it was built and tuned specifically for that use. Plus, it's a tube amp, and sending the last stage through an analogue amp can help round off any harsh edges that may be coming out of the source audio.

[Jesus H Chrysler]

I second what Angus said about the caps. If it's been sitting a while they will probably need going through. If you're handy with a soldering iron it can be done in an afternoon. If you got a a manual with it it should have the schematics and partslist. If you don't have one I'm pretty sure someone scanned and uploaded one in the reference section. I got my caps from justradios.com.

[canadiansynthetics]

Hi,
I have some questions about K10s but first, for CIVIL_PRIMATE these are my tips from experience, if I'm wrong about any of this someone correct me:

If your signal is a simple clean sound, like one micd instrument, or synth stuff, you can really push the level needle all the way to the right with very little distortion and mask surface noise. For complex signals like a metal or garage band it's going to sound a lot more fuzzy.

Using a many-band EQ can go a long way whatever your source. Boosting the highest frequencies in your source a little can mask fuzz or hiss-type noise, and taking down the 1-2k neighbourhood a bit can really fill out the spectrum in some cases.

If you haven't already, use the speaker lid to monitor, it's very loud but it's really useful for setting EQ and levels and finding the distort point. If you don't have the lid, get a pair of headphones with a volume knob on them cause the output is way too powerful for normal headphones as you have probably discovered.

Needle heat seems to improve volume more than sound.

You can get more volume if you slow down your recordings by 73.3% in a digital editing program and cut them like that, this will make your discs play the music back properly at 45rpm.

Bad materials can kill a needle very fast. Acrylic is the only thing that's ever worked for me, you can make cut after cut with it and the needle stays fresh.

I agree with JHC that input at 4 is a good place to be.

I came to this thread cause tonight I'm tearing my hair out with my dear K10. I was cutting acrylic in March and did a great run, tonight I'm back on it with a new stylus and the sound of a silent groove has degraded very significantly. I have questions pertinent to this situation, and some I've always been meaning to ask. I thought it'd be ok to throw them on this tread since there seem to be a lot of knowledgeable people throwing down here, and some of my questions may be future issues for CivilPrimate.

Has anyone ever got a bum stylus from Apollo that they had to send back? Cause I'm starting to think that might be the problem tonight, but I've been through 8 or so with no issues. I've gone from crystal clear sound to something terrible.

Under the microscope my grooves now are a very thin line and it sounds rough. On the good-sounding recs the grooves are wider and have a shiny bright line on one side of the trench, and there's lots of variation across each trench in shininess. Anything I should make of this?

Is it important to connect a ground wire to the post at the back like it says in the manual, and attach it to a radiator or something grounded in the house? It doesn't seem to make any difference, but like I said I'm goin nuts here. My plug is two-prong.

If the caps haven't been changed ever, is it a sure thing that they need to be? Is there any way I can tell if they've already been changed? I have gotten perfect sound, low level, but excellent. But replace them I will if I really should.

Is anyone able to cut at volume levels comparable to commercially pressed wax?

Anyone have preferred DC settings for ruby needle heat? 0.49A and 2.0V or slightly higher is the neighbourhood I play around in cutting acrylic and I always wonder if I'm way off base.

For the real pros: how temperature sensitive are these machines? I'm up north and the temp in my uninsulated attic ranges from probably 46F to way up around 90F, with 100% humidity. Am I torturing my baby?

I always had my tone set to 10, anything less sounds really muffled. JHC do you have the treble on your EQ cranked?

Does anyone who cuts with acrylic do anything to prep the material, temperature or otherwise?

I appreciate any thoughts on any of these questions.

[CIVIL_PRIMATE]

Hello! I'm back!

canadiansynthetic, I really appreciate your post and I don't consider it hijacking the thread at all, it's entirely appropriate. Good tips in there and I would love to hear more.

I acquired a new sapphire needle from Apollo and things have taken a huge turn for the better. I'm not exactly sure what was in there before but the Sapphire is beyond an improvement. I've come pretty close to the sound I'm looking for. I'm gearing up to start my first full run of records, so we'll see what the quality/consistency ratio is. One thing I was wondering - is the monofiliment that's attached to the needle from Apollo necessary to use in the K10 or can I just cut it off? Right now it's still intact because again I have no idea how most of this stuff works.

When you say you use acrylic only, specifically where do you acquire it? I get overwhelmed by options on stuff like that and would appreciate any links or direct outlets where you purchase materials.

Lastly, and I am going to start a new thread on this topic but figured I'd ask here first: is there any way to plane (otherwise, to erase the grooves from) vinyl records? I completely understand the sound quality would not be good but this is a theory question here and I'd like to hear how it'd be done if possible.

Thanks again!

[piaptk]

Hello! I'm back!

canadiansynthetic, I really appreciate your post and I don't consider it hijacking the thread at all, it's entirely appropriate. Good tips in there and I would love to hear more.

I acquired a new sapphire needle from Apollo and things have taken a huge turn for the better. I'm not exactly sure what was in there before but the Sapphire is beyond an improvement. I've come pretty close to the sound I'm looking for. I'm gearing up to start my first full run of records, so we'll see what the quality/consistency ratio is. One thing I was wondering - is the monofiliment that's attached to the needle from Apollo necessary to use in the K10 or can I just cut it off? Right now it's still intact because again I have no idea how most of this stuff works.

When you say you use acrylic only, specifically where do you acquire it? I get overwhelmed by options on stuff like that and would appreciate any links or direct outlets where you purchase materials.

Lastly, and I am going to start a new thread on this topic but figured I'd ask here first: is there any way to plane (otherwise, to erase the grooves from) vinyl records? I completely understand the sound quality would not be good but this is a theory question here and I'd like to hear how it'd be done if possible.

Thanks again!

RE: Heater thread:
You can cut that off if you aren't using a stylus heater. Heating the stylus will increase stylus life and decrease surface noise, but you can't really use it without a vacuum setup, which would probably be fairly difficult to set up on a k10.

RE: Acrylic:
Look in the phone book for Plastics Suppliers in your area. Call them and ask about buying a 4'x8' sheet cut into 6.7" squares. They make a million different colors of acrylic, but start with clear... then buy remnants of the other colors from them before you buy entire sheets. I had really random and mixed results with colored acrylic.

RE: Planing off the grooves of a record:
Will be very difficult and not very useful. You can't cut PVC (the stuff records are made of) with anything but a diamond, and you definitely don't want to waste a diamond on an uneven, wonky planed off record. I've got a handful of blank PVC 7"s I'll sell you if you really want to try cutting PVC.

[CIVIL_PRIMATE]

PIAPTK you sir are a gentleman and a scholar! Thanks for the info!

Two more quick questions when you've got a minute:

1) What is the optimum thickness for the acrylic from 0.060" to 1.500"?

2) Stupid question but I imagine you use a drill press to manufacture the center holes on these?

[tragwag]

the poly we use is 1/16" thick.
which, in decimal is .06

[Jesus H Chrysler]

I get my acrylic from Lowe's in 35 x 30 sheets (around 20 bucks a sheet) and cut it down to 7" squares on a table saw. the stuff they sell is .080" (optix brand)
re: my eq, I have it set up as a sloppy approximation of a reverse RIAA curve, so yeah the highs are boosted up to 10khz but I kill everything above 12khz and below 100hz since the head can't reproduce it anyway

re: the caps, When mine went bad, it was obvious. It was cutting fine, then the volume dropped dramatically and I had to crank it all the way up just to get a really shitty distorted sound. So if yours sound ok, I wouldn't worry about it but they will go bad eventually. The only way to tell if they've been replaced is to pull the amp chassis out and look at them. They're underneath.

Mine had a 3 prong plug put on it at some point, so I don't bother with that, but if you're getting an odd hum or buzz when cutting from a line source like a tape or cd player, you might try running a wire from the post to the chassis of the source

I use a commercial paper drill press (hollow bit) I work in a print shop. You can do it with a regular handheld drill but be careful because it's easy to crack it. The bit size is 9/32

[canadiansynthetics]

Thanks so much for the info JHC.

I called Apollo about the stylus that seemed like it might have arrived damaged, and they immediately sent me a new one and asked me to mail them the old one no charge. It was in my hands within a day and it cut great. My hair is beginning to grow back and everything.