Vinyl Record Sweep Arm Won't Fit Your Home Audio Turntable? Make a Stand!
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Vinyl Record Sweep Arm Won't Fit Your Home Audio Turntable? Make a Stand!
The renewed popularity of vinyl means that many listeners once again have (or of course already had) vinyl record libraries at home that need looking after. At the same time, portable and space-saving small-footprint turntables have become increasingly popular.
As ever, vinyl needs to be kept free of dust. I've long been a fan of the sweep arm, a tonearm-like device that has a brush at the end, plus a soft dust-collecting pad on older designs. You normally attach it to the upper surface of your turntable, where it 'plays' across the disc just as the actual tonearm does, sweeping the record clean immediately ahead of the stylus.
However, a sweep arm needs to be correctly installed. This can be problematic with smaller turntables that have nowhere to put one and also with some full-sized models that have numerous controls or other obstructions. Additionally, anyone owning a very high-quality turntable may prefer to avoid sticking a dangly gadget onto it with a self-adhesive pad.
As I own a turntable with exactly this issue, I decided to create an outboard stand purely to hold a sweep arm, borrowing the general aesthetic from high-end turntables that have an outboard (often secondary) tonearm. At least one boutique manufacturer has produced a similar item, but the example I've seen has a very high build quality, includes its own arm and while excellent could easily cost more than an actual turntable. This DIY version is inexpensive and lets you use any sweep arm including one of my preferred legacy models, an example of which is shown in use here.
Supplies
You will of course need a sweep arm if you don't already have one. Various models are available. For this project it's easier to use one with adjustable height (most have this feature). The example I'm using here is a classic Bib Groov-Kleen that probably dates from the late 1970s (these frequently come up on eBay, often as unused 'new old stock') but I've also shown a contemporary model for reference.
Creating the outboard support is easy enough in principle. All you're doing is making a platform for the arm to sit on, so you could in reality use anything from a book to a can of tuna (I recommend creating some sort of dummy version first anyway, to ensure that the concept works on your turntable) since the only requirements are that the platform is stable, of the correct height and has enough mass to reduce the chance of it being accidentally nudged out of position. However, if you plan to keep your platform in place you may prefer to create something that's reasonably elegant. A nice piece of timber? Something painted or covered to match your turntable or decor? The options are endless.
This being the case, please take this example as a case study. I decided to go for a robust, hi-tech look, so I used a steel doorstop (available from many hardware suppliers) as the platform. These come in various shapes and sizes, so I simply chose one that (a) had the necessary flat upper surface (many are curved) and (b) happened to measure just a fraction below the required height; the arm can be adjusted to compensate for this small discrepancy, as explained in the first step. You'll need to take these factors into account if you also choose this option. A platform that's slightly too high won't work as it offers no scope for useful adjustment.
For this take on the project I also used a small quantity of scrap hardware, some general-purpose adhesive, some epoxy putty and a small piece of self-adhesive baize. With the probable exception of the last item these wouldn't necessarily be required for other versions.
Measuring
The main measurement you'll need is the height from the surface on which the turntable is placed to the top surface of the plinth, as indicated by the red line above. This should ideally be the height of your platform. Note that this measurement needs to include the height of the turntable's feet plus that of any isolation platform or similar that you may be using (unless you plan to park this device on it as well) but should exclude the height/thickness of the turntable platter, which can be matched using the sweep arm's height adjuster. The adjuster will probably have enough range to also allow for a platform that falls very fractionally short of the ideal height. This is the case here, but check first if necessary. When properly set up the arm should supposedly lie horizontally parallel to the record, but in reality a very slight tilt in the direction of the brush can help to keep it in contact with uneven or warped discs, which can be contrived if the arm has an adjustable counterweight.
Construction
Much of this step applies to my chosen repurposed doorstop, so if you happen not to be using one of these, you can skip to instruction (ii) below.
(i) The underside of the doorstop reveals a round, screw-fixed mounting bracket that can simply be tightened firmly into place as it won't be in use. This leaves a small void at the base of the unit (the rest is solid). While the doorstop is quite heavy anyway it's better to have mass rather than empty space in this location for reasons of stability, so this cavity can be filled with anything suitable; lead shot would be ideal, but any odd bits of metal scrap or hardware - in this case some spare nuts - would also work. This ballast can be held in place with some all-purpose adhesive, which isn't something you'd want to use for stress-bearing joints involving metal but it's fine here. Leave a gap of about 1mm between the ballast and the edge of the inverted doorstop, as once the adhesive has dried a smoothed-off layer of epoxy putty can be applied to give a neat finish.
(ii) When the putty has set it can be covered with self-adhesive baize or by using the same adhesive to attach a piece of felt, fabric, soft leather or any other material that would protect the surface it's placed on. If you've opted to make your platform from anything else this is still a good idea. On a larger platform some rubber feet would also work, but make sure you include their depth in your initial measurements.
To complete the assembly, attach the sweep arm to the top of the platform using its self-adhesive pad. You can replace the pad with double-sided tape if the arm's been previously used.
Installation and Use
The introductory photo shows this item being used in a typical situation: a portable player with a small platter, designed to allow a 12" record to overlap the unit's case, thus leaving nowhere to attach the arm directly. Such models usually allow the arm/platform assembly to be placed in a variety of locations, so experiment and just go with whatever works best for you. You'll find that the doorstop's rubber bumper works as a useful finger grip when moving the platform around. On a small-footprint turntable with a full-sized platter the best location tends to be immediately to the left of the plinth, as the platter is usually sited as close to that edge of the plinth as possible.
The idea is that when installed correctly the brush at the end of the arm should trace an arc that would end with it colliding with the spindle if it could (it actually stalls at the runout groove). While this is logical and no doubt desirable, I've never found it to be essential and have obtained good results as long as the arc ends somewhere on the label area.
And that's it!
In Conclusion (and Another Option)
As noted above, many other materials could be used to make this item. However, there's one possible functional, rather than aesthetic, variant that I've not built as I wouldn't find it useful, but others might. It entails adding a horizontal extension to the platform to extend the reach of the arm (think diving board). This might be handy if the ideal location of the arm base isn't where the platform is placed, or if you could in fact attach an arm to your turntable in the conventional way but would rather not. So, taking my own advice about dummy versions I've assembled a working model from an offcut of thin plywood and a small jar of sauce! I've used the slightly more up-market version of the Groov-Kleen for the model purely because I had an example to hand, but as before any sweep arm would work.
The principle should be clear from the above photo. The only variables to be aware of are the thickness and rigidity of the extension (which shouldn't flex) and the weight of the platform itself (which needs to be heavy enough to compensate for the imbalance). With these factors in mind, many materials could be used apart from plywood, such as scrap plastic or aluminium, with the extension being attached to the platform with a countersunk screw or a suitable adhesive. As this version would raise the arm pivot fractionally above the height of the plinth a slightly thicker platter mat could be used to compensate. Maybe try this version if you think it would better suit your needs?
In conclusion, then, I've been very pleased with the functionality of this item and use it regularly, so I hope you find it useful too. If you make one from a different material, please show it in the comments!