Dedicated power supply for Tire Razor

[Giddyup]

Hi Folks,

I’ve been using my track power (Pyramid PS26) to power my Tire Razor and now I want to buy something dedicated for the truer that’s is a smaller form factor that is portable, and not going to run me $100 while being reliable/safe. For context, I run on urethanes, so that’s what I’ll be truing.

I’m starting to research options, but does anyone know what sort of amperage I should be considering?

I’ve seen some generic lab power supply which are 5A and have variable voltage on Amazon, looks like they’d be suitable. But it seems like they may all be Chinese made since they all look th same bu travel different brand names. So not sure about their quality/reliability.

I also found a MW122A model searching here on the forum that is 2A that people have gone with. This MW122A having a 3V, 5v and I think 12v option which also fine for my purposes as I’d like to be able to run in motors at 3V. But after a bit of reading, seems like they quality may be suspect?

Aside from determining how much amps i may need, I’m just curious what people are using for their Tire Razor other than their track power that would meet my criteria above.

Oh, and as a last resort, I’m also thinking about replicating this since it looks fairly straight forward:
https://www.instructables.com/id/Conver ... r-DC-Powe/

Thanks,
Tom

[SpeedyNH]

things may have changed, but in the past I have found the following issues with using desktop computer power supplies as stand-alone units:
internally, the main section is the 5V output, and the others are driven by and slaved to that. it's a pulse-width modulated supply, and without significantly loading down the 5V output, the controlling pulse width is not wide enough to provide much output from the slaves. this is mentioned in the article above, but the author talks about loading down the 12V section. maybe things have changed, but I think that this is incorrect. (at least it sure used to be!) either way, what one ends up with is a selectable or single fixed output unit rather than variable. I like to tweak mine around a lot, so without an external adjustable series regulator, it doesn't provide the adjustability that I would want.
these things are kind of a pita for me because aside from the size (and the audible fan), when you're trying to just get something like a decent adjustable 12V output, you've got that big wasteful half-Ohm (or less) 5V power resistor sitting there cooking, and then another little metal box (or bracket) tacked on with the pot and the power circuitry for the add-on external regulator.
sorry about that. just my take.

anyway, on my tire truers (some are kind of old), I use a cheapo Chinese-made Amazonian adjustable curent-and-Voltage supply of 15V (more than enough) and 5A (just barely enough) supply. my current one (pun intended) is labeled HY1505D. it's about 3-1/2" wide by 9"dp by 6" high and the adjustable current limit is very useful. the only thing that it Doesn't have is a backlight for the two LCD displays. but as they say, one gets what one pays for.
Speedy

[HomeRacingWorld]

[Broman62]

YEPPER...I agree...I have one similar to Harry’s and I run my Razor and whatever I need and that price is great for what you need!!

[Slot GT]

I've been using a Professor Motor PMTR1400 15 Amp 6-20V Power Supply for my Tire Razor for over 5 years now and it's never let me down.

[Giddyup]

Thanks for the advice so far. :text-thankyouyellow:

For the one Harry pointed to, thanks Harry :D .... and not to discount Harry’s advice by any means, but I am curious to hear from others who have used a similar one - has anyone experienced either (a) quality issues or (b) it has cut out when truing due to insufficient amperage? Just casting a wider net to hear what others have experienced with his recommended unit...and to ensure 5A will be enough before I dole out any moolah, thanks!

BTW Slot GT, that looks like a nice option, but also looks like it could be pricey? As I mentioned in my original post, I’m trying to keep the cost well below a 100$ (and CAD $ at that) as I just want a dedicated and portable power supply for my truer.

[dw5555]

[PetesLightKits]

Sorry, I boo-booed.

Peter

[Giddyup]

Hi Dave,

As I mentioned above,I’m just truing urethanes. Part of my original question was how around how much amperage would Tire Razor draw/need. I’ve read through other threads on HRW it could be over 2A. And I think that was from Jon himself.

So, all I’m after is a minimum amperage to help me narrow down choices. Harry pointed out one model above that was 2A. Hence, I asked the question if anyone who’s used that model has ever experienced it cut out during truing (and if anyone has experienced any quality issues with it).

[Slot GT]

[SpeedyNH]

hi DW,
thanks for the reply.
I know- the toughest ones I have are silicone tires on a hudy with an old RC motor, left over from my Eurosport days. sometimes I see 3.5A or so with the old coarse sanding drum- it's gets pretty hungry. it might be like a 6 or 8 turn (touring?) motor, but the label is long gone. IIRC, that's at about 3-4V, with those pulleys.
with that unit, since my old adjustable 5V 2A jobbie folded back as soon as I touched 'em, I went up to five Amps and all was good. a couple friends have had the same problem so I pointed them to the bigger supplies. urethanes (and rubber tires of course) are much easier.

the tire razor looks like it only wants a couple Amps or so under full load, at what looks like a somewhat higher Voltage. Jon surely includes a more appropriate motor, but I haven't asked him about it.

call me a dinosaur if you wish- I have four different truers dating from the early 1990's to the present. therefore, not knowing what people might be using, I tried to cover all the bases. having lots of current in hand (without driving the price up) won't hurt anything if you are observant of possible meltdowns. (witness Harry's 5A supply and GT's 15-er.)

hey-at least I didn't say TEN Amps! LOL
and btw- don't scatter that motor with those 30V supplies!
v/r
speed

[waaytoomuchintothis]

[SpeedyNH]

an old Les Wright! nice. originally intended for breaking in cobalt motors, i'd bet. I used to build those too.
(does the fan change speed with the output setting?)

[Z-carfan]

I have two of the power supplies that Harry suggested, one runs anything I put in my Carrera track and the other runs my tire truer and sometimes my four lane HO door track. Both have provided trouble free serivce for over a year now. Zero complaints.

[Cgyracer]

Hey Tom......I use a 3amp power supply with my Hudy and Razor. No lack of power with truing rubber or urethane. If I ever have lack of power I accidently turned the adjustment knob too much! Nice and slow cut will get you that trophy Tom!

This is my supply I bought locally.