Bosch GEX 270AE random orbit buffer

[Vincent]

I cant get a PC 7424 in my country so, I found other brand which is BOSCH, the speed range is between 7500rpm(lowest) - 12,000rpm(top speed). Does it suitable to use ? PC slowest speed is 1000rpm right ? Please advise. Thanks

[ZoranC]

Re: Bosch GEX 270AE random orbit buffer

Hi Vincent,

My (far from very educated) guess would be that unit you are looking at would be too strong even at it's lowest setting. Assuming you are talking about random orbital (in which case specs are in OPM - orbits per minute, instead of RPM - rotations per minute) 7500 would be most likely more aggressive than G100 at it's highest setting (6000 OPM). I say most likely because comparing OPM to OPM is not apples to apples, from what I know other factors come into play, like "throw" of the orbit etc. You would be much better off with something that can cover range of approximately 4000 to say 6000 (7000 OPMs at most). From what I know it is highly unlikely you would need something weaker or stronger than that (G100 starts at 2500 but I don't know of uses that say to use speed setting lower than 3, if not 4, out of 6).

[Bence]

Re: Bosch GEX 270AE random orbit buffer

It is definitely not too powerful. The 270 series (PEX/GEX) are great little tools, which can work beautifully. The higher speeds are not problem, because they have smaller pad throw than the PC. They have 4 mm oscillation, which is pretty sufficient for defect removal. But don't expect miracles on hard paints; they have their limits too. However, most paints are correctable with them, you just need a bit more time. One great asset that because of the smaller pad throw, they finish down even the coarser polishes to a very fine level.

[fishbonezken]

Re: Bosch GEX 270AE random orbit buffer

Vincent,
do NOT use speed 5 on the Bosch GEX-270AE.
When I first starting using the machine, I assumed that the speed was the same with the Porter Cable 7424.
I follow the recommended speed for polishing and waxing for the PC7424 divided by 2.

Polishing = 2.5
Waxing = 1.5

I've used speed 2.5 for the Bosch GEX-270AE to break down M80, and it did a good job.

If you used speed 2.5 or maybe higher than 3.
your pad may tear around the edges of the velcro and become like this.

mine tore up when I used it for the first time.

[Vincent]

Re: Bosch GEX 270AE random orbit buffer

Vincent,
do NOT use speed 5 on the Bosch GEX-270AE.
When I first starting using the machine, I assumed that the speed was the same with the Porter Cable 7424.
I follow the recommended speed for polishing and waxing for the PC7424 divided by 2.

Polishing = 2.5
Waxing = 1.5

I've used speed 2.5 for the Bosch GEX-270AE to break down M80, and it did a good job.

If you used speed 2.5 or maybe higher than 3.
your pad may tear around the edges of the velcro and become like this.

mine tore up when I used it for the first time.

Thanks for your responsed, can it finish what you expected ? BTW what pad are you using, Meguairs or other brand ? worth buying or not ? what is the advantages and disadvantages ? sorry for many questions..

[bernard78]

Re: Bosch GEX 270AE random orbit buffer

Hi fishbonezken. Can glue it back ah? Ya I also wanna know some info on the Megs pad, as I'm buying them tis mth end. Thks in advance. Good day.

[Bence]

Re: Bosch GEX 270AE random orbit buffer

Yes, some have succeeded glueing the velcro back using Gorilla Glue, etc.

I forgot that I use this machine to polish CDs and DVDs for a DVD rental company.

[fishbonezken]

Re: Bosch GEX 270AE random orbit buffer

Hi Vincent and bernard78,

I'm glad that you asked if it can be glued back, because that was what I did( you can choose not to read the tutorial), and regretted. Here is what I did trying to glue it back together.
I took a two part epoxy (This one is by the brand, Selley's)


They are both transparent liquid. Mix equal parts and then it will turn white.


Using the end of a cotton bud with the cotton part pulled off, fill in the gap of the torn area with the epoxy.

Here is what it looks like after going around the whole velcro.


let it dry under the sun. (no need sotong/squid) :P

When it is dry, I let it cure for one day, as stated on the instructions of the epoxy. Since then I've used it with ColorX(speed 5) and only recently I used it at the proper speed after being told by Zey(detailing guru) about the OPM difference between Bosch GEX-270AE and the PC7424.

The epoxy I can say held up pretty well, if you put it in pretty thick and let it fully cure before using it. This is what it looks like now.


The black line was me using speed 5 and using too MUCH pressure. The violent oscillation at speed 5 on the Bosch 'burned' through the velcro.

This part is when I applied the epoxy too thinly, and it cracked.




My w-9006 finishing pad also had the same problem, I've posted my problem here before, and Mike Phillips told me that I was using too much pressure.
So I lightened up and used a lower speed, the tearing drastically diminished. (Thanks Mike)

Bottom line is, if you do tear your pad around the edges of the velcro, do NOT glue it back, because if your technique is correct it shouldn't tear.If it tears, just leave it, and correct your technique.
After epoxy-ing my 8006 pad, washing it can sometimes hurt and not comfortable at all, you cannot bend or flex the pad because of the hard epoxy and the uneven rough edges of the dried up epoxy can poke your hands.

I have not tried other pads, I don't even know if there are any alternatives in Malaysia, I've heard some people mentioning 3M, but I don't know where to get them. Meguiar's pads does the job, and that's enough for me.

Well I'm no sifu, but this is what I can tell you:

Learn to apply enough pressure, but not too much.
And do not go past the speed of 2.5.

"Prevention is better than cure", preventing the pad from tearing is MUCH better than having to epoxy it later and suffer through the washings. @_@

I can't say if there are any disadvantages or advantages with the pads because I ahve not tried other pads. But I have no complaints about them. The tearing was my fault, and not the pads.

hmm, since I'm here, might as well talking about washing them. Meguiar's do not recommend washing their pads, so this is solely my opinion only.
Don't wash them in the washing machine, others have complained that the velcro comes off of the pad.
Sometimes you will tempted to throw them in to the washing machine along with your other microfibers after a long and tiresome detail, instead,
let them soak in a bucket of water and dishwashing soap.


You can wash them the next day, the soaking helps.


Hope I was able to help, nice meeting you Bernard78 and Vincent.

[Vincent]

Re: Bosch GEX 270AE random orbit buffer

Fishbone, thank you so much for yr valueable info. I also recomandded buy Zey to get the Bosch 270 but i have yet to get it. You mention about the differences between OPM & RPM, can you tell it more in details please ? How many steps the speed control for this unit ? Starts from 1, 1.5, 2 ,2.5 etc ?

[Bence]

Re: Bosch GEX 270AE random orbit buffer

Bosch specifies OPM and stroke rate. The actual OPMs are 12.000 max, and that means 24.000 stroke rate in Bosch's lingo. Orbit = forth and back; hence the 2 times count.

I'm using this machine since 2004 - always on speed 6 for polishing*. No speed-related problems whatsoever. I use speed 4 when polishing DVDs, and speed 4-6 when working on paint finishes. Some compounds like the lower speed setting initially because it gives the abrasive agglomerates (grit) more initial bite. As the diminishing abrasives break down, the higher speed is able to finish down the primary crystals (broken down, ultra fine abrasives) to a very fine level. I can go directly from heavy compounds to LSPs.

The speed wheel has a smooth, continuous control, and the machine has great ergonomics. The vibration levels are generally low, even with a soaked, heavy pad.


*Not the recommended speed range by Megs

[Vincent]

Re: Bosch GEX 270AE random orbit buffer

wow ! sounds like that's a good machine to consider..Thanks a lots for your sharing..

[Bence]

Re: Bosch GEX 270AE random orbit buffer

Check your PMs.

[bernard78]

Re: Bosch GEX 270AE random orbit buffer

Thks a lot. I've check Bosch Website. Their RPM is way too high lio lor...7500 to 12000 max. If I'm not mistaken the PC/G-100 setting at 3 is bout 3900 rpm and setting 5 is bout 6000 rpm max only. Guess maybe its coz the Megs pad are design & tested for G-100/PC & thus not so compatible with other brand of Orbital Sander machine....? Or maybe it can be the glue that doesn't suit the heat here...? Just saying only.

I have experince products that glue can't stick together coz of humidity and heat issues. Eg some building material products. At the end the manufacturer need to import a special glue from germany that are very expensive to solve the product problems.. Hehe. Just an example...?

I saw a Kinzo Orbital sander at Makro selling at RM69 only. RPM 6000 - 11000 RPM. I am looking for a spec like maybe 700 - 3000 RPM. I just want to apply waxes only. I don't plan to use it for removing major defects. I think u don't use so much or else u'll cut too much of ur paint and u'll need to repaint ur car later...????

[Bence]

Re: Bosch GEX 270AE random orbit buffer

You are confusing RPMs with OPMs.

If you use a rotary polisher, then you have to be in the approx. 600-3000 rotations/revolutions per minute (RPM) bracket.
But when you'll be using a DA, which does its work by jiggling, not rotating, te speed range will be perfectly fine between 5000-25.000 ORBITS per minute (OPM). DA machines typically don't have forced rotation, that's why you can stop the spinning pad easily (it will still jiggle though). Of course, there are dual mode machines which are able to add a forced rotation mode to their dual-action, eccentric mode, but this rotary mode is always slower than a dedicated rotary (500-700 RPMs max.).

The actual performance of a given machine depends on its speed AND its pad throw. A machine with a bigger pad throw (say 8.8 mm) can work at 7000 OPMs easily, but if your machine has a smaller, 3-5 mm pad throw, well you have to compensate it with a higher speed. Don't worry, a DA is a gentle, but serious tool, which will help your work immensely.

[bernard78]

Re: Bosch GEX 270AE random orbit buffer

Hi Bence, Thank you for explaining it to me. I was so afraid of the high speed thats why I reluctant to get a random orbital. I actually wanted to get the rotary coz I saw one with 300 - 1200 rpm. I thought well it's slower and could be safer for my clear coat. Hehehe. Now only I realize there's difference btw OPM & RPM.

Luckily I come across u guys. Thks. I'll try to search for more info to understand this. Thanks for pointing out the right path for me. I research more on OPM vs RPM to understand more. Thks again.