|
|
Post by limousinlady on Sept 25, 2021 15:29:47 GMT 1
Our Parkside compressor has just blown, after about 8 years, and we are going to have to replace it to continue with ongoing projects. Conveniently, Lidl's will have compressors coming up next Monday, but one of the likely future projects is re-rendering a very high side of the house, for which we will want to use a machine. The compressor that Lidl is selling and the one we have, we know will not be powerful enough for this job. Can anyone advise how powerful a compressor we would need? as it would probably make sense just to invest in the larger machine now if the cost isn't too prohibitive.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Sept 25, 2021 16:45:41 GMT 1
Having seen the limitations of my small MacAllister, I'd definitely go for a bigger option next time. Now you've considered it, you'll only be disappointed sooner or later if you don’t.
|
|
|
|
Post by limousinlady on Sept 25, 2021 16:49:38 GMT 1
Having seen the limitations of my small MacAllister, I'd definitely go for a bigger option next time. Now you've considered it, you'll only be disappointed sooner or later if you don’t. But how powerful do we need to go to do the crepi work? |
|
|
|
Post by Polarengineer on Sept 25, 2021 17:08:01 GMT 1
Your crepi blower gadget nozzle thingy should specify the air requirements, if not, look up the model on the net and get as much info from it as you can. Then check the same for air driven tools that you have or may want in the future. This will give you the air flow and pressure you need from your compressor and be sure the tank is over 100 ltr or the compressor will keep starting and stopping or not stop at all and slowly run down the pressure. I would expect you will need 3 phase power as the larger motors have a large starting current. It could be 3 or 4 kW.
|
|
|
|
Post by limousinlady on Sept 25, 2021 18:35:07 GMT 1
Your crepi blower gadget nozzle thingy should specify the air requirements, if not, look up the model on the net and get as much info from it as you can. Then check the same for air driven tools that you have or may want in the future. This will give you the air flow and pressure you need from your compressor and be sure the tank is over 100 ltr or the compressor will keep starting and stopping or not stop at all and slowly run down the pressure. I would expect you will need 3 phase power as the larger motors have a large starting current. It could be 3 or 4 kW. Thanks for the info. We haven't got the crepi gadget yet. As our present compressor has gone kaput we are trying to forward plan by buying a new one capable of doing future projects. But will definitely follow your thinking and look up what the tools require with regards to pressure. Good advice. |
|
exile
Member
Massif Central
Posts: 2,031
|
Post by exile on Sept 25, 2021 19:57:02 GMT 1
If you have ongoing need for a compressor but the crepi job is just a one off, have you considered renting a compressor for the crepi job and buying a smaller one for the day to day usages
|
|
|
|
Post by pcpa on Sept 25, 2021 20:26:01 GMT 1
First of all dismiss any direct drive compressor (one without belts and pulleys) and especially any claims made of hp and flow rate, they are all fantasy.
Do not buy any compressor with a brush motor, the rated power is based on the stall current when the windings are burning out, fantasy again like the flow rates they quote.
An induction motor belt drive compressor will give the true shaft horsepower of the motor and the flow rates are more likely to be closer to the truth, FAD (free air delivery) means nothing as your Crepinette will want to operate at 6 bar +.
I have a 40 year old 3hp Italian belt drive compressor and have done hundreds of hours of crepi work using a Crepinette, it has a 50l tank and with the reservoir pressurised to 10 bar (most of the new ones will be lower) and the regulator set to 6 bar I can just about empty the hopper of the crepinette by the time it has dropped to 4.5 bar and is spitting, the tank will be refilled in the time that it takes me to refill the hopper.
Budget for buying a replacement motor, the one it comes with wont last long under proper use, if it has a thermal cut out switch then you will have to remove the cover to let it breath or it will be cutting out all the time (I had to do that with mine today) but this will also reduce the life of the motor.
If you manage to find an Italian made motor as the replacement & not just one bought from China by an Italian company then you will get years of service from it, otherwise you will be regularly replacing the Chinese motors & it would pay to keep 2 as spares.
My compressor was used by me very regularly for car spraying & then for crepi and render, back in 1990 a friend used it to Tyrolea render his huge property, the original motor lasted 30 years, the Ebay replacement only 6 months, then I was lucky to find a genuine Italian one with thermal overload protection and touch wood 10 years later its still in fine shape, I spent all afternoon using it changing trailer tyres.
Iwonder whether anyone in Europe is still actually making induction motors, even 20 years ago it was uneconomic to have a rewind on anything less than a 15hp 3 phase motor.
|
|
|
|
Post by limousinlady on Sept 25, 2021 20:31:12 GMT 1
First of all dismiss any direct drive compressor (one without belts and pulleys) and especially any claims made of hp and flow rate, they are all fantasy.
Do not buy any compressor with a brush motor, the rated power is based on the stall current when the windings are burning out, fantasy again like the flow rates they quote.
An induction motor belt drive compressor will give the true shaft horsepower of the motor and the flow rates are more likely to be closer to the truth, FAD (free air delivery) means nothing as your Crepinette will want to operate at 6 bar +.
I have a 40 year old 3hp Italian belt drive compressor and have done hundreds of hours of crepi work using a Crepinette, it has a 50l tank and with the reservoir pressurised to 10 bar (most of the new ones will be lower) and the regulator set to 6 bar I can just about empty the hopper of the crepinette by the time it has dropped to 4.5 bar and is spitting, the tank will be refilled in the time that it takes me to refill the hopper.
Budget for buying a replacement motor, the one it comes with wont last long under proper use, if it has a thermal cut out switch then you will have to remove the cover to let it breath or it will be cutting out all the time (I had to do that with mine today) but this will also reduce the life of the motor.
If you manage to find an Italian made motor as the replacement & not just one bought from China by an Italian company then you will get years of service from it, otherwise you will be regularly replacing the Chinese motors & it would pay to keep 2 as spares.
My compressor was used by me very regularly for car spraying & then for crepi and render, back in 1990 a friend used it to Tyrolea render his huge property, the original motor lasted 30 years, the Ebay replacement only 6 months, then I was lucky to find a genuine Italian one with thermal overload protection and touch wood 10 years later its still in fine shape, I spent all afternoon using it changing trailer tyres.
Iwonder whether anyone in Europe is still actually making induction motors, even 20 years ago it was uneconomic to have a rewind on anything less than a 15hp 3 phase motor.
Thanks for the detailed reply. I have passed to the OH to understand and mull over. |
|
|
|
Post by limousinlady on Sept 25, 2021 20:36:10 GMT 1
If you have ongoing need for a compressor but the crepi job is just a one off, have you considered renting a compressor for the crepi job and buying a smaller one for the day to day usages It is surprising how much we do use the compressor as OH tells me. At the moment it is getting a lot of use with the air chisel for prepping walls for re-pointing. It could be more economical to rent one fit for purpose for the crepi work. I suppose it will depend on the price for hiring compared to buying. Another option to consider. Thanks. |
|
|
|
Post by pcpa on Sept 26, 2021 1:31:13 GMT 1
A pal had a 8hp petrol site compressor, it was like a big wheelbarrow, no reservoir as such, it used the tubular frame which was a minimum volume to damp out the pump pulsations, it would idle and pour on the coals when air was drawn.
It was perfect for my crepinette and the pressure never dropped, I used it mainly for my bigger render gun called a sablon which is like a bucket hopper on the end of a pole which you use to shovel up the render from a wheelbarrow, it drew too much air for my 3hp compressor, if you are going to hire something then that would be the size to go for, a big trailer mounted TP compressor is overkill.
Be aware that these bigger compressors use raccord à pompiers and you should really use a large bore hose to get the most out of them but then the weight becomes a problem, the crepinette is heavy enough when you are using it all day.
|
|
|
|
Post by hal on Sept 26, 2021 9:10:24 GMT 1
Your original comment that you had a very high side of a house to render, coupled to pcpa's comment that these crepi devices are quite heavy, especially when used high up are the two that I note over what power you need...
I pick up and extend exile's suggestion - buy a compressor for your everyday needs but bring in a professional crepi enterprise to do the high up render. For me, a no brainer...
|
|
|
|
Post by Polarengineer on Sept 26, 2021 11:02:51 GMT 1
You take all the fun out of it Hal.
|
|
|
|
Post by limousinlady on Sept 26, 2021 11:06:38 GMT 1
Your original comment that you had a very high side of a house to render, coupled to pcpa's comment that these crepi devices are quite heavy, especially when used high up are the two that I note over what power you need... I pick up and extend exile's suggestion - buy a compressor for your everyday needs but bring in a professional crepi enterprise to do the high up render. For me, a no brainer... We have scaffold and we got a quote a couple of years back and they wanted Eu.8k. Too much for us to spend on one wall. |
|
|
|
Post by pcpa on Sept 26, 2021 11:49:42 GMT 1
When you speak of crépi do you mean the grained textured paint finish or a monocouche render that would go on 2cm thick & have a trowelled or grated/scratched finish?
|
|
|
|
Post by limousinlady on Sept 27, 2021 17:54:19 GMT 1
When you speak of crépi do you mean the grained textured paint finish or a monocouche render that would go on 2cm thick & have a trowelled or grated/scratched finish? I've not been very knowledgeable around the terminology, but we would definitely need to remove most of the existing render if not all. So the second; monocouche render. For the last couple of years, we have been growing virginia creeper (non invasive) to hide it but should really address the problem. |
|
