Thursday, 31 March 2011

Andtec Builders Review

Recently, we have had our house extended. Since there are lots of people complaining about builders on the internet, I thought I would redress the balance by posting a review of a positive experience we've had with Andtec Builders.
After
After
Before
Before

Andy (Owner of Andtec Builders) was recommended to us by a family friend. We had some plans drawn up by an architect, and we got three builders including Andtec to quote.

Andtec quoted the lowest price: but they had several jobs on, and we'd have to wait several months until they were free. One builder was slightly more expensive (within a few percent) but available now: and one quote was significantly over (40% higher).

We decided to wait for Andy based on the recommendations.

A few weeks before, we met with Andy and talked through the project. Andy had experience with the local area and identified a problem with the foundations specified : our house was built on 'made up' ground and they'd have to dig down a long way to lay the foundations on the 'real' ground level (as specified in the building regs). The original architect was unable to make the changes to the plans but Andy confirmed the problem and found an architect that was able to design a floating raft foundation - a reinforced concrete slab that would do the job.

The original estimate for the work was about 3.5 months : Starting mid november, should have the external walls complete by Xmas, roof on by end Jan, internals done by end Feb.
IMG_0038
The existing garage disappeared very quickly and work on the foundations went well - it was a bit muddy during the excavations but was a lot better once the concrete slab had been poured. Although the work was in front of the door, Andy made sure we had safe access to the house and worked around our many comings and goings :-).

Work on the external walls was delayed a little by extreme weather - during December, we had a very cold snap (-15C at times) and they went to some lengths to keep working - gas heaters, insulation shelters and tarpaulins to try and warm the bricks so that the mortar could set properly without freezing. I know it was cold - we handed out hot tea, and when we collected the mugs a couple of hours later, one was half-full of solid ice! They valiantly worked through the freezing weather - Andy, Jez (the brickie) and George (labourer) only stopped working the week before christmas, where the snow was a few inches deep and couldn't be melted by the salt. In total, several days were lost due to the weather.

January went well - the floors and roofing went on and a few days into February the roofing was done and the scaffolding was coming down. Once the structure was secure, the work knocking through into the main house began.

We had three walls removed, with steel beams inserted, and an extra door through into the hall. This is the most intrusive part of the build : for the first couple of months, most of the work was outside, and didn't really impact on our daily life. My wife is not well, and is at home all the time. Andy went to some effort to try and organise and schedule jobs to minimise the impact on the household, including leaving the kitchen working as long as possible. Luckily, the new kitchen was in part of the new extension, so Andy was able to put in the new kitchen before ripping out the old one, making the transition much easier than it otherwise might be.
This part of the build also went well - although it's inevitably a bit dusty :-).
Finishing
Plastering and finishing was good - we asked Andy to do several extra jobs, which he quoted for and added to the scheduled monthly bills. We asked him to plaster the old kitchen ceiling and replace several internal doors, and to lay a wooden floor throughout the downstairs.

All in all, we were very pleased with Andtec builders and their work. Andy and all the staff were polite and professional at all times, and Andy was always happy to discuss and answer questions about any part of the work.

The estimates and scheduling of the job was excellent : Despite the slippage due to the weather, the work was completed according to the early schedule. The additions to the work (installing a new kitchen, flooring, and extra internal work) all went according to estimates.

Professionalism was excellent : They turned up at 8am every day and worked until 4pm. When they were unable to work (due to the snow) we were informed by phone. Because there was a lot of work, if a particular job could not be done (for example due to tiles not arriving) they continued with other work and rescheduled around problems. Someone else commented that they were very tidy - although it was a building site (literally) it was organised well.
All building regulations, inspections, and certificates (gas, electric work, etc) were all present and correct. Estimates, contracts, changes to the contracts and scheduled bills were printed and very clear and supplied on time, so we always knew what was asked for and how much it would cost.

Andy was polite and helpful at all times. Several times specific decisions had to be made (Front door style, positions of sockets, tiles) and Andy gave us options and time to allow considered decisions before ordering or installing.
Badger (badge)
Along with the building crew, Andy often brought 'Badge' with him. Badger is a lovely border collie, well trained, smart and very friendly. Badge was quite at ease with all the heavy machinery, and would only come in when invited, and didn't jump up or bother anyone - very well behaved. He even made friends with one of our cats (the other two kept well away!).

I would happily recommend AndTec builders to anyone in or around Bath, Frome and Trowbridge.
IMG_0164
Thanks, Andy.

Lots of photos of the build in-progress on my flickr feed.

Tuesday, 13 July 2010

Sentries report bearings to the south west. Thousands of them.

Well, 53 to be exact.

I've been looking around to collect Mendel parts for a little while, intending to reproduce from my BfB Darwin. I've picked up four nema17 steppers, built myself some stepper drivers and electronics, and I'm now looking for the mechanical parts. On the parts lists are a significant number of bearings, which can be quite pricey.
Luckily, I found RepRapKit.com, based in the UK, and ordered myself a complete set of bearings for less than 20 quid - much cheaper than everywhere else I've looked so far. Excellent service - I had a couple of emails with him and he seems like a really nice friendly chap. Parts were ordered and dispatched quickly, and delivered next day. I got 51 smaller bearings and two M8/skate bearings (including enough to make a geared/stepper extruder), they all look good and turn well. The store is selling ABS and bearings so far, and is looking to expand into extruders and other RepRap bits.

I also got round to blowing the dust off my BfB Darwin. It needs several bolts tightening and some general maintenance, and I disassembled the three stepper motors, covered them in plastic bags and tape, and ground out some proper flattened shafts using my dremmel. Note : metal filings from filing or grinding are not good inside a precision engineered bearing, and since they're highly magnetic, it does tend to attract the dust.

Make sure the bearings and motors are nicely covered (with blutack/tape/plastic bags) otherwise the dirty bearings will seize or grind away very quickly.

I'd had a go at filing the shafts back during the initial assembly, but didn't have the right tools - I did have a few problems with the axes slipping at times. Once it's all back together, it should be fine this time.

Friday, 25 June 2010

Heater board complete

I've completed and soldered my heater board.

There are 8 PWM outputs from my reprap shield which are boosted using 54A MOSFETS. These should happily drive my extruder heater, heated bed, fans, extra motors, whatever.

I've posted the files to thingiverse. I've also added my single-sided stepper driver files to a thing as well.

I now have four working stepper drivers, one mega shield, and a completed heater PWM board. Only a couple of thermistor sensors, and I'll have a complete set of electronics for a mendel :-)

Saturday, 19 June 2010

RepRap host software on Mac

Just a quick note to anyone trying to get the RepRap host software to run on a new Mac (Mac OSX 10.6.3).
I downloaded the software from the wiki and unzipped it.

To get it to work, I had some problems trying to make it accept a classpath. Eventually I did the following:

Make a directory ~/Library/Java/Extensions
Copy any files with *.jar and *.jnilib extensions to that directory.

The librxtxSerial.jnilib file supplied in the reprap software didn't seem to work. I found one at
http://iharder.sourceforge.net/current/java/ and I replaced it with this newer one.

Go to the reprap host software directory in a terminal window (you need to be in a directory with the rr-logo-green-url.png file in it).

type 'java org.reprap.Main'

This brings up the main reprap windows on my mac, and I was able to load and slice a .stl file. YMMV :-)

UPDATE:
As pointed out by Tony, this is not the most elegant solution. It doesn't help that I was looking at the 'mac-experimental' version from last year, rather that re-building from source :-( oops.

I also found out why I was having problems with the classpath :
java org.reprap.Main -cp $CLASSPATH 
is NOT equivalent to
java -cp $CLASSPATH  org.reprap.Main 

Doh!
This is usually true of any other command-line program, but any arguments AFTER the classname are passed to the class Main() method. I blame late-night programming :-)
Ignore all the java/extension rubbish, just use instructions from
http://tonybuser.com/reprap-host-on-osx-snow-leopard

A command line that also works is
 java -cp "*" org.reprap.Main 

Wednesday, 9 June 2010

Monday, 7 June 2010

Apple service and board PDFs

A few weeks ago, I bought myself an Apple MacBook Pro :-) and I've been really happy with it. However, a few days ago, I had terrible trouble trying to load the Ardunio software - segment faults and Kernel Panics (serious errors!) all over the place.
After a bit of debugging, I tracked it down to a single command - 'java -d32' which would cause a segmentation fault or bus error straightaway. A bit more investigation led me to the Apple Hardware test - which reported a 4MEM error, indicating a bad stick of ram :-(.

I dropped into the apple store today, expecting a delay as they had to send my nice new MacBook off, or at least swop out the ram. The apple 'Genius' was very helpful, and confirmed the bad ram - or possibly a logic board - and went off to speak to the manager.
However, 10/10 for service - despite the fact that I'd been using it for 6 weeks, they arranged a swop for a brand new machine right away! They even copied everything over to the new machine! I picked up my 'new' pc, opened the lid and everything was exactly as it had been on the old machine. I am now a very happy Mac customer :-) - that is an excellent example of customer service.

Also produced some PDF files for the Mega shield - available with the eagle files on the
Eagle files for Renoir's RepRap Mega Shield Page.

Friday, 4 June 2010

Renoir's Mega Shield built

I've been soldering and building and I've finished my mega shield!
From RenoirsMegaShield
The build went well. I 'tinned' the copper pads (using some plumbing flux and a tiny bit of solder), which made the soldering a bit easier. Using a tip (from ladyada?) I converted some standard header pins to some through-pins by pushing them through using the flat on a pair of pliers, three or 4 at a time:
From RenoirsMegaShield
Once I'd fixed the pins, I could put them through into the arduino and check the alignment - OK. I left the pins partially pushed in to maintain the position, and soldered a single pin from each row:
From RenoirsMegaShield
This held them in place when I removed the mega and soldered the rest.
From RenoirsMegaShield
I've now got 10-pin IDC headers for X,Y,Z, and extruder (A) - and a spare (B) using header pins as I ran out of sockets. There's a space for the 20-pin interface connector from the generation 4 designs, and a whole set of +5v/GND/analog in headers for temperature probes, extra sensors, etc. Along the top is an I2C 4-pin header, and similar +5v/GND/digital I/O headers for servos, TX/RX comms, and some PWM pins. 8 PWM outputs are taken to a separate 10-pin IDC header that is intended to go to a MOSFET power driver board to drive the heater and heated bed (coming soon).