Expen$ive material$... how do you deal with it on low charged jobs?

[paco]

I was wondering how other "Botters" were dealing with expen$ive material$ in low charged jobs? Figure a 100$ charge for CAD/CAM and machining in a provide by customer 600$ sheet of material... do you charge for the risk of having to replace the material or are you firm beliver?!
Please...
need opinions...

[olecrafty]

Paco

I buy some cheap foamboard from home depot and try the cuts first. That will lessen the chance of error. Hopefully you will catch the problems before you cut the real thing.

As for the charges I have charged both ways. If the customer is a good repeat customer I will take the chance of a mess up. If it is a one time only deal then I will factor in some cushion. Not the whole amount of course.

Kaiwa
olecrafty@charter.net (mailto:olecrafty@charter.net)

[stevem]

The best way to deal with it is...don't screw up.

[john_r]

Paco,
How about a cheap piece of 1/4 plywood or MDF? $10.00 - $12.00 a sheet in my neck of the woods.

[KSimmerer (Unregistered Guest)]

I have two rules:
1: If I buy the material, I mark it up, usually by 1.3 to 1.5 markup. This covers me for risk etc.

2: If you supply the material, you take the risk. I explain that if they supply the material, they are making the money, I don't have the margin to replace the material, they do. I give them a firm figure to cut the job, an estimate on how much material it will take. I also explain that problems such as bit breakage or failure, power outages and surges, hold down failure, human error or sometimes just the nature of the project can cause loss of material that will require recutting of some parts. I explain that I am a professional and do everything possible to pre-flight check before cutting including previewing in 2d and 3d modes and air cutting, but that it is not unusual especially with small and light items to have loss requiring recut which I will do at no additional charge, but you must provide whatever amount of material it takes to finish. If it can't be recut from a drop, then You must buy another sheet. I tell them this in writing before cutting. I have never had a problem when explained and agreed to in this manner.

I make money or I don't do it, I don't need another hobby.

PS preflight cutting with cheap material is a great idea if it is your material, and I would factor that into job costing. If it is the customer's material it is also a great idea to me, so long as they are paying me for my time! I am a firm believer in getting paid for what you do and what you are worth. Your customer doesn't expect you to give your work away. If you do, he just figures you must not be worth much! The fact is you are just as good as the next guy, probably better, don't give your work away, but do offer quality and service.

Keith

[paco]

Thanks for your post KSimmerer!
I too would charge if I would be supplying the material (most of the time since my startup, customers have choose to supply their material)... more, I would ask for a 50-75% deposit for material fee BEFORE begining the CAD/CAM and/or the machining.
When I do VERY high risk parts machining like p'etty small parts, I warn the customer about the fact that I might have to recut some and this will need some more material AND that I will be assuming the recuting AT no charge since I can normally know in advance and plan this... unless the jobs is about 99.99% risky; that I call for a tesing first. Normally at no charge since I will be learning from this... unless special material needed that is most of the time supply by the customer readily.
All of this is normally accept by the customer that I have work with for now. The part I am less confident about is when the material is high priced like a 2" thick HDU sheet (4' X 8') that the customer want a 3.5' X 6' sign in it and that the design he need is quite simple... In a such case, the BASIC charge for such CAD/CAM and maching can be quite low compare to the material value; if something go wrong, I could be loosing the nest 5 to 10 profit!!! About the thing that could go wrong that I am mostly concerned about is power faillure and control software crash. This last one as happen quite often lately and I just can't know when and how it will be the next time!?!?!? I'm quite confident about my preparation and programming which I included in my bid but not about my tool software reliability lately which is, I believe, a true reality! As power faillure too...
I would be quite uncomfortable charging a customer my CAD/CAM/machining part AND a replacement sheet in the above discussed case... and even if I plan a 25-50% mark-up on the job, this is just to cover my stress!!! For now I have followed Steve's recommandtion as to "DON'T SCREW UP!"... and keep on touching wood... since, I have been lucky!?!?!?

Anyway, thanks again for sharing me your views and opinions about this topics! I will be considering your points with consideration.

[jay]

Paco, one way to relieve the stress you feel about the software or machine crash, due to a power failure, is to purchase a UPS (Uninterupted Power Supply), they are pretty cheap compared to the cost of some material. They can also add a great deal to the piece of mind.

[paco]

Hummm... I may look for price about thoses... thanks Jay! Though I fear power faillure, ALL my crash since the beginning have'nt been due to power faillure; maybe from my computer... or from the control software itself... but Ted is actually looking closely to my crash report that I send every time I observe one... I'm now testing a not yet release and it look quite reliable but let look at it for some days since some of my issues are intermittent (I have difficulty to duplicate)... If I can get rid of most of thoses crashes, I will be MUCH more relax when machining expen$ive material$ and doing a first job for a new customer...
Thanks again!

[Chris@MustangAero.com]

How have people used a UPS (Uninterupted Power Supply)? If the power goes out but the computer and Shop Bot Box are powered by the UPS it will try to drive an unpowered router through the material. Seems like this will create a crash as bad as no power at all.

[mikejohn]

Chris
Would a standard 700va UPS power four stepper motors?
A UPS is great for surges, but not for power failures.
..........Mike

[ron brown]

If one cares to guard against a failure like this they can do several things. One is to put a relay in the power curcuit that will do an emergency stop when the power is lost. This will stop the router movment and retain the last line. A UPS powering the computer and the control board, but not the steppers, would allow one to properly shut down the computer. Noting the line number would allow one to return to that point.

Similar relays can be used to stop the machine if vacuum or dust control is lost. It all depends on how much time and thought one cares to put in a setup.

Ron

[elcruisr]

We run a commercial grade UPS on the computer and monitor and a voltage surge diverter (diverts excess current to ground) on the driver box. In the capitol of lightning strikes we've had a few power failures and surges while operating. It's no big deal this way, we just mark where we're at and shut down until things return to normal.

Eric

[donchandler]

I have a relay that is powered by the line voltage and it is hooked to the input that is the same as hitting the space bar. When the power drops out, the program stops immediately. The computer and stepper power supply are powered by a UPS. If the power is off for a extended time, I turn the stepper power and the moniter off. The computer can stay on quite awhile. This has saved my backside several times.

[beacon14]

Does anyone know whether the Alpha works the same way as Don's relay, since it controls the power to the router? Or do I have to go and check it myself?

[ron brown]

David,

The wiring would need to be done a little different but, it can be setup that way.

Ron