# calculating board costs

#### MrDEB

##### Well-Known Member
need to order some boards and am wondering if I calculated the square centimeter conversion from square millimeters.
board is 100mm x 100mm which comes out at 9,655 square cm surface area
the board house has 10- 10cm x 10cm boards for $9.50 but I need 50 boards but for 50 boards with 25cm surface area is$34.50 then add on $$for 100sq cm surface area.Looking at 80 for 50 boards. thinking either I miss calculated or a misprint with the board house?? have sent board house an email inquiry and hopefully a mis print?? #### DerStrom8 ##### Super Moderator Most Helpful Member I'm not sure I'm following your question very well, but I wanted to point out that panel size is a HUGE factor when determining individual board costs. It all comes down to how well your boards can fill up each panel. #### JonSea ##### Well-Known Member What size are your boards? How many do you need? Are you sure you want to order a large quantity of an unproven board? If your board is 100mm x 100mm, it is 10cm x 10cm. The area of a 10cm x 10cm board is 100cm. It's easiest to calculate area if you convert the length to the desired unit first. If not, you need to account for the square of the conversion factor. 100mm x 100mm = 10,000 mm^2 x 1cm/10mm x 1cm/10mm = 100 cm^2 #### MrDEB ##### Well-Known Member the boards only have printing on them. Had some 10x10cm boards that I missed two traces/. We used them as drink coasters. We have a craft fair in May so I want to get 50-10 x 10cm boards. Diptrace says it is 9655 mm surface area which is 96 sq. cm. which doesn't sound right?? But if it is well I will order 5 units of 10 boards each. This way I can get different colored boards. Have you ever inserted a picture or image on a pcboard?? If the Seahawks logo wasn't copyrighted I could sell lots of the coasters but that copyright. #### JonSea ##### Well-Known Member Area = length × width If the board is 10cm × 10cm, what's the area? Yeah, pity those pesky copyright laws get in the way of profiting off of others work. #### MrDEB ##### Well-Known Member Diptrace says it is 9655mm square surface area got an email back from the board house and David is going to converse with the factory about pricing. #### JonSea ##### Well-Known Member If the board is 100mm x 100mm as you claim, the area is 100cm^2 or 10,000mm^2. If Dipstrace says otherwise, either your sides aren't 10cm in length or Dipstrace is broken. This is simple math. Your opinion does not count and there can be exactly one answer, which I have stated. #### MrDEB ##### Well-Known Member I checked Diptrace for accuracy and then it dawned on me the coasters I designed has 20mm radius corners. So yes I have a board with 9655 sq. cm. Then corners got me. So how is the knee replacement? Looking at having similar but only one of three knee compartments done. This way the ACL is not cut and it's a out patient procedure. I need to lose some weight, my BMI is too high. #### JonSea ##### Well-Known Member You pay for the smallest rectangle that will contain your board - nobody wants your corner trimmings. If your board is a circular disk with diameter of 10cm, its area pi × r^2 = 78.5cm^2. You are charged by the area of a rectangle that will contain the shape, a square 10cm × 10cm = 100cm^2. Really? What is so difficult to understand here? #### MrDEB ##### Well-Known Member nothing, I realize the board is 100cm square thus 90 for 50 boards or 50 for 50 boards at 10 per 10 boards. I emailed the board house and inquired about price issue and David is going to get back to me about pricing. A 25 sq. cm board for 50 is 34 BUT add 60 for 100sq. cm board. #### JonSea ##### Well-Known Member You could class up your coasters if you did them in ENIG (gold) plating with exposed copper. I did that on some speaker hold-down pieces recently. Virtually no one will see them but me, but I'll know they are there. For a monitor I made recently, I used circuit boards for the cover panels. It was the cheapest way to get cut-to-shape panels with silk- screened labels. #### large_ghostman ##### Well-Known Member Most Helpful Member Have you compared with dirty pcb? the boards are exceptional value. #### mypcbshop.com ##### New Member need to order some boards and am wondering if I calculated the square centimeter conversion from square millimeters. board is 100mm x 100mm which comes out at 9,655 square cm surface area the board house has 10- 10cm x 10cm boards for 9.50 but I need 50 boards but for 50 boards with 25cm surface area is 34.50 then add on$$ for 100sq cm surface area. Looking at \$80 for 50 boards.
thinking either I miss calculated or a misprint with the board house??
have sent board house an email inquiry and hopefully a mis print??
I'm not sure I'm following your question.
Anyways, whether you're going to do it by yourself or by using a manufacturer like us, there a few factors you want to keep in mind.
1- first off, size: you have already talked about it, so let's move to the second parameter
2- number of layers: 1 layer? 2 layers? 4? 6? Cost would obviously increase
3- silkscreen: on top only? Bottom only? Both side?
4- last but not least, the finish: "standard" would be the so-called "hal lead free", but many people prefer the so-called "ENIG", which is about golden parts and it would cost more.

Basically what I'm trying to say is that there are so many factors to keep in mind - I listed 4 only, the basic ones, but there are plenty - therefore it is really hard to answer to a question like this one.

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#### roy_witkey

##### New Member
I think it is a 1-side or 2-sided pcbs.