I give up! CPF exam question.


CGF II, Certified Grumble Framer Level 2
Apr 24, 2002
Pittsfield, MA - The Berkshires
I'm studying for the CPF exam and can't come up with their answer to this question. Either their answer is wrong or I'm dumb.

21. A good customer comes into your shop late in the afternoon. She needs her son's diploma framed for tomorrow. Her heart is set on a particular 3/4" moulding and you only have two pieces left in stock. To make her an 8 1/2 x 12 frame the pieces would have to be:

A. 20 1/2 and 30
B. 19 3/4 and 28
C. 21 and 26
D. 23 and 25 3/4

They say the answer is A. Are they right or am I dumb?
It seems to me they all would work.

12+ .125 + .75 = 12.875

12.875 x 2 = 25.75 That works for all the longer pieces?

8.5 + .125 + .75 = 9.375
9.375 x 2 = 18.75 That works for all the smaller pieces?

What am I missing? I guess thats why im not certified! Good luck.
The two shorts can be cut from the 20 1/2" piece, and the two longs can be cut from the 30" stick.
A. works, as does C. and D.
8 1/2 + 8 1/2 + 3 = 19"

Betty (I'm not a CPF and I don't even have a saw or a chopper!
"The two shorts can be cut from the 20 1/2" piece, and the two longs can be cut from the 30" stick."

Isn't that the case with all four choices? Im afraid I'm missing something and I'm really showing my ignorance here! Be kind.

Don't let the poor wording "pieces would have to be" throw you off. It is not an unusual error in multiple choice question writing. It should ask which combination would work? Then A becomes obvious because B, C, and D don't work.

Edit: Hey folks,

8.5 + 8.5 + 3 = 20 plus allowance for kerfs

12 + 12 + 3 = 27 plus allowance for kerfs

or 2 legs:

8.5 + 12 + 3 = 23.5 plus allowance for kerfs

Only A satisfies.

Pat :D
I know what stix would work but using the formula method from the book I guess I was looking for the answer to be what I get when I'm using their formula instead of the 'will it fit' method. I get:

8.5 + 8.5 + 3 = 20
12 + 12 + 3 = 27

Maybe they should reword the last sentance to be:

To make her an 8 1/2 x 12 frame the pieces would have to be AT LEAST?
8 1/2 + 1/8 + 3/4 + 3/4 times 2 = 20 1/4 ( for 2 8 1/2's)
12 + 1/8 + 3/4 + 3/4 times 2 = 27 1/4 ( for 2 12's )

That knocks B,C and D out.

This type of cutting is easier with a Morso, but very tight with a power mitre saw.

But what counts is what you actually have in stock
I did not take into consideration any allowance as ERIC has. I was really doing it to the book and for this purpose they did not include it. I feel very comfortable with the exam but this darn question was making me crazy.
How about two sticks of 24 3/4?

I like the way they fail to suggest the possibility of cutting different sizes from a single stick. That can take some creative math. Then try to miss the bad spots.
Eric is right that B may be possible. But it depends on the width of the rabbet and whether the ends of the leftover pieces are mitered or square. It's probably OK to assume a 1/8 inch allowance. Again I would urge question writers to cover all parameters or make sure that the answers cover any possible ambiguity.

I didn't add the 3/4 two times for each leg. I won't make that mistake again.

I would reword that question like this:

21. A good customer comes into your shop late in the afternoon. She needs her son's diploma framed for tomorrow. Her heart is set on a particular 3/4" moulding and you only have two pieces left in stock. How much would you charge her for putting every order on hold while you sift through tiny pieces of scrap moulding to make this one frame?

A $5 extra
B $10 extra
C $25 extra
D Look at the tiny pieces of moulding and say "I don't have that mouldning in stock" and go back to framing.
Eric is right that B may be possible.
Hey Pat - while you were typing your reply, I was using the edit feature and I took back my comment about "B might be possible". They say timing is everything!

Jay - I love it!
Lets not forget the confusion caused by calling the moulding 3/4". Is that the face or the foot? With a standard 1/4" setback on the rabbet from the face width, you could conceivably get the frame from sticks that are 1" shorter than the ones calculated using a 3/4" foot (1" moulding).
One of the downfalls of this business is a consistent use of descriptive words. I would hold the creators of the test at task if they were to be so vague in their premise.
Many of the problems that we find in the design, bussiness, and technical areas of framing require a multi step solution. This is one of those problems. 1 home much moulding do I need to build this frame? 2 If I only have two sticks of moulding in the back room which two would they have to be. As you all already know A is the only answer that will work.
I’m studing also…..

Answer A......

Remember for the CPF not only are you looking at the methodology of framing you are also looking at best business practices…..and in the case of this question the most economical lengths are A..

At least that my read on this question
…....and I looked it up... :D

This is from the CPF Study guide….my interpretation is that the questions have a best business practice element contained within them…..

Examination Content
Specifications for the examination reflect the knowledge
and skills essential to perform the job. The specifications
have two (2) dimensions. The first relates to the content
areas covered by the exam and the second relates to the
type of thought process to be used, including recall of
knowledge, application of knowledge and the solving of
examination consists of 150 multiple-choice questions.
Answer spaces are numbered to correspond with the
numbers of the test questions. You are to decide which of
the suggested answers is best and blacken with your
pencil. Be sure to completely fill the answer space.
Should you erase, do so completely; incomplete erasures
could be read as an intended response. Read the
directions on the test carefully to make sure you
understand them before attempting to answer questions.
The sample questions aren't revised as often or as carefully as is the exam itself. They're intended only to give a general idea of what the exam is like.

Over the years of revisions, PPFA's Certification Board has tried to eliminate wording that is vague or easily misunderstood to those who know the correct information. Candidates who have studied insufficiently, however, will be lost on a lot of the questions. Many years of shop experience won't substitute for learning what the Study Guide recommends. Details like frame allowance and normal waste must be considered, and terminology is important.

We just completed this year's CPF exam review & revisions and, as usual, we found some wording we wanted to improve. Perfection in wording questions, like perfection in anything else, is elusive.

Jim Miller, MCPF, GCF
Chairman, PPFA Certification Board
The elusive use of words…I’m going to have fun
…..I sometimes have problems interpreting what I say myself :rolleyes: …..never mind the difficulty between English English and US English….and then you should see the English Lance is using on the Australian Grumble :confused: ……Oh never mind……my mind wanders

Ahhhhhh…..I just noticed Jim’s title
….. “Chairman, PPFA Certification Board”…perhaps he may be open to a little bribery and corruption :D or he may cut us Grumblers a bit of slack ;) ……………really really really…….only kidding
Maybe they should give you all the question and all the answers first so you can translate it from "U.S. English" to "English English" BEFORE you take the test? Its only fare.
Another point a 3/4 inch moulding is normally 1/2 inch on the back side not counting the Rabat width. So your loss per piece would be 1 1/4 not 1 3/4. This is an important fact that I would consider in real life but would choose A., assuming it was a stupidly worded question. They really need to change the 19 3/4 to 19 1/4 to eliminate the confusion in all scenarios. The other valid point that was already made is how it was cut, chopper or saw, can have a impact on a scenario.

Well I wrote this two hours ago and couldn't finish do to mass number customers coming in.

I see after posting that this was already pointed out.

The answer is non of the above. When you have only two sticks left, the mill run will be off or the finish won't match.
((w+h)*2)+1/4)+(width of mldg core * 8)+(kerf * 4) is the exact formula.


B. 19.75+28=47.75

so, by straight mathmatics the answer is B
Originally posted by richm:
((w+h)*2)+1/4)+(width of mldg core * 8)+(kerf * 4) is the exact formula.

Ok. I've been in framing for almost a decade, and I've never seen the abbrivation "kerf". What exactly is it? I've never actually had to figure out the formula for figuring out feet, we always use a chart ;) . Thanks....
I'm having my Saturday night martini, so may be totally misguided, but I recall that "kerf" refers to the bit of the wood that is lost by sawing: The width of the groove made by the sawblade.

I beleive Rebecfa has the correct answer, but I'm having my Saturday night glass of wine.....
Well it IS saturday night and the bud lite is flowing like a river and I couldn't care less waht curf it. Have a good weekend friends.
I may be way out of line but I think the thing being confused here is the forumula as sighted by richm ( minus the kerf allowance) which will give you the total amount needed,as opposed to the fact that you "HAVE TWO STICKS LEFT" in your inventory.
Therfore if you assume that a bare minimum it will take an 10 in. length to produce a 8.5 in.leg and it will take a 13.5 in. lenght to produce a 12in. leg ;then you are left by deduction with the facts that in b.) you can not get 2- 8.5 legs from the 19.75 in. length but you can get 2- 13.5 in. lenghts from the 28 piece,but you can't get 1-10 and 1-13.5 from your first stick so that excludes that possibility.
In c.) you are faced with the same assumption since you can get 2 -10 in. pieces to get your 2-8.5 in .sides but you only have 26 ins. not the needed 27 ins. for the longer legs,also you can't mix the two once again ( 1-10 and 1-13.5 ) and come out to 26.so c.) won't work either. Then in d.) you can get the 2 -10 in legs out of the first stick but you won't be able to get the needed 27 ins. from the 25.75 in. length and you won't be able to get one of each from either the 23 nor the 25.75.
Therfore the only possible conculison to my understanding is A.) by which you can cut 2 -10 in lenghts into 8.5 on sidesfrom the 20.5 in stick and 2- 13.5 in. lenghts into 2-12 in. sides from the 30 in .stick.
Unless i am overlooking something it seems fairly obvious to me( even if you add the kerf allowances)
PS Besides Jim and the rest of the Cetifcation Board wouldn't be that devious nor that shortsighted. Or at least I think.LOL
Well now I have an even greater appreciation for ordering chopped and joined. At the current rate of confusion and aversion to memorizing formulas - let me scrape the mold off my college calculus books - it will be awhile before pursuing CPF.

Hickory Hollow Framery
What percentage of the CPF exam’s 150 questions must you gets correct to pass….I think this was covered some time in the past…I cannot find the thread….

Whilst I feel that it is important to understand what the exam is about…..I could very easily if I’m not careful get caught up in a question like the above and miss the BIG picture……I would expect that the exam is to judge our overall competencies, as it is unlikely that any participation’s would be an in-depth expert in every aspect and detail of framing (methodology, maths, etc.)…..my interpation of the exam is it is to test for overall competencies …….and it is not a maths exam or a specific exam but that it is an over all knowledge exam..

BTW if you are using the suggested study material the above question about measuring moulding is covered on page 28 of “Picture Framing” volume 1 (is there any other volume!!) and whilst it does not make specific reference to “kerf” it says……. “However you will need more inches to compensate for what will be cut away which makes the mitre”(in the real world what you would cut away would or could include “Kerf”) . …..also from the same book and chapter ”Measure across the moulding, including the rabbet” …….. from what I can see there is a bit of common sense built in to the questions to reflect the true workings of a framing business…..though if others have a spin on this I would be more than happy to hear it….

I was worried about this exam before I started to look carefully at the study guide…..but as I get into it I have found that it is less daunting than I first thought…..and as I said if I felt I would fail the exam by one question I would have to question my ability to take the exam……
By my math 8.5+ 2X3/4 (the width of the mouldingas waste)=8.5+1.5 +10 dependind upon the KERF (as I understand itthe width of the saw blad at the set of the teeth which may vary dependingon the make of the blade)could be as much as 10.25 or less but at max 2X10.25 =20.5 or without the kerf factor 20 not 19.75.
PS As I stated the understanding I had of the word KERF is the thickness of the blade acrocc the the teeth at their set ( where they lean left and right) .this is normally equally or very closely to the gap caused by the cutting of the blade which results in the saw dust on th floor or in the vaccum hooper.PSS Dermot your annalysis of the test degrre of difficulty is IMHO right on. It is much less daunting if you take your time ,reason to what they want to know,and utilize the knowledge you uase everyday in your shop.The premiss I saw was can you use this knowledge to arrive at the MOST economical and efficent use of equipment and materials in your shop..No tricks or devious questioning intened. You all should do FINE. If I did on my first try all of you certainly can. I am frequently in AWE of all the post I see here.
I taught at the post secondary level for 13 years and I can honestly state that I have never seen a single math question dissected to such depth as this one!!

I am just waiting for some enterprising individual to post, one at a time, all of the questions that were on the test so that I can dispense with the reading of sometimes dry text writings and get into each one of them to this depth.

(Gosh, where were all you math moguls when I needed you for the SAT's many years ago??)

Tom ;
I was eeeking by the SATs, so you know how well I think most here will do on the CPF exam if I managed to pass.By the way is everyone aware that there are study groups prior to the exams? and i think some ae even available in conference call formats .Check with the PPFA HQ or with your local chapter.I received an email from mine suggesting that they could arrange the study group if there was enough interest.
Tom ;
I was eeeking by the SATs, so you know how well I think most here will do on the CPF exam if I managed to pass.By the way is everyone aware that there are study groups prior to the exams? and i think some ae even available in conference call formats .Check with the PPFA HQ or with your local chapter.I received an email from mine suggesting that they could arrange the study group if there was enough interest.

The actual outside length of a 3/4" moulding with a 1/4" rabbet and a 1/8" allowance, cut for an 8 1/2" order is 9 5/8". Interesting isn't it how we all "agree" in these calculations.

Pat :D :D
Pat :
I don't mean to beat any dead horses and I do agree. But the question was what would you USE. so while:

The actual outside length of a 3/4" moulding with a 1/4" rabbet and a 1/8" allowance, cut for an 8 1/2" order is 9 5/8".

With the kerf on either end wouldn't you need a slight bit more lenght in the stick you cut those two 8.5 in with 1/8 allowance sides from,than 2X9 5/8 or 19.25 + 4 X what ever the width of the kerf is which could easily be 1/4 in. or a total of 1 in. + 19.25 for a total of 20.25 ( depending on the type of blade and the resulting kerf).But then I'd just order a bit more to be sure,unless I was the most precise moulding cutter around which i am along way from being .LOL But at any rate I still would suggest staying with selcetion A.)
I agree with Tom and Dermot, we are disecting this question entirely TOO much. If we did this for all questions ,it wouldn't matter how precise we were we wouldn't finish on time anyway and fail the test just the same.LOL
I think Tom might tell you that a good tip to takeing any exam is to do your best and give your answer promptly while not wasteing too much time on any ONE question so as to answer as many as you can thus increaseing your chances of getting more answers correct,other then being EXACTLY correct on just a few or maybe just ONE.LOL
More dead horse:

My point was that multiple choice questions should not have answers, like B in this case, that "might" be acceptable with different assumptions. As I said earlier I would have picked A absent a specific statement of parameters like Rabbet, kerf and allowance.

Pat :D
Guys calm down…

perhaps we should remember that the question is about the CPF exam and that there is a suggested study list to help with determining what you answers will be….this splitting of hairs over this question could be very disturbing to some of the people who are trying to study for the exam…..perhaps if your suggested answers were given in a way that reflect the information in the study material you guys would be more helpful……..

I for one love an argument or debate…..but in the case of the CPF exam for those that are studying it is not a debate it is about trying to sit this exam in the context of what the PPFA are setting….this thread has gone way off track……given the seriousness of this exam for some people…..perhaps there are people lined up to take the exam whose jobs may depend on passing….. some people could be on a probationary period and that securing a permanent position could depend on them attaining there CPF ….please guys lets keep questions about the CPF exam in context.

No pun intended….the CPF exam is not about scoring points it is about careers and livelihoods….

wtf, that's math!! :eek: Do they really test your math skills? What if you only took Framing Theory 101? If I wanted to be tested on math I would have finished college.

I put a simple math quiz on the end of my employment applications and people stopped handing them in. Lotsa recent college grads failed it too. Hard stuff like "What's 8 3/4" plus 4 3/8" and "Label this ruler!" So I took it off.
They only test you on the kind of math skills you might actually need in a frame shop, and they are not unreasonable.

Friday, I needed to cut eight identical frames from a 40' bundle of moulding. I had only a few minutes to decide if there was enough moulding or whether I should order more an delay completion of the order for another few days. I needed to give the customer a completion date and, if I needed it, I had to include the extra moulding on an order I was placing with L-J for delivery.

A quick visual inspection for flaws and a little 5th-grade arithmetic, and I decided I DID have enough, but it would be close.

I finished the frames with literally less than 6 inches of moulding left.

My children don't understand the value of math in the real world. They say they don't want to be accountants or engineers.

I guess they don't want to be picture framers, either.
My comments were tongue-in-cheek but I was a little surprised. I've often wondered what kinds of questions are on that test and what knowledge one needs to master to be a CPF. I figured it would be largely mechanical knowledge, conservation knowledge. Mathematically figuring your minimum footage to such a degree seems to be somewhat extraneous to me. Worthwhile and good for refining your overall skills, but not essential.

I don't know. Don't mind me. That's the only test question I've ever seen. It would have surprised me.
Johnny ;
It's been a Looooong time since I took the test(1988) but I vaguely remember another question about the number of mats a given size that could be cut from an unknown number of sheets of matting.But it was very similar to this question in that it required you to utilize some different placement to get the maximum mats from the least number of sheets. However this is something that could be very useful to a shop owner and should be (as Ron so aptly pointed out) common math for a framer.
However for anyone who is really interested in seeing what type of questions are asked ( not the actual test question) there use to be and probably atill is a sample questioner provided by the PPFA for the asking.While I think it was simplified it was somewhat fun to see if you could answer.
I think that I've known about the test for so long without ever seeing it that over time I've given it near deity status in my head.

Getting maximum yield is something I absolutely want my employees to know.
I said "By straight mathmatics" I did not say it was necessarily possible.

carfully cut on a twelve inch ulmnia (sp?) saw it is entirely possible.

The original question can have two possible correct answers. One if it is asumed the .75 mldg. dimension is the core dimension (for such a calculation the only real one that matters) or you asume it it the total mldg width.

This is the problem with the CPF exam. In many cases it is not no could it ever , in it's current state, be practical.

If you took all the questions in the exam and applied "practical knowlege" to the answers you would get the majority wrong. I have known several framers with many years of experience go down that road to their dimise.
Originally posted by richm:
I have known several framers with many years of experience go down that road to their dimise.

Had they followed and studied the CPF study guide!!!!.....If they had and failed…..I would have to question whether they should be Picture Framers.....

I would have felt that the CPF exam made very little sense when I had a quick look at the study guide a few months ago (Crap I said to myself)…. for a while I let my arrogance get the better of me…… then I had a better look at it and read it in full……and started to follow the suggestions that they make in the guide about the study material I should be reading…..then it started to make a lot more sense to me ……

…….and I have to say now that I’m following the guide I have being pleasantly surprised by how much I do know……..but I have also being very concerned by what “I don’t know” ……..the CPF study guide in my mind is to get me thinking not about what I know but what “I don’t know”….
I started out as a chemical engineering major in college. My sophomore year, I took organic chemistry. I had enjoyed chemistry up to this point and had always done well. I actually believed you could succeed at organic chemistry using common sense and deductive reasoning. I did not memorize the hundreds of chemical reactions.

I got an 'A' in the lab and flunked the class, which was based entirely on a 3-hour final exam. By the next semester, I was a geology major. (You can't reason your way through geology, either, but you take better field trips.)

For those of you contemplating taking the CPF exam, study the recommended materials, and specifically the pages they tell you to study. Do NOT rely on 25 years of experience, common sense or something you've read on The Grumble.

If you don't own the materials, borrow them. Many PPFA chapters have lending libraries for this purpose.

The CPF exam was probably the first and only test I've ever crammed for. I actually took the books to Chicago with me in 1987 when I took the test, locked myself in a very nice room at the Hiatt Regency, and re-read everything.

You might want to allow a little more time. ;)