DW 788 blade forward travel

[redbeard]

Greetings to the forum! A bit of preamble, and a question about DW788 cutting:

J


Is that normal?
How far does the blade normally travel forwards and back on this saw?
Is there any adjustment for that?

I measured it with the blade really tight, stopping at the top of the stroke and putting some wood at the back just touching the blade, then turning on and off to get the blade at the bottom of the stroke, and measuring the gap behind the blade.

Or maybe it's just my complete lack of skill...
Thanks,
Alan

[Mick Walker]

Alan, I looked long and hard at the Dewalt 788 and the Delta P-20. The aggressive motion of the 788 was one of the reasons I purchased the P-20. I can adjust the back and forth motion on the P-20. I don't believe you can on the 788. There are many that love their 788's and I think it is something that you have to get used to. Maybe a blade with more teeth per inch would help you. Delta no longer makes the P-20 or any scroll saws.

[ubgoofy2003]

Hi, Alan. By the way, that's my son's name. Good to have you on the forum. I have checked my 788 & it does that also. But, since the forward motion is the direction you will be cutting, that shouldn't be a problem. I do understand about the turning though. It does affect the tightness of a turn. Maybe someone else has a solution, or is aware of this and what to do for it. I don't know about taking the saw back since it was rebuilt. I really do like my saw though, not perfect, but, love it anyway. Good Luck Perk

[redbeard]

Thanks for the replies - most appreciated. Since it's a "refurbished" saw I was concerned that it might be out of alignment, and they only have a 30 day return policy (but 6 months warranty). So you've set my mind at rest.
Now it's just practice...

[Ocelot]

Hi Alan,

I had the same problem and was really frustrated. It was so bad that I could not cut anything intricate at all. I couldn't find an answer and didn't know anyone with a Dewalt to compare it to.

People thought I was exaggerating so I ended up videoing the front to back motion and sending it to Steve Good who has a Dewalt. He was shocked and sent me a video of his which was fine. He couldn't believe I could cut anything like that.

Anyway, after getting no answers from Dewalt or anyone else on a fix, I took matters into my own hands and corrected it myself. The saw is wonderful now.

Here is the problem - The length of the top arm is longer than the length of the bottom arm. Or at least the mounting holes are off. (of course it could be opposite on yours) What I did to test this was remove the 4 torx screws that hold the bottom silver blade holder pivot assembly to the yellow frame. I moved the entire assembly out away from the yellow frame nearly 1/8" and temporarily clamped it in place. I ran the saw slow and the blade travel was nearly PERFECT! WooHoo!.

To make the fix permanent I had to use a dremel with a cutting wheel to make the 4 holes in the yellow frame into slots. Basically, I cut the metal so the holes were slots to the end of the piece. This allowed forward adjustment of the silver blade assembly.

The saw is wonderful now.

The type two saws made in Asia don't have the quality control that they did when made in Canada.

Just to show everyone how bad it was, Here is the video that I sent to Steve Good showing the problem. Steve was great taking the time to send me a video of his saw when I emailed him for help. I don't have one showing the "after, but there is only normal slight elliptical blade travel. A piece of wood behind the blade barely moves now.



Ray

[ubgoofy2003]

Thanks for your input Ray, I should have looked into it myself. I didn't like the travel either. It has been a problem turning corners, etc. You have inspired me to look into things when I notice them, from now on. Thanks again. Perk

[Ocelot]

You're welcome Honestly, I think mine was particularly bad. Based on what I've heard from other users and a video Steve Good sent me of his saw in action with a board behind it like in my video, his was fine.

I think there are variations in the way some parts were made. I LOVE my Dewalt now that it is fixed. "Old Yeller" has been great for me and a huge improvement over my old two speed dremel and 16" sears saw.

Ray

[VB...]

Thank you Ray!!! I've seen some forward travel on my DW as well. Not as bad as your on the video. I too thought "hay it has to be this way". Obviously not.

Thanks again,
VB...

[knothead]

I had a Delta with the same travel. Hated it. Especially on tight turns and intricate cuts. Sucked it up and got a Hegner. Front to rear travel is .06 inch. Incredible difference. You can put your finger up to the blade and it won't cut you.

Tom

[jerman46]

Thanks for the tip as i have the same problem and i will check out my dewalt. I was ready to go back to my Craftsmen saw .

[RFortier]

Ray-

From one Ray to another! I'm sure glad I saw this thread now because I've had my mellow yellow since April and I'm just about to hang the FOR SALE sign on it.. Had it to a repair shop and they said it worked just like it should. Looking at your video I'd say mine is as bad as yours was! Thank goodness I kept my Craftsman.

I took out the 4 screws you mentioned but I can't move the assembly forward. It pivots on the bottom side of the assembly but not more than a fraction. Is there another screw to loosen? I don't want the whole thing falling out.
Thanks for any help you can give me.

Ray F

[Ocelot]

Ray-

I took out the 4 screws you mentioned but I can't move the assembly forward. It pivots on the bottom side of the assembly but not more than a fraction. Is there another screw to loosen? I don't want the whole thing falling out.
Thanks for any help you can give me.

Ray F

Hmmm, It's been a while and I was trying several things from scratch, but I can think of two things. If I recall correctly, It needs to be done without a blade and you may need to give the motor a half turn or so with a flat head screw driver. There is an opening on the back of the motor and the motor shaft is slotted.

I don't think the assembly moved easily though. I know to tighten down the screws after slotting the holes, I used a flat screw driver between the yellow frame and the assembly to hold it out. It may not be necessary, but I think I also had to adjust the tension rod under the switch housing a turn or so to give it enough play to move the lower assembly. I was trying to figure it out as I went along from scratch, and trial and error, so it's hard to give a step by step instruction

IMPORTANT - The assembly must be straight for the final clamp down - Meaning that the gap you create between the yellow frame and the silver assembly must be equal on both sides to keep the blade straight.

Also, I wouldn't make any permanent modifications or slot the holes until you test it first. If you can get the blade assembly moved out even a 16'th of an inch, and put something in there to hold it temporarily, you can put a blade in with just enough tension to take up the slack and test it. You can test it by putting a metal ruler or something behind the blade and turning the motor by hand to see the difference.

There is an instruction on line for adjusting the tension rod here. Tune

Ray

[knothead]

I had a Delta with the same travel. Hated it. Especially on tight turns and intricate cuts. Sucked it up and got a Hegner. Front to rear travel is .06 inch. Incredible difference. You can put your finger up to the blade and it won't cut you.

Tom

My bad. Too early. The blade deflection on a Hegner is .006.

Tom

[Ocelot]

I had a request from Rick for a picture of what I moved to achieve near zero forward blade travel.
It's a bit blurry since my good camera is hiding from me and I had to use an old cheapy. It should give an idea on how much I moved it. You can see the new gap between the lower blade assembly and the yellow frame. just over 1/16"

Ray

[ubgoofy2003]

Hi, Ray, you sure stirred up a bee's nest here with all of our 788's. I took mine apart & checked it out, but, the rocker arm holds the assembly from moving out equally at the bottom & top. I did get it adjusted, but, has a little angle from top to bottom. Works fine though. Thanks for bringing it to our attention & helping to correct the problem. Good Luck Perk