Hammond G4B - tuneup

[MikeHenry]

I recently took delivery of a Hammond G4B Glider and am in the process of tuneing it up. A rather rambling description of my progress thusfar can be seen here:

http://member.newsguy.com/~mphenry/hamm ... -o-saw.htm

I have a few questions:

1) What is the best way to pull the arbor bearings and install new ones? I have a small import, ratchet-type arbor press and new bearings on order.

2) The SHCS that attach the arbor housing to the pivot arm seem to be solidly locked in. Is there some trick to getting them out?

3) There are a couple of threaded rods (studs?) protruding from the arbor housing just adjacent to the SHCS with a hex nut on each. What is the purpose of these rods and nuts?

4) Anybody got a manual for the G4B? I've already got what OWWM has on their web site.

5) It apperas that Hammond recommended *not* lubricating the ball bearings. Was that to prevent swarf from getting gummed up?

6) If the bearings need to be replaced, is there a specific spec that needs to be met or can nominal sized bearings be used? What alloy of bearings were used?

7) This saw came with a 1 HP, 3-phase motor. I may install a VFD to power it, but a friend has a 1.25 HP, 2500 rpm DC drive and controller that he might sell me cheaply. Would this be a good match for the saw?

Where do you guys get your blades - Forrest? I'd be looking to cut mostly plastic, but some wood and possibly aluminum or steel.

Thanks, Mike

[crzypete]

Hi Mike, Welcome aboard.

I spent the last ten minutes reading your detailed Hammond journey on your web page. You have gone places in the Hammond saw that I have not- and I have owned 15- I've never had the table off, neat to look at the bottom.

As said before the G4b that you own is a superior saw, You will be very happy with it.

anyway, let's see if I can tackle some of your questions

1. from where you last left off on your site, the next step would be to loosen the little set screw on the absolute outside of the arbor casting- these hold that ring in place. after this is done you may find that you do not even need the spanner wrench, it may simply come off with a straight same diiameter drive pin inserted in the spanner hole and spun by hand- I have found these are not tightened to very high limits- hence the two set screws to hold them in place.

You may want to not the position of the front one which is identical in set-up- when it all goes back together this will control the exact position of the saw blade to the tables.

It's been my experience that you will not need to get as nasty as an arbor press, the bearings are lightly held in place and will be happy to come out with light persuasion and the right size blocks. In fact where you are now you should be able to tap the arbor right out from the rear. make sure it is all the way up to clear the table.

another thing of note, the nut on the lefthnad side is actually a drawbar- much like a bridgeport that attaches the faceplate on the righthand side- you can remove it any point. rember that the faceplate is the most important part of this hole set-up- it's condition will determine how accurately the saw works down the line.

2. don't know any tricks to removing them- never have attempted.

3. Actually they are threaded blind taper pins- the nut are there to remove them. They are very important to align the arbor assembly to the rest of the saw.

4. still looking...... any one else?

5. Most of hammonds advice on saw maintenance was cleaning. For the table bearings I have had excellent results in simply keeping the ways clean. I would not though if there is rust in there, you will need to use some lubricants to help unstick it...... I'm sure others have some experience here.

6. I am assuming we are talking about the table bearings? If so I have never gone there... for the arbor bearings- it's a saw. I used standard grade bearings and have been happy, nothing fancy.

7. I Believe all of mine have been 1 hp ac motors. I think they offered a DC drive at some point, but don't have much knowledge on the subject. I would guess it would work. Do you want the variable speed capacity? I would think for cutting plastic you would be fine with a cheap static converter- it would certainly make the switching of the saw more elegant.

8. I get my blades from Forrest- they use a super hard grade of carbide- c4- excellent for wood and probably great for plastic. Unacceptable for aluminum and certainly no good for steel. For aluminum you want a c2 blade.

I don't think I would cut steel on the glider- not designed to do it and I would not think it would be good towards the precision of the saw.

The forest blade I use is a 7.25" woodworker 1 that's a 60 tooth blade. You will need the three countersunk holes drilled into it- I believe they charge 7.50 a hole- you do not need the three larger holes in the face plate. the arbor hole those blades come with is a diamond hole- it should fit without them boring it, perhaps some slight filing at home.

Lastly on the G4b in order to fit the 7.25 blade you may need to do some slight filing on the throat of the saw- it is so slight that you will not see it from the outside- just a tad of clearance downwards from the top at the front of the throat plate. It's definitely worth doing in exchange for the slightly larger blade that you can put on. It only comes in affect at one small point in the travel.

Hope this answers the questions.

any more? ask away......

Pete

[Guest]

Hi Pete,

Thanks for the thorough response - it's been a big help. I'm a bit embarrassed to admit it but didn't realize that there was a draw bar in the arbor, though it sure made sense once I read your post.

It turns out that the spanner wrench was needed, but just to get the retainers started. After that they came out pretty easily by hand. The arbor was more difficult to get out and took some fairly aggressive hits with a dead blow hammer. Ditto on the bearings. I ended up using a 2" Delrin rod and dead blow hammer to remove the bearings. There must be a better way!

This assembly has a bearing spacer (tube) inside the housing between the bearings - is that typical of what you've seen? One of the docs on OWWM site shows sectioned views of 2 different arbors for different serial number ranges of a Hammond Mercury saw and this arbor seems identical to one of them.

Thanks for the tip on the blind taper pins - I gather that they orient the blade perpendicular to table travel.

On item 6 - yes, I was referring to the table bearings and was wondering if Hammond used stainless or carbon steel ball bearings and if there was a particular diameter spec for them. Probably doesn't matter, especially if the existing bearings are in good shape.

OWWM has a Parts & Supply Bulletin for the G-100 and G-140 TrimOSaws and it looks like the maintenance info there can be followed for the G4B.

The DC motor is just the simplest way for me to get the saw powered up at present. It came with a 3-phase motor but there's no 220 VAC service in the garage, where the saw resides and the DC motor/controller can probably be had for less than what a VFD or static converter would cost me and I wouldn't have to run 220 volt service out there. Variable speed might be nice for sawing different materials, but is probably not necessary.

I'll probably order a Forrest blade, though the carbide-tipped blade that came with the saw should be good enough to get me started.

Cutting steel with a table saw makes me nervous but Tenryu sells a blade for circular saws that seems to do a good job in that service and they've gotten good reviews in newsgroups from those that have tried them out. The videos on the Tenryu web site are impressive, so it's probably worth a call to see what they say about the idea.

Sounds like filing a notch in the throat will be a necessary evil to use the Forrest blade, though I kind of hate to "butcher" an old tool like this.

I spent the last ten minutes reading your detailed Hammond journey on your web page. You have gone places in the Hammond saw that I have not- and I have owned 15- I've never had the table off, neat to look at the bottom.

Friends accuse me of being a tad anal retentive on certain subjects. Since this saw will sit in a garage, it's probably a good investment to deal with the rust now while it's not too bad than to wait for a few summers and winters here in the midwest to take their toll.

Thanks for all of the input. I'll probably be back with more questions soon.

Mike

[crzypete]

HI mike, the filing as you will see is hardly a butchering. I am the last person who would want to butcher a machine- especially a glider- this is an improvement that, if done properly, will never be seen. I filed it at an angle- so you can only see it with the table pulled all the way back. you will understand one you get the blade- it is a minimal amount of material to be removed.

The bearing assembly sounds like what I have seen, I think they are pretty similar through the different saw models.

I have found that aside from cleaning the ways, the most important maintenance step is the aligning of the balls.- pushing the table to the extremes of it's travel and bumping it a couple of times- this keeps the table sliding to it's extreme limits and keeps the balls aligned from side to side.

I would think that you would not need to replace the table bearings as there is provision to take up wear and they should wear evenly.

pete

[Mike Henry]

Hi Pete,

"Butcher" was a more harsh than warranted - sorry about that. I meant that decisions to make permanent changes to a tool are not taken lightly.

Is there any reason not to pull off the sliding table to inspect the table ball bearings? Or special procedure for same?

I can see some "grunge" in the ways, but it looks like that will clean up pretty easily. I should find out later today.

I've got a 5-day weekend and expect to spend some serious time with the saw. Hopefully a friend will be back from a trip so I can do some bead blasting on small parts at his shop, but there is still a lot of rust removal that will require hand work. That can be satisfying if not tedious.

Mike

[Mike Henry]

I spent the better part of the afternoon and evening rubbing away at the surface rust on the table top, with several breaks to give my wrists a rest. The table top is cleaning up fairly well with WD-40 and a fine/medium abrasive pad. I may try to electrolytically clean some of the small parts, especially the threaded end of the arbor. Never tried that before, so practice on some rusty stock seems advisable.

The grunge in the ball ways cleaned up well with brake cleaner and a paper towel and the table slides more nicely now. I'm still thinking about pulling the sliding table to check the balls and clean out the grunge at the center of the ways

The web site above has been updated with progress to date.

I'd be interested to hear what others think of the table condition, especially the rubbing patterns.

Mike

[crzypete]

Hey Mike, no offense taken with the "butcher" reference, I am the last person who would like to butcher a tool. Aesthetics are very important to me, it would be very hard for me to make an improvement that doesn't look good, this fortunately does not fall into that category. Honestly when done right, no one wil notice that it was done.

As to rust removal techniques, I am not a big fan of sand/ bead blasting any surface which will not be repainted.

Removing rust:

For the top of the saw I would use a random orbit sander followed by a belt sander with a scotchbrite belt- all of this done dry. Try to work the three distinctive areas of the top separately. This should clean tat little bit of rust within 20 minutes and have te top looking like new. If you don't have these sander go for a block and 150 grit sandpaper, then step up to 220- see how it looks if you want to go finer proceed from there. afterwards coat with paste wax and buff.

For any threaded parts I like a bench mounted wire wheel. One with crimped wires- not knotted ones (too coarse). makes quick work of rust and paint and leaves a nice patina.

I would not be afraid to pull the table, it's easy enough to do. Just understand that the balls are going to come out. Start by removing the stop then just pull the table and catch the balls. to reinsert it is pretty much the reverse, followed up by a good table alignment of knocking the table to it's extremes- as described earlier. This will give you a good opportunity to clean the balls.

Thanks for the link on the site, and kepep the questions coming.

Pete